The bismuth nanoparticles are synthesized via a solvothermal reduction method based on the chemical reduction of Bi3+ by ethylene glycol acting as the solvent and the reducing agent. The structural and morphological properties of the bismuth nanoparticles are investigated by X-ray diffraction and scanning electron microscope. The results demonstrate that the synthesized powders has a rhombohedral crystalline structure and their diameters are in the range of 75-103 nm under the condition of the different initial bismuth nitrate concentrations with the reduction temperature of 200°C, indicating that the thermal reduction temperature and the initial bismuth nitrate concentrations are key factors for phase composition as well as crystal size.

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Cu-doped TiO2 photocatalysts were synthesized by a homogeneous hydrolysis and low temperature crystallization method using tetrabutyl titanate as the titanium source and cupric acetate as the doping agent. The phase structure, composition and morphology of the product were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDS) and Brunauer-Emmett-Teller surface area analysis (BET). The XRD results confirmed that the crystalline phase of all prepared samples was anatase-type TiO2. SEM results showed that the Cu-doped TiO2 were composed of spherical particles with particle diameter smaller than 20 nm. Furthermore, the photocatalytic activity of the Cu-doped TiO2 catalysts were evaluated based on the photocatalytic degradation of methyl orange (MO) in aqueous solution. The results showed that Cu-doped TiO2 had the higher visible-light-induced catalytic activity than the commercial P25 TiO2 powder. The copper content in Cu-doped TiO2 had obvious effect on the visible-light-induced catalytic activity, and the degradation rate of MO could reach 33.7% using Cu-doped TiO2 with a doping level of 1.0 mol% Cu as a photocatalyst under the visible light irradiation for 3 hours.

Ca-Mg-Al hydrotalcite-like compounds (CaMgAl-HTLcs) were synthesized by a hydrothermal method, and characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and differential thermal analysis (DTA) techniques. The effects of the medium pH value, the molar ratio of the raw materials, the reaction temperature and the reaction time on the structure of CaMgAl-HTLcs were studied. The results showed that increasing treatment temperature and reaction time could improve the crystallinity and monodispersity of hydrotalcite-like compound particles. And well-defined CaMgAl-HTLcs could be prepared at a pH value of 10~11 with n (Mg+Ca): n (Al) = 1~3 and n (Mg): n (Ca) = 1~3.

Ca-Mg-Al hydrotalcite-like compounds (CaMgAl-HTLcs) were synthesized by a hydrothermal method, and characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and differential thermal analysis (DTA) techniques. The effects of the medium pH value, the molar ratio of the raw materials, the reaction temperature and the reaction time on the structure of CaMgAl-HTLcs were studied. The results showed that increasing treatment temperature and reaction time could improve the crystallinity and monodispersity of hydrotalcite-like compound particles. And well-defined CaMgAl-HTLcs could be prepared at a pH value of 10~11 with n(Zn+Mg+Ca):n(Al) =2. The products synthesized were applied to PVC to improve the thermal stability of PVC.