Three Silver(I) Coordination Polymers Based on Pyridyl Ligands and Auxiliary Carboxylic Ligands: Luminescence and Efficient Sensing Properties

Abstract

Easily producible sensors for harmful industrial waste compounds are of significant interest for both human health and the environment. Three novel coordination polymers, [Ag(μ-aca)(μ 4 -bztpy) 1/2 ] (1), [Ag(μ-bza)(μ-bpa)] (2), and [Ag 2 (μ-aca) 2 (μ-bpa) 2 ]•EtOH•2H 2 O (3), were assembled in this study by reactions using Ag + as a node with the pyridyl ligand 1,2,4,5-tetrakis(4pyridyl)benzene (bztpy) or 9,10-bis(4-pyridyl)anthracene (bpa) and an auxiliary chelating carboxylic ligand. Single-crystal X-ray structural analyses revealed that compound 1 has a 3D framework consisting of 1D [Ag(aca)] ∞ chains and bztpy linkers, while 2 and 3 have 2D layered structures consisting of binuclear Ag− carboxylate units and bpa linkers, respectively. Topological studies revealed that 1 has a bbf topology, while 2 and 3 are 2D [4,4] rhombic grids. The compounds were further characterized by powder X-ray diffraction, IR, elemental analysis, thermogravimetric analysis, and a luminescence study. The solids of 1−3 exhibited intense photoluminescent emission with λ em max at ca. 493, 472, and 500 nm, respectively. Remarkably, due to their excellent framework stability, 1 and 2 can act as multiresponsive luminescent sensors for nitrobenzene, Fe 3+ , and Cr 2 O 7 2− with a high selectivity and sensitivity ascribed to their quenching effect.

Design and synthesis of new luminescent coordination networks of sql topology showing the highest degrees of interpenetration

“…However, coordination networks showing, in contrast, a blue-shift of these maxima are well documented in the literature. [68][69][70] In these cases, the observed blue shift induced by metal coordination can be attributed to a higher rigidity of the ligand constrained in the network that prevents the π-π* excited state from reaching an optimal (typically more planar) conformation. The different blue-shift observed for 1 and 2 is in agreement with this interpretation.…”

Five Novel Silver‐Based Coordination Polymers as Photoluminescent Sensing Platforms for the Detection of Nitrobenzene

“…The reticular construction of silver coordination polymers (Ag x -CPs) [17][18][19][20][21][22][23] with metal-linker coordination bonds could resolve this stability issue for which the Ag-CP based sensors for NB have gained prominence. [24][25][26] In this work, we exercised the diverse coordination geometries of silver ion/cluster-based nodes with intricately designed organic linkers to present five newly synthesized silver-based coordination polymers, Ag x -CPs, where x denotes the number of Ag atoms constituting the inorganic nodes of the CPs (x = 1, 10, 12). By virtue of the π À π stacking interactions between the polymers and NB as well as the electron-withdrawing character of NB, the Ag x -CPs exhibited significant fluorescence quenching behavior with NB.…”

Room-temperature synthesis of nanometric and luminescent silver-MOFs

“…Several Ag-coordinated polymers have shown luminescence capabilities, some of them reported years ago (Ding et al, 2005); however, their emissive behavior is not well understood, with some cases showing ligand-to-metal energy transfer (through bonds) and others showing antenna effects (through space). Moreover, their emissive contributions "turn on" or vary due to particular structural arrangements between ligands, for e.g., carboxylate coordination modes, toward the Ag centers, and the number of Ag atoms in the coordinating net, but also due to the number and positions of carboxylate moieties in the linker, with emissive examples of two, three, four, or even six carboxylate moieties in the ligand (Sun et al, 2014;Xia et al, 2018;Gutiérrez et al, 2020;Yu et al, 2020;Chen et al, 2021;Mackenzie et al, 2021).…”