Facile preparation of sulfur/nitrogen co-doped graphene coupled with Ni(OH)2 for battery-type electrode with superior electrochemical performance

Abstract

A novel hybrid material composed of Ni(OH)2 nanoplates and sulfur/nitrogen co-doped reduced graphene oxide frameworks (SN-RGO) was successfully prepared by a hydrothermal method. The co-doping of S and N provides a large number of structural defects on the graphene surface, which makes the C atoms more active and increases the number of active sites. The as-obtained SN-RGO/Ni(OH)2 electrode delivers an excellent discharge capacity (363.4 mAh/g at 0.2C), which is better than those of the Ni(OH)2 hybrid with un-doped or N-doped graphene. This superior performance can be attributed to the increased number of defects and active sites of SN-RGO, and the loose sandwich-like structure. The SN-RGO/Ni(OH)2 composites are promising candidates for battery-type electrode materials for alkaline secondary batteries.