Ni2P nanosheets modified N-doped hollow carbon spheres towards enhanced supercapacitor performance

Abstract

Carbon materials have been attracted attention because of high supercapacitor activity. In this work, N-doped mesoporous hollow carbon spheres coated with Ni2P nanosheets are prepared by hydrothermal and calcination processes using a SiO2 template. N element doping changes the structure of hollow carbon spheres. Ni2P nanosheets are grown uniformly on the surface of the N-doped carbon spheres (N-CS). Due to the unique atomic arrangement of N-CS, the hollow mesoporous structure, and coupling with the unique composition of Ni2P nanosheets, N–C@Ni2P composites exhibit excellent electrochemical performance as supercapacitor electrodes with high specific capacitance and cycle stability under high current density. When the current density is 10 A g−1, the specific capacitance is 1320.4 F g−1. The capacitance retention rate after 1500 cycles is 76%. In the case of a current density of 20 A g−1, the specific capacitance is still up to 1062 F g−1. This method provides a fine strategy for designing high-performance supercapacitors based on carbon materials.