Catalytic Properties Of Bismuth-based Semiconductor Photocatalyst Preparation And Visible Light

The environment pollution has become an important issue in modern society. Currently, conventional waste treatment method is mainly the chemical oxidation method, the physical adsorption method, the biological degradation method, etc. However, these conventional methods have some defects. Since1970s, the selective supply of pollution-free environmental remediation technology and clean energy development aims to provide a new approach, which is semiconductor photocatalytic treatment. In particular, as one of the most important wide-band-gap semiconductors possessing unique chemical, electronic, and optical properties, anatase titanium dioxide(TiO2) has been studied extensively because of its great potential applications in photovoltaic cells, photo/electrochromics, photocatalysis, photonic crystals, smart surface coatings, and sensors. Thus, enormous efforts have been devoted to improving the photocatalytic activity of TiO2. In this paper, bismuth-based semiconductor photocatalytic was prepared to study the efficient new visible light response photocatalyst. A variety of new semiconductor nanostructures visible catalyst were prepared by hydrothermal and chemical co-precipitation method to perform organic dyes and photocatalytic mechanism, In this paper, the main contents are summarized as follows:1. Monoclinic BiVO4nano and microstructures with a diversity of well-defined morphologies, such as nanoplates, dendrite leaves-like structures, sub-microrods, and microflowers were synthesized via a template-free hydrothermal process. It was found that the pH value of the solution and the amount of ethylenediamine have great effects on the formation of these unique structures. The photocatalytic activity of these as-prepared samples had been tested by degradation of methylene blue under visible light, indicating that the pH=3,5,7samples showed good photocatalytic performance.2. High surface area BiOCl and BiOCl/TiO2nanostructures were synthesised by co-precipitation method, which is simple compared to the tedious synthesis process of chemical synthesis. The photocatalytic activity about nanosheets BiOCl has high efficiency when it under visible ligh. The result show that the degradation of dye can be completely degraded within10min of10mg/L methyl orange dye, completely degraded within19min of10mg/L with methylene blue dye. BiOCl/TiO2nanostructures can be completely degraded within10min of10mg/L Rhodamine B,10mg/L methyl orange dye is completely degraded within30minutes. First, BiOCl and BiOCl/TiO2composite structure has a larger surface area to provide the more reactive sites for the photocatalytic reaction; Second, the use of the band gap semiconductor composite BiOCl/TiO2composite structure is conducive to the absorption of visible light photosensitive mechanism to enhance the catalytic activity of the photocatalyst.3. Fe3O4nanoparticles and different mass fraction BiOCl/Fe3O4magnetic composite nanoparticles were synthesised by chemical coprecipitation respectively. Different concentrations BiOCl/Fe3O4magnetic composite nanostructured photocatalytic degradation of Rhodamine B were performed under visible light irradiation. The results show that10%BiOCl/Fe3O4magnetic composite nanostructures of rhodamine B showed high photocatalytic degradation of performance with the visible light irradiation, BiOCl/Fe3O4magnetic composite nano-structured magnetic media can be recycled repeatedly and maintain efficient, stable photocatalytic activity. BiOCl/Fe3O4magnetic composite nanostructures is expected to apply in the actual processing wastewater under visible light irradiation bright application prospect.