清洁能源化学与材料实验室知识库

Supercapacitors receive numerous attentions for their high charging/discharging rate and robust cycle life, while vanadium nitride with a wide work potential window and comparable specific capacitance promotes the rapid development of negative materials for supercapacitors. In this paper, we report an in-situ preparation for nanohybrid material of carbon nanosphere@vanadium nitride (CNS@VN) derived from metal-organic framework assembled by chitosan, NH₄VO₃ and F127. The biomass of chitosan is used as carbon source, amphiphilic block copolymer of F127 is used as guiding agent, and the vanadium-based compound of NH₄VO₃ is used as precursor. The prepared CNS@VN showed an outstanding specific capacitance as high as 300.4 F/g and the estimated one for VN can reach 1241.3 F/g. Furthermore, a hybrid supercapacitor device of CNS@VN||Co₃O₄ is assembled by using CNS@VN and Co₃O₄ as the negative and positive electrode materials. The device exhibits an excellent energy density of 18.8 Wh/Kg at the power density of 800 W/kg and a prior cycle stability of 77.3% retention. This kind of hybrid material with advanced structure architecture and good electrochemical performance may open up a new design thought for negative electrode materials of supercapacitors.