Ultra-highly selective trapping of perrhenate/pertechnetate by a flexible cationic coordination framework

Abstract

This work presents a 3D cationic coordination framework, showing ultra-highly selective trapping of perrhenate/pertechnetate in the presence of sulfate 20 000 times in excess.

A Highly Efficient Coordination Polymer for Selective Trapping and Sensing of Perrhenate/Pertechnetate

“…To date, several materials have been applied to immobilize or remove TcO 4 -ion from water, including anion-exchange resins, 6,7 supramolecular receptors, 8,9 crystalline inorganic cationic materials, 10 organic polymeric networks, [11][12][13][14][15][16] and coordination polymers (CPs). [17][18][19][20] Very recently, CPs showing the structural designability and diversity as well as outstanding functionalization, have been considered as promising candidates for selective anion receptors. [21][22][23][24][25][26] As for selective recognition or detection, the current common instrumental methods, such as ion chromatography, inductively coupled plasma mass spectrometry (ICP-MS), and high-performance liquid chromatography coupled with atomic absorption spectrometry, are expensive and time-consuming.…”

Anion binding in metal-organic frameworks

“…10a). TJNU-216 [37] and TJNU-302 [12] developed by Du, Zhou and coworkers are also examples of selective ReO4 − /TcO4 − adsorbent featuring trapping of ReO4 − /TcO4 − by multiple CH•••anion hydrogen bonds (Figs. 10b and 10c).…”

Selective perrhenate/pertechnetate removal by a MOF-based molecular trap

“…[13][14][15][16][17][18] Currently, employed sorbents suffer from relatively low capacity and kinetics, as well as poor selectivity to TcO 4 − . [19][20][21][22] In particular, due to its large size and low charge density, the selective removal of TcO 4 − poses a huge difficulty. In order to enhance the selectivity to TcO 4 − , some key factors to design anion-sorbents should be kept in mind.…”

“…19 (ii) To overcome the Hofmeister bias selectivity to separate TcO 4 − from anions with higher charge densities such as NO 3 − and SO 4 2− , 20 it is necessary to construct hydrophobic cationic cavities within the sorbents. 21 (iii) Incorporating soft-acidic open metal sites or potential H-bonding donors will facilitate strong interactions between the host matrix and guest TcO 4…”