本文要点：
在拓扑图的指导下，可以合成具有可设计孔结构的二维(2D)共价有机框架。在现有的五种边传递拓扑网中，kgd拓扑被认为是构造超微孔COFs的良好候选。然而，所有报道的具有kgd拓扑结构的COFs都需要使用C6对称的单体，这在化合物类型上受到限制并且难以合成。
在这里，作者首先发展了一种新的方法来构建2D COFs (clv-COFs ),其具有与kgd拓扑相似的几何形状，命名为kgd-v拓扑，通过C2v-和C3-对称单体的组合。
这些clv-COFs 中微孔的尺寸与kgd拓扑中的菱形孔一致，并且可以通过改变C2v-和C3-对称单体的长度来容易地调节。由于规则的小微孔，这些clv-COFs 表现出优异的大气水收集(AWH)能力。
基于clv-COF-1的高效采水器在太阳光照下，相对湿度为45%时，每天可生产1.73 L kg-1。作者的方法丰富了网状化学，可以促进基于COF的AWH系统的研究。
Figure 1. Topological diagrams of kgd and kgd-v topologies (a) and the development of pore shapes in 2D COFs where the vertices are connected by one kind of edge (b).
Figure 2. Schematic synthesis route to clv-COFs.
Figure 3. Views of the unit cell along the z-axis derived from eclipsed AA-stacking models of clv-COF-1 (a) and clv-COF-2 (b). Experimental PXRD patterns, Pawley refined PXRD patterns, their differences, predicted PXRD patterns using the eclipsed AA-stacking, and Bragg positions of clv-COF-1 (c) and clv-COF-2 (d). Nitrogen adsorption–desorption isotherms of clv-COF-1 (e) and clv-COF-2 (f).
Figure 4. SAD image (a) and HRTEM images (b, c) of clv-COF-1. SAD image (d) and HRTEM images (e, f) of clv-COF-2.
Figure 5. (a) Dynamic vapor sorption curves of clv-COF-1 and clv-COF-2 at 298.15 K. (b) The adsorption kinetics curves of clv-COFs at RH = 50%. The adsorption and desorption processes are carried out at 298.15 and 333.15 K, respectively. (c) The schematic illustration of AWH devices. (d) Per cycle and cumulative water amounts collected by AWH device. (e, f) The photographs of AWH devices with condensed water drops.
https://doi.org/10.1021/jacs.4c12973
