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Direct Methanol Fuel Cell (DMFC) is a promising power source for continuous generation of energy without evolution of any toxic by-products and greenhouse gases. Pt-Ru has been the accepted gold standard anode electro-catalyst for DMFC, but significant advances are required to enhance its performance and stability. A complexed sol-gel (CSG) approach has been used to develop nanostructured powder materials. Herein we report a novel CSG process to synthesize nanoparticulate high specific surface area (HSA), completely unsupported Pt(Ru) based electro-catalyst exhibiting three fold higher electrochemically active surface area (ECSA) and ultra high electrochemical performance compared to commercially available Johnson Matthey Pt-Ru black catalyst, the currently accepted gold standard. Furthermore, in identical single full cell DMFC configuration tests for methanol oxidation, current and power densities ~40% higher than that displayed by Johnson Matthey catalyst is achieved. [ABSTRACT FROM AUTHOR]

Nanostructured powder catalysts comprising solid solutions of F doped SnO2 and IrO2 of different compositions were synthesized by a simple two step approach. High surface area SnO2:F was prepared initially using CTAB as a surfactant. (Ir,Sn)O2:F was then synthesized by forming a solid state solution with IrCl4 and SnO2:F followed by heat-treatment in air at 400°C. The catalyst was then coated onto a porous Ti foil and has been studied as a promising anode electro-catalyst for oxygen evolution reaction (OER) in PEM based water electrolysis. The optimal composition of (Ir0.3Sn0.7)O2:10 wt% F displayed electrochemical activity comparable to the commercially available pure IrO2 demonstrating ~70 mol% reduction in noble metal content. The electrochemical stability tests also showed that (Ir,Sn)O2:F solid solution exhibits much better durability compared to commercial IrO2, the standard (OER) catalyst. [ABSTRACT FROM AUTHOR]

Nanocrystalline vanadium nitride (VN) has been synthesized using a simple two-step procedure involving mechano-chemical reaction of V2O3 and Li3N mixture induced by high energy mechanical milling (HEMM) followed by washing in water. The crystalline VN thus synthesized has been analyzed as a supercapacitor material in aqueous media. The electrochemical mechanism and material properties influencing the supercapacitor behavior of VN have been explored. The surface properties of the nanocrystalline VN have also been studied using X-ray photo-electron spectroscopy (XPS) and correlated to the electrochemical response. Stable capacitances of upto 60 F/g are reported here for nanocrystalline VN generated using the high energy mechano-chemical reaction method. Cycling induced degradation of capacitance has also been studied and the possible degradation mechanisms have been discussed. [ABSTRACT FROM AUTHOR]