Fabrication of V2CTx/VSe2/V2O3 heterostructure using an in-situ selenization strategy for high performance zinc-ion batteries

MXenes are a promising cathode materials for aqueous zinc ion batteries (AZIBs) due to their layered structure, metallic conductivity, and hydrophilicity. Vanadium diselenide (VSe 2 ) is a typical transition metal dichalcogenide with good metallic properties and high conductivity. In this work, V 2 CT x was successfully synthesized by etching V 2 AlC with a hydrochloric acid solution of sodium fluoride, and surface selenization of V 2 CT x was accomplished using a high-temperature solid-state reaction. During the reaction process, some vanadium atoms on the surface of V 2 CT x were selenized and transformed into small VSe 2 nanosheets, while oxygen-containing groups form V 2 O 3 with vanadium atoms, and resulting in a V 2 CT x /VSe 2 /V 2 O 3 heterostructure material. The components of the nanohybrid were tuned by changing the mass ratio of selenium to V 2 CT x and the optimized VSe 2 –14 composite simultaneously achieved high specific capacitance (224.8 mAh/g after 200 cycles at 0.5 A g −1 ), excellent rate performance (126.2 mAh/g at 10 A g −1 ), and satisfactory cycle stability (141.3 mAh/g after 1300 cycles at 5 A g −1 ). This study provides a reference for the application of MXene-based materials in aqueous zinc ion batteries.