▎ 摘　　要

Three-dimensional Ni@graphene (NG) was prepared for the first time at a low temperature by a one-step facile calcination method. The obtained NG showed a high specific capacitance of 765 F g(-1) at a current density of 1 A g(-1) and only 5% loss of the initial specific capacitance after 3000 charge-discharge cycles.