Covalent organic frameworks (COFs) are the emerging type of organic crystalline porous materials, prepared through reticular chemistry with building blocks featuring light elements (such as C, H, O, N, or B atoms), and connected through the covalent bond and extended into two or three dimensions. In the past few years, COFs have attracted attention for their interesting properties, including high-order porosity, structural versatility, facile surface modification, and high thermal and chemical stabilities. Accordingly, COFs are potential platforms for diverse practical implementations, including gas separation and storage, heterogeneous catalysis, chemical sensing, luminescence, electronic devices, drug delivery, and energy storage and conversion. This Review provides the overview of the design strategies and synthetic methodologies that have been used widely for the preparation of COFs, and also summarizes selected examples of their applications.

共价有机骨架（COF）是新兴的有机晶体多孔材料，它是通过网状化学方法制备的，具有以轻元素（例如C，H，O，N或B原子）为基础的结构单元，并通过共价键连接并延伸分为两个或三个维度。在过去的几年中，COF的有趣特性吸引了人们的注意，这些特性包括高阶孔隙率，结构通用性，易于表面改性以及高热稳定性和化学稳定性。因此，COF是用于各种实际实现的潜在平台，包括气体分离和存储，非均相催化，化学传感，发光，电子设备，药物输送以及能量存储和转换。