Mesoporous Poly(3,4-ethylenedioxythiophene):Poly(styrenesulfonate) as Efficient Iodine Host for High-Performance Zinc–Iodine Batteries
Facai Wei, Hengyue Xu, Tingting Zhang, Wenda Li, Lingyan Huang, Yonghui Peng, Haitao Guo, Yuexi Wang, Shaojian Guan, Jianwei Fu, Chengbin Jing, Jiangong Cheng, Shaohua Liu
Abstract
Here, by introducing polystyrenesulfonate (PSS) as a multifunctional bridging molecule to synchronously coordinate the interaction between the precursor and the structure-directing agent, we developed a mesoporous conductive polymer of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) featuring adjustable size in the range of 105–1836 nm, open nanochannels, large specific surface area (105.5 m 2 g –1 ), and high electrical conductivity (172.9 S cm –1 ). Moreover, a large-area ultrathin PEDOT:PSS thin film with well-defined mesopores can also be obtained by controllable growth on various functional interfaces. As an example, we demonstrated that the iodine-loaded mesoporous PEDOT:PSS nanospheres can serve as a promising cathode for aqueous zinc–iodine batteries with high specific capacity (241 mAh g –1 ), excellent rate performance, and superlong 20,000 cycle life. In-depth theoretical calculations and systematic experimental results together reveal that the exposed sulfur- and oxygen-containing functional groups hold strong interactions with iodine species, resulting in effectively anchoring iodine species and inhibiting the shuttling of polyiodide intermediates, thus ensuring the long-term stability of the batteries. This work introduces a member to the family of mesoporous materials as well as porous polymers with versatile applications.