DOCSLIB.ORG

April 16, 1974 C. N. WELCH 3,804,740 Ao

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
April 16, 1974 C. N. WELCH 3,804,740 Ao April 16, 1974 C. N. WELCH 3,804,740 ELECTRODES HAVING A DELAFOSSITE SURFACE Filed Feb. l., 1972 4 Sheet S-Sheet 1 ?oo W Ao 5o FC, 3.oOo 2.Soo d 2. oOo 500 3.OOO 2.5OO d. 2.ooo • Koo 2oo 3.ooo 2.5oo d 2.ooo 5oo 2oo 3.OOO 2.5OO d 2.OOO 5OO .2oo April 16, 1974 C. N. WELCH 3,804,740 ELECTRODES HAVING A DELAFOSSITE SURFACE Filed Feb. In l972 4 Sheets-Sheet 2 FF G G | April 16, 1974 C, N. WELCH 3,804,740 ELECTRODES HAWING ADELAFOSSITE SURFACE Filed Feb. l., 1972 4 Sheets-Sheet 3 - * « ŠMS —---- Pè.NO GS 5 G —==—È----==__ | N2 G April 16, 1974 C. N. WELCH- M 3,804,740 ELECTRODES HAWING A DELAFOSSITE SURFACE Filed Feb. 1, 1972 4 Sheets-Sheet 4 R | FFN -8 -SR 3,804,740 United States Patent Office Patented Apr. 16, 1974 1 2 3,804,740 N ELECTRO DES HAVING A DELAFOSSTE SURFACE DETAILED DESCRIPTION OF THE INVENTION Cletus N. Welch, Barberton, Ohio, assignor to Nora According to this invention, an electrode is provided International Company, Panama, Panama having a delafossite surface on an electroconductive sub Filed Feb. 1, 1972, Ser. No. 222,501 nt. Cl. B01k3/06; C01b 7/06, 11/26 strate. Delafossites are metal oxycompounds having the U.S. CI. 204-290 R . 3 Claims stoichiometric formula: ABO ABSTRACT OF THE DISCLOSURE where A is platinum, palladium, silver, or copper, and B is chromium, iron, cobalt, rhodium, aluminum, gado Electrodes useful for electrochemical reactions are dis 0 linium, scandium, indium, thallium, lead, ruthenium, and closed. Also disclosed are electrolytic cells utilizing such the lanthanides. B may also be any metal ion having a electrodes and the use of such electrodes in the conduct --3 formal valence state compatible with the delafossite of electrochemical reactions. The electrodes have dela structure. Delafossites also include non-stoichiometric fossite i surfaces on suitable electroconductive bases. compounds having the delafossite-type structure as de Delafossites are electroconductive oxycompounds of 5 fined herein. Delafossites have a unique crystallographic metals and include platinum cobalt delafossite (PtCoO), structure similar to that of the natural mineral delafossite palladium cobalt i delafossite (PdCoO), palladium (CuFeO2) with the slight differences in crystallographic chromium - delafossite (PdCrO2), palladium rhodium structure being due to slightly different ionic radii. delafossite (PdRhO2), palladium ruthenium delafossite Delafossites provide particularly satisfactory electrode (PdRuO2), palladium lead delafossite (PdPbO), the 20 materials because they combine high electrical conductiv palladium lanthanide delafossites, silver cobalt delafossite ity comparable to that of metals, with high resistance (AgCoO2), silver gadolinium delafosssite (AgGaO2), to chemical attack comparable to that of refractory metal silver scandium delafossite (AgScO2), silver indium dela oxides. For example, the bulk electrical conductivity of fossite - (AgInO2), silver thallium delafossite (AgT1O2), compressed powders of the platinum and palladium dela "copper i cobalt delafossite - (CuCoO2) and copper iron 25 fossites is on the order of about 108 to 104 (ohm-centi "delafossite (CuFeO2), includinig the mineral delafossite meters)--1. Such platinum and palladium delafossites are, (CuFeO). however, resistant to attack by strong acids such as aqua regia at 70° C. and by nascent chlorine. BACKGROUND 30 Delafossites are a family of oxides of two or more Numerous electrochemical reactions, such as the elec metals, the oxide having a rhombohedral structure with trolysis of . brines, hydrochloric acid, and sulfates, elec a hexagonal crystal habit similar to that of the mineral troplating, i electrowinning, electrolytic production of delafossite CuFeO2. Delafossites may further be char metal powders, electrolytic cleaning, electrolytic pickling, acterized in that their crystals have a space group of and the electrochemical generation of electric power, in 35 166, a Shoenflies group of Dadº, a Standard Full Symbol volve the use of non-consumable anodes. Previously, of graphite anodes have been used, especially in such proc esses as , the electrolysis of brines and the electrolysis R (R, bar 3, two over m) of hydrochloric acid. More recently, electrodes have been : developed for such processes utilizing a suitable electro 40 and an International Symbol of conductive base or substrate and an electrocatalytic coat ing thereon. Typically, such electrocatalytic coatings have Ram (R, bar 3, m) been the platinum group metals; e.g., platinum, osmium, iridium, ruthenium, i palladium, and rhodium, and their 45 Such oxides and their crystallography are particularly oxides. * • . " . described in the articles by W. J. Croft et al., Acta SUMMARY OF THE INVENTION Crystallogr., vol. 17, p. 313 (1964); W. Gessner, Z. Anorg. Allg. Chem., vol. 352, p. 145 (1966); H. Hahn It has now been found that a particularly satisfactory et al., Z. Anorg. Allg. Chem., vol. 279, p. 281 (1955); electrode for the conduct of electrochemical reactions W. Dannhauser et al., J. Amer. Chem. Soc., vol. 77, p. may be provided by the use of a delafossite surface on 50 896 (1955); H. Wiedersich et al., Mineral Mag., vol. 36, a suitable electroconductive substrate or base member. p. 643 (1968); A. Krause et al., Z. Anorg. Allg. Chem., Delafossites are oxides of high electrical conductivity vol. 228, p. 352 (1936); A. Pabst, Amer. Mineral, vol. 31, having the stoichiometric formula: p. 539 (1946); and A. H. Muir et al., J. Phys. Chem. Solids, vol. 28, p. 65; R. D. Shannon et al., “Chemistry ABO 55 of Noble Metal Oxides. I. Synthesis and Properties of A is platinum, palladium, silver, or copper. B is typical ABO Delafossite Compounds,” Inorganic Chemistry, vol. ly chromium, iron, cobalt, rhodium, aluminum, gadolini 10, p. 713 (1971); C. I. Prewitt et al., “Chemistry of um, scandium, indium, thallium, lead, ruthenium, and the Noble Metal Oxides. II. Crystal Structures of PtCoO, lanthanides. B may, however, be any metal ion having PdCoO2, CuFeO2, and AgFeO2” Inorganic Chemistry, a stable. --3 formal valence state compatible with the 60 vol. 10, p. 719 (1971); D. B. Rogers et al., “Chemistry delafossite structure. of Noble Metal Oxides. III. Electrical Transport Prop Delafossites also include i non-stoichiometric com erties and Crystal Chemistry of ABO Compound With pounds isostructural with the stoichiometric delafossites. the Delafossite Structure,” Inorganic Chemistry, vol. 10, A suitable electroconductive substrate is an electrocon p. 723 (1971); U.S. Pat. 3.498,931 to D. B. Rogers et ductive substrate that is substantially not attacked by the 65 al. for “Electrically conductive Oxides Containing Pal electrolyte. ladium and Their Preparation;” U.S. Pat. 3,514,414 to 3,804,740 5 6 These peaks of high intensity are caused by the X-rays For the more compact platinum group metal delafos being “reflected” from parallel planes in the crystal re site i crystals, a peak exists at about 1.76 to 1.81 ang inforcing each other. - The wave length of the X-rays, the stroms. This peak, at about 1.7655 for the platinum co spacing of the planes in the crystal, and the angle, e, are balt delafossite (PtCoO2), has an intensity of about 0.30. related by Bragg’s law. Bragg’s law is: For the palladium cobalt delafossite, the peak appearing at an interplanar distance of about 1.7616 angstroms has 2d sin E9:ssenM an intensity of about 0.30. For the slightly less compact where d is the distance between the planes of the crys palladium chromium delafossite (PdCrO2), the peak ap tal, n is an integer, M is the wave length of the X-rays, pears at about 1.8084 angstroms and has an intensity of and €9 is both the angle of incidence of the X-rays and the less than 0.05. angle of reflection of the X-rays. X-ray diffraction data are obtained from a diffractom TABLE 1 eter that is direct reading in 2e. The quantity (180° X-ray powder diffraction pattern for copper iron minus 269) is the angle between the incident ray and the 5 delafossite (CuFeO) reflected ray. d: - - . I/IIo Table I shows the X-ray diffraction pattern for the min 286 ------------------------------------ 35 eral delafossite (CuFeO). Particularly to be noted is the 2.58 ------------------------------------ 18 doublet at 2.58 and 2.508 angstroms and the peaks at 2.508 ----------------------------------- 100 2.238 and 1.658 angstroms, respectively. 2.238 ----------------------------------- 25 Certain generalities may be noted with respect to the 20 2.083 ----------------------------------- 6 powder X-ray diffraction patterns of the platinum group 1902 ----------------------------------- 9 metal delafossites. First to be noted is a particularly strong 1-6º8 ----------------------------------- 35 peak at a d value from about 5.9072 to 6.0229. Next to i 1.512 ----------------------------------- 40 be noted in FIGS. III through V, inclusive, is the existence 1-434 ----------------------------------- 20 of a strong doublet where the peaks are separated from 25 1336 ----------------------------------- 18 each other by from about 0.06 to about 0.07 angstrom 1295 ----------------------------------- 12 with the greater separation of peaks and greater differ 1253 ----------------------------------- 10 ences of intensities being for the platinum group metal 1.184 ----------------------------------- 6 delafossites having the larger unit crystal and the peaks 1.119 ----------------------------------- 10 being closer together and of more. nearly equal intensity 30 1.108 ----------------------------------- 6 for the platinum group metal delafossites having the more 1040 ----------------------------------- 18 compact unit crystal. For the platinum cobalt delafossite 0.984 ------- * 1 6 (PtCoO), the two peaks of the doublet are at 2.4260 and 0.965 ----------------------------------- 10 2.3609. angstroms. For the palladium cobalt delafossite (PdCoO), the two peaks of the doublet are at about 35 TABLE 2 2.4272 and 2.3616 angstroms, while for the palladium chromium delafossite the two peaks are at 2.5065 and X-ray powder diffraction pattern for platinum cobalt 2.4375 angstroms, and for the palladium rhodium dela M delafossite (PtCoO) fossite (PdRhO2) the two peaks are at about 2.5884 and d: M I/IIo 2.5141 angstroms.
Load more

Recommended publications
  • Thermoelectric and Transport Properties of Delafossite Cucro2
    Thermoelectric and transport properties of Delafossite CuCrO2:Mg thin films prepared by RF magnetron sputtering Inthuga Sinnarasa, Yohann Thimont, Lionel Presmanes, Antoine Barnabé, Philippe Tailhades To cite this version: Inthuga Sinnarasa, Yohann Thimont, Lionel Presmanes, Antoine Barnabé, Philippe Tailhades. Ther- moelectric and transport properties of Delafossite CuCrO2:Mg thin films prepared by RF magnetron sputtering. Nanomaterials, MDPI, 2017, 7 (7), pp.157. 10.3390/nano7070157. hal-01754780 HAL Id: hal-01754780 https://hal.archives-ouvertes.fr/hal-01754780 Submitted on 30 Mar 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Open Archive TOULOUSE Archive Ouverte ( OATAO ) OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible. This is a publisher’s version published in : http://oatao.univ-toulouse.fr/ Eprints ID : 19788 To link to this article : DOI:10.3390/nano7070157 URL : http://dx.doi.org/10.3390/nano7070157 To cite this version : Sinnarasa, Inthuga and Thimont, Yohann and Presmanes, Lionel and Tailhades, Philippe Thermoelectric and transport properties of Delafossite CuCrO2:Mg thin films prepared by RF magnetron sputtering . (2017) Nanomaterials, vol.
    [Show full text]
  • Delafossite Cu1+Fe3+O2
    1+ 3+ Delafossite Cu Fe O2 c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Hexagonal. Point Group: 32/m. Crystals tabular on {0001}, to 8 mm; also equant, bounded by {0001} and {1011}; as botryoidal crusts, spherulitic, powdery, massive. Twinning: On {0001}, as contact twins. Physical Properties: Cleavage: {1011}, imperfect. Tenacity: Brittle. Hardness = 5.5 D(meas.) = 5.41 D(calc.) = 5.52 Weakly magnetic. Optical Properties: Opaque. Color: Black; pale brownish rose in reflected light. Streak: Black. Luster: Metallic. Optical Class: Uniaxial. Pleochroism: Distinct; O = pale golden brown; E = rose-brown. Anisotropism: Strong. R1–R2: (400) 18.4–22.2, (420) 18.6–22.3, (440) 18.8–22.4, (460) 19.0–22.6, (480) 19.0–22.9, (500) 18.9–23.2, (520) 19.0–23.4, (540) 19.0–23.4, (560) 19.1–23.2, (580) 19.2–23.0, (600) 19.3–23.0, (620) 19.6–23.2, (640) 20.0–23.5, (660) 20.6–23.8, (680) 21.1–24.2, (700) 21.8–24.8 Cell Data: Space Group: R3m. a = 3.02–3.04 c = 17.10–17.12 Z = 3 X-ray Powder Pattern: Locality unknown. (ICDD 12-752). 2.508 (100), 1.512 (40), 2.86 (35), 1.658 (35), 2.238 (25), 1.434 (20), 2.58 (18) Chemistry: (1) (2) (3) Cu 42.14 41.32 41.97 Fe 33.56 37.26 36.89 O [19.74] [21.21] 21.14 rem. 3.52 0.21 Total [98.96] [100.00] 100.00 (1) Yekaterinburg, Russia; remnant is Al2O3.
    [Show full text]
  • Metal Oxide-Based Transparent Conducting Oxides Meagen Anne Gillispie Iowa State University
    Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 2006 Metal oxide-based transparent conducting oxides Meagen Anne Gillispie Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Materials Science and Engineering Commons Recommended Citation Gillispie, Meagen Anne, "Metal oxide-based transparent conducting oxides " (2006). Retrospective Theses and Dissertations. 1891. https://lib.dr.iastate.edu/rtd/1891 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. UMI Number: 3243848 UMI Microform 3243848 Copyright 2007 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, MI 48106-1346 Metal oxide-based transparent conducting oxides by Meagen Anne Gillispie A dissertation submitted to the graduate faculty in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Major: Materials Science and Engineering Program of Study Committee: David Cann, Co-major Professor Xiaoli Tan, Co-major Professor Mufit Akinc Vikram
    [Show full text]
  • Insights on the Stability and Cationic Nonstoichiometry of Cufeo2 Delafossite
    Open Archive Toulouse Archive Ouverte OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible This is an author’s version published in: http://oatao.univ-toulouse.fr/24270 Official URL: https://doi.org/10.1021/acs.inorgchem.9b00651 To cite this version: Pinto, Juliano Schorne and Cassayre, Laurent and Presmanes, Lionel and Barnabé, Antoine Insights on the Stability and Cationic Nonstoichiometry of CuFeO2 Delafossite. (2019) Inorganic Chemistry, 58 (9). 6431-6444. ISSN 0020-1669 Any correspondence concerning this service should be sent to the repository administrator: [email protected] Insights on the Stability and Cationic Nonstoichiometry of CuFeO2 Delafossite Juliano Schorne-Pinto,†,‡ Laurent Cassayre,† Lionel Presmanes,‡ and Antoine Barnabe*́,‡ † Laboratoire de Genié Chimique, Universitéde Toulouse, CNRS, Toulouse, France ‡ CIRIMAT, Universitéde Toulouse, CNRS, UniversitéPaul Sabatier, 118 Route de Narbonne, 31062 Toulouse, Cedex 9, France *S Supporting Information ABSTRACT: CuFeO2, the structure prototype of the delafossite family, has received renewed interest in recent years. Thermodynamic modeling and several experimental Cu−Fe−O system investigations did not focus specifically on the possible nonstoichiometry of this compound, which is, nevertheless, a very important optimization factor for its physicochemical properties. In this work, through a complete set of analytical and thermostructural techniques from 50 to 1100 °C, a fine reinvestigation of some specific regions of the Cu−Fe−O phase diagram under air was carried out to clarify discrepancies concerning the delafossite CuFeO2 stability region as well as the eutectic composition and temperature for the reaction L = ff ’ CuFeO2 +Cu2O.
    [Show full text]
  • Interfacial Stabilization for Epitaxial Cucro2 Delafossites
    www.nature.com/scientificreports OPEN Interfacial stabilization for epitaxial CuCrO2 delafossites Jong Mok Ok1,3, Sangmoon Yoon1,3, Andrew R. Lupini2, Panchapakesan Ganesh2, Matthew F. Chisholm2 & Ho Nyung Lee1* ABO2 delafossites are fascinating materials that exhibit a wide range of physical properties, including giant Rashba spin splitting and anomalous Hall efects, because of their characteristic layered structures composed of noble metal A and strongly correlated BO2 sublayers. However, thin flm synthesis is known to be extremely challenging owing to their low symmetry rhombohedral structures, which limit the selection of substrates for thin flm epitaxy. Hexagonal lattices, such as those provided by Al2O3(0001) and (111) oriented cubic perovskites, are promising candidates for epitaxy of delafossites. However, the formation of twin domains and impurity phases is hard to suppress, and the nucleation and growth mechanisms thereon have not been studied for the growth of epitaxial delafossites. In this study, we report the epitaxial stabilization of a new interfacial phase formed during pulsed-laser epitaxy of (0001)-oriented CuCrO2 epitaxial thin flms on Al2O3 substrates. Through a combined study using scanning transmission electron microscopy/electron- energy loss spectroscopy and density functional theory calculations, we report that the nucleation of a thermodynamically stable, atomically thick CuCr1−xAlxO2 interfacial layer is the critical element for the epitaxy of CuCrO2 delafossites on Al2O3 substrates. This fnding provides key insights into the thermodynamic mechanism for the nucleation of intermixing-induced bufer layers that can be used for the growth of other noble-metal-based delafossites, which are known to be challenging due to the difculty in initial nucleation.
    [Show full text]
  • Transparent Conducting Oxides—An Up-To-Date Overview
    Materials 2012, 5, 661-683; doi:10.3390/ma5040661 OPEN ACCESS materials ISSN 1996-1944 www.mdpi.com/journal/materials Article Transparent Conducting Oxides—An Up-To-Date Overview Andreas Stadler University of Salzburg, Hellbrunner Str. 34, Salzburg A-5020, Austria; E-Mail: [email protected]; Tel.: +43-662-8044-2111; Fax: +43-662-8044-622 Received: 20 January 2012; in revised form: 9 March 2012 / Accepted: 28 March 2012 / Published: 19 April 2012 Abstract: Transparent conducting oxides (TCOs) are electrical conductive materials with comparably low absorption of electromagnetic waves within the visible region of the spectrum. They are usually prepared with thin film technologies and used in opto-electrical apparatus such as solar cells, displays, opto-electrical interfaces and circuitries. Here, based on a modern database-system, aspects of up-to-date material selections and applications for transparent conducting oxides are sketched, and references for detailed information are given. As n-type TCOs are of special importance for thin film solar cell production, indium-tin oxide (ITO) and the reasonably priced aluminum-doped zinc oxide (ZnO:Al), are discussed with view on preparation, characterization and special occurrences. For completion, the recently frequently mentioned typical p-type delafossite TCOs are described as well, providing a variety of references, as a detailed discussion is not reasonable within an overview publication. Keywords: transparent conducting oxide; oxide; TCO; ITO; ZnO:Al; delafossite 1. Introduction Transparent conducting oxides (TCOs) are electrical conductive materials with a comparably low absorption of light. They are usually prepared with thin film technologies and used in opto-electrical devices such as solar cells, displays, opto-electrical interfaces and circuitries.
    [Show full text]
  • Synthesis and Characterisation of Delafossite Cufeo for Solar Energy
    UPTEC Q 16006 Examensarbete 30 hp Juni 2016 Synthesis and characterisation of delafossite CuFeO2 for solar energy applications Axel Forslund Abstract Synthesis and characterisation of delafossite CuFeO2 for solar energy applications Axel Forslund Teknisk- naturvetenskaplig fakultet UTH-enheten Delafossite CuFeO2 is an intrinsic p-type semiconductor with a band gap around 1.5 eV. Further, it is composed of relatively abundant, nontoxic Besöksadress: elements, and therefor have potential to be an attractive material for solar Ångströmlaboratoriet Lägerhyddsvägen 1 energy harvesting.This Work examines three routes to synthesise this material. Hus 4, Plan 0 The first includes a sol-gel Deposition and then relies on solid state reaction above 650 Degrees Celsius in inert gas atmosphere. In this Work, no Delafossite Postadress: is obtained with this methoD.The second methoD is a hyDrothermal route to Box 536 751 21 Uppsala maKe particles under hyDrostatic pressure in an autoclave. Delafossite is obtained mixed with other phases.The thirD route includes aqueous Telefon: precipitation similar to the second route, but a temperature of 70 Degrees 018 – 471 30 03 Celsius and ambient pressure is sufficient to proDuce a pure Delafossite particle Telefax: phase. It provides a robust and simple way to maKe Delafossite CuFeO2 018 – 471 30 00 particles.The resulting particles are Deposited and compressed on glass into thin films.The films have a band gap slightly below 1.5 eV and show some Hemsida: photoactivity in electrochemical measurements. http://www.teknat.uu.se/student Handledare: Gerrit Boschloo Ämnesgranskare: Tomas Edvinsson Examinator: Åsa Kassman Rudolphi ISSN: 1401-5773, UPTEC Q 16006 Syntes och karakterisering av CuFeO2-delafossit för solenergitillämpningar Axel Forslund Som en del i att minska den mänskliga påverkan på klimatet måste användningen av fossila bränslen reduceras.
    [Show full text]
  • DELAFOSSITE from KIMBERLY, NEVADA Ausrrwf
    r02 rH E A M ERICAN M I N ERAINGIST heavy solution for separations of hydrous silicates readily decom- posed by acids. Possibly other analyses of zeolites exhibit irregu- larities due to similar substitutions. DELAFOSSITE FROM KIMBERLY, NEVADA AusrrwF. Rocnns,StanJoril Uni,aersi,ty Of the numerous copper minerals, one of the rarest and most interesting is delafossite,a cuprous metaferrite, with the formula, CuFeOzor CurO.FezOr. Delafossitewas first describedfrom the region of Ekaterinburg, Siberia, by Friedel in 1873.r No further mention of the mineral was made until 1913, when the writer2 called attention to its occurrenceat Bisbee, Arizona, and was able to establish it as a valid mineral species. Thq object of this note is to place on record the discovery of delafossite at a second American locality. A specimen of the mineral in question was sent to my colleague, professor W. F. Dietrich, by Mr. M. L. Crandall, Chief Engineer of the Con- solidated Coppermines Company. The specimenwas found on the 1200 ft. level of the Alpha mine (formerly called the Giroux) at Kimberly, Nevada. According to Mr. Crandall, ,,It was found in a body of clay containing some oxidized copper ore, occurring in oxidized jasperoid, near its contact with limestone.', Dr,scnrprrox oF THE Dcralossrra: The Kimberly delafossite is a black metallic mineral and occurs in spherical aggregatesfrom 1 to 3 mm. in diameter which are disseminated through a white to pale gray clay. (The clay is probably halloysite, the amorphous equivalent of crystalline kaolinite, as it is optically isotropic and has an index of refraction of 1 .543 + .003.) The spherulitic aggre- gates have a fairly well defined radial structure and hence may be called spherulites.
    [Show full text]
  • Sample Journal Article Title Page Co-Authored Preprint
    BNL-114168-2017-JA Electrochemical (de)lithiation of silver ferrite and composites: Mechanistic insights from ex-situ, in-situ, and operando x-ray techniques J. L. Durham, D. C. Bock Submitted to Physical Chemistry Chemical Physics August 2, 2017 Energy and Photon Sciences Directorate Brookhaven National Laboratory U.S. Department of Energy USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22) Notice: This manuscript has been co-authored by employees of Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy. The publisher by accepting the manuscript for publication acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or any third party’s use or the results of such use of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof or its contractors or subcontractors.
    [Show full text]
  • Structural and Magnetic Properties of Substituted Delafossite-Type Oxides Cucr1 − Xscxo2
    World Journal of Condensed Matter Physics, 2013, 3, 1-8 1 doi:10.4236/wjcmp.2013.31001 Published Online February 2013 (http://www.scirp.org/journal/wjcmp) Structural and Magnetic Properties of Substituted Delafossite-Type Oxides CuCr1 − xScxO2 Taieb Elkhouni1, Mongi Amami1,2*, Pierre Strobel3, Abdelhamid Ben Salah1 1Laboratory of Material Sciences and Environnement, Faculty of Science of Sfax, Sfax, Tunisia; 2Unit of Material chemistry Re- search, University of Tunis Elmanar, Tunis, Tunisie; 3Neel Institute, CNRS, Grenoble, France. Email: *[email protected] Received July 28th, 2012; revised September 29th, 2012; accepted October 11th, 2012 ABSTRACT This work describes the scandium doping effect on the structural and magnetic properties of delafossite-type oxi- des CuCr1 − xScxO2. The lattice parameters were found to vary according to Vegard’s low. A reflection broadening is observed, that is ascribed to local lattice distortion due to the ionic radius difference between Cr3+ and the non-mag- netic dopants. Magnetic susceptibility measurements show that the dominant interactions are antiferromagnetic (AFM) but that doping induces significant changes. The coupling between the local spins at the Cr sites and do- ped metal transition may enhance spin fluctuations at the Cr sites, which break the residual magnetic degeneracy as fluctuation-induced symmetry breaking in a highly magnetic degenerate ground state manifold of some frustrated sys- tems. Keywords: Delafossite; XRD; Raman Spectroscopy; Magnetism 1. Introduction plications as transparent conductors [5]. Copper-scandium oxide (CSO) is a p-type transparent The family of layered oxides generally referred to as Cu+-based oxide with a delafossite structure. Holes in delafossites derive their name from the mineral CuFeO 2 CSO are introduced by substituting divalent species for [1], with which their crystal structures are isotypic.
    [Show full text]
  • Delafossite» Observed for the First Time in Turkey
    A NEW MINERAL «DELAFOSSITE» OBSERVED FOR THE FIRST TIME IN TURKEY Ahmet ÇAĞATAY and Oğuz ARDA Mineral Research and Exploration Institute of Turkey SUMMARY. — In association with some secondary minerals such as limonite, malachite, native copper, cuprite, tenorite and covelline; delafossite is found along the fractures of phyllitic rocks within the oxidized zone in the Malatya-Pötürge area. A detailed mineralogic study has been carried out about delafossite since it is observed first time in Turkey. INTRODUCTION A rock sample showing phyllite characteristics and containing a rarely encountered mineral delafossite is collected and brought for identification by Aykut Tümer (from the Geo- physical Department of the M.T.A.) from a locality to the south of Kılışık, near Çanakçı vil- lage, north of Pötürge (Malatya Province). Delafossite is found within the cracks of this phyllitic rock (Microphoto I), which underwent strong cataclastic deformation and silicification. The location where the sample is taken is shown in Figure I. Delafossite, which occurs in association with other secondary minerals, is studied under the ore microscope of Leitz-made Oftholux II Pol-Bk. In addition, reflection and Vickers mi- crohardness tests are carried out on the delafossite with the aid of a Vickers microscope. The reflection measurements are taken by using a Wolfram Carbide Standard of Zeiss-made, Stan- dard number: 474253, no. 061. The X-ray diffraction studies on delafossite are carried out by the aid of a Phillips X-ray diffractometer. DELAFOSSITE Chemical formula.— Ramdohr (I960) gives the chemical composition of delafossite as CuFeO2. Buist, Gadalla and White (1966), who carried out an experimental investigation on the Cu-Fe-O system, found that the natural delafossite resembles a synthetic phase of this sys- tem in 3Cu2O.Fe3O4 composition.
    [Show full text]
  • Cu-Based Transparent Conducting Oxides Based on the Delafossite Structure
    Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1-1-2003 Cu-based transparent conducting oxides based on the delafossite structure Robert Bruce Gall Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Recommended Citation Gall, Robert Bruce, "Cu-based transparent conducting oxides based on the delafossite structure" (2003). Retrospective Theses and Dissertations. 19966. https://lib.dr.iastate.edu/rtd/19966 This Thesis is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Cu-based transparent conducting oxides based on the Delafossite structure by Robert Bruce Gall A dissertation submitted to the graduate faculty in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Major: Materials Science and Engineering Program of Study Committee: David P. Cann, Major Professor Steve Martin Gordon Miller Iowa State University Ames, Iowa 2003 11 Graduate College Iowa State University This is to certify that the master's thesis of Robert Bruce Gall has met the thesis requirements for Iowa State University Signatures have been redacted for privacy TABLE OF CONTENTS CHAPTER 1. INTRODUCTION i 1.1 Background 1 1.1.1 Transparent Conducting Oxides
    [Show full text]