Effective degradation of tetracycline by organic-inorganic hybrid materials induced by triethylenediamine.

As an important advanced oxidation technology for environmental purification, photocatalytic degradation has received extensive attention. Designing and synthesizing a catalyst with high-intensity photocatalytic performance is a very challenging subject. Herein, one polydentate cation was synthesized by 1,4-diazabicyclo[2.2.2]octane (DABCO) and 1, 4-bis (bromomethyl) benzene. Inorganic-organic hybrid compounds 1, 2 were synthesized by hydrothermal and room temperature volatilization with inorganic metal salts, namely, {[L1]0.5·[Cu2Br4]0.5}n (1), {[L1]·[Cu2I4]·CH3CN}n (2). Under visible light, compounds 1 and 2 were investigated for their degradation effects on tetracycline (TC) in water. The experimental results showed that compounds 1 and 2 with appropriate concentration of H2O2 had obvious photocatalytic degradation effect on TC. In addition, the influencing factors of photocatalysis such as the amount of adsorbent, the initial concentration of TC and the different pH value were investigated. The photocatalyst exhibits good stability and cyclability.

Preparation of 2D supramolecular material doping with TiO2 for degradation of tetracycline.

Anatase TiO2 photocatalyst supported on [BMPP]2[2D-Mo18O56] (BMPP = 1, 3-bis(4-methylpyridine) propane dibromide) was successfully prepared by hydrothermal method. The composites were characterized by field emission scanning electron microscopy (SEM), X-ray diffractometer (XRD), infrared spectroscopy (IR) and energy-dispersive X-ray spectrometer (EDS). The results show that the high content anatase nanoparticles are uniformly loaded on the polyacid supramolecules to form the composite material. The photocatalytic activity of TiO2/Mo9O28-BMPP towards the tetracyclines (TCs), a model pollutant, has been investigated. The results show that under a 500W high-pressure xenon lamp, 0.15 g TiO2/MoB can degrade 97% of 20 mL (25 mg/L) Tc after 115 min, showing high catalytic activity. In addition, 0.15-TiO2/MoB can be easily separated from the reaction system by centrifugation, and the catalyst still maintains high photocatalytic activity after 3 cycles of tests under the same conditions. This shows that it has the potential for recycling. This research provides a new way for the development of new supported catalysts.

Two Nanometer-Sized High-Nuclearity Homometallic Bromide Clusters (M26Br38)12- (M = Cu, Ag): Syntheses, Crystal Structures, and Efficient Adsorption Properties.

The spontaneous formation of discrete spherical nanosized molecules is ubiquitous in nature; however, the actual structural imitation of such high-symmetry polyhedra from the edge sharing of regular polygons has still proved to be elusive. Herein, two high-nuclearity metal clusters, namely (TTB)4·M26Br38 (M = Cu (1), Ag (2), TTB·Br3 = 1, 3, 5-tris(triethylammoniomethyl)benzene tribromide), have been rationally and solvothermally synthesized and structurally characterized. Single-crystal X-ray analysis confirmed that 1 has I4̅3m symmetry with a (Cu25Br34)12- anion shell enwrapping a CuBr4 tetrahedron and 2 has I4̅3m symmetry with a [Ag26Br34]12- anion shell enwrapping a Br4 pyramid. The diffuse-reflectance UV-vis measurements showed that both compounds possess proper semiconductor behaviors with tunable band gaps of 1.87 eV for 1 and 1.90 eV for 2. Interestingly, all the samples feature distinct adsorption speed and compound 1 shows good adsorption activity for methyl orange (MO) under the same reaction conditions. The effects of pH, temperature, and cyclicity on dye adsorption, together with the thermal stabilities and luminescence properties of the compounds, were also studied. From the cyclic adsorption of compound 1 to the anionic dye MO, it was found that the adsorption of MO was good over three cycles, and the third adsorption rate was still 93.90%.