Flexible\nand Freestanding Silicon/MXene Composite\nPapers for High-Performance Lithium-Ion Batteries

Abstract

Silicon has been\ndeveloped as the exceptionally desirable anode\ncandidate for lithium-ion batteries (LIBs), attributing to its highest\ntheoretical capacity, low working potential, and abundant resource.\nHowever, large volume expansion and poor conductivity hinder its practical\napplication. Herein, we fabricate flexible, freestanding, and binder-free\nsilicon/MXene composite papers directly as anodes for LIBs. The Silicon/MXene\ncomposite papers are synthesized via covalently anchoring silicon\nnanospheres on the highly conductive networks based on MXene sheets\nby vacuum filtration. This unique architecture can accommodate large\nvolume expansion, enhance conductivity of composites, prevent restacking\nof MXene sheets, offer additional active sites, and facilitate efficient\nion transport, which exhibits superior electrochemical performance\nwith a high capacity of 2118 mAh·g^–1 at 200\nmA·g^–1 current density after 100 cycles, a\nsteady cycling ability of 1672 mAh·g^–1 at 1000\nmA·g^–1 after 200 cycles, and a rate performance\nof 890 mAh·g^–1 at 5000 mA·g^–1. This work may shed lights on the development of silicon-based anodes\nfor LIBs.