Interface engineering of 0D-2D CoSe₂/ZnSe@MXene heterostructured electrodes for high-performance lithium-ion batteries

High-capacity conversion-type anodes with high volume expansion and low conductivity face limitations in meeting the high energy density demands of lithium-ion batteries. Herein, MOF-derived CoSe₂/ZnSe bimetallic selenide nanoparticles are confined in layered Ti₃C₂T_x MXene (CoSe₂/ZnSe@MX) as electrodes for high-performance lithium-ion batteries by an in situ self-assembly and selenization strategy. The interconnected conductive MXene networks can not only provide highways for charge transfer but can also effectively accommodate large volume expansion, improving structural stability. Meanwhile, the bimetallic CoSe₂/ZnSe nanoparticles with heterostructures and Se vacancies offer abundant redox reaction sites, promote Li-ion diffusion, and enhance Li-ion adsorption. Thus, the CoSe₂/ZnSe@MX electrodes exhibit a remarkable capacity of 830.8 mA h g⁻¹ at 0.1 A g⁻¹, high-rate capability of 290.8 mA h g⁻¹ at 5 A g⁻¹, and superior cycling stability with 63.1% capacity retention after 2000 cycles. Furthermore, the full cell demonstrated practical applicability with a high capacity of 156 mA h g⁻¹ at 0.1C. This facile technique is promising for constructing high-performance energy storage devices.