Allahyarli Kamal, Reithofer Michael R, Cheng Fei, Young Adam J, Kiss Endre, Tan Tristan Tsai Yuan, Prado-Roller Alexander, Chin Jia Min
Faculty of Chemistry, Institute of Physical Chemistry, University of Vienna, Währingerstr. 42, Vienna A-1090, Austria.
Faculty of Chemistry, Department of Inorganic Chemistry, University of Vienna, Währingerstr. 42, Vienna A-1090, Austria.
J Colloid Interface Sci. 2022 Mar 15;610:1027-1034. doi: 10.1016/j.jcis.2021.11.151. Epub 2021 Nov 27.
Most MOFs are non-cubic, with functionality dependent upon crystallographic direction, and are largely prepared as microcrystalline powders. Therefore, general methods to orient and assemble free-standing MOF crystals are especially important and urgently needed. This is addressed here through the novel strategy of E-field assisted liquid crystal assembly, applied to MIL-53-NH(Al), MIL-68(In) and NU-1000 MOF crystals, with aspect ratios ranging from 10 to 1.2, to form highly oriented MOF superstructures which were photopolymerized to fix their long-ranged order. This new strategy for controlling MOF orientation and packing side-steps the traditional requirements of particle monodispersity, shape homogeneity and high aspect ratios (>4.7) typical of colloidal and liquid crystal assembly, and is applicable even to polydispersed MOF crystals, thereby paving the way towards the development of highly oriented MOF composites with improved functionality.
大多数金属有机框架材料（MOF）不是立方晶系，其功能取决于晶体学方向，并且大多制备成微晶粉末。因此，使独立的MOF晶体定向和组装的通用方法尤为重要且迫切需要。本文通过电场辅助液晶组装的新策略解决了这一问题，该策略应用于长径比在10至1.2范围内的MIL-53-NH(Al)、MIL-68(In)和NU-1000 MOF晶体，以形成高度定向的MOF超结构，这些超结构通过光聚合固定其长程有序结构。这种控制MOF取向和堆积的新策略避开了传统的胶体和液晶组装中对颗粒单分散性、形状均匀性以及高长径比（>4.7）的要求，甚至适用于多分散的MOF晶体，从而为开发具有改进功能的高度定向MOF复合材料铺平了道路。
