Photocatalytic Selective Oxidation of Toluene over Chlorine-Coordinated MIL-101(Fe) under Ambient Conditions

• Published in: Langmuir Vol. 40; no. 40; pp. 20841 - 20847
• Main Authors: Wu, Zeqi, Niu, Feng, Yao, Wenhao, Gao, Siyuan, Chen, Da, Huang, Yuexiang
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 08.10.2024
• ISSN: 0743-7463; 1520-5827; 1520-5827
• DOI: 10.1021/acs.langmuir.4c02431

The activation of an inert C­(sp 3)–H bond in selective oxidation of hydrocarbons under mild conditions is a critical and challenging process. Herein, we report a stable chlorine-coordinated metal–organic framework (MOF) photocatalyst, MIL-101­(Fe), for efficient visible-light-driven photocatalytic selective oxidation of toluene to benzaldehyde in air under ambient conditions. Encouragingly, a benzaldehyde formation yield of 3.11 mmol·g–1·h–1 with a selectivity of 92.1% is achieved in 5 h, which is superior to most of the reported works. Based on the experimental results and characterizations, the high catalytic performance is mainly due to the promoted rate-limiting step of C­(sp 3)–H bond activation by a chlorine radical (Cl·) from the coordinated −Cl in the MIL-101­(Fe) structure. In addition, the present photocatalyst possesses good substrate tolerance for photocatalytic selective oxidation of various toluene derivatives under optimized conditions.