Side‐Chain Modification in Covalent Triazine Frameworks for Promoting Photocatalytic H 2 O 2 Production
Ren Rui, Wanyi Deng, Keshan Tang, Yang Xia, Chao Yang, Changwei ShiABSTRACT
Photocatalytic H 2 O 2 production from O 2 and water using covalent triazine frameworks (CTF) offers a sustainable alternative to the fossil‐dependent anthraquinone process, but its scalability is severely constrained by their low charge transfer efficiency and rapid charge recombination. Herein, we proposed a side‐chain engineering strategy to optimize the electron density of the acceptor units by introducing methyl, hydrogen, or idoine substituents into the covalent triazine framework scaffolds, yielding CH 3 ‐CTF, H‐CTF, and I‐CTF, respectively. The obtained I‐CTF exhibited significantly enhanced crystallinity, a narrowed bandgap, and optimized bonding electron polarization, leading to a notable H 2 O 2 yield of 2320.2 µmol g −1 h −1 in pure water and O 2 atmosphere, surpassing its hydrogen‐ and methyl‐substituted counterparts (H‐CTF and CH 3 ‐CTF, respectively). Besides, density functional theory (DFT) results further confirm that strategic iodination not only facilitates charge carrier separation and induces local electron polarization but also contributes to the O 2 adsorption, thereby endowing a maximum 2e − oxygen reduction reaction (ORR) of CTFs photocatalyst. This work demonstrated that side‐chain electronic properties are pivotal in steering photocatalytic efficiency, which is meaningful for further design of efficient CTF‐based photocatalysts for H 2 O 2 production.