In the light of increasing energy demand and environmental pollution, it is urgently required to find a clean and renewable energy source. In these years, photocatalysis that uses solar energy for either fuel production, such as hydrogen evolution and hydrocarbon production, or environmental pollutant degradation, has shown great potential to achieve this goal. Among the various photocatalysts, covalent organic frameworks (COFs) are very attractive due to their excellent structural regularity, robust framework, inherent porosity and good activity. Thus, many studies have been carried out to investigate the photocatalytic performance of COFs and COF-based photocatalysts. In this critical review, the recent progress and advances of COF photocatalysts are thoroughly presented. Furthermore, diverse linkers between COF building blocks such as boron-containing connections and nitrogen-containing connections are summarised and compared. The morphologies of COFs and several commonly used strategies pertaining to photocatalytic activity are also discussed. Following this, the applications of COF-based photocatalysts are detailed including photocatalytic hydrogen evolution, CO₂ conversion and degradation of environmental contaminants. Finally, a summary and perspective on the opportunities and challenges for the future development of COF and COF-based photocatalysts are given.

中文翻译：

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共价有机骨架光催化剂：结构和应用。

鉴于不断增长的能源需求和环境污染，迫切需要找到一种清洁和可再生的能源。近年来，将太阳能用于燃料生产（如氢气生成和碳氢化合物生产）或环境污染物降解的光催化作用显示出了实现这一目标的巨大潜力。在各种光催化剂中，共价有机骨架（COF）具有出色的结构规则性，坚固的骨架，固有的孔隙率和良好的活性，因此非常具有吸引力。因此，已经进行了许多研究来研究COF和基于COF的光催化剂的光催化性能。在这篇重要的评论中，将全面介绍COF光催化剂的最新进展。此外，总结并比较了COF构件之间的各种连接基，例如含硼连接和含氮连接。还讨论了COF的形态以及与光催化活性有关的几种常用策略。在此之后，详细介绍了基于COF的光催化剂的应用，包括光催化制氢，CO₂环境污染物的转化和降解。最后，总结并展望了COF和COF基光催化剂未来发展的机遇与挑战。