AFM-CDC-Review-2011.Pdf

Vol. 21 • No. 5 • March 8 • 2011

www.afm-journal.de

AADFM21-5-COVER.inddDFM21-5-COVER.indd 1 22/11/11/11/11 6:50:316:50:31 PPMM www.afm-journal.de www.MaterialsViews.com Carbide-Derived Carbons – From Porous Networks to Nanotubes and Graphene

Volker Presser , Min Heon , and Yury Gogotsi *

FEATURE ARTICLE FEATURE from carbides has attracted special atten- Carbide-derived carbons (CDCs) are a large family of carbon materials derived tion lately.[ 3,4 ] Carbide-derived carbons from carbide precursors that are transformed into pure carbon via physical (CDCs) encompass a large group of car- (e.g., thermal decomposition) or chemical (e.g., halogenation) processes. bons ranging from extremely disordered to highly ordered structures (Figure 1 ). The Structurally, CDC ranges from amorphous carbon to graphite, carbon nano- carbon structure that results from removal tubes or graphene. For halogenated carbides, a high level of control over the of the metal or metalloid atom(s) from the resulting amorphous porous carbon structure is possible by changing the carbide depends on the synthesis method synthesis conditions and carbide precursor. The large number of resulting (halogenation, hydrothermal treatment, carbon structures and their tunability enables a wide range of applications, vacuum decomposition, etc.), applied temperature, pressure, and choice of carbide from tribological coatings for ceramics, or selective sorbents, to gas and precursor. electrical energy storage. In particular, the application of CDC in supercapac- The growing interest in this fi eld is itors has recently attracted much attention. This review paper summarizes refl ected by a rapidly increasing number key aspects of CDC synthesis, properties, and applications. It is shown that of publications and patents. A signifi cant the CDC structure and properties are sensitive to changes of the synthesis progress in CDC research has been seen in parameters. Understanding of processing–structure–properties relationships several fi elds. Various carbide precursors have been systematically studied. Studies facilitates tuning of the carbon material to the requirements of a certain on binary carbides with different grain application. sizes show the possibility of low-temperature carbon formation for nanopowders. Also, a better understanding of graphene 1. Introduction formation during high-temperature vacuum decomposition of silicon carbide has been achieved since SiC single crystals are In parallel with the rise of nanomaterial research and applica- now available in large sizes with extremely low defect concen- tions, interest in carbons as multipurpose materials has spiked trations and an almost atomically fl at surface fi nish. [ 8 ] in recent years.[ 1,2 ] One fi eld in particular has attracted atten- CDC applications as electrode materials in electric double tion: carbon materials for energy-related applications such as layer capacitors have attracted much attention lately. [ 9 ] The batteries, supercapacitors, fuel cells, and gas storage.[ 1 ] It is nec- unique properties of porous CDC obtained by halogenation, essary to understand the relationship between carbon structure such as a high specifi c surface area and tunable pore size with and the resulting properties to be able to tune and optimize a narrow size distribution, make it an ideal material for sorb- the carbon material to meet application requirements. With ents or supercapacitor electrodes. CDCs have been derived carbon materials existing in a variety of forms (amorphous and from many precursors (SiC, TiC, Mo C, VC, etc.) using a crystalline; sp2 and sp3 hybridization; porous and dense; fi lms, 2 variety of treatment conditions that lead to a broad range of particles, nanotubes, and fi bers) numerous applications are useful properties. Furthermore, graphene,[ 10 ] nanotubes,[ 11 ] possible,[ 2 ] but selecting the best material for a specifi c applica- and even nanodiamond[ 12 ] can be produced from carbide tion may be challenging. precursors. Their applications naturally differ from those of Porous carbons, fullerenes, nanotubes and, more recently, porous CDC. graphene are among the most widely studied materials. While The last comprehensive journal review on this subject was there are numerous methods of synthesizing carbon materials published about fi fteen years ago in Russian;[ 13 ] book chapters from gaseous, solid, and liquid precursors, their synthesis published later[ 3,4 , 14 ] are less accessible and require updating due to rapid progress in the fi eld over the past few years. [14] V. Presser , M. Heon , Prof. Y. Gogotsi The most recent review of CDC covers only energy-related Department of Materials Science & Engineering and A.J. Drexel applications. Therefore, a comprehensive review on the fi eld is Nanotechnology Institute long overdue. The goal of this article is to show how a variety Drexel University of carbon structures can be produced from carbides, to explain 3141 Chestnut St., Philadelphia, PA 19104, USA how those structures can be controlled on the nanometer and E-mail: [email protected] subnanometer scale, and to describe CDC properties that are DOI: 10.1002/adfm.201002094 benefi cial for a number of applications.

] 16 [ wileyonlinelibrary.com www.afm-journal.de received his received is Distinguished is a PhD student Volker Presser Volker the Eberhard Karls PhD from in Tübingen, Universität awarded Being Germany. Research Lynen the Feodor from the Alexander Fellowship von Humboldt Foundation, he joined Drexel University, Philadelphia, as a post- 2010. doctoral researcher in As the leader of the carbide- he derived carbons group, investigates the correlation Min Heon He at Drexel University. received his B.S. and M.S. degrees in Materials Science and Engineering from Pohang University of Science and (POSTECH) Technology in Korea and worked for as a Samsung Corning research engineer for eight years developing materials and devices related to LCD Gogotsi Yury University Professor Chair in the and Trustee Department of Materials Science and Engineering at He also Drexel University. serves as director of the A.J. Drexel Nanotechnology Institute. He received his MS (1984) and PhD (1986) degrees from Kiev Polytechnic and a DSc degree from C) and are not applicable to car- 2 or SiCDC. Since the latter two, however, the latter two, however, Since or SiCDC. ] 18 [ , or WC vs. W 0.5 Si-CDC, ] 17 [ C, TiC 4 between structure and properties of carbon nanomaterials. between structure and with display technologies. His research is concerned he explores new devices for electric energy storage and lms for application in patterned carbide-derived carbon ﬁ micro-supercapacitors. the Ukrainian Academy of Science in 1995. His current research is focused on carbon nanomaterials. carbon, for example, has been referred to as SiC-CDC, carbon, for example, has been referred to as SiC-CDC, bons derived from carbonitrides (e.g., SiCN) and other complex bons derived from carbonitrides (e.g., SiCN) will use the “pre- compounds, they should not be used. We terminology and recommend its use in future cursor-CDC” do not indicate the different stoichiometries of the precursor (e.g., B SiC-DC, SiC-DC, While ] 13 [ (a–g, j) and vacuum ] 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim GmbH & Co. 2011 WILEY-VCH Verlag , 5 4 © [ Copyright 2008-2010, Elsevier. 2008-2010, Elsevier. Copyright ] Copyright 2006, CRC Taylor & Francis. & Francis. 2006, CRC Taylor Copyright ] 4 [ 5–7 [ (h–i). Amorphous porous carbon (a), turbos- ] or “nanoporous carbons” (NPC). or “nanoporous carbons” , 810–833 ] 6,7 [ 21 15 [ , 2011

Transmission electron microscopy images of various CDC electron microscopy images of various Transmission ect the variety of carbon structures present in the CDC ect the variety of carbon structures Figure 1 . structures as obtained from carbide chlorination Over the years, different terms were used for CDCs, such as Over the years, different terms were used for CDCs, such “mineral carbons” 2. Nomenclature tratic carbon (b), fullerene-like carbon (c), nano-diamond (d), onion-like carbon (e), carbon nano-barrels (f), mesoporous carbon (g), carbon nanotubes (h), epitaxial graphene (i), graphite (j). The scale bar is 5 nm. Reproduced with permission. Reproduced with permission. decomposition of SiC the former has been out of use for a long time, the latter does not refl family and does not differentiate between CDC and an acti- In recent vated or template carbon with nanoscale porosity. years, most studies refer to CDC using a nomenclature that carbide-derived Silicon clearly indicates the carbide precursor. www.MaterialsViews.com Adv. Funct. Mater. Funct. Adv. FEATURE ARTICLE 812 disordered porouscarbon)and absenceoforganicresidues, in termsofstructure(chlorination usuallyproducedhighly later realizedthatporousCDCwasanewclassofcarbon. large-scale synthesisofSiCl The noveltyandthename“mineralcarbon” reported methodofproducingCDC. bide, originallypatentedbyOtisHutchins in1918,wasthefi ambient pressureformanycarbides.Chlorinationofsiliconcar- reported atelevatedtemperatures(typicallyabove200 Selective extractionofmetalatoms fromthecarbidelatticewas 3.1.1. HistoricPerspectiveandCarbide Precursors Halogenation 3.1. lowing sections. carbon formationandtheywillbediscussedindetailthefol- position arethemostcommonchemicalreactionsleadingto via halogenation,hydrothermaltreatment,andvacuumdecom- ganic salts;however, chemicalextractionofthemetalatom(s) ferent methods,includingacidetchingorreactionswithinor- approach, respectively). the fi fi other carbon-formingprocessesusedformanufacturingcarbon vacuum annealing.WhileCDCgrowsintothesubstratecarbide, be removedbysubsequenttreatmentsuchashydrogenationor ucts (e.g.,metalchlorides)aretrappedinthepores,theycan and volumeoftheprecursor. Iftheremainingreactionprod- inward growth,usuallywiththeretentionoforiginalshape ture intopurecarbon.Inthisway, thecarbonlayerisformedby the metalormetalloidatoms,transformingcarbidestruc- aspect incommon:carbonisformedbyselectiveextractionof production ofCDC.AllCDCsynthesismethodshaveone has becomeoneofthekeysyntheticmethodsforlarge-scale for CDCsynthesis.Halogenation andespeciallychlorination Several chemicalreactionsandphysicalprocessescanbeused 3. CDCSynthesisandStructure the nomenclatureOM-CDCwasintroduced derived fromorderedmesoporous(OM)carbideprecursors, type, suchasPDC-CDC(polymer-derived ceramics).For CDC can alsobeusedforamoregeneraldescriptionofprecursor publications asthemostdescriptiveterm.Thisnomenclature and notjusttheresultingstructure. term, likeOM-SiC-CDC, whichclearlyindicatestheprecursor byproduct ofSiCl conductor industry. Initiallyregardedasmerelyanundesired dantly availableasaresultoftheadventmodernsemi- modifi Slightly OM-SiC. ride andresidualcarbonwasobservedfollowing Equation 1 : carbide todrychlorinegas,theformationofsilicontetrachlo- wileyonlinelibrary.com www.afm-journal.de SiC(s) lms (chemicalorphysicalvapordeposition:CVD,PVD) coat CDC canbeformedfromcarbideprecursorsbymanydif- lm ontoanexistingsubstrate(bottom-upversustop-down + [ 2Cl 20 ] Inthisregard,wesuggestusingamorespecifi 2 (g) ed in1956, → 4 synthesisproducedintonquantities,itwas SiCl 4 (g) [ 22 4 ] + beforepuresiliconbecameabun- thisprocesswaswidelyusedfor C(s) (1) [ 21 ] By exposinghotsilicon © 2011WILEY-VCHVerlag GmbH&Co. KGaA,Weinheim [ [ 19 15 ] ] inanalogyto werejustifi ° C and C) rst ed [ 15 c ]

hydrogen gas.From theexperienceoflarge-scaleSiCl metal chloridescanberemovedbyannealing,forexample,in unlike thatinactivatedcarbon.Remainingresidualchlorineor Ti Ti and bothmicro-nanometer-sized powders, Ti carbide, alongwithcarbon. solid reactionproducts,namelysiliconcarbideandtitanium we mustbeawarethatpartialchlorinationmayyieldmore Cr Mo by sintering, via halogenationofsuchprecursors:ceramicbodiesobtained used forCDCsynthesis:Al reaction products. high meltingpoint( yields bothgaseousMCl manufacturing commercialquantitiesofcarbonperyear. it isclearthatCDCsynthesisprocesscanbeeasilyscaledupto Si Si must bewritten.For example,whenconsideringTi ally carriedoutatmuchhighertemperatures. range ofinterest: XeF (120 for otherbinarycarbidesanddifferenthalogens carbides suchasferrocene(Fe(C a moregeneralreactionequation: trations inceramicmaterials. presence ofsinteringaidsand highdefectorimpurityconcen- crystals orthinfi mation. Theuseofhigh-puritymaterialsintheformsingle out andhavegreatlyenhancedourunderstandingofCDCfor- available, anumberoffundamentalstudieshavebeencarried as singlecrystals. fi identifi shown toetchalargenumberofcarbides(Al M orahalogen-containingetchant(e.g.,HCl,HF),and thereof) carbide-nitride composites,suchasZrC/ZrN CDC nanostructureswerealsoreportedfor, e.g.,carbonitrides, technique andtemperaturesasforcarbidechlorination,porous single crystals from carbides found tobeveryaggressive,eitherproducingfl MC(s) x lms. · 3 3 2 x

3 Many kindsandshapes ofCDCmaterialshavebeenformed A largenumberofbinaryandternarycarbideshavebeen For manybinarycarbides(e.g.,M For ternarycarbides,morecomplexreactionequations Fluorination withF where Aisagaseoushalogen(F The carbonformationbyselectivecarbideetchingispossible N SiC A MC(s) AlC. C 2 2 C, MoC,Nb y 4 2 etching,offeringamethodoflow-temperaturesynthesis ° agaseousreactionproduct. [ , Fe , [ 5 C) 32 2 ed asasolidreactionproduct. ] + orcarbonandmetalcontainingsubstancesotherthan , TiC, VC,W [ ] 34 Non-ﬂ [ 32 2Cl 3 ] + C, SiC, ThC Somemetalchlorides,forexample,CaCl ] asanalternativetoSiC chlorination,whichisusu- 2 y [ 62 (g) [ [ 2 uorinatedSiC-CDC wasdescribedinthecaseof 31 64 ] orhot-pressing, 2 · ] ] orleadingtothedisintegration ofSiC thin → andhigh-qualitycarbidethinﬁ C, NbC,SiC, SrC [ lms eliminatescomplicationscausedbythe A 23–25 [ 61 2 (g) 2 ] MCl T C, WC,andZrC. With large,highqualitysiliconcarbide ]

2 2 , TiC, UC , orwithamilderagent(e.g.,CoF

→ = 4 4 782 andsolidcarboninthetemperature (g) M 4 C + [ x 33 A 3 ° C(s) , B , ] y Thesamewasdiscussedfor C) andmaybepresentassolid [ 2 5 24 (g) , WC)andﬂ H ] 4 2 whiskers, C BaC C, , Ta , 5 Adv. Funct. (2) + ) 2 2 [ , Cl , 31 ). [ x 18 = 2 [ ] 59–61 · C, TaC, Ti Directﬂ Si, Ti, Zr), Equation 2 , 23 C(s) 2 www.MaterialsViews.com , , Br , 2 33–58 , CaC , ]

Mater. uorocarbonswere [ (3) 30 [ 4 2 ] ] , I , Usingthesame ]

thinﬁ 4 uorination was [ 26–30 C 2 [

lms 2 29 2 2011 , Cr , [ 3 , ormixtures 15 AC Ti AlC, uorocarbons , B , , 42 ] andSiC/ ] 4 leadingto , , 3 45 synthesis, [ lms, 4 65 21 C 2 C CaC C, , havea ] aswell ] 2 , 810–833 widely , Fe , 3 3 ) was ), 3 AlC [ SiC 41 3 , C, 63 2 2 2 , , ]

FEATURE ARTICLE 813 1200 1200 1200 m thick- (g) μ Cl Range III Range 1000 1000 1000 wileyonlinelibrary.com www.afm-journal.de Range III (g) 4 800 800 800 SiCl °C / Range II ) ow of chlorine-containing gas, ow of chlorine-containing s ( C ) (g) s 4 erature ( (g) p 4 C CCl 600 600 600 CCl ) s ( Range II C lms up to approximately 50–100 (g) (g) 2 4 ) s Cl ( SiCl indicating a reaction-controlled mechanism indicating a reaction-controlled SiC ] 400 tem Chlorination 400 400 which obeys a parabolic growth law for layers thicker which obeys a parabolic ] 69,70 , a). This is in contrast to oxidation of, for example, silicona). This is in contrast to oxidation 71 [ for porous ﬁ ) ] l ( 26,27 68 4 [ , 25 [ While thermodynamic calculations provide valuable infor- (g) Range I Range ) 4

l SiCl k Figure 3 Figure ness, than 2 nm after an initial linear growth phase. The linear growth mation on CDC formation under equilibrium conditions in a closed system, the typical apparatus for carbide chlorination is an open system in which gaseous reaction products are con- tinuously removed in a steady ﬂ right and favoring carbon forma- to the Equation 3 shifting tion. Thus, thermodynamic calculations should be considered as a guideline suggesting that maximum yield of carbon can be observed at moderate temperatures for moderate chlorine- to-carbide ratios. 3.1.3. Reaction Kinetics CDC growth can usually be described with a linear growth rate ( ( carbide, 200 200 200 :SiC = 5:1 5:1 = :SiC ) :SiC1:1 = :SiC = = 20:1 :SiC SiCl ) l 2 l 2 2 ( ( ) Range I 4

4 l ( χ

4 SiCl CCl and ] c) Cl a) Cl a) b) Cl SiCl Thermodynamic calculations for the chlorination of silicon carbide with different Thermodynamic calculations for the chlorination of silicon 51 [ 0 0 0 0.00 0.00 2.00 1.80 1.60 1.40 1.20 1.00 0.80 0.60 0.40 0.20 0.00 1.80 1.60 1.40 1.20 1.00 0.80 0.60 0.40 0.20 2.00 1.80 1.60 1.40 1.20 1.00 0.80 0.60 0.40 0.20 2.00

Equilibrium amount / mol Equilibrium amount / mol mol / amount Equilibrium mol / amount Equilibrium Equilibrium amount / mol mol / amount Equilibrium Figure 2 . of 1:1 (a), 5:1 (b), and 20:1 (c). carbide to chlorine ratios. Chlorine to carbide ratio

] 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim GmbH & Co. 2011 WILEY-VCH Verlag ). and carbon forma- , corresponding to a 66 4 © [

χ , or 4 and ] 3 [ Figure 2 Figure , as either , TiCl 2 cance are 4 TiC, ] ) is recycled C ( 4 33 ° [ AlC, 2 Ti ] 34 . , 810–833 [ 4 , In the low temperature range I, no CDC ] 2 21 is possible even at room temperatures where ] , . From calculations, it is evi- calculations, . From 51 [ 34 χ

[ AlC 3 2011

, because hydrolysis of titanium Ti ] 4 67 , 3 has been reported and has helped to [ ] ) produced along with CDC. There is ) produced 5 51 [ . At moderate temperatures, both CCl . At result in unreacted carbide or in decreased yield because of result in unreacted 4 For CDC formation, we can identify three different tem- CDC formation, For Chlorination is the most economic and most economic and is the Chlorination

χ shift the onset of range III to high temperatures and low values of formation is predicted because of the preferred formation of CCl the presence of CCl for photocatalytic and other applications. for photocatalytic and other applications. Reactions 3.1.2. Thermodynamics of Carbide with Halogens of chlorination Thermodynamic analysis of SiC, ternary carbides perature ranges. ZrC dent that the halogen species must be present at an excess amount to produce carbon etc.) even at SiC, without residual solids (TiC, temperatures as high as 1200 It was also suggested that carbon formation from binary scalable method for CDC synthesis. Two com- Two for CDC synthesis. scalable method Philadelphia, (located near panies, Y-Carbon in (located Skeleton Technologies USA) and CDC as their main Estonia) produce Tartu, process of scaling up product and are in the of other compa- the production. A number CDC as a byproduct produce nies, however, Production costs of metal chloride synthesis. when chlorination is can be further reduced system in which performed in a closed-loop (e.g., TiCl the reaction product understand what kind of reactions can lead understand what kind of reactions can to carbon formation, and the effect of tem- the perature, pressure and concentration on formation of carbon. The two most important factors of thermodynamic signifi the treatment temperature and the chlorine- to-carbide ratio, tion can be observed (range II). In the high temperature range III, solid carbon is the only stable carbon-containing reac- an increased chlorine to carbon ratio, the tion product. With onset of carbon formation and maximum carbon yield (range those calculations, it is III) shifts to higher temperatures. From clear that there is an optimum value for carbon is not the only solid phase in the reaction (Figure 2 a) 2 carbon is not the only solid phase in the reaction (Figure and a high content of unreacted carbide is present. tetrachloride is the most common commercial route to the synthesis of TiO large range over which a maximum yield of pure carbon as the values for only stable reaction product can be observed. High and turned back into metal carbide, such as and turned back into can also be lowered by uti- The costs TiC. (SiCl lizing high-purity chlorides MoCl a high demand for these chlorides, especially TiCl nanometer or micrometer-sized particles, nanometer or micrometer-sized www.MaterialsViews.com Adv. Funct. Mater. Funct. Adv. FEATURE ARTICLE 814 iue 3. Figure duced withpermission. for ashorttimeandatlowtemperatures,linearkineticsareobserved.For thickerCDCfi lms, theparabolictimelawisclear 1.04 wt%Cl a signifi for chlorinationat1000 a linearregression(Figure 3 b) uptoapproximately80

tion becomesnarroweratlowertemperatures. nius temperaturedependency, thelinearregimeofCDCforma- possible tofi [ work fortheoutwarddiffusionofSiCl (see section2.1.4).Micropores( of CDCfi diffusion-controlled mechanismhavebeenreported. ear–parabolic Deal-and-Grove-like growthkinetics indicatinga In thisway, carbidefi wileyonlinelibrary.com www.afm-journal.de 51 ] canbecompletelytransformedintoCDCbyhalogenation. I steady-fl In For thickerCDClayersandlongerhalogenation times,lin- cant infl cant b) Growth kineticsofCDCfi lmsduring chlorination ofTyranno SiCfi bers lms resultsfromthehighporosityofCDClayer a) 2 t theCDCfi ow chlorination, thegasfl ). [ 45 uence onthehalogenationrate.Orekhovetal. before after before after ] With thediffusionkineticsfollowinganArrhe- [ bers, 69 ] Copyright 2003,JohnWileyandSons.Panel(b)reproducedwithpermission. 5 µm 10 µm ° lm growthdatareasonablywellwith C andupto50 SiC [ 69 , 72 < ] fi CDC 2 nm)provideanaccessiblenet- lms, ow rate was shown to have ow rate wasshowntohave [ 73 ] plates, 4 molecule (0.568 nm). μ © m at900 2011WILEY-VCHVerlag GmbH&Co. KGaA,Weinheim [ 74 ] andpowders CDC layer thickness / µm CDC layer thickness / µm [ 49 ° 100 150 200 250 300 350 0.0 0.5 1.0 1.5 2.0 2.5 C (Ar , 69 50 ] 0 Itis ...... 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0

μ 10203040506070800 [ m 25 + ]

concentration followingaLangmuir–Hinshelwood equation. where theconversionratewasfoundtobeafunctionofchlorine agreement witharecentstudyonTiC-CDC formation kinetics rates and/orlongerchlorinationtimesthanthinfi packed thicklayersofcarbidepowdermayrequirehigherfl chlorination apparatusandthesampletype.For example,densely to drop.Thechlorinationratealsodependsonthegeometryof atmosphere nearthecarbidesurfacecausingchlorinationrate Figure 2 : adecreaseinthechlorinegaspressurecreateslocal can beexplainedbythethermodynamiccalculationspresented in factor of2intheCDCrateatvaluesbelowthat.Thechange values ( sible tocontroltheCDCfi with awell-calibratedtemperature andtimedependency, itispos- The mostimportantaspectofCDCformation,however, isthat determined thechlorinationrateofZrCandfoundconstant linear 550 °C 650 °C 700 °C 900 °C 1000 °C [ 69 ] inpureCl ± 5%) above k Chlorination time / h l = 1.426 µm/h Chlorination time / h / time Chlorination 2 (a)andsintered linear-parabolic ∼ 6mm/sgasfl lm thicknesswithhighaccuracy. [ 45 ] Copyright 2006,InstituteofPhysics. α -i -SiC ow and an abrupt decrease by a ow andanabruptdecreasebya k [ Adv. Funct. l 45 k = 0.545 ] l inAr = 0.007 ly visible.Panel(a)repro- www.MaterialsViews.com +

3.5%Cl Mater. µ m/h µ m/h lms. Thisisin

2011 2 (b).Asseen, , 21 , 810–833 ow ow [ k 68 l

- ]

FEATURE ARTICLE 815 200nm 200nm 200nm 200nm c surface Conformal ] to form mes- Copyright 2006, Copyright ] 4 30 [ 78,79 wileyonlinelibrary.com [ www.afm-journal.de or polymer-derived or polymer-derived ] 72 [ C (c). Shape and size of the ° ) is characteristic of CDC 1 [111] [111] − The bulk porosity of CDC is ] g 37 2 , 9 , and 3C-SiC. Figure 5 shows that 5 Figure and 3C-SiC. CDC CDC 2 CDC -SiC -SiC 3–5 -SiC [ β β SiC SiC 50 vol%) with a high speciﬁ 3 > C (b) and 1200 as precursors. While net shape and size as precursors. ] ° 5 [ This mesoporous TiC also undergoes conformal This mesoporous TiC ] 78 [ TEM (a–c) and SEM (d) images showing a comparison of TEM (a–c) and -SiC) whiskers at various stages of chlorination: as received β The conformal carbide-carbon transformation can also be The c) d) a) a) b) The American Ceramic Society. Society. The American Ceramic Figure 4 . 3C-SiC ( (a), chlorinated at 700 initial whisker are largely maintained after silicon carbide halogenation initial whisker are largely maintained after silicon and c originate from the (d). The diagonal structures seen in Figure 4b TEM grid (lacey carbon). Reproduced with permission. area (SSA more than 2000 m obtained via halogenation. observed when using polymer-derived carbides (PDC), such as carbides (PDC), such as observed when using polymer-derived polycarbosilane-derived silicon carbide largely determined by the carbide structure. When metal atoms are extracted from the carbide lattice, the remaining carbon forms microporous CDC structures. This is schematically illus- for Ti 5 trated in Figure transformation into carbon allows CDC formation to be carried producing metal carbides coated with carbon that out partially, have catalytic, tribologcial and other applications. c Size Distribution (PSD) and Speciﬁ Pore 3.1.5. Porosity, Surface Area (SSA) A high bulk porosity ( oporous TiC. oporous TiC. silicon carbonitride, the precursor and changes can be observed when comparing changes result from the material after pyrolysis, only minimal carbon is a spe- subsequent halogenation. Biomorphic porous cial form of template that can be obtained from carbonized paper and readily reacts with methane and TiCl differences in the distribution of carbon atoms in the carbide lattice lead to a major change in the resulting CDC structure. transformation to CDC upon chlorination.

] 1 1 ). ). ] − − ] C. C. C) 77 [

° ° ° ] 76 75 [ [ 69 [ C ° C, and C. ° ° Although ] 33 [ ). 144 kJ mol at 1000 lms, crack for-

= 2 0.5

was reported by

a 1 N E − C and 750 uorine partial gas 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim GmbH & Co. 2011 WILEY-VCH Verlag C) was found. This C) was found. ° 0.5 ° © C). A similar but less ° 75 vol%), a partial col- 75 vol%), a rst reported for TiC rst reported for TiC > AlC 2 C. For TiC under the same TiC C. For diffusion in silica glass diffusion -SiC precursor is gradually -SiC ° 2 β This conformal transforma- ] addition to Cl (650–900 2 30 1 [ − for O of CDC formation can be calcu- 1 between 600 a

− 1 E −

of ZrC was reported uorination rate where a C and 980 ° is seen in the data presented by Zelikman is seen in the data presented by Zelikman

, 810–833 ] a

E 27 21 [ A recent transmission electron microscopy ] , of 23 kJ mol Figure 4 Figure -SiC -SiC whiskers.

a in the temperature range between 400–800 in the temperature range 43 β ] [ E a) in which the density of carbon atoms is lower. a) in which the density of carbon atoms is lower. 23 2011 [

are in the range of typical diffusion-related activa- This phenomenon was fi AlC) and carbonitrides, (Ti AlC) and carbonitrides, (Ti ] 1 2 between 750 − 1 − 69,70 , Ti [ 2 for WC: 153 kJ mol Figure 5 Figure ] 49 [ uorination of ZrC and HfC in the range of 300–900 uorination of AlC 3 Due to their extremely high porosity ( Due to their Changing the halogen concentration in the gas phase will concentration in the the halogen Changing When performing carbide halogenation at different tempera- When performing -axis ( lms or for manufacturing thick free-standing CDC plates from could be explained in terms of reaction control: at higher tem- could be explained in terms of reaction control: by the predomi- peratures, the lower activation energy is caused to linear kinetics), nance of the reaction itself (corresponding is diffusion- while at lower temperatures CDC formation above Values controlled (corresponding to parabolic kinetics). 100 kJ mol tion is shown in consumed by the forming CDC layer until the entire whisker has been fully transformed. for the parabolic CDC layer growth on SiC at 900–1000 for the parabolic CDC layer growth on SiC for fl energy was reported conditions, no such change in the activation and a constant of This is corroborated by the reported value lapse of the carbon structure and resulting cracks were reported for micrometer sized powders of CDC from ternary carbides (Ti (TEM) study on CDC synthesis showed that the net shape of even a complex shaped carbide precursor is maintained after chlorination of mation or structural collapse may occur for CDC with a porosity larger than 68–74 vol%, as predicted by the structural stability et al. criterion of highly porous ceramics calculated by Pabst certain carbides. For refractory bodies or thin fi certain carbides. For 3.1.4. Conformal Carbide-to-Carbon Transformation by carbide halogenation typically main- CDC formation the carbide precursor tains the original shape and volume of transformation and is, therefore, referred to as a conformal process. largely conformal, some shrinkage was observed along the a This phenomenon is a limitation for CDC synthesis from thin fi lated using an Arrhenius equation. For the chlorination of TiC chlorination of TiC the equation. For lated using an Arrhenius energy of 50 (38) kJ mol (NbC), an activation also result in a different CDC formation rate. For example, formation rate. For in a different CDC also result to slow gas was shown to pure chlorine adding hydrogen considerably (a chlorination SiC net reaction rate of down the 22% for every 1% H decrease of Kirillova et al. et al. 42 kJ mol tion energies (e.g., 113 kJ mol Kuriakose et al. calculated an activation energy of 92 kJ mol et al. calculated an activation energy of Kuriakose tures, the activation energy tures, the activation powder where grain size and shape did not change as a result of chlorination. drastic decrease in to a very low value of 10 kJ/mol (650–950 to a very low value of 10 kJ/mol For ZrC chlorination at higher temperatures, there is a large ZrC chlorination at higher temperatures, For (450–650 kJ/mol decrease in the activation energy from 62 Additionally, a direct relation between the fl a direct relation between Additionally, fl pressure and the resulting et al. by Kuriakose www.MaterialsViews.com Adv. Funct. Mater. Funct. Adv. FEATURE ARTICLE 816 with permission. iue 5. Figure obtained fromNLDFT. pore sizedistribution,theternarycarbideshowsabroaderdistributionthanbinaryat1200 SiC CDCstillconsistsofpredominantlyamorphouscarbon,Ti and Ti a largedifferenceintheorderingofCDCobtainedfromSiC functional theory: NLDFT; Ar-sorption). Furthermore, thereis

4.9 gcm ρ pore volume for Ti and abroaderrangeofporesizesbetween0.54nm a narrowdistributionofporesizesbelow1nmfor3C-SiC a largedifferenceintheresultingporesizedistributionwith At thesamesynthesis temperature(e.g.,1200 0.51 cm (approximated tobe2.2gcm bide (e.g.,forSiC: with wileyonlinelibrary.com www.afm-journal.de V carbide total It ispossible tocalculatethetotalweight-basedtheoretical X = 3 thedensityofcarbideprecursor(e.g.,TiC: 3 SiC carbon

SiC 3 Schematic oftheatomicstructureTi X − g 3 2 carbon 2 ). For siliconcarbide, basedongasadsorptiondata(non-localdensity . − beingtheweightfractionofcarbonincar- 1 V , whichisinagreementwithliterature. [

] Also,weseethatforthesamechlorinationtemperature(1200 −

= D 0.30), carbon 1 − 3 , thedensityofgraphite),and (4) V ρ

total

carbide 3 [ SiC 39 ] For 2 CDCshowssigniﬁ cant graphitizationatthesametemperature.

(due toCl 50–90 vol%.Thus,highlyporouscarbonswithopenporosity expect CDCbulkporositywithintherangeofapproximately for theCDC.Basedonchoiceofcarbideprecursor, wecan titanium carbide,thisyieldsanetporosityofabout57vol% IV adsorptionisothermwitha characteristic hysteresisloopdue mesostructured carbideprecursors (OM-CDC) a largetotalspeciﬁ from alargenumberofcarbideprecursorsandCDCalsohad This adsorptionisothermtypewasconﬁ studies byBoehm size distribution(PSD)isafunctionofthetemperature.Early over awiderangeofhalogenationtemperatures,thepore activation steps. between 500and1900 carbon producedusingatemplatingapproach, poly(methylvinyl)silazane asaprecursor, oporous CDCobtainedfrompolymer-derived ceramicswith adsorption isotherms, While thebulkporosityofCDCremainslargelyunchanged ° 2 C) theresultingcarbonstructurecanbeverydifferent–while / MCl / x

transport)canbeproducedwithnoadditional c surfaceareaofupto2800m [ 37 ] onCDCformationfromTaC andSiC [ 80 ° ] anindicationofmicroporouscarbon. C showedcharacteristictypeIN ° C. Thedataarefromargonsorption Adv. Funct. rmed forCDCobtained [ 5 www.MaterialsViews.com ] orderedmesoporous

Mater. [ 82,83 [ [

4 81 2011 , 24 ] showatype ] orordered ] 2 Reproduced g , 21 − , 810–833 1 . Mes- . 2 gas FEATURE ARTICLE 817 Thus, ] 86,87 , 53 , 51 For many car- For , ] 46 wileyonlinelibrary.com 85 , www.afm-journal.de [ 33 [ ). The pore size distribu- ] 86 [ Comparison between the PSD of Comparison Figure 6 Figure ] 86 [ Broad, yet highly temperature- Broad, yet highly . ] 2 showed that, in PDC SiCN-CDC showed that, in PDC SiCN-CDC 4 ] [ 5 [ SiC 3 Ti ] 51 [ nd a direct correlation between the halo- correlation between nd a direct ZrC, ] 53 [ VC, ] 33 [ AlC, 2 Ti ] At higher temperatures, there is an increase in pore size an increase in there is higher temperatures, At 46 [ , 3 tion displayed in Figure 5 b and 6b is even narrower than for b 5 tion displayed in Figure single-wall carbon nanotubes. bide precursors, we ﬁ bide precursors, smaller resulting pore size with and the genation temperature ( pore sizes at lower temperatures the pore size is possible by controlling additional tuning of the synthesis temperature gives the temperature. Changing size control with sub-Ångstrom accuracy a high level of pore to b, demonstrating why CDC is referred 6 as shown in Figure porosity. as a material with tunable sensitive pore size distributions can be found for PDC-CDC, as can be found for PDC-CDC, sensitive pore size distributions et al. c. Yeon 6 seen in Figure due to self-organization and higher carbon mobility along with higher carbon mobility and due to self-organization material. crystallinity of the carbon increased materials, micropores are formed by etching Si atoms from atoms are formed by etching Si materials, micropores are a result of the elimination phase and mesopores the SiC porosity then strongly regions. The resulting hierarchic of Si-N C 4 C, with 2 chlorin- 3 This uni- ] C 4 84 , 57 , 42 , 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim GmbH & Co. 2011 WILEY-VCH Verlag 39 [ © and SiC precursors are precursors are and SiC 2 (c) from nitrogen sorption using NLDFT. (c) from nitrogen sorption using NLDFT. ] 5 SiC SiC [ 3 C) was reported to show a type reported to show C) was C or orthorhombic Mo C or orthorhombic Mo ° 4 , 810–833 21 , -CDC and narrow PSD for SiC-CDC. -CDC and narrow PSD for SiC-CDC. 2 2011

] (b) and SiCN PDC-CDC ] SiC SiC 46 [ 3 86 [ Average pore sizes for selected binary and ternary carbides (a): Al Average -CDC 2 adsorption isotherm due to microporous carbon whereas due to microporous adsorption isotherm 2 Typically, CDCs pore size and PSD are templated by the by the CDCs pore size and PSD are templated Typically, SiC 3 Figure 6 . Ti I N ated at a low temperature (300 temperature (300 ated at a low higher temperatures resulted in mesoporous CDC and type IV mesoporous CDC resulted in higher temperatures adsorption. to condensation in the mesopores. For example, Al example, Al For in the mesopores. to condensation a large and non-uniform nearest neighbor separation, show a a nearest neighbor separation, show a large and non-uniform after chlorination. wider PSD of the CDC can clearly synthesis temperature. We compared at the same intrinsic broad see the trend and the differentiation between PSD for Ti carbide precursor crystal structure at low temperatures. crystal structure at low temperatures. carbide precursor VC, ZrC) or (e.g., TiC, with the NaCl structure Carbides pore yield a narrow structure (SiC) würtzite/zinc blend neighbor separation is uniform the first size distribution as b). Rhombohedral B 5 (Figure form nearest neighbor separation is depicted in Figure 5 b, b, 5 separation is depicted in Figure form nearest neighbor from Ti where the PSD obtained www.MaterialsViews.com Adv. Funct. Mater. Funct. Adv. FEATURE ARTICLE 818 another molecule,e.g.,H would bethesamesurfaceareaaccessibleforsorptionof temperatures of800–1000 This explainswhythereisamaximumSSAatintermediate at hightemperatures,graphitizationandCDCconsolidation. peratures, cloggingofporeswithhalogenideresiduesand, than assumethattheSSAmeasured(e.g.,viaN optimal specifi 1 nm,smallerthancertainmolecules,itisbettertofi activation couldbe.Furthermore, whenporesizesarebelow what themaximumvalueforaporevolumewithoutadditional to thepresenceofporessmallerthan0.5nm. volumes, andspecifi and theresultingvaluesofporesizedistribution,total are notaccessibleformostgasspeciesusedadsorption decrease butsignifi pores smallerthan0.5nm),thecorrespondingSSAshouldnot temperatures, poresaretemplatedbythecarbidelattice(i.e., bulk materials.Consequently, powdersreactmorereadilyto we fi face ofcarbideparticles.With powders(especiallynanopowders) as wellonetchingconditions(Figure 6 c). depends onpyrolysistemperatureofthepre-ceramicpolymer chlorination times, non-planar graphiticcarbon.At lowertemperaturesorshorter at around1000 there isaconstantincreaseinstructuralorderwiththreshold example. Startingwithhighlydisorderedamorphouscarbon, from chlorinationofTiC atdifferenttemperaturesasatypical Figure 7 The structureofCDCalsodependsontheseparameters. depend onprecursorandhalogenationtemperatures. As discussedbefore,poresize,PSD,andSSAoftheCDC Structure Carbon 3.1.6. ence. SSA wasreportedtohaveabell-shapedtemperaturedepend- ceramic precursorandtemperature.For manymaterials,the to removechlorine-containingresidue. pronounced forVCwhenthoroughannealingisperformed wileyonlinelibrary.com and 1200 7. Figure www.afm-journal.de With veryhighvaluesfortheSSAofCDC,itisnotclear Te specifi The nd ahigherreactivityduetotheSSAcompared [ 42 , 51 ° Simulated structureofTiC-CDCobtainedafterchlorination at600 showsthestructuralevolutionofCDCobtained ] C; slowquenching(C). LimitingfactorsfortheSSAinclude,atlowtem- c surfacearea(SSA)changesasafunctionof c surfaceareaforaparticularapplicationrather ° C, wherethestructurebecomesdominatedby cantly increase.However, suchsmallpores [ 30 c surfaceareamaybeunderestimateddue ] amorphouscarbonisfoundonthesur- 2 . ° C. [ 88 [ 42 ] Reproducedwithpermisssion. , 51 ] Thebellshape ismuchless [ 53 ] Given that,atlow ©

2011WILEY-VCHVerlag GmbH&Co. KGaA,Weinheim 2 -a sorption) -gas nd the [ 88 ] Copyright 2010,Elsevier. an increaseinthecoordinationnumber(Figure 7). trend ofhighershort-rangeorderattemperaturesand of H neutron scatteringexperiments, crystallinity withchangingtemperature.Inagreement ulate thestructureofdisorderedcarbonandevolution form amorphousordisorderedporousCDC. formation. StudiesonAr-Cl the chlorinationofcarbides(Figure 1 ). structures andevenfullerene-likemaybefoundafter spherical graphiticshells),nanodiamond,nanotubes,barrel-like different nanostructuressuchascarbononions(i.e.,concentric mission electronmicroscopy(TEM)studieshaverevealedthat nanostructures thathavebeenobservedforCDC.Infact,trans- tures formduringhalogenation,therearemanyothercarbon (Figure 1 b). Whileamorphouscarbonandgraphite-likestruc- evolving graphiteribbonsathigherhalogenationtemperatures at alowtemperatureandincreasinglycrystallinecarbonwith phous (Figure 1 a,b) orhighlydisorderedcarbonifproduced ture. CDCisoftenunderstoodandusedasatermforamor- rination aremorevariedthangenerallydepictedinthelitera- carbon networks. also increasetheaccuracyofpredictingtransportinporous CDC. Theymustaccountforsurfaceterminationwhichwill are neededtogainabetterunderstandingofdisorderedporous surface areacanbeexpected.Moreadvancedmodels,however, that evolvesreducestheporesandacorrespondingdropin sponding toslowquenchratesforQMD)thestructuralorder At highchlorinationtemperatures(experimentaldata;corre- ical agreementwithHR-TEMstudiesofthesamematerial. could beusedtoreproducestructuresthatwereinmorpholog- characteristic d-spacingof temperatures, graphenesheetsandgraphiteribbons niﬁ peratures, suchas600 tion tospectroscopyevidence,TEMimages troscopy andelectronenergyloss(EEL)spectra. same timenanodiamondwasobservedfromRamanspec- showed diamond-relatedlatticefringes,andnanoindentation reverse MonteCarlo (RMC)simulations ° C, whichcorrespondstofastquenching(A),800 The choiceofreactiongasmixturestronglyinﬂ Nanostructures foundinCDCobtainedfromcarbidechlo- Recently, quenchedmoleculardynamics(QMD) cant increaseinthecrystallinity of thematerial.At higher 2 to thegasmixturereducedreactionrate,butat ° C forSiC chlorination,thereisnosig- < 2 3.4 Åareformed. mixturesrevealedthattheaddition [ 88 ] modelingshowedthesame Adv. Funct. [ 89 www.MaterialsViews.com ]

wereusedtosim- Mater. [ 18 °

C; mediumrate(B), [ , 48 91 ] ] At lowertem- ofCDCﬁ

2011 [ 70 uences CDC uences , 90 , [ ] 48 [ 21 Inaddi- 88 [ ] 88 , 810–833 witha ] QMD ] and lms [ 88 ]

FEATURE ARTICLE 819

] 3 C. ° ected 102,103 [ C ° were used were used 2 cial properties in the chlorine in the chlorine , can chemically wileyonlinelibrary.com 2 www.afm-journal.de 3

] It is important to ] 36 109 [ [ , other reactive pro- TiO 3 ] 101 In particular, ammonia In particular, [ ] C and pressures of up to Post-synthesis annealing Post-synthesis ° ] and NH 36 [ 2 24 [ cation of the pore structure cation of the pore structure or NH 2

] 99 [ resulted in larger surface area, and resulted in larger surface area, and ] chlorination and cooling in chlorine chlorination 2 104 [ The term hydrothermal refers to hot,

] and bulk materials. ] It is important to choose post-synthesis It is important SiC SiC ] 3 Both gases, H Both gases, 44 ] [ equilibrium. As a result, pore coarsening equilibrium. As a result, pore coarsening

105,106 2 [ 100 107,108 [ , 12 [ bers. bers bers annealing at the same temperature. rst reported in the early 1990s for amorphous Si-Ti-C-O rst reported in the early 1990s for amorphous Si-Ti-C-O 2 annealing, for instance, was reported to improve hydrogen Apart from treatment in H from treatment Apart The importance of annealing conditions is also refl The c surface areas. c surface 2 ow, it is obvious that chlorine removal via post-synthesis chlorine removal via post-synthesis it is obvious that ow, atmosphere was used to controllably oxidize some of the cre- atmosphere was used to controllably oxidize ated CDC and additional modifi or by control- was obtained by adjusting the temperature ling the CO–CO react with chlorine leading to HCl formation. The latter can be The latter can be react with chlorine leading to HCl formation. its smaller molecular easily removed from pores because of diameter. the properties of cedures have been reported to improve 10 wt% TiO with CDC. Mixtures of 90 wt% TiC hundreds of MPa. Studies were later expanded to pure silicon hundreds of MPa. carbide fi high-pressure (usually supercritical) water at typical temperatures in the range of 200–1000 treatment is important for CDC. treatment is important storage capacity. 3.1.7. Post-Synthesis Treatment Post-Synthesis Treatment 3.1.7. nanostructure in tuning the CDC important parameter Another treatment a post-synthesis annealing. Usually, is post-synthesis at a tem- after chlorination, is carried out like hydrogenation than the CDC synthesis temperature, perature equal to or lower or chlorine containing compounds. to remove residual chlorine to 40 wt% residual chlorine was captured Considering that up in the pores after Ti fl in the carbon structure, where an initially disordered CDC in the carbon structure, where an initially annealing while structure is largely maintained during argon be observed after NH a higher degree of structural order can pore coarsening. 3.2. Hydrothermal Treatment 3.2.1. Basics of the Hydrothermal Decomposition of Carbides Hydrothermal treatment is another way for reactive chemical removal of metal or metalloid atom(s) from the carbide network formation by hydrothermal treatment to produce CDC. Carbon was fi fi (Tyranno) note that the resulting properties such as excess uptake of gas note that the resulting properties such as procedures. for gas storage may be affected by post-treatment H or water vapor etching or H was observed (0.8 nm compared to 0.6-0.7 nm for pure TiC). a water/argon mixture annealing at 900 Similarly, annealing conditions in such a way that benefi annealing conditions not compromised. Compared to treat- like the high SSA are or hydrogen, argon annealing shows lim- ment with ammonia removal. ited potential in chlorine concentration treatment yielded the lowest residual chlorine below 1000 especially for CDC obtained at temperatures was corroborated in The high reactivity of CDC with ammonia et al. a recent study by Adu for chlorination instead of pure TiC. opens up clogged pores and results in larger measured spe- opens up clogged pores cifi

] ] ] 2

96 92 93 ] , [ [ u- 89 92 [ , C. cant This ] ° 90 , 95 and I [ 2 48 , or highly ] 46 , 4 [ , Br 34 , 2 24 For SiC chlo- SiC For [ ] and onion-like ] 94 [ -Ar at 1000 2 94 [ 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim GmbH & Co. 2011 WILEY-VCH Verlag C. ° : 96.1% Ar mixture : 96.1% Ar mixture © 2 may play a signiﬁ ] 97 , (2:1) mixtures consisted (2:1) mixtures consisted bond angles in CDC. 46 ° [ 2 :H 2 : 1.3% H 2 While similar SSA values were ] and 0%–2% H 2 28 In the absence of hydrogen, dia- [ ] 92 [ The presence of boron and other addi- The presence of boron ] 70 [ the hydrogen in the gas mixture favored in the gas mixture the hydrogen ] , 810–833 rst observations of nanotubes. CNTs were CNTs rst observations of nanotubes. 70 [

had the highest sorption capacity for iodine ] 21 C, both amorphous CDC C, 2 , C, ° 98 ° [ C. carbon. 2011 3 2

When a 2.6% Cl When a 2.6% or Br ] However, the exact mechanism of diamond forma- However, ] 2 90 [ 18 [ were reported in the literature. ] 48 [ lms. bonded carbon with a pycnometric density close to that of bonded carbon with a pycnometric bonding by stabilizing dangling bonds formed after the bonds formed after by stabilizing dangling bonding Carbon nanotubes were observed in SiC-CDC in 1972. nanotubes were observed in SiC-CDC Carbon Nanodiamond formation can also be observed for atmos- Nanodiamond formation While chlorination temperature and choice of initial carbide While chlorination temperature and choice of initial carbide 3 3 pheres without hydrogen. Till now, the mechanisms governing the growth of various the mechanisms governing now, Till nanostructures during chlorination of carbides are not yet fully understood. It is clear that the catalytic effect of impurities, additives or the metal of the carbide was studied by Babkin et al. may be one of the fi SiC also later reported for CDC obtained from ence of the choice of halogen on the resulting carbon material. CDC obtained from ZrC halogenation in Cl mond nanocrystals readily transform to graphitic carbon in the mond nanocrystals readily transform to graphitic as ribbons or onion- form of curved graphitic structures such low temperatures and limited carbon mobility, like carbon. At favored and was nanodiamond formation may be kinetically and ZrC. TiC, SiC, observed for various carbides such as CDC coatings obtained from Cl CDC coatings obtained at moderate Annealing of amorphous CDC after synthesis of presumably temperatures may also lead to the formation sp role in nanostructure formation although the low-temperature limit for CDC synthesis and the properties of low-temperature CDC are yet to be determined. are the dominant factors in determining CDC porosity and microstructure, there are also reports on the structural infl was used at 950 was used rinated at 1000 disordered sp or bromine respectively. This was explained in terms of sur- or bromine respectively. face termination and possible effects of the size of the halogen and produced zirconium halogenide molecules. It is important to note that not only porous disordered carbon, but also well- ordered graphite and graphene can be produced by the chlorination of Fe reported for the three different halogens, it was found that ZrC treated by I diamond. of a loosely attached, powdery top carbon layer with a dense, powdery top carbon layer with a dense, of a loosely attached, amorphous or nanocrystalline layer highly disordered, adherent, a layers were shown to be composed of below it. The adherent and diamond-structured carbon mixture of graphitic studies showed a very high elastic modulus (up to 600 GPa) to 600 GPa) modulus (up a very high elastic studies showed from diamond- as expected (up to 50 GPa), and high hardness like fi selective halogen removal of silicon from cubic SiC crystals. of silicon from cubic SiC selective halogen removal interface growth at the SiC-CDC Local epitaxial nanodiamond Cl was reported for 1%–3.5% carbon tion is still unknown and the question remains as to whether tion is still unknown and the question remains main component of nanodiamond can be synthesized as the carbon have been CDC. The carbon onions in carbide-derived at 900 reported after chlorination of TiC tives in sintered SiC ceramics may favor diamond formation. ceramics may favor diamond tives in sintered SiC if sp-bonded carbon can be produced from It is still not known suggests the chlorination of carbide precursors, but modeling presence of some percentage of 180 sp www.MaterialsViews.com Adv. Funct. Mater. Funct. Adv. FEATURE ARTICLE 820 SiO potent solvent,especiallyforsilica.Dataonthesolubilityof and fromkineticconsiderations,supercriticalwatercanbea phase indicatestheformationofbothcarbonandmetaloxide, CH 285 H namic analysisindicatedthatcarbon,MO M perature (300–1000 energy minimizationalgorithms.Jacobson studiedawidetem- under hydrothermalconditionswerecarriedoutusingGibbs At lowH different stoichiometry-governedregimeswereidentifi formation issensitivetothewater-to-carbide ratio,andthree product. hydroxides thataremixedwithcarboninthefi high dissolutionrates,butrathertheformationofoxidesand can beexpectedindistilledwater in theamountofcarbonproduced. H remains theonlystablesolidreactionproduct.Finally, athigher formed silicaisimmediatelydissolvedintothefl are formedbutthelargesurplusofwaterensuresthatany conditions. ever, waspredictednottoyieldany carbonunderhydrothermal in hydrothermalfl although wemustaccountforalowermetaloxidesolubility and NbCshouldshowabehaviorverysimilartothatofSiC lower carbonyield.From calculations,weexpectthatTaC, TiC, the otherhand,increasestabilityofmethaneleadingto a the yieldofCH tion ofthecarbideprecursor. Asatemperature-sensitivefactor, containing gasspeciesformedduringhydrothermaldecomposi- active oxidationofsiliconcarbideisobserved. MO MC MC MC x written asfollows: perature rangeofthestudy, andtheprincipalreactionswere the surface.At intermediateH μ temperature to500 year attemperaturesbelow100 and pHconditions,valuesareaslowseveralnmper wileyonlinelibrary.com www.afm-journal.de / m s m 2 2 2 x MC Thermodynamically speaking,theformationofanoxide Thermodynamic calculationsforanumberofmetalcarbides Experimental studiesonSiC clearlydemonstratedthatcarbon A criticalfactorforthecarbonyieldisamountofcarbon- O:SiC ratios, neithercarbonnorsilicaisformedandonly arethemainproductsofhydrothermalreactionsintem- C–H

4 2 x + + ° isunstableathightemperatures,resultinginanincrease + stronglydependsonthechosenpressure,temperature C and100MPa, asilicasolubilityrateof2.5 · 10 + − ( ( 1 x + x x . n 2 H [ 112 O withM + + x H 2 2 H O:SiC ratios,bothcarbonandsilicaaredepositedon 2)H 1)H 2 O [ ] 113 For othermetaloxides,wedonotexpectsuch O 2 O → ] → 2 2

O O → MO 4 MO → → decreaseswithincreasingtemperatureas uids formostoxides.Boroncarbide,how- M = x Si, Ti, Ta, Nb,WorB. x ° MO MO x ° C) andpressurerange(2–200MPa) for / + 2 C, solubilityrateincreasestoseveral · O C n x x x H + + + + 2 x x O CO CO H / 2CH 2 2 O:SiC ratios,carbonandsilica 2 + + ( ° (8) [ x 4 C andatapHof7. 111 ( (9) x [ + 113 (5) + ] 1)H andbyincreasingthe ] 2)H Higher pressures,on x , CH ,

2 © [ 2 110 (6) 2011WILEY-VCHVerlag GmbH&Co. KGaA,Weinheim (7) ] 4 Thethermody- uid andcarbon , CO , nal reaction nal 2 ed. , CO,and − 8

μ [ 113,114 [ m s m 71 ] At − 1 ]

at 400–700 case ofchlorination. provided noprotectionagainstfurtherreaction,exactlyasinthe at highertemperatures( metal oxidespecies.InthecaseofTi the formationandpossibledissolutionkineticsofatleasttwo I 100–170 MPa. treatment forWC,TaC, NbC,andTiC at500–750 Experimental dataconfi ronment alone,Cr either glassycarbonornanospheres. sucrose, SiC wasreportedtodecompose,producingsilicaand 400 ment wasreportedonthesurfaceofTyranno fi exceeds thatofmostmetals. of thecarbide-formingelements,asmeltingpointcarbon carbon duetoincongruentmeltingofcarbideandevaporation inert atmospheresisanotherroutetotransformcarbidesinto Thermal decompositioninavacuumorhigh-temperature 3.3.1. General AspectsofThermalDecomposition 3.3. ThermalDecompositionofCarbides found onthesurfaceof structured carbon,graphite,andamorphouscarbonwere β on Tyranno fi Raman spectraofCDCproducedbyhydrothermaltreatment 3.2.2. Carbon Structure graphitic carbon. band (D),confi domain sizecanbefound,asindicatedbyanincreasedI Raman datasuggeststhatathighertemperaturesasmaller was confi tals aftertreatmentat300–800 carbide (Cr materials inthehydrothermaldecompositionofchromium fi and 700 treatment at35MPa fortemperaturesrangingbetween500 with highlydisorderedcarbonwasreportedafterhydrothermal whiskers, andpowdersat600–800 also demonstratedforAl sition tosynthesizehigh-purity epitaxialgraphiticcarbonwas are commerciallyavailable.Thepotentialofvacuumdecompo- but iscurrentlytheonlycarbideforwhichlargesinglecrystals because siliconcarbideisnotonlythemostcommon ious forms(powder, fi trated onthethermaldecompositionofsiliconcarbideinvar- nanotubes. ethylene yieldsvariouscarbonnanostructures,suchas hydrothermal decompositionoforganiccompoundslikepoly- peratures ( lamentous carbonwerealsoreportedfor these acidicorganic G -SiC) showedabandofgraphite(G)anddisorder-induced ratio. In thepresenceoforganicacidssuchasmalonic acidsor Formation ofamorphouscarbonafterhydrothermaltreat- ° C and100MPa [ 122 rmed viaX-ray photoelectronspectroscopy(XPS),and ° C. ]

< [ 125 3 [ 30 300 ° 122 C C and200MPa, bers (amorphousSiO ] 2

[ rming theformationofamorphous/disordered ] 120 ). Thepresenceofsp [ ° 124 [ 115 ] C) oronlytheformationofchromiumoxide With ternarycarbides,onemustconsider 3 ] Whenexposedtoahydrothermalenvi- ] C [ However, thecarbonﬁ 116 2 bers, singlecrystals,wafersetc.)mainly showedeitherno reactionatlowtem- [ rms carbonformationviahydrothermal ] 107,108

4 α > C 30 350 - and 3 byFoster etal. ] CVD-SiC ﬁ [ [ 117 126 ° C). β ] ] ° Moststudieshaveconcen- and -SiC powderandsinglecrys- C and100–500MPa. [ 2 124 Adv. Funct. ad sp and 3 x SiC C

] Itshouldbenotedthat ° y α

withnanometer-sized C. 2 - and bers aftertreatment www.MaterialsViews.com , rutile/anatasealong [ 110 [ lm wasporousand 127 3

Mater. hybridizedcarbon [ , 123 118,119 ]

β ] Sphericaland

-i platelets, -SiC 2011 bers at300– ] Diamond- , 21 ° , 810–833 C and C [ 120,121 D / ]

FEATURE ARTICLE 821

] ] 146 144 [ [ lm -SiC -SiC The bers ] a). β Carbon lms. ] ve times However, were per- ] 139 142–145 ] [ , 30 11 [ 11 [ [ Figure 8 Figure -SiC -SiC whiskers C. β ° wileyonlinelibrary.com www.afm-journal.de lms.

] observed a minor observed a minor ] 2 [ A typical CNT ﬁ reported that ] ] 134 [ 11 [ 147 [

] for the C-face. 2 140 − [ while other methods, such as ] showed that scratches on the One important feature of CNT ] ] 6 6 [ [ a. reported enhanced carbon forma- reported enhanced ] 142,143 6 [ [ Torr) at 1700–2000 at 1700–2000 Torr) 5 − -SiC single crystal were observed after heat -SiC β and Shimizu et al. ] lms are reported to consist of carbon nano- 11 Torr using in situ laser heating in a TEM. Torr [ 9 − -SiC single crystals that were rapidly heated to single crystals that were rapidly -SiC β were transformed into freestanding CNT lms on Si

] for the Si-face and 0.3 J m for the Si-face In similarity with the shape conservation of SiC fi with the shape conservation of SiC In similarity 141 ] [ 2 − uence of the protective oxide layer on silicon carbide, uence of the protective oxide layer C at 10 136 ° [ /Si /Si substrate. 2 Surface inhomogeneities such as scratches also play a vital as scratches also play such inhomogeneities Surface First experiments reported by Kusunoki et al. experiments reported by Kusunoki First lms by SiC decomposition and subsequent removal of the lms by SiC laser evaporation or CVD, usually result in zigzag, armchair, laser evaporation or CVD, usually result in zigzag, armchair, and chiral tubes coexisting in the products. grown via SiC decomposition is that no metal catalyst is involved grown via SiC in any step of nucleation or growth of the fi annealed in vacuum (10 polishing were still visible on surface remaining after SiC demonstrating the CDC surface after vacuum decomposition, ( the shape conservation during carbon formation 3.3.3. Carbon Nanotubes Produced by SiC Decomposition Nanotubes Produced by SiC Decomposition 3.3.3. Carbon demonstrated that vacuum decomposi- et al. In 1997, Kusunoki tion of silicon carbide can be used to epitaxially produce self- organized carpets of carbon nanotubes. 2.2 J m 3.3.2. Conservation of Shape 3.3.2. Conservation of In 1962, Badami pointed out that vacuum decomposition shape so that even nano- conserves the original carbide SiC visible in the resulting scopic features such as growth steps are CDC. , 4 shown in Figure transformed into CDC by chlorination of we observed a conservation of the shape treatment. Similar results were obtained from heating SiC in in results were obtained from heating SiC treatment. Similar a vacuum furnace, giving rise to continuous CNT fi growth on the C-face was reported to be as much as fi to be as much as the C-face was reported growth on on the opposing Si-face. faster than on the carbide surface as defects and tion around scratches Impuri- bonds accelerate thermal decomposition. strained Si-C were also reported to give rise to the for- ties, such as sodium, graphitic carbon on the surface of silicon mation of non-planar Both scratches and impurities weaken carbide single crystals. the infl from vacuum decomposition. The which shields the substrate with thicker scales on the Si-face layer, role of the initial oxide the C-face, should always be taken into and thinner layers on account. role in what and where carbon nanostructures of different types nanostructures of different and where carbon role in what et al. are formed. Cambaz resulting CNT fi tubes of the same chirality on SiC is shown in Figure 8 Figure is shown in on SiC formed on 1700 Overlapped CNTs with caps of 2–5 nm oriented along the [111] Overlapped CNTs direction on (111)- et al. Kusunoki (111) CVD fi fi SiO loss of the original particle shape after electron-beam assisted loss of the original particle shape after electron-beam interface was while the SiC-C vacuum decomposition of SiC et al. still topotaxial. Cambaz some sharp edges were smoothened after vacuum decompo- some sharp edges were smoothened after of the higher carbon sition at higher temperatures as a result mobility and graphite formation. Iijima Torr, C are -axis). 5 ° c Struc- − ] 136 [ ed with an C at 10 ° For short diffu- short For ] 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim GmbH & Co. 2011 WILEY-VCH Verlag 47 [ © -SiC whiskers ther- -SiC but it may depend on β Torr yielded graphite yielded graphite Torr ] 6 Electron beam induced Electron beam surface reconstruction ] − ] 137 [ 133 138 [ [ lm forms, a gradient in the Si in the Si lm forms, a gradient

] C and 10 ° Structural reorganization especially ] 128,129 [ Early experiments by Badami showed Early experiments by Badami ected in almost all physical and chem- ected in almost all 137 ] [

] 132 , 810–833 [

] 21 135 C. [ , This was attributed to the size effect and ° ] where dense graphitic carbon was found after where dense graphitic carbon was 135 ] [ 135 ected by the large difference in surface energy of [ 2011

-axis to the SiC substrate were identifi -axis to the SiC C marks the lower temperature limit for carbon c is beyond the scope of this paper. It is, however, It is, however, is beyond the scope of this paper. ] Interestingly, studies on Interestingly, ° 130,131 ] [ 138 , 134 [ 71 [ Similarly to the discussion in Section 2.1.3, one should con- 2.1.3, one should discussion in Section to the Similarly With silicon carbide itself being extremely complex with silicon carbide itself being With A critical aspect to carbon formation from SiC was addressed formation from SiC A critical aspect to carbon First studies of SiC decomposition were carried out in the decomposition studies of SiC First formation via thermal decomposition, carbon formation on 6H-SiC also strongly indicated topotaxial also carbon formation on 6H-SiC basal plane of silicon CDC with graphite layers parallel to the carbide. applies to the complexity of initial carbon formation and its applies to the complexity of initial carbon formation and its interplay with surface reconstruction of silicon carbide. Pres- 800 ently, that heating 6H-SiC single crystals to 2050–2150 single crystals that heating 6H-SiC of SiC of SiC heating to 2000 sider that once formed, silicon must be transported outward must be transported once formed, silicon sider that carbon layer. inward growing through the mally decomposed at 2400 lack of exposed basal planes. Additionally, it was observed that lack of exposed basal planes. Additionally, were tangent to the the basal planes of the graphite domains whisker surface. tural reorganization is, therefore, a key parameter of carbide tural reorganization is, therefore, a key decomposition and it is facilitated by higher carbon mobility at elevated temperatures. polytype when discussing the essential to consider the SiC initial stages of carbon formation and especially the forming of single-layer graphene, where the interaction between the layer is important. Another carbon layer and the underlying SiC is the well-known key aspect of carbon formation from SiC anisotropy which is refl ical properties of silicon carbide. As a result; we see different carbon nanostructures and growth rates for the different SiC surfaces as refl more than 280 different polytypes, by Badami: the number of carbon atoms in a layer of SiC is in a layer of SiC by Badami: the number of carbon atoms In graphite layer. smaller than required for forming a dense bilayers. fact, one graphene layer consumes 2–3 SiC nanocrystallites with no epitaxial relation to the carbide pre- nanocrystallites with no epitaxial relation cursor lattice. yields turbostratic carbon and graphitic carbon that exhibits yields turbostratic carbon and graphitic lattice. In SiC epitaxial features with respect to the underlying ordered either par- fact, it was observed that carbon layers are stacking direction (i.e., allel or perpendicular to the SiC Within the turbostratic carbon matrix, graphite crystals with the turbostratic carbon matrix, graphite Within a common and the graphite outer layer dominated by turbostratic carbon interface. domains close to the SiC-C typically reported. SiC surface conditions as temperatures higher than 1100 SiC sion path lengths, we observe effectively linear decomposition effectively linear decomposition lengths, we observe sion path fi the porous carbon kinetics. As up within that layer through which all fur- vapor pressure builds vapor must diffuse through. Once Si ther decomposed silicon the it effuses away from the carbon layer, reaches the surface of since effusion is faster than the material into the environment transport is presumably through carbon. Si diffusion of Si step. There is indirect evidence of silicon the rate controlling in the silicon carbide decomposition surface migration during et al. studies by Voronin late 1940s www.MaterialsViews.com Adv. Funct. Mater. Funct. Adv. FEATURE ARTICLE 822 Figure 8. in lowvacuum(b),respectively. is capableoftriggeringorsurpressingCNTgrowth,thusenablingsurfacepatterning.Reproducedwithpermission. polishing arestillevidentanddenseCNTbrushesasobtained.OutwardgrowthofisfacilitatedbytheBouduardreaction.S was observed. stage attemperaturesabove1500 then transformsepitaxiallyintographenesheets.Inafi that amorphouscarbonisformedattheinitialstagewhich While CNTgrowthwasobserved undervariousexperimental fi individual nanotubesnormaltothesurface. showed predominantlycurvedandplanargraphitewallswith nanotubes) forSiC nanopowders. Kusunoki etal nanotubes) forSiC powder of obtainedtubesrangesfromMWCNT(multi-wallcarbon position conditions(vacuum,temperature).Thespectrum quality (defects,impurities),crystalmorphologyandthedecom- crystallographic orientationofthefreeSiC surface,surface C-face of6H-SiC vacuumdecomposed at10 SiC wafers seems tobearound1900 Temperatures near1300 the SiC crystallattice,andnoCNTs areobservedinthisregime. silicon carbidesurfacesbyoxidativeextractionoffrom below 1000 as thedrivingforceofCNTformation.At temperaturesator observed at3 situ studyandanonsetofnanocapformation1360 and/or higherdecompositiontemperatures. which continuedtogrowascarbonnanotubesforlongertimes the carbonfi through theformedcarbonfi mation duetoemergingSiO gasthatcannolongerdiffuse wileyonlinelibrary.com www.afm-journal.de ed whencomparingthe Si- andtheC-faceof6H-SiC. Signifi A modelforCNTformationfromSiC wasproposedby Critical factorstoconsiderwhenformingCNTfi Carbon nanocapformationwasobserved for3C-SiC inan cant differencesinthecarbonstructureswereidenti- SEM imagesofdifferentcarbonnanostructuresobtainedfromvacuumdecomposition6H-SiCfortheC-faceinhigh(a)an [ 11 lm. Asaresult,socalledcarbonnanocapsformed , ° 142–146 C, graphitesheetsareformedonfree-standing [ × 144 [ 8 10 , 11 ] Ahighertemperaturelimit forCNTgrowth , 142–145 − ] anddefect-richSWCNT(single-wallcarbon 7 Torr. ] Themodelsuggestsresidualoxygen [ ° ° 150

[6] C. AsfoundbyCambaz etal., C areaccompaniedbybubblefor- [ TheSEMimageshowsanexampleofthecarbonﬁlm withconformaltransitionwheretheinitialscratchesfromsample 148 ]

lm fastenoughtoavoiduplifting Inthesamestudy, itwasshown ] todouble/triplewallCNTfor [ 149 ° ] C, enhancedCNTgrowth

and persistenceof the resultoftwoopposingforcesC–C show thatnanocapformationontheC-facecanbeexplainedas Kusunoki. for lowertemperaturesstartingaround1250–1300 to thesurfacealonewerefoundonSi-face. conditions ontheC-face,mainlyfl from thesurfacebeforecarbonnanotubescanbeformed. Si–O bondsneedtobebrokenandoxygenneedsremoved An initialoxidelayeronanySiC surfacepreventsCNTgrowthas C-face. layers, highertemperaturesshowCNTformationonthe bide surfaceandunsaturatedsp CNTs, asaconsequenceof90 an explanationforthezigzag-likechiralityofC-facegrown planar graphiticsheets. the evaporatingSi-layer whichcontinuestogrowasastackof face leadstothegrowthofafl which latergrowtobecomeCNTs. RemovalofSi fromtheSi- in repulsionbetweencarbonatomsatthecenterofnanocaps pendent ofSiO-related formationmechanisms.Thisresults cussed asthereasonforSi-face CNTgrowthbyWang etal. effect ofHFetchingleadingtosurfacereconstructionwasdis- length andlargerindiameterthantheCNTonC-face.The the Si-face afterHFetching.TheseCNTwerelessthanhalfthe since additionalcarbonissupplied throughthegasphase. carbon) arelongerandprotrude fromthesource(Figure 8 b), Therefore, tubesgrowninpresenceofCO(CO port playsanimportantroleinCNTformationandgrowth. the C-facebyadditionofCO CNT formationontheSi-face and enhanceCNTgrowthon Recent quantumchemicalmoleculardynamicssimulations Nagano etal. While lowertemperatures( [ 144 ] ItshouldbenotedthatCNTfi [ 144 ] Itwasalsoshownthatitispossible toobtainboth [ 151 ] observedCNTs growingperpendicularto π conjugatedgraphenesheets [ 152 ] Thesesimulationsalsoprovided 2 . < [ 6 ] 10 1500 ° 3 at graphenelayerunderneath This illustratesthatgastrans- bonds. anglebetweenthesiliconcar- [6] Copyright 2008,Elsevier. Adv. Funct. at graphitesheetsparallel ° C) yieldgraphiticcarbon [ 140 www.MaterialsViews.com ]

lms werereported

urface modiﬁcation (c) Mater. σ -od formation -bond 2

reactionwith 2011 [ 140 , , 21 152 , 810–833 d Si-face ] ° [ inde- 151 C by C [ ] 152

]

] 155 g tunnel microscopy shows [ Reproduced with permission. C were reported to show high elasticC were reported to show ] ° 157 [ ). The latter is a direct consequence of the The latter is a direct consequence of ] n 158 [ From the HR-TEM image (d) we can see that the bonding From ] 156 [ Schematic illustration of graphene growth on the Si-face of 6H-SiC Schematic illustration of graphene growth terrace step (110 ] ° CNT layers as obtained from thermal decomposition ofobtained from thermal decomposition CNT layers as 144 [ 6H-SiC wafers at 1700 wafers 6H-SiC resist- viscoelastic behavior and a very high modulus (17–20 GPa) ance to buckling. seen that, along a step, the graphite basal planes remain per- basal planes along a step, the graphite seen that, instead surface topotaxially to the original carbide pendicular shows (0002) left of the step now The lower part of epitaxially. Amorphous to (0001)-6H-SiC. is oriented parallel graphite that C-faces and (Si- surfaces SiC on amorphized carbon forms carbon/CNT. alike) instead of graphitic high packing density of vertically standing MWCNTs (2–4 walls) of vertically standing MWCNTs high packing density der viscoelastic behavior due to Van giving raise to pronounced It has been ] Copyright 2010, Materials Research Society. Reproduced with permission. 2010, Materials Research Society. Copyright 3 a), it can be a), it can ] [ 156 [ 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim GmbH & Co. 2011 WILEY-VCH Verlag © Figure 9 Figure cation, both CNT and graphite cation, does not explain the differences in the differences in does not explain ] 144

[ ] 6 [ While most graphite (0002) planes are While most ] , 810–833 144 [ 21 , and different growth kinetics. and different growth kinetics. ] A different number of graphene layers (e) can be seen on a 30 ] 7 [ 2011

153,154 uence of surface morphology on topotaxial carbon formation (a). [ I n fl Similarly, different carbon nanostructures were observed on carbon nanostructures were observed on different Similarly, The Kusunoki model The Kusunoki gurations perpendicular towards (0001)-6H-SiC ( (0001)-6H-SiC perpendicular towards C- and Si-face but only the transition from graphite to CNT. graphite to CNT. the transition from but only C- and Si-face the thickness anisotropy mainly consider for SiC Explanations of the layer and the quality of the initial oxide and composition con- consider different bonding but do not polished surface, fi the C-face of SiC. the C-face of SiC. shown that, by surface modifi shown that, by surface enabling surface of SiC C- and Si-faces can be grown on both c). 8 patterning (Figure distance between the fi rst graphene layer and the topmost SiC layer is signifi smaller than the graphene–graphene spacing cantly rst graphene layer and the topmost SiC layer is signifi distance between the fi bilayer distance. Figure 9 . Elsevier. Elsevier. 1999, Taylor & Francis. Reproduced with permission. & Francis. 1999, Taylor (b, Ref. [ 156 ] ). After forming a buffer layer (layer 0) graphene layers emerge with characteristic nanostructure. Scannin ). After forming a buffer layer (layer 0) graphene layers emerge with characteristic nanostructure. ] 156 [ (b, Ref. the characteristic, well-ordered honeycomb arrangement of carbon atoms in layer 2 (c). www.MaterialsViews.com Adv. Funct. Mater. Funct. Adv. FEATURE ARTICLE 824 plane depictedinFigure 9 e. also showadifferentnumberofgraphenelayersasinthebasal pressures pheres atambientpressure,orextremelylowoxygenpartial vacuum conditions(e.g.,10 bubble formation,grapheneformationfromSiC requiresstable a thingraphenelayerformspriortoCNTuplift.To avoidany in 1987. or thingraphitelayerbeforethetermgraphenewasintroduced band gap. and closeinteractionswiththeSiC substrateasshownbya with acarbondensityclosetothatofmonolayergraphene torts theuniformityofgraphenelayer. It mustbeconsideredasadetrimentaleffectitlocallydis- and isassociatedwithpointdefectsratherthandislocations. at (110 of (0001)vs.(110 Step erosionwaslinkedtothedifferencesinsurfaceenergy terrace stepscanrecedetogiveriseonegraphenelayer. preferential decompositiononedges.Hupalo reportedthatthree characterized bystepbunchingoftwoSiC bilayersasaresultof The initialstageofgraphenelayerformationatterracestepsis or heatingininertgasatmospheres. onstrated theirpotentialaselectricalbrushcontacts. CNT fi for applicationswheremechanicalenergymustbeabsorbed. Waals interactionsbetweenthetubes.TheseCNTs couldbeused R30 For theSi-face, SiC fi aspects ofgraphenegrowth(Figure 9 ) aswelltopotaxialeffects. during SiC decompositionattemperaturesbelow1200 at hightemperatures.Pitformationiscommonlyobserved graphene fi fi graphene onSiC isapromisingwaytoobtainhomogenous Bommel in1975, Graphene istheproductofSiC vacuumdecomposition 3.3.4. GrapheneFormation bySiCDecomposition and mayprovidenewinsightsintotheCNTgrowthmechanism. studies ofCNTgrowthoncarbidesotherthanSiC aremissing extraction ofsiliconfromtheSiC precursor. Also,systematic as theSiC decompositionprogresses. graphene layers,likelayer2in Figure 9 d, will thenbeformed graphene-graphene interlayerdistance( much closertotheSiC surface(2.9 Å)incomparisontothe scopy (STM)imagespresentedinFigure 9 c. Also,layer0 is found inlayer1.Thisisseenfromthescanningtunnelmicro- known honeycomb-likestructureandelectricconductivity strate bysaturatingdanglingbonds,givingrisetothewell- layer. Thebufferlayerprovidessomeisolationfromthe sub- start attheterracestepsthatequal(110 be foundinReferences165and166.Nucleation wasreportedto play animportantroleingraphenegrowth. is notperfectlyfl wileyonlinelibrary.com www.afm-journal.de lms onalargescale. From astructural pointofview, oneshouldconsiderepitaxial However, itisstillunclearhowtogrowSWCNTarraysvia A detaileddescriptionofthegrapheneformationmodelcan ° socalled“buffer” layer (layer0inFigure 9 ) lms obtainedfromcatalyticsynthesishavealreadydem- n [ ) SiC. ) 163 [ [ 5 174 , lms form,promotedbyenhancedcarbonmobility 8 ] From theCNTgrowthmodel,itisassumedthat , 162 ] Layer1willthenbeformedontop ofthebuffer [ 8 ] With thelimitationsofexfoliation,epitaxial , 166,167 at butcharacterized bystepsandterracesthat n [ ) SiC andthehighnumberofdangling bonds 160 ] rst reconstructs rst itwasreferredtoasamonocrystalline ] Assteperosioncontinues,continuous [ 156 , 165 [ ] 157 Onanatomiclevel,however, SiC − 5 –10 ]

− 10 Torr, [ 156 [ 8 ] , toforma 162 ∼ [ 157 3.5 Å).Subsequent ] © Describedbyvan n [ , 2011WILEY-VCHVerlag GmbH&Co. KGaA,Weinheim 156 164 ) faceofSiC. , ] 170,171 ), inertatmos- [ ( 159 6 √ ] Terraces ]

36 ° × [ [ 160,161 172,173 C C [ 7 √ [ [ [ [ , 170 169 168 166 157 3) ] ] ] ] ] ] ]

rotational carbondomains. distorted bynanocaps,theonsetofnanotubeformation,or able annealingconditions. imize excesscarbonformationduringheatingandchoosesuit- one shouldadjusttheheatingrateortime/temperaturetomin- or removaloftoxinsandcytokines fromhumanblood. the that reducingtheoff-axis deviationforthe(0001)planefrom to Si-deposited SiC surfaces decomposition, condtionsvaryfromnosamplepolishing, carbide. rination ofFe from. Formation ofwell-orderedgraphite/graphenebychlo- formation anditsrelationtothecarbidesubstrateitoriginates is necessarytoimproveourbasicunderstandingofgraphene icon carbide,hasnotbeenstudiedindetailyet.Work inthisarea at temperaturesbelowthegraphenegrowthonsetlevelforsil- Graphene growthfromothercarbideprecursors,possiblyeven tration ofepitaxialgraphenecanbecontrolledbythesubstrate. gated anditwasshownthatthechargecarriertypeconcen- of layersisusuallyusedforgraphenegrowth. slower growthrateandallowsabettercontroloverthenumber route toremovesurfacedefects. ment. several reportsondifferentproceduresforSiC surfacetreat- mechanical polishing(CMP)maynotbesuffi possible toacertaindegreebutitisclearthatregularchemical atomically fl layers. Optimalgraphenegrowthwillonlybeobservedfor considered whenlookingattheformationofgraphenesingle 1500 is apowerfulselectivesorbentforvariousmolecules there arenumerouspotentialapplications.CDC,inparticular, Given thevarietyofCDCnanostructures,itisobviousthat 4. ExamplesofApplications CDC multilayers showadecayofperformance, suitable forapplicationssuchas purifi carbon layersarealsolikelytoshowwrinkles. circa 10layers,asknownfromabinitiocalculations. approaching thepropertiesofbulkgraphiteatathreshold electron mobility, withanincreasingnumberoflayers, by Yang etal., equal totheunitcelllengthof6H-SiC. growth oncarbidesmaybeachievedinvariousenvironments. and semi-insulatingsiliconcarbide. atomically fl 10–15 Å,thereseemtobefundamentallimitationsobtain of thecarbidesurface.Belowthatthresholdapproximately 10–15 Å)arearesultofbettercontrolthecrystalorientation step height,improvedcharacteristics(width:6 the polishedSiC. Insteadofa2 The C-faceofSiC showsgraphenethatis,however, often In reportedstudiesongrapheneformationfromSiC vacuum Also, substrateorientationisimportant;itwasreported Control ofgraphenegrowthisimportantbecause Graphene formationwas describedfordoped(n-andp-type) c -axis from0.25 ° [ 180–185 C yieldedstepheightsofapproximately15Å, [ 164 , 173 at surfaces. at anddefectfreesurfaces.Thelattermayonlybe ] EtchingSiC waferspriortosynthesisisapossible ] 3 ThetopmostlayerofSiC mustbecritically [ 189 C hasbeenshown, ] differentnitrogendopinglevelswereinvesti- ° to0.03 [ 140 [ 178,179 ° signifi ] Therefore,theSi-face thathasa μ ] m terrace widthand40–50Å andhydrogenetchedsilicon [ [ 169 98 Adv. Funct. cantly reducesterraceson ] [ suggestingthatgraphene , 6 184 cationofnoblegases , 174 [ 186 ] Hydrogenetchingat , 188 ] www.MaterialsViews.com

[ 175

] Mater. Inarecentstudy ] suchasreduced cient. Thereare [ 6 , 168

2011 [ μ , [ 157 177 184 m height: m; , [ ] ] 176 ] 21 Thicker

[ whichis 3 ] , 810–833 andis [ ] 55 Thus, ] The [ [ [ 187 166 190

] ] ]

FEATURE ARTICLE 825 - 4 for ] TEA- 200 c sur- [ M Lower A sim- lms. A ] ] 41 [ TEA-BF 205 [ cant inter- cant M ). for 1 1 − Traditionally, a Traditionally, ] , and compared , and compared wileyonlinelibrary.com The importance The importance

] www.afm-journal.de ] 202 [ 204 210 [ uorethylene (PTFE) [ Figure 10 Figure Studies performed on Studies performed ] capacitance, as reported 3 203 [ lms in 1.5 This enables the direct This enables the direct

] Figure 11 Figure cult to achieve using other have shown that for small An example of a TiC-CDC An example of a TiC-CDC C, and with pores of an C, and with pores

63 ] ] [ ° m due to limitations in ion m due to limitations in ion 63 , 202 μ [ for TiC-CDC was reported in was reported in for TiC-CDC The use of materials without The use of materials A high total surface area, pore A high total surface 3 41 ] ] [ lm in the same way as acti- were found in organic electro- lled with electrolyte that cannot electrolyte that cannot lled with 3 81 − [ in aqueous electrolyte. 3 − 206,207 , acetonitrile solution, where VC-CDC acetonitrile 4 m thick thin fi 200 , μ lms can be created on a large number lms can be created on a large number 84 , 30 F cm NBF uoride (PVDF) and then formed into a uoride 3 56 ∼ , As illustrated in 53 ] , but only up to 39 F/cm but only up to 39 F/cm ] CH lms of over 100 41 50 3 [ cantly increased for monolithic CDC fi [ ) CDC fi 5 ]

41 H [ 208,209 2 [

lm with enhanced volumetric capacitance is shown in lm with enhanced volumetric capacitance is shown in solution in acetonitrile. solution in acetonitrile. 4 Templated mesoporous carbon is another material exhibiting Templated Different approaches for the manufacturing of CDC elec- Different approaches for the manufacturing of CDC It should be noted that in a binder/CDC mixture or any mixture or any It should be noted that in a binder/CDC manufacturing of supercapacitors with high volumetric manufacturing of supercapacitors with high volumetric capacitance on a silicon chip. thin fi Figure 11 b. CDC with 0.7 to 1.1 nm pores CDC with 0.7 to 1.1 BF and CDC/ polymer binders may increase electrical conductivity increased mechanical pyrolytic carbon composites offered an strength, average diameter of 1.18 nm, gave the highest capacitance value average diameter of 1.18 nm, gave the highest a) 6 of CDC pore size (Figure Thus, the tunability of 133 F/g. of electrodes for a and controlled PSD allows optimization variety of electrolytes which is diffi obtained by chlorination at 900 carbons. of pore size tuning with sub-Angström accuracy was shown on sub-Angström accuracy was shown on of pore size tuning with liquid electrolyte ( an example of an ionic lyte for thick fi transport. high capacitance. Korenblit et al. showed that nanostructured high capacitance. Korenblit et al. showed silica template silicon carbide obtained from a mesoporous F g yields CDC with a capacitance of up to 170 values of below with other carbon materials, the volumetric capacitance with other carbon materials, the volumetric capacitance can be signifi maximum value of 180 F/cm of different substrate materials. an increase in the gravimetric and volumetric capacitance at and volumetric capacitance in the gravimetric an increase although the specifi temperatures, lower chlorination decreased. pore size of CDC face area and sizes tuned to the electrolyte ion size, and ensuring that all pore sizes tuned to the electrolyte ion size, and limitations is the volume is accessible to ions without transport key for achieving high capacitance. CDC powder is mixed trodes have been proposed. Usually, with a binder material such as polytetrafl or polyvinylidenefl 100–200 micrometer thick fi vated carbon. a 1 M (C be used for capacitive energy storage. Thus, monolithic microporous bodies are another approach to improve device performance. a recent study for 2 other powder-based electrode, there will be a signifi other powder-based particle macropore volume fi in aqueous electrolytes for these materials. pores, the solvation shell of the electrolyte ions is completely shell of the electrolyte ions is completely pores, the solvation leading to an increase in the capacitance. or partially removed correlation between pore size and capaci- A later study on the an increase in capacitance when the pore tance corroborated of the desolvated ion and a decrease once size approaches that than the ion size. the pore size is smaller ACN, and of 160 F cm decrease in capacitance was expected for submicrometer pores for submicrometer capacitance was expected decrease in to the electrolyte. that are inaccessible was described by Thomberg et al. ilar bell-shaped curve

] ] - 1 - 4 − 54 61 , [ In as ] ] 29 [ 50 [ . 191 [ C, 4 4 electro- 4 SO B Electrical ] ] 2 eld of per- 56 74 , [ NBF 3 54 [ Up to 180 F g Up to 180 ] CH Unlike batteries, 3 ] 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim GmbH & Co. 2011 WILEY-VCH Verlag AlC, ) 2 ected in the capaci- 200 5 © [ 192 , H 9

[ 2 ] Ti ] 198 [ 199 (C , As a more recent example, ] M 56 [ uoroborate in acetonitrile; have been studied as super- 194 ] [

] in1 1 200 [ C (75 F/g) or SiC (110–120 F/g). (110–120 F/g). or SiC C (75 F/g) 199 −

, SiC, 4 ] ] 9 [ 81 as electrodes for Li-air and Li-ion for Li-air and as electrodes , ] 9 [ 78 [ -derived carbon showed a higher gravi- 195–198 carbide- application for elds of possible , or VC, 3 c surface area. ] while VC-CDC showed a capacitance of ] 56 C , , 810–833 84 C-derived CDC also yielded a high gravi- 4 , 84 2 [ 41 [ 21 56 [ , C, on the capacitance of CDC, because cant impact 2 2011

ciency of more than 95%. ciency than CDC from B ] Mo ] in the same organic electrolyte. in the same Typical applications can be found in the fi applications Typical ] Gravimetric capacitance of 190 and 150 F/g was and 150 F/g capacitance of 190 Gravimetric 1 ] 58 202 , [ − 193 56 , 201 [ [ 9 , [ 3 C While the carbide precursor, particle size and other para- While the carbide precursor, Mesoporous Mesoporous Mo CDC with controllable nanostructure and pore character- CDC with controllable nanostructure and 4 sonal electronics, mobile telecommunications, back-up power sonal electronics, mobile telecommunications, storage and boosters for vehicles. meters affect CDC capacitance, the synthesis temperature has the most signifi of pore size in a). Tunability 6 it affects the pore size (Figure CDC facilitated a major breakthrough in understanding capacitive charge storage in porous carbon. Chmiola et al. reported Al It has also been shown that capacitance of CDC decreases with increasing particle size. capacitance in organic electrolyte has been reported for KOH et al. and explained by a signifi by Portet activated TiC-CDC cantly increased specifi ACN (tetraethylammonium-tetrafl 140 F/g) supercapacitor electrodes, supercapacitor KOH electrolyte, Al metric capacitance of 143 F g metric capacitance (260 F/g) than SiC-CDC (200 F/g) and TiC- (200 F/g) than SiC-CDC metric capacitance (260 F/g) CDC performs better in organic electrolytes such as TEA-BF where energy is stored chemically, supercapacitors or electric where energy is stored chemically, charge separation double-layer capacitors (EDLC) use physical process of charging on high surface area electrodes, making the In fact, more and discharging fast and completely reversible. expected service life- than a million recharge cycles and an for commercial time of more than 10 years have been reported after 20 years, a capacity degradation of supercapacitors. Even available supercapac- only 50% was reported for commercially itors. 133 F g removal of toxic compounds from water or capacitive water from water or capacitive toxic compounds removal of are other fi desalination applications variety of further There is a large derived carbon. cells, supports for fuel as; as catalyst for CDC such the Airbus A380 employs supercapacitors for its 16-door emer- the Airbus A380 employs supercapacitors gency door opening system. energy storage and gas storage are only two of many examples, storage are only two of many examples, energy storage and gas the most extensively studied ones. although they are currently a few selected applications are highlighted In the next sections, in more detail. Li-ion Batteries Electrode Material for Supercapacitors and 4.1. has recently attracted much atten- energy storage Capacitative energy uptake (in seconds) and delivery tion because of fast with an effi found for ZrC-CDC and TiC-CDC, respectively, in H respectively, found for ZrC-CDC and TiC-CDC, istics, obtained by chlorination of various ceramic precur- istics, obtained by chlorination of various sors such as TiC, capacitor electrode materials. Differences in total pore volume, capacitor electrode materials. Differences of CDC prepared pore size distribution and carbon structure from various carbide materials are also refl tance. lyte in acetonitrile, batteries, or for hydrogen and methane storage. batteries, or for hydrogen www.MaterialsViews.com Adv. Funct. Mater. Funct. Adv. FEATURE ARTICLE 826 permission. iue 10. Figure and 200 tion toLiC yields uniformgraphenelayers whichareconvenientfor well-controlled process.Vacuum decompositionofSiC wafers manufacturing ofdevicesforreal-worldapplicationsrequires a reported ondevicesizesupto10 lately. silicon, graphenetransistorshaveattractedmuchattention hole mobility)atroomtemperatureincomparisonwith increase intheintrinsiccarriermobility(bothelectronand Because ofextraordinary propertieslikethe100-fold 4.2. Graphene-basedElectronicDevices trode materials. from avarietyofcarbideprecursorsforlithiumbatteryelec- been seeninarecentpatentontheuseofCDCmaterials degradation. Thismaterialdegradation,forexample,has leading toslowercharge-dischargeratesandfastermaterial intercalate betweentheclosely-spacedgraphenelayers, rates incomparisontographite,whichrequiresLiions ular mayofferalongerlifecycleandfastercharge/discharge clusters. DisorderedcarbonsingeneralandCDCpartic- pore wallsandLiaccumulatesintheporesformingmetal can bebuiltusingexfoliatedgraphene. wileyonlinelibrary.com and Mo ium-ion batterieshasalsobeenexplored.WhenSiC-, TiC- diffusion data, to capacitance,werepresentalesseramount.Basedon www.afm-journal.de It wasdemonstratedthatworkinggraphenemicrodevices The useofCDCaselectrodematerialinanodeslith- [ 215–218 2 ° C-derived CDCs C LiC C, Correlation betweencapacitanceinEMI-TFSIionicliquidelectrolyte(normalizedbySSA)andTiC-CDCporesize. [ 205 6 ] .

2 CO 3 24 [ 211 andLi wereidentified viaXRDinaddi- ] werelithiatedbetween30 μ m. However, thereproducible 2 C 2 [ 219,220 , whicharedetrimental © ] Novoselovet al. 2011WILEY-VCHVerlag GmbH&Co. KGaA,Weinheim [ 219 ° C ]

rates. power micro-supercapacitors withhighcharge/discharge graphene incurrentcollectorsandtheelectrodesofhigh capacitors. from thesubstrateviasocalledScotchtapemethod. tional etching. micropatterning response time. can beusedinmicro-supercapacitors,providingaveryshort larly toCDC in aqueous(99F/g) andorganic(135F/g) electrolytes.Simi- from agglomeratedgrapheneproducedgraphiteoxide suffi observed for(110 transistors (FETs) areassociatedwithfacetingofSiC andcan be tropic transportpropertiesofepitaxialgraphenefi much smallercarrierdensitycomparedtotheC-face. was reportedtohaveahigheroff-to-on resistanceratiobuta for graphenetransistors,andontheSi-face of6H-SiC tion ofsiliconcarbide.BothSi andC-face6H-SiC werestudied made fromgrapheneepitaxiallygrownbyvacuumdecomposi- top- andside-gatedgraphenefi scattering. decrease forsupportedexfoliatedgrapheneduetolong-range between grapheneandthecarbidesubstrate.Thereisasimilar of exfoliatedgraphene,asaconsequenceontheinteraction in grapheneonSiC islowerbyanorderofmagnitudethanthat graphene. Itwasfound,forexample,thattheelectronmobility sarily showthesamepropertiesasexfoliatedandsuspended properties ofgrapheneonbasalplaneand(110 Another applicationofgrapheneisinelectrodessuper- As longasgrapheneisattachedtoSiC, itwillnotneces- ciently highgravimetriccapacitancecanbeachieved [ 165 [ 224 [ , 41 223 ] Ithasbeen shown byStolleretal. [ 217,218 , 63 [ ] 226 [ EpitaxialgrapheneonSiC canberemoved 164 ] n orcarbon onions, ] ) steps. ) ] Future researchwillexploreCDC-based usingelectronbeamlithographyorconven- ] Lietal. [ 222 ] Thisisassociatedwithdifferent [ 221 eld effecttransistorscanbe ] showedthatmilimeter-sized Adv. Funct. [ 225 ] gahn nanosheets graphene www.MaterialsViews.com

Mater. [ 205 n ] Reproducedwith ) SiC. )

2011 eld-emission [ [ , 224 221 21 ] ] , 810–833 thata Aniso- FEATURE ARTICLE 827

] 2 3 C − 52 [ ° 0.2

]

] < The 74 This ] [ ] 231 C with [ A total . ] ° 230 230 [ [ 190 [ C. Bulk TiC- Bulk annealing ] ned SiC/C ° 2 74 [ KOH activa- ] 14 wt% excess

a). uptake of 63% uptake of 63% ] carbons, where ∼ 2 100 2 -CDC. [ wileyonlinelibrary.com Figure 13 Figure 74 cial layer for the www.afm-journal.de 3 [ at 800 2 C 0.7 for SiC to 0.7 for SiC C was used to form 4 ° > A later study charac- ] cient, especially during 0.1 in dry nitrogen were uptake. Figure 12 Figure 5% H 2 < + 208,209 [ C ( C. Direct comparison of the ° ° C. C and SiC). The best results The best results C and SiC). C of 0.5 wt%, 1 wt% at –78 C of 0.5 wt%, 1 as shown in 4 ° ] ° cient from 230 [ cients of C was reported. C was reported. studied the pore size effect on hydrogen studied ° ] C and 20 bar, an increase of H C and 20 bar, 100 ° [ Chlorination at 700–1000 ] 75 , lm surface during friction. 62 , Early studies by Gordeev et al. showed that by Gordeev et al. showed that Early studies ed at 1 atm and –196 ed at 1 atm and –196 ] C and 1 atm, KOH-activated ZrC-CDC shows less 38 ° [ They could also function as a sacrifi 227 ] [ 69 [ uptake than as-produced TiC-CDC. Monolithic TiC-CDC TiC-CDC Monolithic uptake than as-produced TiC-CDC. uptake of up to 3 wt% and volumetric density of 24 kg m uptake with and without subsequent TiC-CDC uptake between The hydrogen storage capacity of CDC has also been storage capacity of CDC has The hydrogen Even lower friction coeffi Even CDC coatings were also used to enable pull-out and increase CDC coatings were also used Yushin et al. Yushin cient desorption at 400–1200 cient desorption at 400–1200 2 2 2 cient mechanical strength and a kind of “ductility” (inset in cient mechanical strength and a kind of “ductility” bers. a CDC layer on sintered SiC ceramics and was shown to effec- a CDC layer on sintered SiC tively reduce the friction coeffi under dry running conditions Without activation, TiC-CDC shows values of shows TiC-CDC activation, Without 25 at 35 bar and methane uptake temperatures by using CDC from various uptake at cryogenic ZrC, B carbide precursors (TiC, were obtained for hydrogen-annealed TiC-CDC; a gravimetric a gravimetric TiC-CDC; were obtained for hydrogen-annealed H the presence of water vapors is required for lubricity and dura- The tribological properties of CDC in both wet atmos- bility. pheres and dry environments were explained by the presence of carbon onions, water adsorption in CDC micropores, and termination of dangling carbon bonds with hydrogen. increases the sorption capacity of CDC by 75%. When average increases the sorption capacity of CDC by a linear correlation pore diametre is below 1 nm, there is between the pore volume and the H was demonstrated. compared to as-synthesized ZrC-CDC hydrogen uptake at 1 MPa at 27 MPa hydrogen uptake at 1 studied. behavior is unlike that of graphite and other sp was reported to show improved gravimetric hydrogen storage was reported to show improved gravimetric c, d). 12 capacity compared to powders (Figure hydrogen can be chemisorbed on SiC-CDC at 300–600 at 300–600 on SiC-CDC hydrogen can be chemisorbed effi H hydrogen annealing showed that post-synthesis larger gravimetric H tion is also a suitable method to obtain a terized the hydrogen uptake for SiC- and Al uptake for SiC- terized the hydrogen 4.4. Tribological Coatings Coatings 4.4. Tribological are used in sliding contact applications carbide materials Many and chemical because of their high wear resistance, strength decrease their friction coeffi To stability. The SiC on SiC. dry friction, a carbon coating can be used inward growth of the surface is transformed into carbon by adherent CDC layer giving rise to a tight, well defi interface. H H observed after annealing CDC in Ar ) provided suf- 7 3-dimensional carbon network of CDC (Figure fi ) that prevents brittle fracture and allows “smoothing” 13 Figure of the CDC fi was identifi storage; at –196 –196 At damage tolerance in composite materials applied on SiC fi CDC plates showing an excess uptake of 21 wt% were reported.uptake of 21 wt% were showing an excess CDC plates translates this no macroporosity, bulk CDC has since However, compared to CDC powder. volumetric uptake to a very high and 2 wt% at –196

] ] 41 C, [ ° TAE- C for 228,229 Copy- M [ ° ] . 1 63 [ − or KOH 2 g 2 under the 1 − ) for CDC pow- ] /g at ambient at 975 3 2 Chmiola 2010, g ] 200 [ 3 81 [ 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim GmbH & Co. 2011 WILEY-VCH Verlag © Korenblit, ] The best excess gravimetric ] 203 [ C and 60 bar (16 wt% at 35 bar) 228 Thomberg 2009 [ ° ] 84 [ Shi, ] cient storage of gases such as cient 201 [ , 810–833 layer) (b).Reproduced with permission. 21 2 , Thomberg 2010, ] 2011

202 [ C-derived CDC only shows 10 cm C-derived CDC only reported a sorption capacity of 40 cm 4 ] Volumetric capacitance vs. average pore size in 1.5 Volumetric 227 [ cantly improves the gravimetric methane uptake fromcantly improves -ACN (after Fernandez et al.; -ACN (after Fernandez CDC can be optimized to adsorb a large quantity of methane.CDC can be optimized to adsorb cient in terms of required storage container volumes when 4 2 h, yielding material with a surface area of 3360 m same conditions. CDC outperforms commercially available activated carbons, offering 2.8 wt% methane storage at ambient tem- activation in CO perature and pressure. Post-synthesis signifi et al. as shown by Yeon TiC-CDC hydrogen or methane. Gogotsi compared to hydrocarbon storage. Therefore, materials which show a high physisorption capacity at moderate temperatures are essential for a more effi 4.3. Gas Storage (Hydrogen, Methane) Reversible gas storage is of critical importance in fuel cells and other technologies. Storage of liquid hydrogen requires cryogenic cooling, and compressed hydrogen storage is less effi pressure and temperature for SiC-CDC chlorinated at 1200 pressure and temperature for SiC-CDC whereas B was obtained with a TiC-CDC activated with CO was obtained with a TiC-CDC methane uptake of 18.5 wt% at 25 ders and fi lms of different thickness (a). Example of a CDC fi lm with lms of different thickness (a). Example of a CDC fi ders and fi lm on a Si wafer with fi enhanced volumetric capacitance (TiC-CDC thin thermally grown SiO BF Figure 11 . right 2010, RSC Publishing. right 2010, RSC Publishing. Chmiola 2006, www.MaterialsViews.com Adv. Funct. Mater. Funct. Adv. FEATURE ARTICLE 828 sion. surface andplasticextrusionofthe carboncoatingintoapore. factor 4forthefrictioncoeffi cient wasobserved.TheinsetshowsaSEMimageoftheworn 13. Figure Copyright 2010,Elsevier. wileyonlinelibrary.com (d) uptake. 12. Figure www.afm-journal.de [ 231 ] Copyright 2000,Taylor &Francis. Impact ofCDC coatingonthedryfrictioncoeffi cient ofSiC.Asseen,adecrease [ xes ehn (6 (26 methane Excess 74 ] ItisevidentthatbulkTiC-CDCshowsamuchhighervolumetricgasstoragecapacitythanpowder. Reproducedwithpermission. ° C) (a)andhydrogen(–196 © 2011WILEY-VCHVerlag GmbH&Co. KGaA,Weinheim ° C) (b)adsorptionisothermsalongwithvolumetricexcessmethane(c)andhydrogen [ 231 ] Reproducedwithpermis- reported inseveralstudies Pt/C catalystssupportedonSiC-CDC were 4.5. PtCatalyst onCDCSupport ether solutionofAlCl ture andsubsequentlyannealedinNH trated intheporousCDCatroomtempera- ance. are knowntoshowsuperioroxidationresist- formation ofBNorAl-O-Ncoatings,asboth bonding totheresidualSiC fi coatings withasmoothsurfaceandexcellent able forproducingBNorAl–O–Nbased carbide–CDC transition,thisprocessissuit- form anitridecoating.Duetotheconformal As aresult, compared touncoatedSiC fi modulus wasreportedforCDCcoatedfi values andathreefoldincreaseintheWeibull second step,B pressure andelevatedtemperatures.Asa via chlorinationgastreatmentatambient comprises severalsteps.First, CDCisformed [ 232–233 ] Synthesisofasacrifi > 2 65% higher tensilestrength O Adv. Funct. 3 BN)or0.15Methyl (for 3 Al–O–N)isinfi (for www.MaterialsViews.com

Mater. bers. [ 234

2011 br core. ber ] ad were and [ 233 , ca layer cial 21 ]

, 810–833 bers 3 [ to 234 [ l- 74 ] ]

FEATURE ARTICLE 829

] 11 [ 85% and > and choice ] 86 [ wileyonlinelibrary.com www.afm-journal.de CDC has evolved ] 21 [ because its tunable tunable because its ] cant improvement and cant improvement 9 , , and many other gases , and many other gases 1 2 [ to a designer carbon mate- ] , Cl 15 [ 2 synthesis, 4 Also, templates such as biomor-

] The latter processes produce CDC ]

72 [ during thermal decomposition of sil- ] 79 [ this is a signiﬁ ] 160 [ 55 [

] 237 [ C yielded complete removal of the large cytokine of the large cytokine C yielded complete removal ° removal in 5 and 30 min, respectively. Compared Compared respectively. in 5 and 30 min, removal α bers that can be used for advanced engineering at 800 The ability to control the pore size and pore size dis- The ability to control from blood plasma in less than an hour, with with less than an hour, blood plasma in from ] 3 Virtually any known carbon structure—graphene, Virtually ] α cation. Much potential also lies in gas storage where potential also lies in gas storage where Much cation. 86 [ 4 [ With a large number of different structures and a wide and a wide a large number of different structures With The cornerstone of all current and future applications of 95% TNF- fabric or ﬁ applications. rial. to activated carbons, to activated from a novel amorphous carbon of carbide precursors led to development of a large family of of carbide precursors led to development porous carbons. tribution by varying chlorination temperature tribution by varying chlorination temperature range of properties, CDC is being evaluated for a variety of for a variety of range of properties, CDC is being evaluated researched mate- applications. CDC is now one of the most rials for supercapacitor electrodes shows that CDC offers promise as a sorbent for a variety of as a sorbent for CDC offers promise shows that biomolecules. > The excellent tribo- used in energy or chemical technology. found applications logical properties of CDC coatings have of CDC in Li-batteries sen- in dynamic seals. Applications sors, electronic devices and on-chip power sources are being CDC with the pore size templated by explored. Mesoporous the carbide precursor and well-determined surface chemistry has demonstrated its potential in adsorbing cytokines from blood plasma. CDC will always be a comprehensive understanding of the relationship between carbide structure, carbon synthesis conditions, post-synthesis treatment and the resulting CDC structure and properties. This explains why current research focuses on controlling the nature of the carbide precursors – either by ceramics (PDC-CDC) or by creating using polymer-derived ordered mesoporous carbide as a starting material for CDC processes such as electro- the latter, synthesis (OM-CDC). For spinning can be applied. in NH 5. Conclusions group of materials carbons include a large Carbide-derived amorphous to highly ordered structures ranging from fully by extracting metals or metalloids from that can be produced selective oxida- supercritical water, carbides using halogens, as and other chemistries. Starting tion, vacuum decomposition of SiCl an undesired by-product pore size allows optimization of porosity for any electrolyte. for any electrolyte. pore size allows optimization of porosity be used to opti- The tunability of pore size of CDC can sorption and water mize the carbon for selective molecule puriﬁ for hydrogen CDC shows high volumetric sorption capacity and methane and also for CO icon carbide, as well as discovery of the tunability of the pore icon carbide, as well as discovery of the size. and graphene growth TNF- phic TiC obtained by chemical treatment of carbonized paper, obtained by chemical treatment of carbonized paper, phic TiC have been investigated. nanotubes, diamond, or porous amorphous networks—can nanotubes, diamond, or porous amorphous milestones in be synthesized by this method. The important of CNT formation CDC development were the observation

] 3 234 [ Cl 3 , which β by chlo- 2 AlC cation of bio- 3 Fast removal of Fast ] 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim GmbH & Co. 2011 WILEY-VCH Verlag 236 [ , forming layers of © 4 It can be clearly seen It can be clearly seen ] , IL-6, and IL-1 α annealed ternary carbide annealed ternary carbide 234 AlC and Ti AlC and Ti [ 3 . 2 lm and reach Pt particles lm and reach Pt particles Reproduced with permission. ] While micropores are needed While ] 234 [ 236 , 55 Figure 14 Figure [

] cient for NH C was subjected to annealing in argon, C was subjected to annealing As the carbon nanostructure is barely As the carbon nanostructure ] ° 235 [ , 810–833 234 [ 21 , 2011

CDC derived from Ti CDC derived from Ti ] 55 [ SEM image of a layered Pt-carbon fi lm produced by chlorina- SEM image of a layered Pt-carbon fi AlC-derived carbon obtained by chlorination and annealing ammatory cytokines such as TNF- ammatory cytokines 2 uids, especially given that CDC, as with most other carbons, uids, especially given Copyright 2001, The Electrochemical Society. 2001, The Electrochemical Society. Copyright Figure 14 . tion of SiC in presence of platinum. that reacts with SiC to form Pt and SiCl to form Pt and SiCl that reacts with SiC CDC, because the positively charged aminated surface attracts CDC, because the positively charged aminated mesoporous negatively charged protein molecules. In particular, Ti is necessary to stop the progression of sepsis, was demon- is necessary to stop the progression of strated. It was most effi platinum particles. that the resulting material shows Pt layers which is an inter- that the resulting material interest for catalyst applications. esting structure of potential metal nanopartices can be Besides Pt, other well-dispersed introduced into CDC. rination at 600–1200 ammonia, hydrogen, chlorine and vacuum. infl introduced either by a conventional wet chemical route with wet chemical either by a conventional introduced the nanom- the Pt particle in annealing to control subsequent During during CDC synthesis. size, or directly eters range introduced into the platinum was chlorination, metallic SiC mate- in the produced and effectively dispersed reaction zone interface as gaseous Pt the SiC/C rial by transport toward for supercapacitors and gas storage, sorption of biomolecules, for supercapacitors and gas storage, sorption requires mesoporous which have sizes of several nanometers, is expected materials with a high surface area. Mesoporosity compared to micro- to yield a much higher sorption capacity accessible to protein porosity because of the larger surface area molecules. 4.6. Protein Sorption sorption of ions and mol- CDC shows pore-size dependent the purifi ecules and this property can be used for fl has good biocompatibility. affected by the additional presence of platinum, only small presence of platinum, only small affected by the additional into the fi molecules can penetrate embedded in the CDC structure. An example for such a Pt/C structure. An example for such a Pt/C embedded in the CDC in composite is displayed www.MaterialsViews.com Adv. Funct. Mater. Funct. Adv. FEATURE ARTICLE 830 wileyonlinelibrary.com in Mohun, A. W. [15] Kusunoki, Gogotsi, M. Y. Mochalin, Norimatsu, Y. Osswald, W. S. [7] Yushin , G. Cambaz , G. Vakifahme- C. Z. Fischer , E. [6] J. Gogotsi, Y. Reddington, P. Yeon , S.-H. in Gogotsi, [5] Y. Nikitin, A. Yushin , G. [4] in Gogotsi, Y. Nikitin, A. [3] Gogotsi, Y. [2] Frackowiak , E. Beguin, F. [1] for commentsonthemanuscript. discussions. We arethankfultoR.Swartz,D.Tadros, andJ.McDonough Prof. M.Barsoum,Yoshimura, andProf.B.Etzoldforhelpful collaborators Prof.J.E.Fischer, Prof.P.Simon,M.J.McNallan, Dr. S.-H.Yeon andDr. C.Portetforexperimentalhelp,aswell and post-docs,especially, Dr. J.Chmiola,Dr. R.K.Dash,Dr. G.Yushin, Foundation. YGwouldalsoliketothankhiscurrentandformerstudents acknowledges thefi nancial supportfromtheAlexandervonHumboldt Offi ce ofBasicEnergySciencesunderawardno.ERKCC61.VP Center fundedbytheU.S.DepartmentofEnergy, Offi ce ofScience, Structures andTransport (FIRST)Center, anEnergyFrontier Research YG andVPweresupportedaspartoftheFluidInterfaceReactions, Offi ce forfundingandY-Carbon forprovidingsamples forourresearch. (award numbersICC-0924570,DMR-0945230),andtheArmyResearch ER46473, DE-FGOI-05ER05-01),USNationalScienceFoundation The authorsthanktheUSDepartmentofEnergy(awardnumbers Acknowledgements [1 T X Nue , . . a , . . hta Bhatia, K. S. Bae, S. J. Nguyen, Bhatia, X. T. K. S. [18] Nguyen, X. T. Gogotsi, Bae, Y. S. Fischer , J. J. [17] Jagiello, J. Dash, R. Yushin , G. [16] Ley , L. Kellogg, G. Jobst, J. Horn, K. Bostwick, A. Emtsev , K. [8] [1 P Kaic E Kcrc , . ocad , . egr A Corma , A. Geiger , D. Kaskel, S. Geiger Borchardt , , D. Krawiec , L. P. [20] Kockrick, E. Krawiec, P. [19] Gogotsi, Y. Simon, P. [9] [1 Y G Ggti K G Nce , . osa , Kofstad, P. Nickel, G. K. Gogotsi, G. Y. [12] [2 J N Adre , Andersen, N. J. [22] Hutchins, O. [21] Naud , Suzuki, C. T. Brown, Rokkaku, N. M. Wu , Kusunoki, S. M. X. [11] Li, B. X. Song, M. Z. Berger , C. [10] [1 N F Fdrv Fedorov , F. N. [13] [1 T Koai J Cmoa Y Ggti i in Gogotsi, Y. Chmiola, J. Kyotani , T. [14] www.afm-journal.de CRC Press/Taylor andFrancis , Boca Raton,Fl chemical EnergyStorageSystems Carbon Colombo , P. toglu , Fl Raton Boca Francis , & Taylor CRC Gogotsi), Y. lishers , Valencia, CA technology Raton and Conversion Systems 1046. Mater. 1959 Rotengerg, Seyller E. , T. Weber Röhrl, , B. J. H. Waldmann , Reshanov , D. S. Schmid, K. Ohta, A. T. McChensney , J. 52 . . akl Kaskel, S. 2009 2620 . ao , . . i J Hs , . . acekv Marchenkov , N. A. Hass, J. 1191. Li, B. T. Mayou, D. 2313 , 443. , , , 8

2006

2006 , 203. , 2008 , Vol. J. Phys.Chem.C

, , , , abn Nanomaterials Carbon 16 US Patent1271713 46 Russ. J.Inorg.Chem. , 2288. , US Patent2739041 , 841. , 7 Proceedings oftheConference onCarbon (d H S Nla , Aeia Sini c Pub- Scientiﬁc American Nalwa), S. H. (Ed: Carbon 2004 Nat. Mater. , CRC Press , Boca Raton,Fl Carbons forElectrochemicalEnergyStorage

, 553. , Encyclopedia ofNanoscienceandNano- 2009 2010 , , , , Published online:February 9,2011 , Es . eun, E Frackowiak ), E. Beguin, F. (Eds: , Chem. Comm. , , 113 48

2008 Chem. Phys.Lett. 1918

, , , CRC Taylor &Francis , Boca 1995 , 201. , 1956 Langmuir , 7755. , Carbon MaterialsforElectro- J. Phys.Chem.C abn Nanomaterials Carbon , , . Appl. Phys.Lett. Received: October5,2010 7 , , . , 845. , J. Mater. Chem. 39 , 73. , ©

2011WILEY-VCHVerlag GmbH&Co. KGaA,Weinheim 2009 2009

2006 Science 2006 , 77. , , , , , 25 2009

23 , 211 , , 2121 , Nat. Mater. 2009

Adv. Funct. , 2469 , 2010

2006 1997 .

1995 , Vol. , , , (Ed: , , , , , , , 468 312 114 , , 71 4 5 , , , , , ,

[4 S Ubnie S Wctese , . ige , . ooe , . . Zou, Y. W. Coronel , E. Mirguet, C. Wachtmeister Gavrilov , , S. N. Urbonaite, D. S. Ivakhnyuk, [40] K. G. Fedorov , F. N. [39] in Warnecke , H. H. Boehm, P. Borguet, E. H. Gogotsi, Y. [37] Osswald, S. Kazachkin, D. Portet, C. [36] [4 A N Zlka , . . env , Leonova, M. L. Zelikman, N. A. [49] Vuzov , Izvestiya Zelikman, N. A. Meerson, A. G. Kirillova, F. G. [23] [4 J Cmoa C Lret P L Tbra P Smn Y Ggti Gogotsi, Y. Simon, P. Taberna , L. P. Largeot, C. Chmiola, J. [41] [4 G Luii , . . ah J P Sne , . uhn Y Gogotsi, Y. Yushin , G. Singer , P. J. Dash, K. R. Gavrilov , Laudisio, N. D. G. Ivakhnyuk, [44] K. G. Fedorov , F. N. [43] Gogotsi, Y. Nikitin, A. Dash, K. R. [42] Lee, A. Welz , S. McNallan, J. M. Kovalchenko, A. Erdemir , A. [38] [5 M Svla R Fuso , . oaa Mokaya, R. Foulston , R. Sevilla , M. [52] Gogotsi, Y. Yushin , G. Dash, K. R. Gogotsi, [51] Y. Dash, R. Yushin , G. Chmiola, J. [50] Starobina, M. T. Zelikman, N. A. Seryakov , Barsoum, V. W. G. M. Ye Orekhov , , H. P. Nikitin, V. A. [25] Hoffman, N. E. Yushin , N. G. [24] [4 K Mtflt M Seno i in Steinmo, Svensson, M. G. Motzfeldt, Käärik, K. M. Arulepp, [47] M. Perkson , A. Leis, J. [46] McNallan, M. Zhu, Y. R. Lee, A. [45] [5 G Ysi , . . ofa , . . asu , . oos , . . Howell, A. C. Gogotsi, Y. Barsoum, W. Fischer , M. Hoffman , E. N. E. J. Yushin , G. Hoffman, [55] N. E. Dash, K. R. Yushin , G. Chmiola, Lust, J. E. [54] Thomberg, T. Jänes, A. [53] [2 A K Kraoe J L Mrrv , Margrave, L. J. Kuriakose, K. A. [26] [4 S Wl , . . caln Y Ggti Gogotsi, Y. McNallan, J. M. Welz , S. [48] [2 A K Kraoe J L Mrrv , Margrave, L. J. Kuriakose, K. A. [27] [2 H Wn , . a , Gao, Q. Fedorov Wang , , H. F. N. [29] Ivakhnyuk, K. G. Babkin, E. O. [28] [3 G K Iahyk O E Bbi , . . eoo , Fedorov , F. N. Babkin, Gogotsi, E. Y. O. Barsoum, Ivakhnyuk, W. K. G. M. [35] Yushin , Spinelle, G. Hoffman, L. N. Hamwi, Barsoum, E. W. M. [34] A. Gogotsi, Y. El-Raghy , T. Dubois, Yushin , G. Hoffman, M. N. E. Guerin, [33] K. Batisse, Aronson, N. R. [32] J. Schumb, C. W. [31] [3 Z G Cma , . . uhn Y Ggti K L Vyshnyakova , L. K. Gogotsi, Y. Yushin , N. G. Cambaz , G. Z. [30] . sla , . tvnsn Stevensson, G. Csillag, S. 1982 Carbon mochim. Acta 67 2006 Tsvetnay , . . ice , Fischer , E. J. 1982 2004 2010 Carroll , B. Gogotsi, Y. 2005 158 Sverchkov , M. P. Petrova, V. K. Kahzanova, I. T. Gogotsi, Y. Conference onHighTemperature MaterialsChem. 2001 S1763. . . admn G J Pilp , . . ly , . . ihlvk , Mikhalovsky , V. S. Lloyd, W. A. Phillips, J. materials G. Sandeman, R. S. A357. Gogotsi, Y. Barsoum, W. M. 223. 1969 . . pa ) h Eetohmcl o. Ic enntn N NJ Pennington, Inc., Soc., 523. Electrochemical The Spear), E. K. 57 Mater. MicroporousMesoporousMater. Tomasella , E. . . eeeetea Pereselentseva, N. L. , 2052. , , 504. , , 765. , , , , , , , , , , , , , , , 55 179 55 72 328 86 39 42

, Prao xod Oxford Pergamon, , 2005 , 243. , , 40. , 203. , , 50. , , 2043. , , 230. ,

2006 Metallurgiya , 11. , , 480. , Carbon , , Langmuir 17

Thin SolidFilms 2010 , , , 2317. , 27 , 5755. ,

Carbon , , 2005 497

J. Am.Ceram. Soc. Surf. Coat. Technol.

1960 2006 , 137. , , , 43

2009 Carbon , , , 2075. , , , 1975 3 22 Electrochem. Solid-StateLett.

, 90. , J. Am.Chem.Soc. 2010

, , Proceedings ofthe9thInternational , 8945. , Carbon 2008 J. Phys.Chem. J. Phys.Chem. Tsvetn. Met. 47 J. Phys.:Condens. Matter , 149. ,

2007 , 820. , Adv. Funct. , , Microporous MesoporousMater. Microporous MesoporousMater. 518 , , Proc. 12thBiennialConf. on Energy Environ.Sci. 112 J. Mater. Process.Technology

, , 2007 , 6746. , 45

2006

, 526. , 2004 www.MaterialsViews.com , 2047. ,

, ,

1978 J. PowerSources Mater. 45 , ,

1964 1964 , , Zh. Fiz.Khim. 89 Zh. Prikl.Kh. , 2717. , 188–189

1959 , 509. , , , , Vol.

19 Zh. Prikl.Khim. 2011 , , , , Zh. Prikl.Khim Zh. Prikl.Khim 68 68 , 54. , , , , 2343. , , 290. , 81 , 97–39 , 588. , 21

, 806. ,

2006

, 810–833 2010 2005 Science Carbon Chem.

2006 1997 1983 1993 (Ed: Ther- , , Bio- , , , , 18 3 8 , , , , , , ,

FEATURE ARTICLE 831

, , , , , , , , , 14 44 93 . , , , 1995 1991 1995 2001 2002

J. Am.

2004 Zh. Prikl. Diamond 2004 , 4357 . 2006

2003 , 755 .

Adv. Funct. Funct. Adv.

33 14 , Nature , , 595 . J. Mater. Chem. J. Mater. 6 , C160 . , (Eds: S. Kaskel , , Carbon 1998 , 39 .

64 1995 wileyonlinelibrary.com

, 628 . , 628 . , www.afm-journal.de 10 US Patent 6697249 J. Mater. Chem. J. Mater. J. Mater. Chem. J. Mater. , 1996

367 367 , , 1981 J. Mater. Chem. J. Mater. J. Appl. Phys. J. Non-Cryst. Solids J. Non-Cryst. .

J. Am. Ceramic Soc. J. Am. Ceramic 1994

1994 1994

2002 J. Mater. Sci. J. Mater. , , 582 . Handbook of Ceramic Hard Mate- Handbook of Ceramic , 133 . , 1116 . 25 , 581 . 5 , 1729 . Nature MRS Bull. Nature Sci. Lett. J. Mater. , , J. Mater. Chem. J. Mater. 48 35 41 , , , , 217 . 2009

2003

2010

J. Am. Ceramic Soc. J. Am. Ceramic 1997 2003 Advanced Multilayered and Fibre-Reinforced 1998

WO 02/39468 , 1851 .

, 151 .

5 77 , , , p5 6 . , 2288 . Carbon Langmuir , 1719 . Carbon Characterization of Porous Solids VIII Solids VIII of Porous Characterization Patent Carbon 1996 16

1994 57 ,

2009 , (Ed: Y. M. Haddad ), Kluwer Academic Publishers , (Ed: R. Riedel ), Wiley-VCH , Verlag Weinheim, Germany , 1 Solid State Sci. , 1039 . , 810 . 2006

10 1984

, . , 374 . , Vol. , Vol. , 283 . , 1269 . , 595 , 595 . 5 rials 74 5 238 . A. D. Lueking , Mater. Relat. Mater. G. E. Khomenko , K. Skjerlie , Ceram. Soc. Ceram. 2000 S. Lidin , G. Svensson , 2122 . S. G. , Kozachkov J. V. A. G. Kukusjkina , Danilin , A. J. S. E. N. Kravtjik , Zheng , , V. Podmogilny C. V. M. L. , Sokolov S. , Wallace A. Arulepp , Perkson , K. J. Leis , , Gordeev S. , Podmogilny V. J. , Danilin J. , Kolotilova V. , Izotov Y. J. G. S. K. Konstantinovich , , Kolotilova , Aleksandrovna V. M. S. J. Arulepp , , Vasilevitj J. A. , Cederstrom Leis , K. C. Eﬁ L. Movitj , , Wallace A. J. Perkson , Zheng , 2004 K. E. Gubbins , Y. Gogotsi , in P. , Llewellyn F. , Rodriguez-Reinoso N. Cambridge A. Seaton ), RSC Publishing , 411 O. , Marty S. , Gordeev A. , Grechinskaya 4207 . Khim Composites Composites Dordrecht, Germany 2000 299–302 [ 114 ] K. G. Nickel , Y. G. Gogotsi , in [ 112 ] G. Perera , R. H. Doremus , W. [ 113 ] Lanford , N. S. Jacobson , Y. G. Gogotsi , M. , Yoshimura [ 111 ] S. Ito , M. , Tomozawa [ 99 ] K. W. Adu , [ 100 ] S. G. C. , Yushin R. Desai , , Dash J. A. Jagiello , J. N. E. , , Fischer Sidorov Y. , Gogotsi G. U. Sumanasekera , [ 108 ] Y. G. Gogotsi , K. G. Nickel , D. [ 109 ] , Bahloul-Hourlier S. T. Merle-Mejean , Kitaoka , T. , Tsuji T. Katoh , Y. , Yamaguchi K. Kashiwagi , [ 110 ] N. S. Jacobson , Y. G. Gogotsi , M. , Yoshimura [ 95 ] H. P. Boehm , [ 96 ] M. Jacob , U. Palmqvist , P. C. A. Alberius , T. [ 97 ] C. Ekström , M. A. Nygren , Perkson , J. [ 98 ] Leis , S. Dimovski , A. M. Nikitin , H. , Ye Arelupp , Y. Gogotsi , M. Käärik , S. Urbonaite , [ 102 ] Y. A. Maletin , N. G. Strizhakova , V. G. , Izotov A. A. Mironova , [ 103 ] Y. Maletin , N. Strizhakova , S. , Kozachkov A. , Mironova [ 104 ] J. Leis , M. Arulepp , A. Perkson , Patent WO/2004/094307, [ 105 ] Y. G. Gogotsi , M. , Yoshimura [ 106 ] Y. G. Gogotsi , M. [ 107 ] , Yoshimura Y. G. Gogotsi , P. Kofstad , M. , Yoshimura K. G. Nickel , [ 88 ] J. C. , Palmer A. Llobet , S.-H. , Yeon [ 89 ] J. E. J. , Fischer C. Y. Shi , , Palmer Y. Gogotsi , S. J. Jain , K. E. Gubbins , J. E. [ 90 ] , Fischer R. Y. G. K. Gogotsi , Dash , S. , Welz D. A. [ 91 ] , Ersoy M. E. , Smorgonskaya J. R. McNallan , , Kyutt A. Danishevskii , C. Jardin , R. Meaudre , [ 93 ] O. E. Babkin , G. K. Ivakhnyuk , Y. N. [ 94 ] Lukin , N. J. F. , , Zheng Fedorov T. C. Ekström , S. K. , Gordeev M. Jakob , [ 101 ] J. Leis , M. Arulepp , A. Kuura , M. Lätt , E. Lust , [ 118 ] Y. G. Gogotsi , in [ 117 ] T. Kraft , K. G. Nickel , Y. G. Gogotsi , [ 115 ] Y. G. Gogotsi , M. [ 116 ] , Yoshimura Y. G. Gogotsi , M. , Yoshimura [ 92 ] S. , Welz Y. Gogotsi , M. J. , McNallan

, , , , , , , , , , J. y , 7 91 55 62 43 33 48 , 113 Eng. , , , , , Phys. , 2005 1984

Micron , J. Phys. 1997

, 3 . 2010 1997 2005 2008 2010

, 242 .

2010

2008 47 ,

Ceram. Eng. Sci. Ceram. Carbon 338–342 Carbon 2009 ,

Microporous Meso- New Carbon Mater. New Carbon Electrochem. Comm. Electrochem. , 3501 . Appl. Phys. Lett. 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim GmbH & Co. 2011 WILEY-VCH Verlag Proc. Electrochem. Soc. Mater. Res. Innovations Mater. , 1447 . 39 2000 ©

J. Mater. Chem. J. Mater. , 42 Carbon , 603 . , Tsinghua Sci. Technol. Tsinghua , 7755 . 57 Surf. Coat. Technol. Surf. Coat. 2004 Electrochim. Acta

, , 591 . 2004 2

113 , J. Min. Met. Mater. Soc. J. Min. Met. Mater. , , 543 . 1985

, 701 . 14 , 1337 . 2003 , 2009

Carbon , 191 , Mater. Sci. Forum Mater. Crit. Rev. Solid State Mater. Sci. Solid State Mater. Rev. Crit. J. Mater. Sci. J. Mater. 2010 , 423 . , 236 .

, 135 .

2010

4 1961 and , J. Applegate , R. Nolte , E. , Cortes 131 159

, 2314 . , , 7561 . , , Microporous Mesoporous Mater. , 810–833 42 Nat. Mater. , 3263 . , 21 114 2011 ,

Pure Appl. Chem. , 57 . 2010 , 2010 44

Nature , , 324 . J. Phys. Chem. C 24 2000 ACS Nano

, 2011

2010 , 243 . , 335 .

2006 , 313 . , 55 .

6 24 38 5 98–99 2003 , , , , ,

, 700 . , 699 . 3138 . Solid State M. W. Barsoum , 2004 Carbon D. Henshall , , V. J. Tsvetkov C. , Carter , Jr. , Jenny R. Leonard , D. Malta , S. G. , Müller G. , Svensson 14 . 2009 S. Kaskel , 44 . G. , Yushin 978 . Y. Gogotsi , A. , Erdemir A. , Kovalchenko & Environ. Sci. Solid State Electrochem. 10 J. D. , Hettinger P.-L. , Taberna P. Simon , P. , Huang M. Brunet , 69 . Chem. A 2007 Herrero , A. R. , Landa-Canovas L. C. Otero-Diaz , A. Gomez-Herrero , A. R. , Landa-Canovas L. C. , Otero-Diaz 1 . 403 . 45 porous Mater. 2001 1841 . Chem. Eng. J. Proc. 1998 [ 85 ] S. K. , Gordeev S. A. Kukushkina , A. V. , Osipov Y. V. , Pavlov [ 86 ] Y. Gogotsi , A. Nikitin , H. , Ye W. Zhou , J. E. , Fischer B. Yi , H. C. Fole [ 78 ] N. , Popovska M. Kormann , JOM [ 84 ] T. Thomberg , A. Jänes , E. Lust , [ 77 ] W. Pabst , E. Gregorova , [ 56 ] A. , Jänes L. , Permann M. [ 57 ] Arulepp , A. E. E. , Kravchik , Lust J. A. Kukushkina , V. V. , Sokolov G. F. , Tereshchenko [ 64 ] D. Hobgood , M. , Brady W. Brixius , G. , Fechko R. Glass , [ 65 ] J. , Tang J. S. Zabinski , J. E. Bultman , [ 87 ] S. Urbonaite , J. M. Juárez-Galán , J. Leis , F. Rodríguez-Reinoso , [ 83 ] P. Krawiec , E. Kockrick , L. , Borchardt D. , Geiger A. , Corma [ 79 ] M. , Kormann H. [ 80 ] Gerhard , N. K. Popovska , S. W. Sing , [ 81 ] Y. Korenblit , M. Rose , E. Kockrick , L. Borchardt , A. , Kvit S. Kaskel , [ 82 ] G. Cheng , D. H. Long , X. J. Liu , L. C. Ling , [ 61 ] Y. , Xiong Y. Xie , [ 62 ] X. Li , M. Z. Li , , McNallan D. , Ersoy R. Zhu , A. Lee , C. White , S. , Welz [ 63 ] M. Heon , S. Loﬂ [ 58 ] M. , Lätt M. Käärik , L. , Permann H. Kuura , M. Arulepp , J. , Leis [ 66 ] T.-H. , Wang A. M. Navarette-Lopez , [ 67 ] S. Y. Li , G. Gogotsi , D. I.-D. A. Jeon , M. Dixon , J. McNallan , [ 60 ] E. Urones-Garrote , D. , Avila-Brande N. , Ayape-Katcho A. Gomez- [ 59 ] D. , Avila-Brande E. Urones-Garrote , N. A. Katcho , E. Lomba , [ 75 ] D. A. , Ersoy M. J. McNallan , Y. Gogotsi , in [ 72 ] M. Rose , E. Kockrick , I. [ 73 ] Senkovska , J. S. A. H. Kaskel , da , Jornada S. Block , G. J. [ 74 ] Piermarini , S.-H. , Yeon I. Knoke , Y. Gogotsi , J. E. , Fischer [ 71 ] V. , Presser K. G. Nickel , [ 70 ] D. A. , Ersoy M. J. McNallan , Y. G. , Gogotsi [ 68 ] P. F. , Becker F. Glenk , M. Kormann , N. Popovska , B. J. M. Etzold , [ 69 ] L. Chen , G. Behlau , Y. Gogotsi , M. J. McNallan , [ 76 ] F. J. Norton , www.MaterialsViews.com Adv. Funct. Mater. Funct. Adv. FEATURE ARTICLE 832 [11] . . ioe , . . or , . rn M J Pli , Pellin, J. M. Hryn, J. Moore, F. J. Zinovev , V. A. Kusunoki, M. [141] Morokuma, K. Zheng, S. G. Wang , Z. Irle, S. Leibenzeder [140] , S. Lanig, P. Stein, A. R. [139] Loyen, J. G. Meyer , F. [137] Badami, V. D. [136] Comer , J. [135] [12] . uuoi T Szk , . iaaa N Siaa Shibata, N. Hirayama, T. Suzuki, T. Kusunoki, M. [142] Pensl, G. Matsunami, H. Choyke, J. W. [138] Iijima , S. [134] Badami, V. D. [133] [16] . uuoi T Sio Y Iuaa Ikuhara, Y. Saito, T. Kusunoki, Kaneko, M. K. [146] Shibata, N. Hirayama, T. Suzuki, T. Kusunoki, M. [145] Ito, M. Kaneko, K. Suzuki, T. Hirayama, Kusunoki, T. M. Rokkaku, [144] M. Shibata, J. Kusunoki, M. [143] wileyonlinelibrary.com Lal, K. Dayananda, S. A. Madhusudan, P. Basavalingu, Gogotsi, B. G. Y. [124] Byrappa, K. Calderon-Moreno , M. J. Basavalingu, B. [123] Nickel, G. K. Kraft, T. [119] [19] . ot , . iri L Aiyn L D Dmncs F Fabbri , F. Dominicis, Tanaka , De N. Mukainakano, L. S. Hisada, Asilyan, Y. Watanabe , L. A. Ciardi, [150] R. Botti, Sakakibara, T. S. Yatsuki , [149] M. Miyano, R. Takikawa , H. [148] Shibata, N. Nagano, T. Kusunoki, M. Ishikawa, Y. Shimizu, T. [147] [16] . . ooaoa abds. Carbides . Kosolapova, Y. T. [126] in Yoshimura , M. Libera, A. J. Gogotsi, Y. [125] Raisch , C. Wang , X. Nickel, G. K. Berthold, C. Presser , V. Zhang, H. in Gogotsi, [122] G. Y. Kraft, T. Nickel, Breval, G. E. K. Badzian, [121] A. Ravichandran, D. Roy , R. [120] [11] . aao Y Ihkw , . oioh , Noriyoshi, S. Ishikawa , Y. Nagano, T. [151] [11] . ru , . uc , Busch, G. Braun, A. [131] Busch, G. [130] Bresker , I. R. Kuznetsova, L. V. Stumpf,T Voronin , I. C. N. H. [128] Long, G. Foster , M. L. [127] [14] . hitasn R Hli , Helbig, R. Christiansen, K. [154] O’Neill, G. A. Johnson , Morokuma, M. C. K. Wright , G. Kusunoki , N. M. [153] Zheng , G. Irle, S. Wang , Z. [152] [12] . ue , . . zrisy i in Czerlinsky , R. E. Euler , F. [132] in Bresker , I. R. Kuznetsova, L. V. Voronin , I. N. [129] www.afm-journal.de Phys. B11 2242. Advances Phys. Lett. 79 Phys. 323 . yap , . ohmr , Yoshimura , M. Byrappa, K. Yoshimura , M. . radci A Foi Fiori, A. Orlanducci, S. Phys. Part2-Lett. Appl. Phys.2 9 2001 Nanotechnology Zhou, Y. He, L. Chasse, T. Materials Mater. 2001 . . rnsvc ) oslat Bra e Yr York New Bureau, Consultants Frantsevich ), N. I. 1958 York New Press, Plenum B61–62 Chem. C 1380. . mles , Prao Pes, Ofr Oxford Press , Pergamon Smiltens), J. Semiconductor. ProceedingsoftheConference 22. , 248. , , 153. , , 296. , , 69. , , 253. , , , , ,

2006 1998 203 43

1996 , 468. ,

, 285. , , Srne eln Berlin Springer , , , E: . idl , Wly, Wihi, emn Germany Weinheim, Wiley , Riedel), R. (Ed: , 2007 J. SolidStateChem. , 40. , J. Appl.Crystallography

Helv. Phys.Acta , , , , 2000 125 37 , ,

5 2000 , , , L605. , , 973. , Nature Carbon 111 Carbon , 044702. , , , , E: . sw ) lwr, Drrct Germany Dordrecht, Kluwer , Osawa), E. (Ed: ,

77 1998 , , , 12960. , , 531. , 39 Helv. Phys.Acta

J. Mater. Chem. , L1057. , 1962 1965 Acta Electronica , ,

2001 37 Chem. Phys.Lett. 1971 , L187. ,

2004 J. Am.Ceramic Soc. 1946 , , , , J. Appl.Phys. J. Mater. Sci. Properties, Production,andApplications , , 193 3

39 , 53. , 1982 Silicon Carbide. AHighTemperature . . , 1763. , , , , 569. ,

1971 19 Jpn. FineCeram. Center Rev. , , , 167. , 42

1947

, , 2000 Mater. Sci.andEng.B 1975 , 101. , Silicon Carbide. RecentMajor 4 Jpn. J.Appl.Phys. 1960 Handbook ofCeramic Hard

, 12. ,

1996 2008 2004 he AmericanMineralogist , , , , 20 , , esetvs n Fullerene in Perspectives Mater. Sci.Eng.B Philos. Mag.Lett. 10 , 155. , © 18 , Es J R O’Connor , R. J. (Eds: , , 33 , , , , ,

, , 2011WILEY-VCHVerlag GmbH&Co. KGaA,Weinheim , 671. , Ogneupory 2010 79 43 , 33. , Surf. Sci. 400 iio Carbide Silicon , 3276. , , 2153. , 1970 , 264. , Diamond Relat. Physica B , , 93 2000 Jpn. J.Appl. Jpn. J.Appl. , 81. , , 1148. ,

2006 J. Microsc.

2003 1965 J. Chem. , 374. , J. Phys.

Jpn. J. , , 1992 2002 1999 1997 1999 , (Ed: , Appl. , , , , 600 42 30 , , , , , , , , ,

[15] . . ia S Goh E P Pktlv A A Blni , Balandin, Peeters, A. M. F. A. Partoens , Pokatilov , B. P. [176] E. Ghosh, S. Nika, Stiles, L. D. M. D. Jarvis, A. [175] A. E. Crain , Riley , N. J. D. Guisinger , P. J. N. Rutter Ley , , M. G. L. Seyller , [174] T. Speck, Garreau, F. Y. Emtsev , V. Thibaudau, K. F. [173] Argunova, T. Coati , A. Charrier , A. [172] [11] . aco , . eg J Hs , . i B N Nue , . Naud, C. Nguyen, N. B. Li, X. Hass, J. Feng , R. Varchon , Tromp , F. M. R. [171] Capano , Hannon, A. B. M. J. Biedermann, B. [170] L. Harrison, Avouris E. , S. P. Bolen, Ross, I. M. M. F. [169] Radosavlejevic, M. Martel, R. Derycke, V. Hellgren, A. [168] N. A. Glans, A. P. Johansson, I. Tringides L. , M. [167] E. Conrad , H. E. Hupalo, M. Dai, [166] Z. Feng , Sutter , R. P. Obgbazghi, [165] Y. A. Li, X. Li, T. Song, Z. Cousseins , Berger , Johansson, J.-C. C. Djurado, I. [164] D. L. Hamma, A. Yakimova , Mouras, R. S. [163] Syväjarvi, M. Virojanadara, C. Mc-Chesney , [162] L. J. Mun, S. B. Zhou, Y. S. Gweon , G.-H. Tooren Rollings, , Van E. A. [161] Crombeen , E. J. Bommel, Van J. A. [160] [16] . . . e eqia Mesquita, de H. A. G. Chaussende, [186] D. Vicente, P. [185] [17] . . aMl R L Me-ad J L Tdso C R Eddy , R. C. Tedesco , L. J. Myer-Ward , L. R. VanMil , L. B. [177] [14] . wa , . aln P Mreso , . azn Janzen, E. Martensson, P. Hallin , C. Owman, F. [184] Wee , S. T. A. Chen, S. Chen, W. Huang, H. [179] [18] . . rm , . . ann Hannon, B. J. Tromp , M. R. [178] [11] . . rm M Bnmr , . kwosi W J Everson , Kao, J. H. C. W. Lin, C. Y. Skowronski , [183] M. Benamara, M. Grim, R. J. [181] Sudarshan, S. T. Lari, B. M. Chandler , C. T. [180] Janutunen, H. Juuti, J. Palosaari, J. Halonen, N. Mäklin, J. Toth , Gogotsi, Y. G. Swadener , G. [159] J. Kalidindi, R. S. Cambaz , G. Z. Pathak, S. [158] Stroscio, Wetherington , A. M. J. Cavalero , R. Berger , Trumbull , C. K. Weng Seyller , , X. T. Robinson, Heer , J. De [157] A. Nishigaki, W. S. First, Naitoh, N. M. P. Toyama , [156] N. Matsuoka, H. Konishi, H. [155] [12] . iuh , . aaah , . ua S Szk , . ad , Bando, Y. Suzuki , S. Suga, T. Takahashi , Y. Kikuchi, M. [182] Lett. Stroscio, A. J. First, N. P. Li, T. Sauvage-Simkin, M. 2008 Debever , M. J. Forbeaux , Themlin, M. J. I. Pinchaux, R. . alt J-. eiln C Bre , . . ord L Mgu , Magaud, L. Conrad , H. E. Berger , Rev. Lett. C. Veuillen , J.-Y. Mallet, P. Rev. B NanoLett. 288. 041401R. Heer , De A. W. First, N. P. Chem. B Conrad , H. E. Marchenkov , N. A. Miner. Balasubramanian, T. Zakharov , A. A. Lanzara, A. Heer , de A. W. First, N. P. Fedorov J.Phys.Chem.Solids , V. A. Hussain, S. B. 48 Ajayan, P. Vajtai , R. 2054. Sawyer , G. W. Kordas, K. . . it D K Gsil Gaskill, McCrate , K. M. J. D. Campbell , M. Kitt, P. Culbertson, A. C. S. J. Jernigan, G. G. 1996 211. Ceram. Soc. Heydemann , D. V. 338–342 2513. Carbon Snyder , D. Fanton , M. Hughes, 2010 Z. Labella, M. Frantz , E. Moon, J.-S. Kusunoki, M. , 463. ,

, , , , , , 2010

77 167 4

2009 1987

, 153. , 2009

, 845. , , 155303. ,

2004 2007 , 391. , Nat. Mater. , ,

2002 94 , ,

, , MRS Bulletin 1992 , , 80 24 , 203131. , 47 , , Thin SolidFilms , 99. , J. Appl.Phys. , 115433. , 108 , 572. , , , , 1969. , , , 2 75 , 1043. , , 19912. , Semicond. Sci.Technol.

Int. J.Adv. Manuf.Technol. , 189. , 2006

2009 Acta Crystallog.

2010 , , , , 67 Phys. Rev. B

II-Vs Review 8 Phys. Rev. B Phys. Rev. Lett. 2002 , 171. , , 2172. , Mater. Sci.Forum

, , 2004 Phys. Rev. B 35 , , , 296. , 92 Adv. Funct. , , 464 , 2479. , Phys. Rev. B

1967

2006 2002 , 295 , 2008

www.MaterialsViews.com 2006

, 610. , Mater. Sci.Forum 2007 2009

Phys. Rev. B , , Mater. , , , , Adv. Mater. 74 15 77

ACS Nano , , Surf. Sci. 2005 , , , , , 075404. , 21

, 46. , , 241404. ,

2008 76 102

2009 , 1709. , 2011 J. Cryst. Growth Surf. Sci. , 235416. , , , , 106104. , 25 , , Phys. Rev. B , 78 , ,

, 33. , Appl. Phys. Rev. Chim. 21 1998 ACS Nano

2001 2009 , 245403. , 615–617 , 810–833 2009 J. Phys. J. Am.

, , 1975 2000 Phys. Phys. , , , , 405 , , 80 21 2 , , , , , , ,

FEATURE ARTICLE 833

, , , , , , 1 8 31 , , 329 306 , 2001 , ,

. 2008 2004 J. Power

2010

Phys. Rev. Phys. Rev.

2004 2010 2007

, 1830 .

Tribol. Trans. Tribol. IEEE Electron 86 US Patent US , , 641 Appl. Phys. Lett. 5 , Science Nano Lett. Science wileyonlinelibrary.com , 286 . www.afm-journal.de 2003

Biomaterials , 1226 . 2010 207

, J. Electrochem. Soc. 45 , 16006 . IEEE Electron Device Lett. , IEEE Trans. Electron Devices IEEE Trans. 127 2010

, 2007

, 44 . 2005

13 , Int. J. Appl. Ceram. Technol. Int. J. Appl. Ceram. , 1012 . Carbon J. Am. Ceram. Soc. J. Am. Ceram. Nat. Nanotechnol. 130 2010

, , 51 . , 282 . . 15 , 2008 28

, 560 . , 2010 Phys. Status Solidi (A) , 096802 . . 2003 191

J. Am. Chem. Soc. , 2007

Mater. Today Mater. 101 , , 062111/1 . , 809 . , 2078 . , 650 . 2009

96 43 55 30 2008 , , , ,

, C774 . S. Sandeman , G. Phillips , S. V. , Mikhalovsky 2010/0285392 4789 1637 . J. E. , Fischer 148 666 . Device Lett. W. A. de , Heer 2010 Lett. Y. Y. Miyata , H. Kataura , K. , Tsukagoshi Y. , Aoyagi 2000 68 . A. , Jacobsen S. K. , Ensslin , Hellmüller T. , Frey S. , M. Dröscher , Sprinkle C. C. , Berger , Stampfer W. 2008 A. de , Heer P. M. R. , Myers-Ward , Campbell C. , Eddy 2009 G. D. K. Jernigan , Gaskill , J. S. L. V. Dobonos , , Tedesco I. V. B. Grigorieva , A. , VanMil A. , Firsov 3498 . P.-L. , Taberna P. Simon , J. E. , Fischer Sources M. Á. Lillo-Ródenas , A. Linares-Solano , J. Am. Chem. Soc. Lett. Tribology [ 236 ] S. , Yachamaneni G. , Yushin S.-H. , Yeon Y. Gogotsi , C. Howell , [ 237 ] A. Jänes , H. Kurig , E. Lust , [ 227 ] Y. Gogotsi , R. K. Dash , G. , Yushin T. Yildirim , G. Laudisio , [ 235 ] Y. A. Elabd , Y. Gogotsi , B. Eirich , D. Shay [ 220 ] M. Lemme , T. J. , Echtermeyer [ 221 ] M. X. Baus , Li , H. X. Kurz , , Wu M. Sprinkle , F. Ming , M. Ruan , Y. Hu , C. , Berger [ 223 ] K. I. Bolotin , K. J. Sikes , J. [ 224 ] Hone , M. H. D. L. , Stoller , Stormer S. P. Park , Kim , Y. Zhu , J. An , R. S. Ruoff , [ 226 ] J. R. , Miller R. A. , Outlaw B. C. , Holloway [ 222 ] S. Odaka , H. Miyazaki , S.-L. Li , A. , Kanda K. Morita , S. , Tanaka [ 232 ] L. Chen , H. , [ 233 ] Ye Y. Gogotsi , L. Chen , H. , Ye Y. Gogotsi , [ 234 ] D. A. , Ersoy M. J. McNallan , Y. Gogotsi , [ 215 ] B. A. Anderson , [ 216 ] E. J. T. Nowak , US , Ihn Patent US007732859, J. , Güttinger F. , Molitor S. [ 217 ] J. , Schnez Kedzierski , E. , P.-L. Schurtenberger Hsu , P. , Healey [ 218 ] P. J. W. Wyatt , S. C. Moon , L. Keast , D. Curtis , M. [ 219 ] K. Hu , S. , Novoselov A. D. K. , Geim , Wong S. V. C. , Morozov D. McGuire , , Jiang Y. Zhang , [ 225 ] D. Pech , M. Brunet , H. Durou , P. Huan , V. Mochalin , Y. Gogotsi , [ 228 ] S.-H. , Yeon S. , Osswald Y. Gogotsi , J. P. , Singer J. M. Simmons , [ 229 ] S. Ma , D. Sun , J. M. Simmons , [ 230 ] C. D. B. , Collier , Carroll D. Y. , Gogotsi , Yuan H.-C. A. Zhou , Kovalchenko , A. , Erdemir [ 231 ] M. J. D. McNallan , A. , Ersoy M. J. McNallan , Y. Gogotsi , A. , Erdemir , , , J. J. J. 23 155 562 Elec- , 55 . , Phys. , , Angew. Angew. J. Appl. Electro- 630 J. Alloys J. Alloys , 2008 , 38 . 2008

2004 , 1375 . , 1080 . , 1178 .

17 , 67 67 64 2009 , L87 .

, , , , 273 . 603 2010

1 , 1994 1994 1991 ,

2008

, 2489 . , 2730 . , 1460 . 2005 44 , J. Electrochem. Soc. 130 162 , 37 . , 1633 . , , J. Electroanal. Chem. Surf. Sci. 91 , 1760 . , 820 . , 815 . J. Electroanal. Chem. 41 Zh. Prikl. Khim Zh. Prikl. Khim Zh. Prikl. Khim , 2006 Nano Res.

, 2008 2006 , 4943 .

313

IEEE Trans. Power Electron. IEEE Trans. , A7 . , 2000 11

1996

, 156 Carbon 299–302 299–302 , 670 . , 3392 . , , 7111 . 2006 , , Electrochem. Soc. Interface

47 , 7489 . 53 2009 ,

, 2009 55 , 810–833 2002 2002

, . , . 034305/1 21 330–332 Science , 2008 2008

, J. Power Sources 107 2010 2008

, J. Am. Chem. Soc. 2011 J. Power Sources

2002 Electrochim. Acta

2010

. R. I. G. Uhrberg , A. A. , Zakharov Phys. A531 . trochim. Acta 1526 . J. , Fischer S. , Kucheyev Electrochem. Soc. chem. Acta Chem. Chem. Phys. P. L. , Taberna Compd. Chem Int. Ed. P. Simon , A. F. Burke , 33 . B. A. , Zelenov T. A. V. , Mazaeva E. O. Kravtjik , 2000 S. V. , Pankina P. V. , Kuznetsov V. , Sokolov J. US A. Patent Kukusjkina , 6110335, L. M. , Tuhkonen Solids S. Non-Cryst. K. , Gordeev M. A. , Yagovkina T. Ekström , L. M. , Tuhkonen S. K. , Gordeev M. A. , Yagovkina T. Ekström , Non-Cryst. Solids Non-Cryst. 20070118, [ 187 ] C. , Virojanadara R. , Yakimova J. R. Osiecki , M. Syväjärvi , [ 188 ] Z. Ni , Y. , Wang [ 189 ] T. , Yu R. Z. , Shen , Yang Q. S. Huang , X. L. Chen , G. Y. Zhang , H.-J. Gao , [ 200 ] T. Thomberg , A. Jänes , [ 201 ] E. J. Lust , A. , Fernandez M. Arulepp , J. Leis , F. Stoeckli , T. A. , Centeno [ 199 ] C. Portet , G. , Yushin Y. Gogotsi , [ 194 ] A. Burke , [ 195 ] R. Dash , J. Chmiola , G. , Yushin Y. [ 196 ] Gogotsi , R. G. Lin , Laudisio , P. J. L. , Singer , Taberna J. Chmiola , [ 197 ] D. , Guay J. Y. Segalini , Gogotsi , P. B. Simon , Daffos , P. L. , Taberna Y. Gogotsi , P. Simon , [ 202 ] J. , Chmiola G. , Yushin Y. Gogotsi , C. Portet , P. Simon , [ 198 ] C. , Portet M. Á. Lillo-Ródenas , A. Linares-Solano , Y. Gogotsi , [ 190 ] E. Johansson , B. , Hjorvarsson T. , Ekström M. Jacob , [ 193 ] F. I. , Simjee P. H. Chou , [ 203 ] H. Shi , [ 204 ] J. , Chmiola C. Largeot , P. L. , Taberna P. [ 205 ] Simon , C. Y. Gogotsi , Largeot , C. , Portet [ 206 ] M. J. Arulepp , Chmiola , J. P.-L. Leis , , Taberna M. Y. , Latt Gogotsi , F. , Miller [ 208 ] K. S. K. , Gordeev , Rumma A. [ 209 ] V. , Vartanova S. E. K. , Gordeev Lust , A. [ 210 ] V. , Vartanova R. G. , Avarbz A. V. , Vartanova S. K. [ 211 ] , Gordeev S. K. S. , Gordeev A. [ 212 ] G. V. , Vartanova I. , Zjukov M. Kotina , V. M. , Lebedev A. G. Ilves , G. V. Patsekina , [ 191 ] A. Jerome , US [ 192 ] Patent 2005/0058875, P. Simon , A. Burke , [ 213 ] I. M. Kotina , V. M. , Lebedev A. G. Ilves , G. V. Patsekina , [ 207 ] E. Lust , A. Jänes , M. Arulepp , [ 214 ] H. S. Moon , J. M. Kim , Y. J. , Kim Korean Patent 2007–5625 www.MaterialsViews.com Adv. Funct. Mater. Funct. Adv.