NaCl-template-assisted freeze-drying synthesis of 3D porous carbon-encapsulated V2O3 for lithium-ion battery anode

Abstract Vanadium trioxide material have attracted enormous attention recently, owing to their high theoretical capacity for use as anodes in lithium ion batteries. However, the unstable structure of V2O3 limits its practical application. It is challenge to develop a simple, scalable and economical technique to produce 3D porous carbon-based V2O3 materials with high structure stability. In this work, a facile NaCl template-assisted freeze-drying strategy was used to produce 3D porous carbon-encapsulated V2O3 (3D porous V2O3@C) composites with highly crystalline architecture, uniformly carbon-encapsulated V2O3 nanoparticles and interconnected conductive carbon networks. The resultant 3D porous V2O3@C anode exhibits significantly enhanced rate performance (797 mAh/g at 0.1 A/g, 715 mAh/g at 0.3 A/g, 658 mAh/g at 0.5 A/g, 598 mAh/g at 1 A/g, 480 mAh/g at 3 A/g and 426 mAh/g at 5 A/g) and long-term cycling stability (506 mAh/g at 5A/g after 2000 cycles). The present work suggests a scalable preparation of the 3D porous carbon-based V2O3 materials, which may be extended to preparing other 3D porous materials for potential applications in energy storage, catalysis and sensors.