Preparation Of Visible Light Responsive Materials And Their Environmental Application

Nowadays, People are concerned about the survival of the environment increasingly. Industrial development gets economic development of the country moving.It is undeniable, it also brings different levels of water pollution. Industrial wastewater are composed of numerous chemicals, and it is hard to process.Understanding degradation and detection of each component is very helpful for wasterwater processing. Rhodamine B is an ordinary dye, it gets a wide range of application in the industry due to its numerous advantages. Rhodamine B without processing not only caused water pollution, but also harm and even kill over a long period of time. In order to reduce waste pollution that is caused by Rhodamine B on the water environment, it is necessary to understand the degradation process. If some heavy metal ions in water can be detected with a fast and convenient way, it can greatly reduce the processing time for the entire wastewater. Degradation pathways of rhodamine B and quantum dots rapid detect of copper ions have been studied In this thesis, mainly as follows:(1) Porous BiVO4was prepared by using impregnation method, bisumuth nitrate pentahydrate and ammonium metavanadate as materials, and the KIT-6template as template. Samples were characterized by each instrument. The XRD patterns of nonporous BiVO4and porous BiVO4consistent with the standard card, they are the same substance, both of their crystalline are monoclinic scheelite. One sample has ordered pore structure, because two distinct diffraction peaks appear in the small-angle XRD pattern of it. Both sample have light absorption in the visible region, compared to non-porous BiVO4, porous BiVO4has wide range of light absorption and strong light absorption. band gap of porous BiVO4is smaller. It can be seen clearly on TEM photographs, Porous BiVO4holes are arranged in order, surface area、pore volume、pore size of the porous BiVO4are calculated by date that is measured by nitrogen adsorption-desorption. Rhodamine B is degraded by nonporous BiVO4and porous BiVO4. The photocatalytic effect of porous BiVO4is better. Both degradation of UV-visible figure, the maximum absorption wavelength of Rhodamine B redshifts in varying degrees.Further analyzing their intermediate product and mass thing on the spectrometry, products of two degradation systems are mainly de-ethylation product. it described that they have same degradation pathway.(2) CdTe was prepared using the hydrothermal strategy, Tellurium powder、Sodium borohydride、Cadmium chloride as material,and as TGA Modifier. quantum dots were prepared by different hydrothermal time that is3h、5h、7h、9h、12h. With hydrothermal time increasing, the first absorption peak of quantum dots move towards longer wavelength gradually.It Shows that the particle size grew up. fluorescence emission peak is symmetrical and its position redshift slowly.It can be seen that particle size of quantum dots is uniformitarian.we can observe from TEM photographs, quantum dots is serious agglomeration because of poor dispersion of water-soluble, polystyrene photonic crystals was prepared by the vertical method,280nm polystyrene beads as material. Its photonic bandgap is570nm. emission wavelength of quantum dot with9h Hydrothermal Preparation time match it.they combine together with electrostatic adsorption. conductive glass quantum dot systems and photonic crystal quantum dot system are prepared. photonic crystals of Bragg diffraction enhance quantum dot’s fluorescence intensity. fluorescence intensity of Photonic crystal quantum dot system is higher than conductive glass quantum dot system. two systems use as a probe measuring copper ion0.2nm/L-lnm/L. Two systems have a better response to copper ions, with the increase of the copper ion concentration, the fluorescence intensity decreases. standard curve draw After detection, the regression equation was Y=-0.554+13.497*X, the linear correlation coefficient was R=0.961, The detection limit is0.019μmol/L in Photonic crystal quantum dot system. The regression equation was Y=0.951+0.00423*X, the linear correlation coefficient was R=0.989, The detection limit was0.04μmol/L in Conductive glass quantum dot system.