Covalent Organic Frameworks for Photocatalytic Hydrogen Peroxide Evolution.

Covalent organic frameworks (COFs) are considered advanced class materials due to their exotic structural and optical properties. The abundance of starting monomers with variable linkage motifs may give rise to multiple conformations in either 2D or 3D fashion. Tailoring of the abovementioned properties has facilitated the application of COFs in a wide range of applications, which are strongly correlated with energy conversion schemes. Having a crystalline porous character and a large set of donor-acceptor combinations, COFs are expected to make huge impact in photocatalytic processes. In this Review, we present the recent advances in the development of semiconducting COF-based systems towards the photocatalytic hydrogen peroxide evolution. An overview is given about the effect of various parameters on the photocatalytic performance, such as charge transfer tuning, wettability by chemical functionalization, topology, porosity and crystallinity. Various challenges are discussed, and constructive insights are given for the development of highly functional COF-based photocatalysts for HO evolution.