本文要点：
具有离子特性和高共轭结构的离子型乙烯键共价有机框架是一种很有前途的功能材料。然而，报道的离子亚乙烯基连接的COFs的数量及其合成方法仍然有限。
本文首次采用新型仿生界面水热合成法合成了两种新型的离子型亚乙烯基共价有机骨架(命名为COF-NUC-1和COF-NUC-2)。
由于共轭醛单体在水中的不溶性，产生了分子/水界面，其中水溶性的N-乙基-2，4，6-三甲基吡啶鎓溴化物(ETMP-Br)可以通过界面限制的Knoevenagel缩合反应与醛单体反应。
所得离子COFs显示出高结晶度、高化学稳定性和亲水性。得益于吡啶盐的吸电子和氧化还原性质，基于COF-NUC-1薄膜的忆阻器表现出稳定的非易失性记忆效应，具有0.66 × 103的高开关电流比和0.68 V的小开启电压。这项工作扩展了ivCOFs的领域，加深了对水热合成的理解。
Figure 1. Interfacial hydrothermal synthesis of the ionic vinylene-linked covalent organic framework.
Figure 2. a) PXRD patterns of COF-NUC-1. b) Top and side views of the eclipsed AA-stacking model of COF-NUC-1. c) PXRD patterns of COF-NUC-2. d) Top and side views of the eclipsed AA-stacking model of COF-NUC-2. e) The N 1s core level XPS spectra of COF-NUC-1 and COF-NUC-2. f) The pore size distribution profiles of COF-NUC-1 and COF-NUC-2.
Figure 3. Field-emission scanning electron microscopy image of COF-NUC-1 (a) and COF-NUC-2 (b). HRTEM image of COF-NUC-1 (c) and COF-NUC-2 (d).
Figure 4. PXRD patterns a) and residual weight percentages b) of COF-NUC-1 after treatment in aqueous HCl solution (1 m), aqueous NaOH solution (1 m), DMF, or DCM for 2 days. PXRD patterns c) and residual weight percentages d) of COF-NUC-2 after treatment in aqueous HCl solution (0.1 m), aqueous NaOH solution (1 m), DMF, or DCM for 2 days.
Figure 5. The memristive measurements of COF-NUC-1. a) Schematic diagram of the memristor device. b) I–V curves. c) Stability of the device currents in both ON and OFF states. g) Switching stability at a read voltage of 0.1 V. e) Histogram of the distribution of VSET and VRESET. f) Cumulative probability (CP) plot.
Figure 6. The optical and electronic properties of COF-NUC-1. a) UV/vis diffuse reflectance spectra. b) (??h??)2 versus h?? curve. c) UPS spectrum. d) Energy levels. e) Electrostatic potential distributions. f) Calculated density of states.
https://doi.org/10.1002/smll.202409233
