NiSe2/Ti3C2 as a promising cathode material for rechargeable dual Mg/Li-ion battery

Abstract NiSe2/Ti3C2 hybrid prepared by the one-step hydrothermal method is used as a cathode material for Mg/Li hybrid ion battery (MLIB) for the first time. The NiSe2/Ti3C2 hybrid shows exciting electrochemical performance, with a reversible capacity of 150 mA h g-1 at a very high current density of 5 A g-1. In contrast, pure NiSe2 only has a capacity of 50 mA h g-1 at 5 A g-1. The sharp improvement can be ascribed to the enhanced conductivity and the lowered charge-transfer resistance (Rct) when Ti3C2 is introduced. Moreover, the working mechanism of NiSe2/Ti3C2 in MLIB is investigated. This work provides a novel method to design cathode materials with high rate performance by combining MXenes with metal selenides.