Selective deposition of nanostructured ruthenium oxide using Tobacco mosaic virus for micro-supercapacitors in solid Nafion electrolyte

Abstract

h i g h l i g h t sA method of selective patterning of RuO 2 on microelectrodes is described. The microelectrodes consist of titanium nitride with Au and Ni functional areas. Micro-supercapacitors in solid Nafion electrolyte are tested. Electrode capacitance has been measured as high as 203 mF cm À2 . The presence of Tobacco mosaic virus nanotemplate improves rate capability. a b s t r a c tA three-dimensional micro-supercapacitor has been developed using a novel bottom-up assembly method combining genetically modified Tobacco mosaic virus (TMV-1Cys), photolithographically defined micropillars and selective deposition of ruthenium oxide on multi-metallic microelectrodes. The threedimensional microelectrodes consist of a titanium nitride current collector with two functionalized areas: (1) gold coating on the active electrode area promotes TMV-1Cys adhesion, and (2) sacrificial nickel pads dissolve in ruthenium tetroxide plating solution to produce ruthenium oxide on all electrically connected areas. The microfabricated electrodes are arranged in an interdigitated pattern, and the capacitance per electrode has been measured as high as 203 mF cm À2 with solid Nafion electrolyte. The process integration of bio-templated ruthenium oxide with microfabricated electrodes and solid electrolyte is an important advance towards the energy storage needs of mass produced self-sufficient microdevices.

Recent Progress in Ruthenium Oxide‐Based Composites for Supercapacitor Applications

“…Deploy of solid electrolyte besides improving the device stability, also significantly relaxes the packaging complexity. [265] The usage of ionic liquids in EDLCs has been extensively studied in the recent years. [266][267] Employing various protic ionic liquids with varying conductivities, viscosities, thermal as well as electrochemical features, exhibited specific capacitance range values close to the reference of 40-45 F g À 1 for RuO 2 as obtained in 0.5 M H 2 SO 4 within the limits of experimental inaccuracy.…”

Virus-directed formation of electrocatalytically active nanoparticle-based Co3O4 tubes

“…47 Key to their performance as templates, the surfaces of TMV particles are patterned with chemically-distinct nanoscale domains that can specifically bind different materials and ions, [48][49][50] and thus mediate the preparation of a range of bio-inorganic hybrid materials based on metals such as Pt, 51 Co, 52 and Ni 53 and metal oxides including ZnO, 54,55 SiO2, 56 TiO2, 57 and RuO2. 58 While common templating strategies are based on coating individual virus particles or viruses immobilized on substrates with inorganic materials, our studies on TMV-mediated deposition of basic cobalt carbonates take these experiments one stage further, and exploit the ability of Co (II) ions not only to bind to TMV particles but to drive their ordered association in solution. These Co 2+ / TMV complexes are then used to generate hierarchically-structured rod-shaped and tubular Co(CO3)x(OH)y/ virus composites, whose conversion into spinel-type cobalt oxide by annealing can be achieved with conservation of morphology.…”

On‐Chip Microsupercapacitors: From Material to Fabrication

“…[113] RuO 2 can also be coated on other structures by ALD and nanotemplate electrodeposition. [73,114] Considering the micro/nano-length scales of the produced electrodes and the excellent areal capacitance up to hundred microfarads, these results suggest that the performance of MSCs will be further enhanced by reducing the resolution of the film. However, high cost and incompatible fabrication of RuO 2 often hamper its applications widely.…”