Polyaniline-modified cetyltrimethylammonium bromide-graphene oxide-sulfur nanocomposites with enhanced performance for lithium-sulfur batteries
polyaniline, graphene oxide–sulfur, lithium–sulfur batteries, long-term cycling
Conductive polymer coatings can boost the power storage capacity of lithium– sulfur batteries. We report here on the design and preparation—by combining a facile and green chemical deposition method with an oxidative polymerization approach—of polyaniline (PANI)-modified cetyltrimethylammonium bromide (CTAB)–graphene oxide (GO)–sulfur (S) nanocomposites with significantly enhanced performance in lithium–sulfur batteries. Such conductive polymer modified CTAB–GO–S nanocomposites as sulfur cathode materials can deliver high specific discharge capacities and long-term cycling performance, i.e., ~970 mAh·g–1 at 0.2 C and ~715 mAh·g–1 after 300 cycles, ~820 mAh·g–1 at 0.5 C and ~670 mAh·g–1 after 500 cycles, ~770 mAh·g–1 at 1 C and ~570 mAh·g–1 after 500 cycles. The capacity decay was as low as 0.036% per cycle at 0.5 C, and 0.051% per cycle at 1 C. Under the same condition, batteries using PANI-modified CTAB–GO–S as cathodes exhibited higher specific capacity and higher average coulombic efficiency compared with CTAB-decorated GO–S and GO–S nano- composites. The improved performance can be attributed to the lower charge transfer resistance and the alleviated dissolution of polysulfides in the PANI- modified CTAB–GO–S cathodes.
Tsinghua University Press
Yongcai Qiu,Wanfei Li,Guizhu Li,Yuan Hou,Lisha Zhou,Hongfei Li,Meinan Liu,Fangmin Ye,Xiaowei Yang,Yuegang Zhang, Polyaniline-modified cetyltrimethylammonium bromide-graphene oxide-sulfur nanocomposites with enhanced performance for lithium-sulfur batteries. NanoRes.2014, 7(9): 1355–1363