Li Tao, Ding Bing, Wang Jie, Qin Zongyi, Fernando Joseph F S, Bando Yoshio, Nanjundan Ashok Kumar, Kaneti Yusuf Valentino, Golberg Dmitri, Yamauchi Yusuke
International Research Center for Materials Nanoarchitechtonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, and College of Material Science and Engineering, Donghua University, Shanghai 201620, China.
ACS Appl Mater Interfaces. 2020 Apr 1;12(13):14993-15001. doi: 10.1021/acsami.9b18883. Epub 2020 Mar 18.
Organic polymers have attracted significant interest as electrodes for energy storage devices because of their advantages, including molecular flexibility, cost-effectiveness, and environmentally friendly nature. Nevertheless, the real implementation of polymer-based electrodes is restricted by their poor stability, low capacity, and slow electron-transfer/ion diffusion kinetics. In this work, a sandwich-structured composite of ordered mesoporous polydopamine (OMPDA)/TiCT has been fabricated by in situ polymerization of dopamine on the surface of TiCT via employing the PS--PEO block polymer as a soft template. The OMPDA layers with vertically oriented, accessible nanopores (∼20 nm) provide a continuous pore channel for ion diffusion, while the TiCT layers guarantee a fast electron-transfer path. The OMPDA/TiCT composite anode exhibits high reversible capacity, good rate performance, and excellent cyclability for lithium-ion batteries. The in situ transmission electron microscopy analysis reveals that the OMPDA in the composite only shows a small volume expansion and almost preserves the initial morphology during lithiation. Moreover, these in situ experiments also demonstrate the generation of a stable and ultrathin solid electrolyte interphase layer surrounding the active material, which acts as an electrode protective film during cycling. This study demonstrates the method to develop polymer-based electrodes for high-performance rechargeable batteries.
有机聚合物因其具有分子柔韧性、成本效益和环境友好性等优点，作为储能器件的电极受到了广泛关注。然而，基于聚合物的电极的实际应用受到其稳定性差、容量低以及电子转移/离子扩散动力学缓慢的限制。在这项工作中，通过使用PS-PEO嵌段聚合物作为软模板，在TiCT表面原位聚合多巴胺，制备了一种有序介孔聚多巴胺（OMPDA）/TiCT的三明治结构复合材料。具有垂直取向、可及纳米孔（约20 nm）的OMPDA层为离子扩散提供了连续的孔道，而TiCT层保证了快速的电子转移路径。OMPDA/TiCT复合负极对锂离子电池表现出高可逆容量、良好的倍率性能和优异的循环稳定性。原位透射电子显微镜分析表明，复合材料中的OMPDA在锂化过程中仅表现出小的体积膨胀，并且几乎保留了初始形态。此外，这些原位实验还证明了在活性材料周围生成了稳定且超薄的固体电解质界面层，该界面层在循环过程中起到电极保护膜的作用。这项研究展示了开发用于高性能可充电电池的基于聚合物的电极的方法。
