Authors: Wei Lan, Banglu Wei, Yongming Jin, Shenglei Xu, Huixin Zhou, Yiran Wu, Qiu Liu, Peng Chen, Junkai Wang, Xiaoyu Zhao, Hong Meng, Lang Liu, Duozhi Wang, Haibao Huang, Yen Wei, Quan Zhu, Yuming Yu
Published: 2025-03-17
Source: Full article
AbstractCovalent organic frameworks (COFs) are widely studied for hydrogen peroxide (H₂O₂) photosynthesis, with 3D COFs standing out for their porous structures and chemical stability. However, the difficult preparation of 3D COFs and the low efficiency in separating photo‐generated electrons and holes (e− and h+) limits the efficient production of H2O2. In this study, two kinds of [6+3] 3D COFs (XJU‐1, XJU‐2) with significant charge separation, achieving record‐breaking H₂O₂ photocatalysis rates of 34 777 and 11 922 µmol g⁻¹ h⁻¹, respectively. XJU‐1's superior efficiency stems from its larger pores, enhancing material transport and oxygen (O2) activation. Experimental and theoretical studies have demonstrated that triptycene monomers achieve significant charge separation toward triazine via imine bonds. Moreover, the dimer's smaller singlet‐triplet energy gap (∆ES‐T) and triptycene's orthogonal configuration enhance singlet oxygen (1O2) production, enabling multiple H2O2 generation pathways. Ultimately, through the oxygen reduction reaction (ORR) pathway, rapid generation of H2O2 can be achieved at multiple catalytic sites. XJU‐1 mainly follows a mixed pathway involving 1e−‐ORR and 2e−‐ORR, and XJU‐2 primarily follows the 2e−‐ORR pathway, respectively. These open the door of triptycene‐based 3D COFs applied in continuous, efficient, and stable photosynthesis of H2O2.