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Bi-doped TiO2was prepared with sol-gel method and was characterized by X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), X-ray diffraction (XRD), UV-visible diffuse reflectance spectroscopy (UV-vis DRS) and Fourier transform infrared spectroscopy (FTIR). Bi-doped TiO2 particles were nearly spherical with about 10 nm in size. Analysis by XPS indicated that the introduced Bi was probably incorporated into TiO2and may replace Ti. FTIR analysis found that doping Bi could enhance the hydrophilicity of TiO2. A red-shift of the absorption edge in the spectrum of UV-vis absorption was observed. Under xenon lamp irradiation, the Bi-doped TiO2exhibited enhanced photodegradation efficiency than TiO2, and the kinetic constant of MO removal with Bi-Ti-0.006 (0.011 min-1) was 3.8 times as great as that with TiO2(0.0029 min-1). The remarkably enhanced photocatalytic ability was attributed to the improved hydrophilicity and increased light absorption ability.

CdS/ZnS/TiO2 composite photocatalyst was prepared by sol-gel and immersion method. The optimum preparation conditions were as follows: the mole ratio of XS (CdS, ZnS) and TiO2 was 1:100; the mole ratio of CdS and ZnS was 1:1; calcined temperature 500℃; calcined time 1h. The optimum photocatalytic reaction conditions were as follows: the concentration of methyl orange 20mg/L, pH 5-7 and the catalyst dosage 2g/L. The removal rates of color and TOC were 84.3% and 54.2% using CdS/ZnS/TiO2 under the Visible light irradiation, respectively.

TiO2/AC composite was prepared by sol-gel method. The effect of annealed temperature and loading (or doping) ratio of AC on photocatalytic performances of TiO2/AC composite was explored. The optimum preparation conditions were 400 ℃ (annealed temperatur) and 2% (loading (or doping) ratio of AC). The experimental results of MB removal showed that the photocatalytic ability of TiO2/AC composite prepared under optimum conditions was higher than that of TiO2, which could be attributed to strong adsorption capacity, efficient photoproduced electron-hole separation, and higher light response.

Porous BiVO4 was fabricated by hydrothermal method with P123 as the template. SEM revealed there were many pores in porous BiVO4. DRS analysis indicated that the absorbance of BiVO4 was enhanced by constructing porous structure. The results of MB removal showed that the degradation rate with porous BiVO4 was 3.05 times as much as that with BiVO4. The enhanced photocatalytic performance was attributed to the enhanced absorbance ability and promoted surface reactions.

In this paper, synthesis of RuO2 with uniform nanosized sphere-like morphologies by ultrasonic precipitation using ammonia is presented. The structures, properties and electrocatalytic performance of materials were characterized by XRD, FE-SEM, CV and polarization curve. FE-SEM photographs showed that the sample prepared by ultrasonic precipitation has a relatively narrow size distribution compared with the sample prepared by conventional precipitation with magnetic stirring. The CV and polarization curve for OER (oxygen evolution reaction) confirmed that electrochemical active surface area and OER activity of sample by ultrasonic precipitation are higher than that of sample by conventional precipitation under magnetic stirring.