|
|||||
|
|
Modulating Benzothiadiazole-Based Covalent Organic Frameworks via Halogenation for Enhanced Photocatalytic Water Splitting |
|
| Authors: | Weiben Chen Lei Wang Daize Mo Prof Feng He Zhilin Wen Prof Xiaojun Wu Prof Hangxun Xu Prof Long Chen |
| Institution: | 1. Department of Chemistry, Institute of Molecular Plus, Tianjin Key Laboratory of Molecular Optoelectronic Science, Tianjin University, Tianjin, 300072 P. R. China
These authors contributed equally to this work.;2. Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui, 230026 China These authors contributed equally to this work.;3. Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055 China;4. Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui, 230026 China;5. Department of Chemistry, Institute of Molecular Plus, Tianjin Key Laboratory of Molecular Optoelectronic Science, Tianjin University, Tianjin, 300072 P. R. China |
| Abstract: | Two-dimensional covalent organic frameworks (2D COFs), an emerging class of crystalline porous polymers, have been recognized as a new platform for efficient solar-to-hydrogen energy conversion owing to their pre-designable structures and tailor-made functions. Herein, we demonstrate that slight modulation of the chemical structure of a typical photoactive 2D COF (Py-HTP-BT-COF) via chlorination (Py-ClTP-BT-COF) and fluorination (Py-FTP-BT-COF) can lead to dramatically enhanced photocatalytic H2 evolution rates (HER=177.50 μmol h?1 with a high apparent quantum efficiency (AQE) of 8.45 % for Py-ClTP-BT-COF). Halogen modulation at the photoactive benzothiadiazole moiety can efficiently suppress charge recombination and significantly reduce the energy barrier associated with the formation of H intermediate species (H*) on polymer surface. Our findings provide new prospects toward design and synthesis of highly active organic photocatalysts toward solar-to-chemical energy conversion. |
| Keywords: | charge transfer covalent organic frameworks halogenation photocatalytic water splitting solar energy conversion |