Structural regulation of covalent organic frameworks for advanced electrocatalysis

Covalent organic frameworks (COFs) have become the most attractive frontier research field in heterogeneous catalysis. Since the geometric and electronic structures of COFs depend greatly on their microenvironment, which, in turn, determine the performances in electrocatalytic processes, the precise integration of atoms of building blocks of COFs to achieve pre-designed compositions, components and functions is the core. In this review, we focus on the latest progress in the structural design, synthesis, characterizations and applications of COFs, with emphasis on electrocatalytic mechanisms. Furthermore, we have proposed a variety of optimizing strategies including structural regulation (including building unit, linkage, and topological structure), pore surface engineering, side chain modification engineering, regulating non-metallic sites, regulating metal sites, regulating single metal active sites, defect engineering, and regulating composite materials to improve the electrocatalytic intrinsic activities of COFs. Experimental and theoretical advances in understanding such microenvironment in association to the electrocatalytic activity and mechanisms are exemplified in the electrochemical applications, including H2/O2 evolution reactions and O2/CO2 reduction reactions. Finally, by highlighting the prospects and challenges for structural regulations of COFs, we wish to shed some light on the further development of COFs for electrocatalysis applications.