纳米硒化铁/三维多孔碳负极材料的制备及其电化学性能

Preparation and electrochemical performance of nanoscale iron selenide/three-dimensional porous carbon negative materials

作为钠离子电池负极材料,FeSe_(2)在循环过程中易发生团聚,导致循环性能下降,通过制备碳基复合材料可解决此问题。本文以NaCl为模板,利用冷冻干燥技术制备了三维多孔碳(3DPC),同时采用水热法制备了FeSe_(2)、FeSe_(2)/3DPC负极材料,通过调节FeSe_(2)含量制备了不同比例的FeSe_(2)/3DPC复合材料,考察了复合材料的电化学性能。结果表明:FeSe_(2)/3DPC复合材料具有比FeSe_(2)和3DPC更优异的电化学性能,在1.0 C倍率下,初始放电比容量为823 mA·h/g,循环1000周后可逆放电比容量保持率为25.2%。当FeSe_(2)质量分数为40%时,材料具有最高的放电比容量;在1.0 C倍率下,循环1000周后可逆放电比容量为150 mA·h/g,电化学性能最佳。本研究成果可为钠离子电池负极材料的设计提供参考。

As the negative electrode material for sodium ion batteries,FeSe 2 is prone to agglomeration during cycling,leading to a decrease in cycling performance.This problem can be solved by preparing carbon based composite materials.This article uses NaCl as a template and freeze-drying technology to prepare three-dimensional porous carbon(3DPC).At the same time,FeSe 2 and FeSe 2/3DPC negative electrode materials were prepared by hydrothermal method.Different proportions of FeSe 2/3DPC composite materials were prepared by adjusting the FeSe 2 content,and the electrochemical properties of the composite materials were investigated.The results showed that FeSe 2/3DPC composite material had better electrochemical performance than FeSe 2 and 3DPC.At a rate of 1.0 C,the initial discharge specific capacity was 823 mA·h/g,and the reversible discharge specific capacity retention rate was 25.2%after 1000 cycles.When the mass fraction of FeSe 2 is 40%,the material has the highest discharge specific capacity;At the rate of 1.0 C,the reversible discharge specific capacity is 150 mA·h/g after 1000 cycles,and the electroche-mical performance is optimal.The research results can provide reference for the design of negative electrode materials for sodium ion batteries.