Sensitivity to NH3 Vapor: Synthesis and Characterization of Five New Coordination Polymers Based on 2,2-Dimethylglutaric Acid and Bis(triazole)-Derived Ligands

Five new coordination polymers (CPs) were obtained as a result of hydrothermal reactions of 2,2-dimethylglutaric acid (H2dmg) and 1,4-bis(1H-1,2,4-triazol-1-ylmethyl)benzene (pbtx)/1,2-bis(1H-1,2,4-triazol-1-ylmethyl)benzene (obtx) ligands with some metal ions [Co(μ-dmg)(μ-obtx)]n (1), [Zn(μ-dmg)(μ-obtx)]n (2), [Cd(μ-dmg)(μ-obtx)]n (3), [Co2(μ-dmg)2(μ-pbtx)2]n (4), and [Cd(μ-dmg)(H2O)(μ-pbtx)]n (5). All of the compounds were characterized by elemental analysis, FT-IR spectroscopy, single-crystal X-ray diffraction, powder X-ray diffraction, and thermal analysis techniques. The single-crystal X-ray studies show that all compounds exhibit 2D layer structures. To examine the ammonia sensing properties of five new coordination complexes (1-5), the absorption and emission spectra of CPs embedded in ethyl cellulose thin films were measured by exposure to different concentrations of ammonia (NH3) vapor. The [Co2(μ-dmg)2(μ-pbtx)2]n (4)-based sensor agent was found to show promising sensor properties in detecting NH3 vapor.

An inorganic-organic hybrid nanomaterial with a core-shell structure constructed by using Mn-BTC and Ag5[BW12O40] for supercapacitors and photocatalytic dye degradation

Creating inorganic-organic hybrids with polyoxometalates (POMs) and metal-organic frameworks (MOFs) as energy storage and dye-degradation materials remains challenging. Here, a new hybrid nanomaterial Mn-BTC@Ag₅[BW₁₂O₄₀] is synthesized by using Ag₅[BW₁₂O₄₀] and Mn₃(BTC)₂(H₂O)₆ (Mn-BTC, BTC = 1,3,5-benzenetricarboxylic acid) through a plain grinding method. The structure and morphology characterization by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), and transmission electron microscopy (TEM) shows that the synthetic products have core-shell construction. Due to its unique structure wherein the core is Mn-BTC and the shell is Ag₅[BW₁₂O₄₀], it exhibits excellent capacitance performance. In a three-electrode system where nickel foam is a collector, at a current density of 1 A g^-1, its specific capacitance is 198.09 F g^-1; after 5000 cycles, the capacitance retention rate is 94.4%. When the power density is 503.1 W kg^-1, the symmetrical supercapacitor reveals a high energy density which is 10.9 W h kg^-1. At the same time, the capacitance retention is 92.9% after 5000 cycles which showed good cycle stability. The photocatalytic degradation efficiencies of rhodamine B (RhB), methyl orange (MO) and methylene blue (MB) dyes exceed 90% after 140 min, and the degradation results remained unchanged after five photocatalytic cycles. The photocatalytic degradation mechanism shows that ˙OH has a major effect. The results show that this research provides a fresh idea for the development of energy storage and dye photocatalytic degradation materials.

Two unusual 3D honeycomb networks based on Wells–Dawson arsenomolybdates with d10 transition-metal-pyrazole connectors

Two unusual 3D honeycomb networks based on Wells–Dawson arsenomolybdates were first reported, which have highly efficient catalytic ability for the degradation of organic dyes under UV irradiation and obvious electrocatalytic activities for the reduction of H₂O₂.

A 3D cadmium–vanadium bimetallic framework with luminescence properties

Luminescent properties of a novel cadmium–vanadium bimetallic 3D framework possessing a pillared-layer.