We herein develop a two-in-one molecular design strategy for facile synthesis of 2D imine based covalent organic frameworks (COFs). The integration of two different functional groups (i.e. formyl and amino groups) in one simple pyrene molecule affords a bifunctional building block: 1,6-bis(4-formylphenyl)-3,8-bis(4-aminophenyl)pyrene (BFBAPy). Highly crystalline and porous Py-COFs can be easily prepared by the self-condensation of BFBAPy in various solvents, such as CH2Cl2, CHCl3, tetrahydrofuran, methanol, ethanol, acetonitrile, and dimethylacetamide, etc. The current work, to the best of our knowledge, is a rare case of COF synthesis that exhibits excellent solvent adaptability. Highly crystalline Py-COF thin films have been facilely fabricated on various substrates and exhibit potential applications in hole transporting layers for perovskite solar cells. Furthermore, the versatility of this two-in-one strategy was also verified by two additional examples. The current work dramatically reduces the difficulty of COF synthesis, and such two-in-one strategy is anticipated to be applicable for the synthesis of other COFs constructed by different building blocks and linkages.

中文翻译：

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二维共价有机框架的从头设计和简便合成：二合一策略

我们在此开发了一种二合一分子设计策略，用于轻松合成基于 2D 亚胺的共价有机框架 (COF)。两个不同的官能团（即甲酰基和氨基）在一个简单的芘分子中的整合提供了一个双功能结构单元：1,6-双（4-甲酰基苯基）-3,8-双（4-氨基苯基）芘（BFBAPy） . 通过 BFBAPy 在各种溶剂（如 CH2Cl2、CHCl3、四氢呋喃、甲醇、乙醇、乙腈和二甲基乙酰胺等）中的自缩合，可以很容易地制备出高度结晶和多孔的 Py-COF。知识，是 COF 合成的罕见案例，具有出色的溶剂适应性。高度结晶的 Py-COF 薄膜已在各种基板上轻松制造，并在钙钛矿太阳能电池的空穴传输层中显示出潜在的应用。此外，另外两个例子也验证了这种二合一策略的多功能性。目前的工作极大地降低了COF合成的难度，这种二合一策略有望适用于由不同构建块和链接构建的其他COF的合成。