Covalent organic frameworks (COFs) are crystalline porous polymers formed by a bottom‐up approach from molecular building units having a predesigned geometry that are connected through covalent bonds. They offer positional control over their building blocks in two and three dimensions. This control enables the synthesis of rigid porous structures with a high regularity and the ability to fine‐tune the chemical and physical properties of the network. This Feature Article provides a comprehensive overview over the structures realized to date in the fast growing field of covalent organic framework development. Different synthesis strategies to meet diverse demands, such as high crystallinity, straightforward processability, or the formation of thin films are discussed. Furthermore, insights into the growing fields of COF applications, including gas storage and separations, sensing, electrochemical energy storage, and optoelectronics are provided.

中文翻译：

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共价有机框架：结构，合成和应用

共价有机骨架（COF）是一种结晶多孔聚合物，它是一种由下而上的方法，由具有预先设计的几何结构并通过共价键连接的分子构建单元形成。他们在二维和三个维度上对其构建块提供位置控制。这种控制可以合成具有高规则性的刚性多孔结构，并能够微调网络的化学和物理性质。这篇专题文章全面概述了共价有机框架开发快速发展领域中迄今为止实现的结构。讨论了满足各种需求的不同合成策略，例如高结晶度，直接的可加工性或薄膜的形成。此外，深入了解COF应用的不断发展的领域，