Zhi Yongfeng, Wang Zongrui, Zhang Hao-Li, Zhang Qichun
School of Materials Science and Engineering Nanyang Technological University 50 Nanyang Avenue, Singapore, 639798, Singapore.
State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Tianshui South Road 222, Lanzhou, 730000, P. R. China.
Small. 2020 Jun;16(24):e2001070. doi: 10.1002/smll.202001070. Epub 2020 May 17.
Covalent organic frameworks (COFs), connecting different organic units into one system through covalent bonds, are crystalline organic porous materials with 2D or 3D networks. Compared with conventional porous materials such as inorganic zeolite, active carbon, and metal-organic frameworks, COFs are a new type of porous materials with well-designed pore structure, high surface area, outstanding stability, and easy functionalization at the molecular level, which have attracted extensive attention in various fields, such as energy storage, gas separation, sensing, photoluminescence, proton conduction, magnetic properties, drug delivery, and heterogeneous catalysis. Herein, the recent advances in metal-free COFs as a versatile platform for heterogeneous catalysis in a wide range of chemical reactions are presented and the synthetic strategy and promising catalytic applications of COF-based catalysts (including photocatalysis) are summarized. According to the types of catalytic reactions, this review is divided into the following five parts for discussion: achiral organic catalysis, chiral organic conversion, photocatalytic organic reactions, photocatalytic energy conversion (including water splitting and the reduction of carbon dioxide), and photocatalytic pollutant degradation. Furthermore, the remaining challenges and prospects of COFs as heterogeneous catalysts are also presented.
共价有机框架（COFs）通过共价键将不同的有机单元连接成一个体系，是具有二维或三维网络结构的结晶有机多孔材料。与传统多孔材料如无机沸石、活性炭和金属有机框架相比，COFs是一种新型多孔材料，具有设计良好的孔结构、高比表面积、出色的稳定性以及在分子水平上易于功能化的特点，在储能、气体分离、传感、光致发光、质子传导、磁性、药物递送和多相催化等各个领域都引起了广泛关注。在此，介绍了无金属COFs作为广泛化学反应中多相催化通用平台的最新进展，并总结了基于COF的催化剂（包括光催化）的合成策略和有前景的催化应用。根据催化反应类型，本综述分为以下五个部分进行讨论：非手性有机催化、手性有机转化、光催化有机反应、光催化能量转换（包括水分解和二氧化碳还原）以及光催化污染物降解。此外，还介绍了COFs作为多相催化剂面临的剩余挑战和前景。
