In this study the preparation and characterization of a zinc MOF which gives blue luminescence and photocatalytic activity have been described The reaction of 2cyanopyridine, Zn(NO 3) 2 •4H 2 O and NaN 3 yielded a new 3D Zn(II) coordination polymer {(2PTZ) 2 Zn} n (1), where 2PTZ=5(2pyridyl)tetrazolate via in situ [2+3] cycloaddition reaction of the nitrile and the azide. Compound 1 was characterized by elemental analyses, IR spectroscopy, X-ray powder diffraction (XRPD), scanning electron microscopy (SEM) and singlecrystal X-ray crystallography. Crystal structure of the compound belongs to monoclinic space group C2/c with Z = 2I n1 the crosslinkage of the PTZ ligands and Zn(II) atoms forms an infinite 1D chain network. Further the one-dimensional chains are assembled into threedimensional network by hydrogen bonding. Thermal photoluminescence and photocatalytic properties of 1 were also been investigated.

The paper describes the experiments conducted to create shape controllable preparations of submicronic cadmium tetrazole‐based MOFs. In order to prepare the submicron sized blocks and tubes of bis[5‐(2‐pyridyltetrazolato)]diaquacadmium(II) [(2‐PTZ)2Cd(H2O)2] MOFs both solvothermal and microwave augmented reaction procedures have been followed. Cadmium nitrate tetrahydrate, cyanopyridine and sodium azide were used as reactants in both the conditions without any surfactants or modulators. Subsequently, IR spectroscopy and single‐crystal X‐ray crystallographic studies were performed on the prepared MOFs. Examinations using scanning electron microscopy and X‐ray powder diffraction of the products made by the microwave method showed formation of bundles of regular submicrotubes, as opposed to the submicron‐sized irregular blocks of the Cd‐MOF obtained through the solvothermal method. The fluorescence peak of the sub‐microtube MOF was found at 460 nm while the irregular‐blocks emitted at 442 nm indicating a red shift for the former. In addition, the relative intensity of the peak at 460 nm was higher in the former, indicating a decrease in the crystallite size. Band gaps of the MOFs calculated by using the Tauc plots were 2.87 and 2.73 eV, respectively. Their photocatalytic performances using methylene blue under UV‐vis irradiation have been investigated.

A copper‐based metal‐organic framework (MOF) Bis[5‐(2‐pyridyl)tetrazolato]diaquacopper(II) [{CuP}n], has been designed and structurally characterized by single‐crystal X‐ray crystallography. The three‐dimensional crystal structure belongs to the monoclinic space group P21/c with Z=4. Further a series of isostructural complexes [{Cu1‐xZnxP}n] (x=1, 0.75, 0.5, 0.25, 0), {P=(5‐(2‐pyridyl)tetrazolato)2.2H2O} have been synthesized via a facile one‐pot microwave irradiated solvothermal method. The optical and photocatalytic properties of the synthesized bimetallic complexes were investigated and compared with those of monometallic complexes. The effects of metal substitutions in the ligand backbone were investigated. A striking variation in the bandgap i. e., from 4.1 eV (x=1) to 2.79 eV (x=0) was observed among the catalysts with a minimum value of 1.93 eV (x=0.25). The optimized catalyst Cu0.75Zn0.25P exhibits the highest degradation activity and reached up to 99 % for RhB (rhodamine B) and 96 % for MB (methylene blue) in 120 min of Sunlight, corresponding to the respective photocatalytic degradation rates of 0.0328 min−1 and 0.0301 min−1. The kinetics of the degradation processes were best statistically described by pseudo‐first‐order. The catalyst was also found to have sufficient stability and recyclability with promising applications in removal of organic dye pollutants.

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