二氧化钛-聚萘/硫正电极的制备及其电化学性能

The Preparation and Electrochemical Performance of Titanium Dioxide-Polyperinaphthalene/Sulfur Cathode Material for Lithium-Sulfur Battery

以3,4,9,10-二萘嵌苯(PTCDA)为原料成功合成聚萘(PPN),然后利用硫代硫酸钠为硫源,通过化学还原法制备聚萘/硫(PPN/S)复合材料,接着在PPN/S外表面包覆一层二氧化钛(Ti O2),最后制备出二氧化钛-聚萘/硫(Ti O2-PPN/S)复合材料.采用扫描电镜、X-射线衍射和热重分析对复合材料Ti O2-PPN/S进行表征;采用充放电测试系统和电化学工作站对Ti O2-PPN/S电极的电化学性能进行测试.结果表明:PPN/S复合材料表面被Ti O2成功包覆,制得一种新型Ti O2-PPN/S复合材料;Ti O2-PPN/S电极具有良好的循环稳定性,在电流密度为400 m A·g-1时,首次放电容量达到1 334.8 m A·h·g-1,循环150次后,放电容量仍保持在691.4 m A·g-1;与含硫量相当的PPN/S电极相比,Ti O2-PPN/S电极具有更佳的电化学性能.

Poly-peri-naphthalene has been prepared by 3,4,9,10-perylenetetracarboxylic acid ahydride,sodium thiosulfate was as sulfur source,and poly-peri-naphthalene / sulfur was prepared,then poly-peri-naphthalene / sulfur was wrapped by titanium dioxide. At last,Ti O2-PPN / S was synthesized. The Ti O2-PPN / S composite material was characterized by SEM,XRD and TGA. The electrode of Ti O2-PPN / S was tested by charge and discharge system and electrochemical workstation. The results show Ti O2-PPN / S composite material was successfully synthesized. The electrode of Ti O2-PPN / S has a good cycle property,the first discharge specific capacity is 1 334. 8m A · h · g- 1at400 m A·h·g- 1,after 150 cycles,the discharge special capacity still maintain 691. 4 m A·g- 1. To comparative sulfur content of PPN / S electrode,the electrode Ti O2-PPN / S is better.