A three-component Cd(II) coordination polymer for efficient multi-media iodine capture

Abstract

This work reports a simple and affordable method for synthesizing a three-component Cd(II) coordination polymer (CP) consisting of a flexible polyether-based dicarboxylate and a rigid bifunctional linker with nitrogen donor atoms for the capture of iodine from both vapor and an organic medium. A Cd(II) CP, {[Cd(toua)(4,4′-bpy)]·2H2O}n (1), was synthesized by a one pot self-assembly reaction of Cd(OAc)2·2H2O, H2toua and 4,4′-bpy in methanol at room temperature, where H2toua = 3,6,9-trioxaundecanedioic acid and 4,4′-bpy = 4,4′-bipyridine. It was characterized by elemental analysis, spectroscopic (FTIR and UV–visible spectroscopy), and microscopic techniques (SEM and TEM) techniques. 1 was found to be suitable for iodine capture both in the organic phase and vapor phase. It had significant uptakes in the vapor phase (1.78 g/g) and in hexane (623 mg/g). It also showed 100% release in ethyl acetate in 2 h, as monitored by UV–visible spectroscopy. Furthermore, the interaction of 1 and I2 was investigated by FTIR and UV–visible spectroscopy, thermogravimetric analysis, SEM and EDX analysis, and kinetic studies.