Preparation Of Nano-ZnO And Characterization Of Its Photocatalytic Property

Nano-ZnO is a new functional semiconductor materials. As compared with common ZnO, it has unique performance, such as colouration effect, photocatalytic property, scattering and absorbing ultraviolet rays, and so on. Therefore nano- ZnO has been used more widely in wastewater treatment, sterilization, environmental protection etc. At present, people's attention focus on how to prepare nono-ZnO with low cost and energy consumption, especially uniform dispersion.In the thesis, nano-ZnO was prepared by one method combining with the structure property of ion-exchange resin and zinc sulfate as raw materials at optimal temperature and time. And it was characterized by chemical titration method, differential thermal balance, SEM, XRD, and UV-Vis spectrophotometer. Then its photocatalytic activity was evaluated.At 60 degrees centigrade water-bath and stirring 16 hours, zinc content of the product was reached 76 percent, which prepared by zinc sulfate and anion exchange resin. XRD showed that the product has good crystallization property and its purity is higher. UV-Vis property showed that the product has more strong ultraviolet absorption, and characteristic absorption peak at 360 to 400 nanometer. SEM showed that this product has good dispersivity and evenly distributed particles.The photocatalytic degradation of methyl orange solution with nano-ZnO was studied, which was prepared by ion-exchange method. Firstly, methyl orange was determined for its characteristic peaks. It has two characteristic peaks: one is at the 465 nanometer and another is at the 290 nanometer. Secondly, the optimum conditions of photocatalytic reaction: pH value is at 9, the catalyst is 300 mg/L under the solar, and 40 mg/L under the ultraviolet light. And it has systematically explained the theory of nano-ZnO photocatalysis.Then it has explored the electrochemical method that used to prepared nano-ZnO. On th condition of external electric field, nano-ZnO was directly synthesized by basic zinc carbonate. According to the settling performance of two temperature, it can be seen that the product of 60 centigrade has good dispersivity. XRD showed that the product has hexagonal structure. And this product has bactericidal effect.