Preparation of WSi@SiOx/Ti3C2 from photovoltaic silicon waste as high-performance anode materials for lithium-ion batteries

Silicon anodes hold promise for future lithium-ion batteries (LIBs) due to their high capacity, but they face challenges such as severe volume expansion and low electrical conductivity. In this study, we present a straightforward and scalable electrostatic self-assembly method to fabricate WSi@SiO_x/Ti₃C₂ composites for LIBs. Silicon nanosheets and the ultra-thin oxide layer SiO_x serve as sufficient buffers against volume changes, while the layered MXene enhances the electrical conductivity of the composite and promoted Li⁺/e^- transport. Additionally, cationic surfactant-treated Ti₃C₂ provides more active sites for WSi@SiO_x attachment and acts as an intercalating agent, enabling WSi@SiO_x to enter the interlayer spaces of Ti₃C₂. The WSi@SiO_x/Ti₃C₂ electrodes significantly improved electrochemical performance, achieving a capacity of 1,130 mAh g^-1 after 800 charge/discharge cycles at 500 mA g^-1. This study not only presents a straightforward pathway for high-value utilization of silicon waste but also offers a feasible route for preparing high-performance and cost-effective silicon-based LIBs.