Review SUPPLEMENTARY MATERIAL Metal Nanotube/Nanowire-Based Unsupported Network Electrocatalysts Falk Muench1,* 1 Technische Universität Darmstadt, Department of Materials and Earth Sciences, 64287 Darmstadt, Germany; [email protected] * Correspondence: [email protected]; Tel.: +49-6151-1621994 Table S1. Summary of the nano-network examples discussed in section 2.1 (2D nano-networks, preparation from colloidal building blocks). Ref. Nanomaterial Fabrication Application colloidal Ag nanowire synthesis; drop [14] merged Ag nanowire film transparent conductor casting + rolling; electroless plating colloidal Ag nanowire synthesis; surface-enhanced [30] aligned Ag nanowire film interfacial assembly Raman spectroscopy commercial Ag nanowires; spray [36] merged Ag nanowire film transparent conductor coating; halide welding colloidal Ag nanowire synthesis; drop [37] merged Ag nanowire film transparent conductor casting; plasmonic welding colloidal Ag nanowire synthesis; drop [38] merged Ag nanowire film casting; heat treatment / mechanical transparent conductor pressing commercial Ag nanowires; membrane transparent, flexible [39] Ag nanowire film filtration; membrane collapse H2O2 sensor electrode colloidal Cu nanowire synthesis; graphene-coated Cu membrane filtration + nanowire transparent electrode for [40] nanowire film transfer; chemical vapor deposition of hydrogen evolution carbon colloidal Cu nanowire synthesis; Cu-Pt core-shell nanowire nanowire ink preparation + rolling + transparent electrode for [41] film pressing; plasma cleaning; Pt hydrogen evolution electrodeposition colloidal Pd nano-sheets; chemical [42] colloidal Pd nano-mesh ethanol electrooxidation etching www.mdpi.com/journal/catalysts 2 of 7 Table S2. Summary of the nano-network examples discussed in section 2.2 (2D nano-networks, template-assisted deposition). Ref. Nanomaterial Fabrication Application electrospinning of polymer-SnCl2 [45] Cu / Ag nanofiber film nanofibers; fiber seeding in AgNO3 transparent conductor solution; electroless Cu / Ag plating anodized nanoporous Al substrate; [46] Pd nanowire film resistive H2 sensor Pd sputtering electrospinning of polymer [47] metal nanotrough film nanofibers; thermal / electron beam transparent conductor evaporation of various metals catalytic conductive electrospinning of polymer-H2PtCl6 [48] Pt nanowire film transparent solar cell nanofibers; heat treatment electrodes grain boundary lithography + Au transparent stretchable [49] Au nanowire mesh electron beam evaporation conductors ordered, optionally crossed replication of periodic Si master metallic photonic [50] Au nanowire layers grating with polymer; Au sputtering crystals 3 of 7 Table S3. Summary of the nano-network examples discussed in section 3.1 (3D nano-networks, preparation from individual 1D nanostructures). Ref. Nanomaterial Fabrication Application colloidal Cu nanowire synthesis; drop electrochemical glucose [51] Cu nanowire layer casting; Nafion binder addition detection colloidal Ag nanowire synthesis; drop Prussian blue modified Ag casting on electrode with dithiol electrochemical H2O2 [52] nanowire layer linker; Prussian blue aerosol and glucose detection deposition electrochemical CO2 colloidal Ag nanowire synthesis; drop [53] Ag nanowire layer reduction / hydrogen casting with Nafion binder evolution colloidal Ag nanowire synthesis; methanol [55] Pt nanotube layer galvanic exchange; drop casting; electrooxidation Nafion binder addition colloidal Ag nanowire synthesis; oxygen reduction [56] Pd-Pt nanotube layer galvanic Pd/Pt exchange; drop reaction casting; Nafion binder addition colloidal Cu nanowire synthesis; oxygen reduction [57] Pt-Cu nanotube layer galvanic Pt exchange; acid treatment; reaction drop casting; Nafion binder addition electrochemical colloidal Ag nanowire synthesis; oxidation of various [58] Pd / Au nanotube layer galvanic exchange; drop casting alcohols, oxygen reduction reaction colloidal Te nanowire synthesis; methanol [59] Pt-Au nanotube layer galvanic Au/Pt exchange; drop electrooxidation casting; Nadion binder addition colloidal Cu nanowire synthesis; Pt-Ru nanotubes / Pt-Ru- methanol [60] complete / partial galvanic Pt/Ru Cu nanowire layer electrooxidation exchange; drop casting template-assisted electroless synthesis double-walled Ag-Pt of Ag nanotubes; template methanol [61] nanotube layer dissolution; galvanic Pt exchange; electrooxidation variable Ag etching; drop casting template-assisted electroless Pt methanol [64] Pt / Pt-Ru nanotube layer plating; optional Ru deposition; electrooxidation template dissolution on electrode template-assisted electroless Rh layer built from micro- / electrochemical H2O2 [65] plating; template dissolution; drop mesoporous Rh nanotubes detection casting template-assisted electroless Au layer built from solid / electrochemical H2O2 [66] plating; template dissolution on porous Au nanotubes detection electrode template-assisted chemical vapor deposition of Pt and hydrous Ru methanol [68] Pt-Ru nanotube layer oxide; optional annealing; template electrooxidation dissolution; drop casting template-assisted multi metal oxygen reduction electrodeposition from DMSO reaction / [72] Pd-Au-Cu nanotube layer electrolyte; template dissolution; drop electrochemical H2O2 casting with Nafion binder reduction commercial Ni nanowires; galvanic Pt [74] Pt-Ni nanowire layer H2 / O2 fuel cell exchange; optional Ni leaching; ink 4 of 7 preparation with Nafion; spray coating on fuel cell membrane commercial Ag nanowires; nanowire suspension in H2O with surfactant; [75] 3D Ag nanowire aerogel - gelation via solvent evaporation; supercritical drying colloidal Cu nanowire synthesis; [76] 3D Cu nanowire aerogel gelation with increasing nanowire fluid wicking density; freeze-drying template-assisted Pd nanowire electrodeposition; template removal; [77] 3D Pd nanowire aerogel H2 storage nanowire suspension in H2O; shock freezing; freeze-drying 5 of 7 Table S4. Summary of the nano-network examples discussed in section 3.2 (3D nano-networks, template-assisted deposition). Ref. Nanomaterial Fabrication Application Pt electrodeposition in ion-track interconnected Pt methanol [2] etched polymer template; template nanowires electrooxidation dissolution electroless plating of various metals interconnected metal electrochemical H2O2 [13] onto ion-track etched polymer nanotube networks detection templates; template dissolution electroless Cu plating of commercial Cu / Cu-Ni / Cu oxide ion-track etched templates with electrochemical glucose [63] (core-shell) nanotube widened pores; template dissolution; detection networks optional derivatization interconnected Ni Ni electrodeposition in alumina [84] - nanowires template; template dissolution Ni-Sn electrodeposition in alumina parallel / interconnected lithium ion battery [85] template variants; template Ni-Sn nanowires anode dissolution Ni electrodeposition in alumina parallel / interconnected Ni [86] template variants; template - nanowires dissolution hierarchical, electroless plating / electrodeposition interconnected metal combined with hierarchically porous electrochemical H2O2 [90] microwire / nanowire / ion-track etched templates; template detection nanotube networks removal electroless Ni / Ni-B plating of ion- interconnected Ni / Ni-B [92] track etched PET template with ethanol electrooxidation nanotube arrays planar voids; template dissolution electroless Pt plating of ion-track interconnected porous Pt methanol [98] etched polymer template; template nanotubes electrooxidation dissolution interconnected Ni / Ni-NiO Ni electrodeposition in ion-track [103] / NiO (core-shell) etched polymer template; template lithium ion microbattery nanowires dissolution; thermal oxidation Ni electrodeposition in ion-track interconnected Ni magnetism / microwave [104] etched polymer template; template nanowires absorption studies dissolution Ni / Ni-Co / Co electrodeposition in interconnected Ni / NiCo / [105] ion-track etched polymer template; magnetism studies Co nanowires template dissolution Ni-Fe / Co electrodeposition in ion- interconnected Ni-Fe / Co [106] track etched polymer template; magnetism studies nanowires template dissolution core-shell-segregated Ni-Cu interconnected Ni electrodeposition in ion-track etched [107] magnetism studies nanotubes polymer template; selective Cu dissolution; template dissolution electroless Pt plating of commercial interconnected Pt methanol [111] ion-track etched polymer template; nanotubes electrooxidation template dissolution Cu electrodeposition in commercial interconnected Cu [112] ion-track etched polymer template; heat transfer nanowires template dissolution 6 of 7 live monitoring of a fragmented network of electroless Au plating of commercial catalytic reaction [113] interconnected Au ion-track etched polymer template; (nitrophenol reduction) nanowires template dissolution; drop casting via surface enhanced Raman spectroscopy nanoelectrode ensemble fragmented network of electroless Au plating of commercial (performed with [114] interconnected Au ion-track etched polymer template; template-embedded / - nanotubes template dissolution; drop casting stabilized nanostructures) electrodeposition of Pt-Cu in commercial ion-track etched interconnected porous Pt electrochemical H2O2 / [116] template; termplate dissolution; Cu nanowires glucose detection dealloying; immobilization of glucose oxidase 7 of 7 Table S5. Summary of the nano-network examples discussed in section 3.3 (3D nano-networks, nanofiber networks