On-demand hydrogen evolution upon magnetic composite-nanocatalyzed sodium borohydride hydrolysis

Abstract Fast and convenient hydrogen evolution under ambient condition from stable hydrogen-rich materials is highly awaited. Herein, a series of magnetic nanocomposites are reported as robust catalysts for promoting H2 evolution upon hydrolysis of sodium borohydride. The optimized Ni2Rh-, Ni2Pd- and Ni2Pt/Fe3O4 nanocomposites exhibit outstanding catalytic performances on NaBH4 hydrolysis with remarkable TOF values of 72.2, 69.2 and 46.1 L(H2)·g.cat−1·min−1, respectively, due to sharp volcano-type synergetic effect between Ni and the noble metal. Based on the Arrhenius equation, the activation energy (Ea) of the hydrolysis of NaBH4 is 54.95 kJ/mol with the catalyst Ni2Pt/Fe3O4. The Ni2Pt/Fe3O4 has been successfully recycled 5 times and applied as an efficient “on–off” switch for on-demand H2 evolution.