Schiff base COFs for photocatalysis: From fundamentals to applications
Saira Manzoor, Muhammad Adnan Younis, Yanling Yao, Qamar‐un‐Nisa Tariq, Bing Zhang, Bingbing Tian, Liang Yan, Chuntian Qiu
Abstract
In recent times, there has been extensive exploration of Schiff base chemistry or dynamic imine chemistry for synthesis of covalent organic frameworks (COFs). Schiff base COFs are found to be very attractive for the applications in photocatalysis due to their dynamic imine chemistry and π-conjugated structures. Their extensive π-delocalization and donor-acceptor (D-A) framework enhances light absorption, charge separation, and electron transport, allowing for band gap tuning from UV to near-infrared absorption. Consequently, numerous investigations have been conducted to examine and comprehend the photocatalytic efficacy of Schiff base COFs. As a contribution, we present a comprehensive overview of recent advancements in research concerning COFs incorporating Schiff base-type linkages imine, hydrazone, azine, and β-ketoenamine or keto-enol linkages in multiple photocatalytic processes, such as organic transformation, hydrogen (H 2 ) production, carbon dioxide (CO 2 ) reduction, and pollution degradation. This review encompasses discussions on the linkage chemistry, concise synthetic methodologies, and the advantages of employing Schiff base COFs as photocatalysts, which represent a forefront area in materials science research. Additionally, the opportunities and challenges in advancing Schiff base COFs for photocatalysis and strategies to enhance their performance, aiming to inspire further research in this field are discussed.