▎ 摘　　要

A cobalt (Co)/graphene sheets (GRs) composite was synthesized via a one-pot chemical method. The composite shows high saturation magnetizations (M-s), which leads it to be conveniently separated from aqueous solution by an external magnetic field. Compared to the pure Co and some references, the catalytic activity of the as-obtained composite was significantly enhanced for the generation of H-2 gas by hydrolysis of NaBH4 solution. Effects of NaBH4 initial concentration, the composite and reaction temperature on the H-2 generation rate were investigated. The H-2 generation rate is independent with the initial NaBH4 concentration, increased with the reaction temperature increasing. The composite can be continuously used several times with about the same catalytic activity.