石墨烯在平面微型超级电容器中的应用进展与展望

Progress and prospects of graphene for in-plane micro-supercapacitors

微型超级电容器具有高功率密度和长循环寿命,有望为物联网设备供电。然而,较低的能量密度阻碍了微型超级电容器的实际应用。电极材料是影响微型超级电容器性能的一个重要因素。石墨烯由于具有比表面积大和导电性高等优势,是微型超级电容器的理想电极材料。当石墨烯用于具有平面构型的微型超级电容器时,其二维表面与电解质离子的传输方向平行,有利于提高电极的离子可及性。因此,构建石墨烯基平面微型超级电容器,引起了研究人员的极大兴趣。本文从电极材料设计的角度,总结了平面微型超级电容器用石墨烯和石墨烯基材料的最新研究进展。这些电极材料包括通过化学气相沉积、液相剥离、氧化石墨烯还原、激光诱导和杂原子掺杂方法获得的石墨烯,及石墨烯基复合材料(碳纳米管/石墨烯、过渡金属氧化物/石墨烯、导电聚合物/石墨烯和二维材料/石墨烯)。讨论了石墨烯基平面微型超级电容器面临的挑战和机遇,并展望了未来的研究方向和发展趋势。

Micro-supercapacitors hold great promise for powering the Internet of Things devices owing to their high power dens-ity and long cycling life.However,the limited energy density hinders their practical use.Electrode materials play an important role in the performance of micro-supercapacitors.With the advantages of a large specific surface area and a high electrical conductivity,graphene has been considered a good candidate for the electrode material of micro-supercapacitors.The two-dimensional surface of graphene is parallel to the direction of transport of the electrolyte ions for micro-supercapacitors with an in-plane structure,which helps improve the ion accessibility of the electrodes.Therefore,the construction of graphene-based in-plane micro-supercapacitors has aroused great interest among researchers.Here,we summarize the recent advances in graphene and graphene-based materials for in-plane micro-supercapacitors from the perspective of electrode material design.The electrode materials include graphenes pro-duced by chemical vapor deposition,liquid-phase exfoliation,reduction of graphene oxide,laser induction and heteroatom doping,as well as graphene-based composites,such as carbon nanotube/graphene,transition metal oxide/graphene,conducting polymer/graphene and two-dimensional material/graphene composites.Challenges and opportunities in graphene-based in-plane mi-cro-supercapacitors are discussed,and future research directions and development trends are proposed.