具有长循环稳定性的钾离子负极材料Sb_(2)Se_(3)@N-C的制备及其电化学性能

Preparation and Electrochemical Performance of Sb_(2)Se_(3)@N-C with Long Cycle Stability Anode Material for Potassium-ion Batteries

与匮乏的锂资源相比,钾元素在自然界中储量丰富,使得钾离子电池被视为锂离子电池的替代品。Sb_(2)Se_(3)因较高的理论比容量(669 mAh/g)而被视为钾离子电池负极材料的候选材料。但Sb_(2)Se_(3)嵌钾会造成两倍以上的体积膨胀,和生成K_(2)Se导致容量快速衰减和导电性差。本文通过简单的水热反应、高温煅烧制得Sb_(2)Se_(3)@N-C,并将其作为钾离子电池负极材料进行电化学性能测试。结果表明:Sb_(2)Se_(3)@N-C表现良好的稳定性,在1.6 A/g的电流密度下循环1000次仍有180 mAh/g的容量。

Compared with the lithium resources,potassium is abundant in nature,which makes potassium ion battery as a substitute for lithium-ion battery.Sb_(2)Se_(3) is considered as a candidate anode material for potassium ion batteries because of its high theoretical specific capacity(669 mAh/g).However,the intercalation of K+will cause more than twice the volume expansion and the formation of K_(2)Se,leads to rapid capacity attenuation and poor conductivity.In this paper,by simple hydrothermal reaction and high-temperature calcination,the product was obtained Sb_(2)Se_(3)@N-C.It was used as the anode material of potassium ion battery for electrochemical performance test,and showed very good stability.Sb_(2)Se_(3)@N-C still has 180 mAh/g capacity after 1000 cycles at the current density of 1.6 A/g.