Preparation Of Noble Metal-ZnO-RGO Photocatalysts And Study On Photodegration Performance

Nowadays,with the rapidly development of industries, the pollution of water environment has seriously affected people’s daily life. Among various of waste water treatment technologies, photocatalytic technology has attracted a lot of attention because it is green, environmental, effective and so on. Zn O semiconductor has a wide band gap of 3.37 e V, high exciton binding energy of 60 me V, high thermal stability and chemical stability, less of point defect and dislocation, and its morphology is easy to control, raw materials is cheap, the preparation process is simple, so Zn O is widely used in ultraviolet light emitter, solar cell, electronic products, piezoelectric transducer and other fields.But the optical stability of Zn O is undesirability, so Zn O is not used its own in photocatalytic technology. In this paper, we expect to enhance the optical stability of Zn O, restrain the recombination of photoelectron and vacation, easierly to recycle and enhance the adsorption property and electron transport performance in virtue of noble metal deposition and the location of RGO.We prepared a ternary composite catalyst Au/Zn O/RGO by one-step method.Au/Zn O/RGO was characterized by X-ray diffraction(XRD), Raman spectrum,infrared spectrum(FT-IR), scanning electron microscope(SEM) and transmission electron microscopy(TEM). The results show that Au/Zn O/RGO was in high purity, uniform dispersion, and good crystallinity. Au/Zn O/RGO shows good photocatalytic performance, which can degradation 98% Rhodamin B in 100 min. It demonstrates that Au/Zn O/RGO will be the best state when the input is 50 mg, the concentration of Rh B is 5mg/L, the light is 365 nm and the p H is 11.Then, we prepared another ternary composite catalyst Ag/Zn O/RGO by in-situ sythesis method. The results of X-ray diffraction(XRD), Raman spectrum, infrared spectrum(FT-IR), scanning electron microscope(SEM) and transmission electron microscopy(TEM) show Ag/Zn O/RGO has a good structrue. The study of photocatalytic degradation of Rh B demonstrations the rate of Ag/Zn O/RGOcan reach99.8% in 70 min which is 30% higher than that of Au/Zn O/RGO, show a better performance than Au/Zn O/RGO. It is similar to Au/Zn O/RGO that Ag/Zn O/RGO will be the best state when the input is 50 mg, the concentration of Rh B is 5mg/L, the light is365 nm and the p H is 11.Finally, we briefly study the role of ?OH in the photocatalysis of Au/Zn O/RGO and Ag/Zn O/RGO.