The Research Of The Preparation Of Zinc Oxide Photocatalyst And The Degradation Of Reactive Brilliant Blue

Zinc oxide (ZnO) is one of the most important direct bandgap N-semiconductor materialbecause of its superior photocatalytic performance, relatively low cost, non-toxic andenvironmental friendliness. However, the fast recombination of photoexcited electrons andholes, the inefficient use of sunlight of ZnO and low photocatalytic activity restrict thedevelopment in photocatalytic degradation of dye wastewater. To solve this problem, ZnO asthe research target was prepared through changing the morphology of ZnO and doping withmetal and nonmetal elements. To evaluate the photocatalytic ability of the composite catalyst,the photodegradation of reactive brilliant bule (KN-R) dye wastewater under UV lightirradiation was carried out. The specific research contents are as follows:(1) The preparation and photocatalytic performance of ZnO composite photocatalyst.Zinc powder as raw materials, urchin-like ZnO composite photocatalysts were fabricatedby hydrothermal method. It was investigated for utilizing hydrothermal time to control themorphology and photoelectric properties of ZnO. The highest photocatalytic activity of theas-obtained ZnO can be achieved under UV light irradiation when the hydrothermaltemperature is180℃and the hydrothermal time is120min, the phtodegradation rate forKN-R was83.5%.(2) The preparation and photocatalytic performance of ZnO/Ni composite photocatalyst.Ni-decorated ZnO composite photocatalyst with magnetic separable characteristics wasfabricated by hydrothermal method. It was researched for utilizing the amount of Ni doping toeffect the crystallization, microstructure and photoelectric properties of ZnO. Compositephotocatalyst was made of ZnO nanorod, prism and sheet-like ZnO particles. It had the bestphotocatalytic activity under UV light irradiation when the doping amount of Ni was9.0%,the degradation rate for KN-R was94.31%.(3) The preparation and photocatalytic performance of ZnO/Ni/CQDs compositephotocatalyst.In this paper, CQDs solution was selected as substituted materials instead of watersolvent in the hydrothermal fabrication of ZnO/Ni to make ZnO/Ni/CQDs photocatalyst. Theeffect of preparation conditions of CQDs, CQDs dosage, hydrothermal time and hydrothermal temperature on micro-structural, optical and electrical properties of ZnO/Ni/CQDs compositephotocatalyst was investigated. ZnO/Ni/CQDs was fabricated by hydrothermal method with50mL CQDs aqueous solutions which was prepared with glucose as carbon source，PEG-200as passivator and the mixture was heated in a microwave for150s when the hydrothermaltemperature is180℃and the hydrothermal time is120min. In this time, the photocatalysthad the best photocatalytic activity and the photodegradation for KN-R was96.19%underUV light irradiation. CQDs was amorphous carbon, the average particle size was2-4nm andit had green fluorescent under UV light irradiation. ZnO/Ni/CQDs composite photocatalystwas FTX polygon, while the shape was regular and the particle size was homogeneous.