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Abstract: Hydrolysis of sodium borohydride NaBH4 is a promising method for on-board hydrogen supply for fuel cells. In this study, the hydrolysis reaction was studied by starting with solid NaBH4 rather than aqueous borohydride solutions, and adding less amount of water in an attempt to explore the maximum hydrogen generation capacity. It was found that hydrogen could be liberated at very high rates and over than 90% conversion rates were achieved when the mole ratio of water to sodium borohydride was not less than 4:1. The final hydrogen generation capacity was achieved as high as 6.7wt%. Materials such as CoCl2 or cobalt powder were found to be effective as the catalysts for the hydrolysis reaction at such reaction conditions. A large heat effect due to the exothermic reaction and a low melting point of NaBO2·4H2O led to the acceleration of hydrogen generation at the latter part of the hydrolysis process. It is thus promising to utilize these reaction conditions to achieve high hydrogen generation capacity by proper system design. [Copyright &y& Elsevier]

Abstract: A direct hydrazine fuel cell using H2O2 as the oxidizer has been developed. The N2H4/H2O2 fuel cell is assembled by using Ni–Pt/C composite catalyst as the anode catalyst, Au/C as the cathode catalyst, and Nafion membrane as the electrolyte. Both anolyte and catholyte show significant influences on cell voltage and cell performance. The open-circuit voltage of the N2H4/H2O2 fuel cell reaches up to 1.75V when using alkaline N2H4 solution as the anolyte and acidic H2O2 solution as the catholyte. A maximum power density of 1.02Wcm−2 has been achieved at operation temperature of 80°C. The number of electrons exchanged in the H2O2 reduction reaction on Au/C catalyst is 2. [Copyright &y& Elsevier]