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

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 H 2 evolution upon hydrolysis of sodium borohydride . The optimized Ni 2 Rh-, Ni 2 Pd- and Ni 2 Pt/Fe 3 O 4 nanocomposites exhibit outstanding catalytic performances on NaBH 4 hydrolysis with remarkable TOF values of 72.2, 69.2 and 46.1 L(H 2 )·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 ( E a ) of the hydrolysis of NaBH 4 is 54.95 kJ/mol with the catalyst Ni 2 Pt/Fe 3 O 4 . The Ni 2 Pt/Fe 3 O 4 has been successfully recycled 5 times and applied as an efficient “on–off” switch for on-demand H 2 evolution.