ZnO/Pd光催化降解偏二甲肼废水

为提高ZnO光量子产率、拓展光谱吸收范围,促进光催化降解低浓度偏二甲肼废水,研究采用贵金属Pd修饰乙醇辅助水热法制备出纳米Pd/ZnO颗粒,并对其进行了X射线衍射、扫描电镜、X射线能谱和紫外-可见吸收光谱的表征。将所得ZnO/Pd分别在紫外光和太阳光下光催化降解偏二甲肼废水。结果表明,Pd大幅提高了ZnO紫外吸收性能,且将其吸收光谱范围拓展到400~800 nm的可见光区域。ZnO/Pd纳米粒子在紫外光下对偏二甲肼2 h最大降解率为76.8%,化学需氧量(C O D)的去除率能达到58.2%,在太阳光下偏二甲肼降解率为80.5%,COD的去除率能达到75.7%。因此,ZnO/Pd的光催化性能在太阳光下比紫外光下好,太阳光下偏二甲肼中间产物被分解得更快、更彻底。

Photocatalytic Degradation of UDMH Wastewater with Nano particles of ZnO/Pd

The nano ZnO/Pd particles with the crystallite size about 41-46 nm were synthesized by hydrothermal method and ethanol-assisted hydrothermal method with Zn²⁺and Pd²⁺molar ratio of 100:0.5, 100:1, 100:2.The samples of ZnO/Pd were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), energy dispersive X-ray spectrometry(EDS), ultraviolet-visible spectroscopy(UV-vis) and were used in the photocatalysis of unsymnetrical dimethylhydrazine(UDMH) wastewater under UV-light and sun light.Results show that the UV absorbtion property is extremely expanded by doping Pd, and ranged to 400-800 nm in visible light district.The maximum degradation rate of ZnO/Pd in sunlight is 80.5% and under UV-light is 76.8% in 2 h.The variation of the photocatalytic middle-product under different light sources was analyzed at last.It is found that the middle-product is decomposed more quickly and throughly under sunlight, with COD degradation rate of 75.7%, which is better than UV-light of 58.2%.