Sandwich-like silicon/Ti3C2Tx MXene composite by electrostatic self-assembly for high performance lithium ion battery

Abstract

Silicon has been regarded as a promising anode materials for lithium ion battery. However, large volume change during lithiation/delithiation process impedes its application for energy storage. Two-dimensional titanium carbide or carbonitride nanosheet, known as MXene, possesses layered-stacked structure and high electrical conductivity. So MXene has a great potential to improve the cycle life of silicon anode because its layered-stacked structure can accommodate the volume expansion of silicon. Herein, we present a facile process to prepare sandwich-like silicon/Ti3C2Tx MXene composite directed by electrostatic self-assembly. This unique architecture could accommodate silicon expansion during lithiation and enhance electronical conductivity. The silicon/Ti3C2Tx MXene composite delivers an initial reversible capacity of 1067.6 mAh g−1 at a current of 300 mA g−1. Moreover, it shows a steady cycling ability of 643.8 mAh g−1 at 300 mA g−1 after 100 cycles. This work may shed lights on the development of high energy density silicon-based anode materials for lithium ion battery.