| At the time of physical life level continuously raises, the indoor air pollution becomes gradually serious in the meantime. The indoor air pollution causes people's attention day by day because of the descent of the indoor air quality to influence people health and work efficiency. Among of them, the volatility organic compounds ( VOCs ) is a type of pollutant which is very widespread and endanger to the human body, it mainly comes from indoor fitment and furniture. It has the characters: various in category, complicated composition, long-term low doses release, harmful to human body and difficult in disposal etc. People try to find a new better technique to resolve the problem of indoor air pollution in recent times.Since TiO2 was found to be an efficient photocatalyst, it has attracted great attention as an alternative material to use in the purification of water and air. Photocatalysis with TiO2 presents some distinct advantages: high TiO2 chemical stability in a large pH range, low cost of catalyst and chemicals, none or low inhibitions by common ions present in water, relatively mild reaction conditions required and success in the decomposition of several toxic refractory pollutants. When exposed to light, a titanium dioxide photocatalyst generates an extremely strong oxidizing power that oxidizes harmful substances, such as microbes, molds, odors, or soils that come into contact, and eliminates them by decomposition into carbon dioxide, water and other small molecules. Yet, the implementation of photocatalysis for practical use at large scale is still a challenging matter of investigation because of the low photocatalytic activity and working only in the UV region. So, developing a novel photocatalysts with high activity and working in the visible region is one of challenges facing photocatalysis area.To increase the reaction activity, doping TiO2 with metal oxides is one of the most efficiency way. Though the mechanism of the doping is still remain unclear, it has received a lot of attention in the last decades, and it has been made a huge progress in the improvement of enhancing photocatalytic efficiency. Many metal oxides, such as Cd-TiO2, Fe -TiO2 Ni- TiO2, V- TiO2, Mg- TiO2, Ce- TiO2, have commonly been used.Recently, a few innovative methods were proposed to low its band gap and shift its optical response to the visible region by doping TiO2 with nonmetal element. For example, doping TiO2 with N, C, or B can lower its band gap and shift its optical response to the visible region.In this study, we report on doped TiO2 with both a metal oxide, Fe2O3, and a nonmetal element, boron, by a simple method of sol-gel synthesis. X-ray Diffraction (XRD) was used to analyze the structure of the photocatalyst. The physicochemical properties of samples were characterized by UV-Vis diffuse reflectance spectra (DRS) and fluorescence spectrometry (FS). Herein we chose formaldehyde as target pollutant, because of it's a common component of VOCs (volatile organic compounds) and awfully harmful to human body.According to the experiments and our study, the results showed that the effect of B doping in TiO2 can extend the spectral response to the visible region and that the reaction activity is extraordinarily enhanced when it is further loaded with Fe2O3.
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