Jun Gao, Lichao Wang, Shunwei Huang, Hao Du, Huayue Zhu, Derek Hao, Yanling Wu, Qi Wang, Limin Jin,Optimizing exciton interactions in covalent organic frameworks for boosting photocatalytic hydrogen peroxide production toward water decontamination,Chinese Chemical Letters,37(8)2026,112283,https://doi.org/10.1016/j.cclet.2025.112283.
(https://www.sciencedirect.com/science/article/pii/S1001841725014603)
Abstract: Solar-driven hydrogen peroxide (H2O2) production presents a sustainable alternative to energy-intensive industrial methods, yet its efficiency using covalent organic frameworks (COFs) suffer from energy loss caused by strong exciton interactions. Herein, we designed COFs with donor-π-acceptor (D-π-A) architectures, using 2,5-dimethoxy-1,4-benzenedicarboxaldehyde as the D unit and optimizing the N-containing π-bridge units. The resulting TAPT–OCH3 COF, incorporating 4,4′,4′'-(1,3,5-triazine-2,4,6-triyl)trianiline as the A unit, demonstrated the extended electron pathways and the reduced exciton recombination, markedly boosting photocatalytic performance. Experimental results revealed that TAPT–OCH3 achieved a solar-to-chemical efficiency of 0.23?% and a quantum yield of 2.21?% at 420?nm, outperforming most reported COFs and metal-free catalysts. In situ characterization and theoretical calculations revealed that the TAPT–OCH3 enhances charge separation to drive H2O2 production via a 2e? oxygen reduction pathway, while its tailored electronic structure simultaneously improves the 1e? water oxidation process. Crucially, TAPT–OCH3 maintained high efficacy across diverse water sources and continuous-flow reactors under natural sunlight, enabling scalable H2O2 synthesis for water purification. Life cycle assessment confirmed the application stability of this material, underscoring its potential for sustainable environmental remediation. This work establishes a design paradigm for optimizing exciton dynamics in COF, highlighting the critical role of structural design for artificial H2O2 photosynthesis.
Keywords: Covalent organic frameworks; Donor-π-acceptor; Exciton binding energy; Photocatalytic H2O2 production; Water decontamination