本文要点:
柔性共价有机框架(COFs)与刚性COF相比,在弹性和适应性方面具有明显优势,但这些优势往往是以结晶度为代价的,因为聚合过程中存在挑战,使合成和结构表征变得复杂。目前的研究主要采用单一的柔性单体,这限制了这些框架的可调性。
在这项研究中,作者介绍了两种高度结晶的柔性COFs,ZCST-102和ZCST-103,由双柔性单体构成。这些COFs表现出大通道、永久多孔性、高化学稳定性和优异的结晶度,以及增强的结构灵活性。值得注意的是,它们实现了高达4.71g g⁻1的碘蒸气吸附容量。
X射线光电子能谱和拉曼光谱进一步阐明了碘和骨架结构之间的相互作用。这项工作强调了引入柔性构件以保持结晶度的价值,同时赋予功能多样性,推进了动态多孔材料的设计。
Scheme 1.Strategy for preparing 2D flexible COFs with hcb net. Flexible building blocks of triangle (3-connected) knots, TFPOT (a), TAPOB (b) and TFBT (c). Extended frameworks of ZCST-102 (d) and ZCST-103 (e). (f) A hcb net for ZCST-102 and ZCST-103.
Figure 1. PXRD patterns of ZCST-102 (a) and ZCST-103 (c).AA-stacking structures of ZCST-102 (b) and ZCST-103 (d).
Figure 2. SEM images of ZCST-102 (a) and ZCST-103 (b). N2 adsorptiondesorption isotherms of ZCST-102 (c) and ZCST-103 (d).
Figure 3.Iodine uptake curves of ZCST-102 (a) and ZCST-103 (b). Iodine
release curves of ZCST-102 (c) and ZCST-103 (d).
Figure 4.XPS of I2@ZCST-102 (a) and I2@ZCST-103 (b). Raman spectra of I2@ZCST-102 (c) and I2@ZCST-103 (d). EPR spectra of (e) ZCST-102 (black curve) and I2@ZCST-102 (red curve) and (f) ZCST-103 (black curve) and I2@ZCST-103 (red curve).
https://doi.org/10.1002/asia.202401608