Key Laboratory of Colloid and Interface Chemistry, Ministry of Education School of Chemistry and Chemical Engineering, Shandong University , Jinan 250100, P.R. China.
State Key Laboratory of Crystal Materials, Shandong University , Jinan 250100, P.R. China.
ACS Appl Mater Interfaces. 2016 Jul 27;8(29):18797-805. doi: 10.1021/acsami.6b04444. Epub 2016 Jul 15.
VS4 as an electrode material in lithium-ion batteries holds intriguing features like high content of sulfur and one-dimensional structure, inspiring the exploration in this field. Herein, VS4 submicrospheres have been synthesized via a simple solvothermal reaction. However, they quickly degrade upon cycling as an anode material in lithium-ion batteries. So, three conductive polymers, polythiophene (PEDOT), polypyrrole (PPY), and polyaniline (PANI), are coated on the surface to improve the electron conductivity, suppress the diffusion of polysulfides, and modify the interface between electrode/electrolyte. PANI is the best in the polymers. It improves the Coulombic efficiency to 86% for the first cycle and keeps the specific capacity at 755 mAh g(-1) after 50 cycles, higher than the cases of naked VS4 (100 mAh g(-1)), VS4@PEDOT (318 mAh g(-1)), and VS4@PPY (448 mAh g(-1)). The good performances could be attributed to the improved charge-transfer kinetics and the strong interaction between PANI and VS4 supported by theoretical simulation. The discharge voltage ∼2.0 V makes them promising cathode materials.
VS4 作为锂离子电池的电极材料，具有高硫含量和一维结构等有趣的特点，激发了该领域的探索。本文通过简单的溶剂热反应合成了 VS4 亚微球。然而，作为锂离子电池的阳极材料，它们在循环过程中很快降解。因此，将三种导电聚合物，聚噻吩（PEDOT）、聚吡咯（PPY）和聚苯胺（PANI）涂覆在表面，以提高电子导电性、抑制多硫化物的扩散，并修饰电极/电解质之间的界面。其中聚苯胺（PANI）的效果最佳。它将首次循环的库仑效率提高到 86%，并在 50 次循环后保持 755 mAh g(-1) 的比容量，高于裸 VS4（100 mAh g(-1)）、VS4@PEDOT（318 mAh g(-1)）和 VS4@PPY（448 mAh g(-1)）的情况。良好的性能可归因于理论模拟所支持的电荷转移动力学的改善和聚苯胺与 VS4 之间的强相互作用。放电电压约为 2.0 V 使它们成为有前途的阴极材料。
