@article{Wu2026, 
author = {Chongbei Wu and Guanxia Dai and Liying Huang and Yuefan Guan and Yifan Sun and Yuanxin Dong and Zike Zhang and Xuan Li and Zhuan Wang and Jizhou Jiang},
title = {Localized asymmetric electron distribution in COFs promotes efficient photocatalytic H2O2},
year = {2026},
journal = {Nano Research},
keywords = {electrostatic interaction, covalent organic frameworks, localized asymmetric electron distribution, O2 adsorption, H2O2 photosynthesis},
url = {https://www.sciopen.com/article/10.26599/NR.2026.94908633},
doi = {10.26599/NR.2026.94908633},
abstract = {In covalent organic frameworks (COFs), the highly symmetric skeleton limits O2 adsorption and weakens the thermodynamic driving force of the two-electron oxygen reduction reaction (2e- ORR), thus restricting photocatalytic efficiency. In this study, we modulated the local arrangement of fluorine atoms in COFs (para- and ortho-fluorinated, named Fp-COFs and Fo-COFs) to create an asymmetric electronic distribution, which supplies effective O2-adsorption sites, strengthens the driving force for 2e- ORR and ultimately elevates the photocatalytic activity. Theoretical analysis shows that asymmetric fluorination delocalizes the lone-pair electrons of F atoms to adjacent carbons, producing a discretized electron distribution that improves O2 adsorption at imine bonds. The increased electron density on these carbons facilitates electron transfer into the π* orbital of adsorbed O2, accelerating ·OOH* intermediate formation and lowering the Gibbs free energy barrier of the 2e- pathway. Consequently, a quantum yield of 8.8 % for H2O2 photosynthesis in pure water is achieved. This work provides a new approach for tuning local electron distribution in COFs, offering guidance for the rational design of efficient photocatalytic materials and broadening the application prospects of asymmetric electronic structures.}
}