Ingenious Artificial Leaf Based on Covalent Organic Framework Membranes for Boosting CO2 Photoreduction

• Published in: Journal of the American Chemical Society Vol. 145; no. 17; pp. 9520 - 9529
• Main Authors: Gao, Shuaiqi, Zhang, Qian, Su, Xiaofang, Wu, Xiangkun, Zhang, Xia-Guang, Guo, Yingying, Li, Zhiyong, Wei, Jishi, Wang, Huiyong, Zhang, Suojiang, Wang, Jianji
• Format: Journal Article
• Language: English
• Published: American Chemical Society 03.05.2023
• Subjects: carbon dioxide; leaves; longevity; mass transfer; photocatalysis; photoreduction; photosensitizing agents; photosynthesis; value added
• ISSN: 0002-7863; 1520-5126; 1520-5126
• DOI: 10.1021/jacs.2c11146

Covalent organic frameworks (COFs) hold the potential in converting CO2 with water into value-added fuels and O2 to save the deteriorating ecological environment. However, reaching high yield and selectivity is a grand challenge under metal-, photosensitizer-, or sacrificial reagent-free conditions. Here, inspired by microstructures of natural leaves, we designed triazine-based COF membranes with the integration of steady light-harvesting sites, efficient catalytic center, and fast charge/mass transfer configuration to fabricate a novel artificial leaf for the first time. Significantly, a record high CO yield of 1240 μmol g–1 in a 4 h reaction, approximately 100% selectivity, and a long lifespan (at least 16 cycles) were achieved under gas–solid conditions without using any metal, photosensitizer, or sacrificial reagent. Unlike the existing knowledge, the chemical structural unit of triazine-imide-triazine and the unique physical form of the COF membrane are predominant for such a remarkable photocatalysis. This work opens a new pathway to simulating photosynthesis in leaves and may motivate relevant research in the future.