N-doped Ni-Co bimetallic derived hollow nano-framework cubes anchored on 3D reduced graphene aerogel with enhanced sodium ion batteries performance

Developing advanced electrode materials for sodium ion batteries (SIBs) to meet the urgent need of high performance is still challenging. In this study, a novel SIBs negative electrode composite material (N/(Ni, Co)Se₂ NFCs@RGOA) was prepared by loading N-doped bimetal derived nano-framework cubes (N/(Ni, Co)Se₂ NFCs) on reduced graphene oxide aerogel (RGOA). The nano-size and hollow cage structure of N/(Ni, Co)Se₂ NFCs cooperate with the layered branched carbon skeleton and porous structure of RGOA to accelerate the reaction kinetics, therefore alleviate the structure collapse caused by volume expansion, and boost the conductivity of the material. The characterization and electrochemical testing results show that the electrode material has remarkable electrochemical performance (reversible capacity of 497 mA h g⁻¹ at 0.1 A g⁻¹), capacity stability (395 mA h g⁻¹ after 200 cycles) and excellent rate performance (389 mA h g⁻¹ at the current density of 2 A g⁻¹). The as designed electrode material will play a significant role to benefit the development of SIBs and advanced electrical storage applications.