Catalytic Application of Tactically Aligned Cd(II)-Based Luminescent 3D-Supramolecular Networks

Abstract

A new Cd(II) based coordination polymers {[Cd(Azopy)(H2O)4]⋅(NDC)}n (1) has been designed and synthesized by using 4,4′-Azopyridine (Azopy), and 2, 6-Naphthalene dicarboxylic acid (NDC) as a linker at ambient condition. The bulk purity of the 1 was analysed by powder X-ray diffraction (PXRD) analysis, infrared spectroscopy and further confirmed by single crystal X-ray studies. The crystal structure of 1 revealed a polythreading feature where each 2, 6-naphthalene dicarboxylate unit are trapped between two one-dimensional (1D) chain of [Cd(Azopy)(H2O)4]∞ via strong hydrogen bonding interactions. The hydrogen bonding and π⋅⋅⋅π stacking interactions of 1 play a crucial role in the formation of the infinite 3D-layered supramolecular network. Furthermore, the reduction of nitro-aromatics to their corresponding amines was performed using green hydrogen source such as D-glucose in H2O solvent at room temperature. Additionally, the dye adsorption studies revealed that 1 can adsorb Congo Red (CR) dye in a very short span of time. The kinetic study result reveals that the adsorption of CR for 1 is fitted well (R2 =0.996) with a pseudo-second-order kinetic model. Moreover, photoluminescence of 1 shows emission in the blue region with λmax at 395 nm and 408 nm at room temperature in the solid state. 1 shows multi-facet behaviour such as facile synthesis, luminescent nature in solids-state, emerged as a heterogeneous dye-adsorbent and catalyst which makes it easy to scaled-up. © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim