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

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 (R_ct) 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.