Two novel d10 metal coordination polymers based on an asymmetric polycarboxylate ligand: Synthesis, crystal structure, photoluminescence and photocatalysis

Abstract

abstract Two novel coordination polymers (CPs), [Cd2(cbta)(phen)2(H2O)]n (1), {[Zn2(cbta)(phen)2] [Zn2(cbta) (phen)2(H2O)]·4H2O}n (2) (H4cbta = 1-(2-carboxylphenoxy)-2,3,5-benzene tricarboxylic acid; phen = 1,10-phenanthroline), were synthesized and characterized by elemental analyses, FT-IR spectra, single-crystal X-ray diffraction analyses. CP 1 shows a 2D network structure based on tetranuclear CdII clusters and (cbta)4- ligands, which are arranged in a [ABAB···] alternation to form a 3D supramolecular structures through π···π stacking interactions. Noticeably, CP 2 contains two kinds of independent units [Zn2(cbta)(phen)2] (A) and [Zn2(cbta)(phen)2(H2O)]·4H2O (B) to form a 1D+1D structure. A shows 1D double chain based on Zn1, Zn2, which are recognized each other to generate a 2D supramolecular network (A) by hydrogen bonding interactions. While B are ring chains comprised of Zn3, Zn4, which are linked into 2D supramolecular network (B) through π···π stacking interactions. The peculiar structural feature is that the neighboring 2D networks are arranged in a [ABAB···] alternation to form a 3D supramolecular structure through hydrogen bonding interactions and C H···π and C H⋯O week interactions. Especially the (ctba)4- ligands in 1–2 adopt three different conformations and coordination modes. The thermal stabilities, XRD, UV, photoluminescence properties of CPs 1–2 were also studied. Remarkably, CPs 1–2 exhibit photocatalytic activities for degradation of dye (MB) under UV light irradiation and show good stabilities toward UV-light photocatalysis.