G. W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
Division of Advanced Materials, Korea Research Institute of Chemical Technology, Gaejeongro 141, Daejeon, 305-600, South Korea.
Small. 2018 Aug;14(34):e1801236. doi: 10.1002/smll.201801236. Epub 2018 Jul 31.
Polydopamine, a functional coating material, is redox active as cathode materials for both Li- and Na-ion batteries or hybrid capacitors. Here, a polydopamine coating onto 3D graphene framework is introduced through a simple hydrothermal process, during which graphene oxide serves not only as an oxidant for assisting the polymerization of dopamine, but also as a template for the conformal growth of polydopamine. High-density films are fabricated by compressing the polydopamine-coated graphene aerogels, which can be directly used as free-standing and flexible cathodes in both Li- and Na-cells. The compact electrodes deliver high capacities of ≈230 mAh g in Li-cells and ≈211 mAh g in Na-cells based on the total mass of electrodes. These compact electrodes also exhibit exceptional cycling stability and high rate performance due to the unique structure in which polydopamine is uniformly coated on the 3D structured graphene.
聚多巴胺是一种功能性的涂层材料，作为锂电池和钠离子电池或混合电容器的阴极材料具有氧化还原活性。在此，通过简单的水热过程将聚多巴胺涂层引入 3D 石墨烯骨架中，在此过程中，氧化石墨烯不仅用作辅助多巴胺聚合的氧化剂，而且还用作聚多巴胺的保形生长的模板。通过压缩聚多巴胺涂覆的石墨烯气凝胶来制造高密度薄膜，该气凝胶可以直接用作锂电池和钠电池中的独立且灵活的阴极。基于电极的总质量，紧密的电极提供了 ≈230 mAh g 在锂电池和 ≈211 mAh g 在钠离子电池中的高容量。由于聚多巴胺均匀地涂覆在 3D 结构的石墨烯上，这种独特的结构使这些紧密的电极具有出色的循环稳定性和高倍率性能。
