This paper investigates the effect of an electroplated Co-P catalyst on hydrogen generation kinetics from hydrolysis of NH3BH3. The Co-P catalyst is composed of an amorphous Co-P phase and Co nanoparticles. An increase in NH3BH3 concentration caused the hydrogen generation rate to increase dramatically. The Co-P catalyst shows a large hydrogen generation rate for 2 wt% NH3BH3 solution at 30 degrees C. This is 1.8 times higher than that of the Pt/C catalysts and 6 times higher than that of Ru catalysts. The activation energy for hydrolysis of NH3BH3 by the Co-P catalyst is calculated to be 22 kJ/mol, which is close to that of noble metal-based catalysts. (C) 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.