Deng Shu-Qi, Li Dian-Mei, Mo Xiao-Jing, Miao Yi-Ling, Cai Song-Liang, Fan Jun, Zhang Wei-Guang, Zheng Sheng-Run
School of Chemistry, South China Normal University, Guangzhou, 510006, P. R. China.
Chempluschem. 2020 Nov 24;86(5):709-715. doi: 10.1002/cplu.202000570.
Cationic amorphous metal-organic cage (MOC)-based materials capable of removing anionic pollutants from water are receiving increasing attention but they are still relatively less reported. Herein, for the first time, a cationic porous MOC-based extended framework, namely, CL-aMOC-1, was constructed by covalent linking of a cationic Pd L (L=3,5-di-pyridin-4-yl-benzaldehyde) cage with a 1,4-bis(4-aminophenyl)benzene (BAPB) linker. Interestingly, the reaction could be completed within 15 min using an amorphous MOC-based solid (aMOC-1) and BAPB as reactant via a low-temperature solid-state reaction. The CL-aMOC-1 showed improved stability, lower solubility and higher oxo-anion uptake in water compared with the original aMOC-1. The adsorption capacities for CrO , Cr O and ReO on CL-aMOC-1 were 245.1, 311.5 and 452.5 mg/g, respectively, in which the uptake of Cr(VI)-containing oxo-anions was among the highest compared with those of other metal-organic materials. The CL-aMOC-1 can selectively capture oxo-anions in the presence of competitive anions. It exhibits good reusability as over 85 % of the uptake capacity is retained after 5 cycles. Finally, it shows the ability to remove Cr(VI) ions from electroplating wastewater.
能够从水中去除阴离子污染物的基于阳离子无定形金属有机笼（MOC）的材料正受到越来越多的关注，但相关报道仍相对较少。在此，首次通过将阳离子钯配体L（L = 3,5 - 二吡啶 - 4 - 基苯甲醛）笼与1,4 - 双（4 - 氨基苯基）苯（BAPB）连接体共价连接，构建了一种基于阳离子多孔MOC的扩展框架，即CL - aMOC - 1。有趣的是，使用基于无定形MOC的固体（aMOC - 1）和BAPB作为反应物，通过低温固态反应，该反应可在15分钟内完成。与原始的aMOC - 1相比，CL - aMOC - 1表现出更高的稳定性、更低的溶解度以及在水中更高的含氧阴离子摄取量。CL - aMOC - 1对CrO 、Cr₂O₇ 和ReO 的吸附容量分别为245.1、311.5和452.5 mg/g，其中与其他金属有机材料相比，含Cr(VI)的含氧阴离子摄取量处于较高水平。CL - aMOC - 1在存在竞争性阴离子的情况下能够选择性地捕获含氧阴离子。它具有良好的可重复使用性，经过5次循环后仍保留超过85%的摄取容量。最后，它展示了从电镀废水中去除Cr(VI)离子的能力。
