Nanostructured cobalt-phosphorous catalysts for hydrogen generation from hydrolysis of sodium borohydride solution

Nanostructured Co-P/Cu sheet catalysts were successfully synthesized by electroless plating method. The effects of the deposition temperature on microstructures of Co-P catalysts and their catalytic properties for hydrogen generation from NaBH4 solution were systematically investigated. By tuning the deposition temperature, the morphology of the surface of the Co-P catalysts changed significantly, such as nanoplatelets, nanospheres, pores and nanoclews. When the deposition temperature was 50 °C, the as-prepared Co-P catalyst with novel hierarchical architectures exhibited enhanced catalytic performance during the hydrolysis of NaBH4. The hydrogen release rate of 2275.1 mL min−1 g−1 was achieved. This enhanced activity might be due to the novel hierarchical architectures, small size of Co phase precipitated from the amorphous Co-P phase, or the high surface roughness, which provided many defects (such as angle, step, or edge etc.) and formed more active sites on the catalyst surface. Meanwhile, the lower apparent activation energy of 27.9 kJ mol−1 was calculated. Furthermore, the Co-P catalyst retained about 67% catalytic activity of its first activity after 5 cycles, which illustrated that the hydrogen release rate decreased gradually. The reason might be due to the reduction of in the amount of P and Co on the catalytic surface analyzed by XPS.