Wire-like NiCo2O4 anchored on reduced graphene oxide with enhanced electrochemical performance for sodium-ion batteries

Abstract

In this work, NiCo2O4 nanowires/reduced graphene oxide (NCO/RGO) composites were synthesized through a simple hydrothermal method followed by a thermal annealing process. When employed as anodes for sodium-ion batteries (SIBs), the NCO/RGO composites exhibit a high maximum capacity of 422.1 mAh g−1 after 50 cycles at a current density of 100 mA g−1. Furthermore, even at a high current density of 2000 mA g−1, a capacity of 275.1 mAh g−1 is still maintained, which surpasses those of most previously reported NCO. The attractive electrochemical performance of NCO/RGO composites is attributed to the synergistic effect between NCO and RGO, and enables them to be a very promising candidate for high performance SIBs.