Details

Autor(en) / Beteiligte

• Liu, Yang
• Jiang, Xinyue
• Chen, Likun
• Cui, Yan
• Li, Qiu-Yan
• Zhao, Xinsheng
• Han, Xiguang
• Zheng, Yong-Chao
• Wang, Xiao-Jun

Titel

Rational design of a phenothiazine-based donor-acceptor covalent organic framework for enhanced photocatalytic oxidative coupling of amines and cyclization of thioamides

Ist Teil von

• Journal of materials chemistry. A, Materials for energy and sustainability, 2023-01, Vol.11 (3), p.128-1215

Ort / Verlag

Cambridge: Royal Society of Chemistry

Erscheinungsjahr

2023

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Owing to the high structural designability and functional tunability, covalent organic frameworks (COFs) have emerged as a promising platform for designing excellent photocatalyst candidates. However, their photocatalytic performances are still hindered by insufficient separation and transfer of photo-generated charge carriers. The ordered alignment of the electron donor (D) and acceptor (A) in two-dimensional COFs can promote charge carrier separation upon photoexcitation and provide a favorable pathway for exciton transport, and thus is advantageous for photocatalysis. In this work, we report a new D-A COF that was constructed from the electron-rich phenothiazine (PTZ) and electron-deficient triazine (TTA) subunits, giving rise to a segregated bicontinuous D-A heterostructure within the framework. In comparison to the triphenylamine (TPA) based analogue COF with smaller D-A contrast, this newly designed PTZ-TTA-COF exhibited lower exciton binding energy and enhanced charge separation/transfer. As a consequence, it revealed remarkably enhanced photocatalytic ability in oxidative amine coupling and cyclization of thioamide to 1,2,4-thiadiazole reactions under visible light and in air. This study will provide a rational guidance for developing high-performance polymeric photocatalysts based on D-A structural COFs through the molecular-level design strategy. A PTZ-based D-A COF with low exciton binding energy and high charge separation efficiency exhibited an enhanced photocatalytic performance in oxidative amine coupling and cyclization of thioamide reactions.