N-MXene/S复合材料在锂硫电池中的研究

N-Mxene/S composites study of lithium-sulfur batteries

锂硫电池实际能量密度不高、硫导电性差及多硫化物的穿梭效应等缺陷影响其商业化应用。采用层状MXene(TiC)与CH_(4)N_(2)O、LiOH合成多层N-MXene(TiC)复合材料,并采用高温固相法与硫(S)复合作为锂硫电池正极材料。结果表明:N-TiC/S复合材料的比表面积增加,层与层的间隙增大,不仅活性物质硫的导电性提高,抑制多硫化物的穿梭效应;同时具有良好的电化学稳定性,100圈循环后放电比容量仍保持850 mAh/g,效率保持在95%以上。

The defects of lithium-sulfur batteries such as low actual energy density,poor sulfur conductivity and the shuttle effect of polysulfide affect their commercial application.Multi-layer N-MXene(TiC)composite materials were synthesized by layered MXene(TiC),CH_(4)N_(2)O and LiOH,and sulfur(S)composite materials were used as anode materials of lithium-sulfur batteries by high-temperature solid-state method.The results show that when the specific surface area of N-TiC/S composites increases and the gap between layers increases,not only the electrical conductivity of active sulfur,but also the shuttle effect of polysulfide are inhibited.Meanwhile,it has good electrochemical stability.After 100 cycles,the discharge specific capacity still remains 850 mAh/g,and the efficiency remains above 95%.