Abstract
The abundant and wide distribution of sodium makes sodium-ion batteries (SIBs) one of the most promising battery technologies to supplement the current lithium-ion batteries in large-scale energy storage. However, the available anode materials are still far from satisfactory to enable the high-performance operation of SIBs. Here, a V2S3@C@V2S3 heterostructure anode is developed by one-step in-situ conversion of V2CTx MXene in CS2 ambient. The resultant electrode has abundant hetero-interfaces and controllable V2S3 crystallinity and size. In this unique design, the carbon interlayer in the anode behaves like a flexible conductive support and an anchoring network. The ultrathin V2S3 nano -sheets and the V2S3-C heterointerfaces enhance the Na thorn adsorption and migration abilities, thus simultaneously mitigating the low conductivity, structural degradation, and sluggish kinetics of V2S3. As a result, this V2S3@C@V2S3 anode achieves a highly reversible capacity (628 mAh/g at 0.1 A/g), excellent rate performance (477 mAh/g at 10A/g), and impressive cycling stability (2000 cycles at 20 A/g, record -high value). This performance is far better than the parent MXene phase. Considering the rich compo-sitional diversity of MXene, the in-situ conversion strategy developed here can be extended to construct a wide range of high-performance electrode materials for advanced batteries.(c) 2022 Published by Elsevier Ltd.