Hydrogen generation from the hydrolysis of sodium borohydride solution over the supported Ni-Co-P/CNFs catalysts

The Ni-Co-P catalysts supported on carbon nanofibers (CNFs) were prepared via electroless deposition; the mass fractions of nickel, cobalt and phosphorus in Ni-Co-P layer are 13.30%, 82.25% and 4.45%, respectively, as determined by ICP-AES. The effects of catalyst amount, sodium borohydride and sodium hydroxide concentrations and reaction temperature on the rate of hydrogen generation in the hydrolysis of alkaline NaBH₄ solution were investigated. The results indicated that the rate of hydrogen generation is proportional to the used catalyst amount; a maximum hydrogen generation rate of 18.044 L/(g·min) is achieved at 45 ℃ by hydrolysis of 2.5% NaBH₄ solution containing 5% NaOH and 7.5 g/L Ni-Co-P/CNFs catalyst with a Ni-Co-P loading of 18.127%. Moreover, a kinetic study shows that the activation energy for the hydrolysis of alkaline NaBH₄ solution under those conditions is 51.57 kJ/mol.