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

Abstract

Summary: 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@SiOx/Ti3C2 composites for LIBs. Silicon nanosheets and the ultra-thin oxide layer SiOx 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@SiOx attachment and acts as an intercalating agent, enabling WSi@SiOx to enter the interlayer spaces of Ti3C2. The WSi@SiOx/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.

Keywords

• Electrical property
• Nanomaterials
• Energy materials