A Free-Standing alpha-MoO3/MXene Composite Anode for High-Performance Lithium Storage

Replacing the commercial graphite anode in Li-ion batteries with pseudocapacitor materials is an effective way to obtain high-performance energy storage devices. alpha-MoO3 is an attractive pseudocapacitor electrode material due to its theoretical capacity of 1117 mAh g(-1). Nevertheless, its low conductivity greatly limits its electrochemical performance. MXene is often used as a 2D conductive substrate and flexible framework for the development of a non-binder electrode because of its unparalleled electronic conductivity and excellent mechanical flexibility. Herein, a free-standing alpha-MoO3/MXene composite anode with a high specific capacity and an outstanding rate capability was prepared using a green and simple method. The resultant alpha-MoO3/MXene composite electrode combines the advantages of each of the two components and possesses improved Li+ diffusion kinetics. In particular, this alpha-MoO3/MXene free-standing electrode exhibited a high Li+ storage capacity (1008 mAh g(-1) at 0.1 A g(-1)) and an outstanding rate capability (172 mAh g(-1) at 10 A g(-1)), as well as a much extended cycling stability (500 cycles at 0.5 A g(-1)). Furthermore, a full cell was fabricated using commercial LiFePO4 as the cathode, which displayed a high Li+ storage capacity of 160 mAh g(-1) with an outstanding rate performance (48 mAh g(-1) at 1 A g(-1)). We believe that our research reveals new possibilities for the development of an advanced free-standing electrode from pseudocapacitive materials for high-performance Li-ion storage.