Sustainable hydrogen production by catalytic hydrolysis of alkaline sodium borohydride solution using recyclable Co–Co2B and Ni–Ni3B nanocomposites

In this article, we report Co–Co2B and Ni–Ni3B nanocomposites as catalyst for hydrogen generation from alkaline sodium borohydride. Kinetic studies of the hydrolysis of sodium borohydride with Co–Co2B and Ni–Ni3B nanocomposites reveal that the concentration of NaBH4 has no effect on the rate of hydrogen generation. Hydrolysis was found to be first order with respect to the concentration of catalyst. The catalytic activity of Co–Co2B was found to be much higher than that of Ni–Ni3B as inferred from the activation energies 35.245 KJ/mol and 55.810 kJ/mol, respectively. Co–Co2B nanocomposites were found to be more magnetic than Ni–Ni3B. These catalysts showed superior recyclability with almost the similar catalytic activities for several hydrolytic cycles supporting the principles of sustainability. Co–Co2B catalyst showed hydrogen generation rate of about 4300 mL/min/g which is comparable to most of the reported good catalysts till date.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The alkaline hydrolysis of sodium borohydride using Co–Co2B and Ni–Ni3B nanocomposites was carried out for hydrogen generation. ► Catalytic activity of Co–Co2B was found to be higher than that of Ni–Ni3B. ► Co–Co2B nanocomposites showed hydrogen generation rate of about 4300 mL/min/g, where as Ni–Ni3B showed 3400 mL/min/g. ► These nanocomposites could be used several times and can easily be separated magnetically.