Research progress on metal and covalent organic framework-based materials for high-performance supercapacitors

Metal-organic frameworks (MOFs) and covalent organic frameworks (COFs) are both a series of crystalline porous materials. MOFs, COFs and their derivatives have attracted much attention in energy storage devices due to their highly ordered structures, large surface areas, tunable pore sizes and topologies, and well-defined redox-active porous skeletons. They must also have structural stability, an abundance of redox-active sites and high electronic conductivity for use in high-performance supercapacitor electrodes. We review the recent research progress on the design of MOFs and COFs, and their hybrids with conductive materials (e.g. conductive polymer, graphene and carbon nanotubes), and MOF- and COF-derived carbon materials. Their chemical and physical properties, capacitive performance and structure-property relationships are discussed. Finally, the challenges and prospects of MOF- and COF-based electrode materials are presented.