1 T-VSe2 Nanoparticles cooperated with reduced graphene oxide as a superior cathode material for rechargeable Mg-ion batteries

Abstract

Transition metal disulfides (TMDs) have received widespread attention and are expected to be a kind of potential energy material because of their unique structures. In this paper, we obtained 1 T-VSe2 nanoparticles cooperated with reduced graphene oxide (1 T-VSe2@rGO) composite in APC electrolyte environment via a simple hydrothermal method, and it was used as the cathode material of the second generation rechargeable magnesium ion battery (RMIB). The test results show that the 1 T-VSe2@rGO composite cathode material has an excellent reversible capacity (235.5 mA h g−1 at 50 mA g−1), and a prominent cycle life (62.7 % of the initial capacitance is maintained at 50 mA g−1 after 500 consecutive cycles). The rate capability of 46 % initial capacitance is received when the current density reaches 1000 mA g−1. We also evaluated the influence of Mg-insertion behavior on RMIBs based on the cathode of 1 T-VSe2@rGO composite with the first-principles Density Functional Theory (DFT) computations. The results prove that the composites based on 1 T-VSe2@rGO have great development potential as cathode materials for RMIBs.