Electrodeposition of Ni(OH)2/Ni/graphene composites under supergravity field for supercapacitor application

A method of electrodeposition under supergravity field is proposed to prepare Ni(OH)2/Ni/graphene composites. Particles composed of Ni(OH)2 and Ni are covered by a thin graphene coating. The Ni(OH)2/Ni/graphene composite is evaluated as electrodes for supercapacitors, which shows that the specific capacitance of Ni(OH)2/Ni/graphene is 2609 F g−1 at a current density of 0.5 A g−1 in 6 M KOH solution. In addition, it could still reach 1020 F g−1 at a current density of 4 A g−1. On the other hand, electrodeposition under supergravity field could decrease concentration polarization and promote ion diffusion, which is a promising strategy for the fabrication of nanocomposites.