可见光响应的Bi-TiO_2的制备及其对间苯二酚的降解作用

Preparation of Bi-Doped TiO_2 Photoeatalyst and Their Visible-Light Photocatalytic Activity to Degradation of Resorcinol

以钛酸四丁酯、硝酸铋为原料,采用水热法制备铋掺杂TiO2光催化剂(Bi-TiO2)。所得材料用X射线衍射、透射电子显微镜、X射线能谱、X射线荧光光谱、UV–Vis漫反射等测试手段分析。结果显示水热法可以直接合成锐钛型纳米TiO2。铋在TiO2中的掺杂方式为Bi3+替位取代TiO2中Ti4+。样品具有较大的比表面积,其最大达31.2 m2/g。铋掺杂能引起TiO2光催化剂的吸收光谱明显红移,从而具备较好的可见光响应性。以降解间苯二酚为探针反应研究其可见光催化性能,纯TiO2光催化活性极低,而Bi-TiO2具有较高的可见光催化性能,当铋掺杂量为1.00%时光催化性能最佳。UV–Vis光谱和高效液相色谱显示间苯二酚在70W金卤灯下反应120min能完全分解。

Bi-TiO2 photocatalysts were prepared with tetrabutyl titanate and bismuth nitrate as raw materials by a hydrothermal method.The photocatalysts were characterized by X-ray diffraction,transmission electron microscopy,X-ray energy dispersive spectroscopy and X ray fluorescence,UV–Vis diffuse reflectance spectrophotometer.The results show that the nano-sized particles of Bi-TiO2 are prepared when Bi3＋ is substituted for Ti4＋.The specific surface area of the sample was up to 31.2 m2/g.Bi doping caused red-shift of the onset of the absorption spectrum,resulting in a better visible-light response.Bi-TiO2 shows a higher photocatalytic avtivity to the degradation of resorcinol,compared to pure TiO2.The optimum value of Ag doped was 1.00%.The degradation rate of resorcinol after 120 min illuminating by a metal halide lamp can obtain to 100% according to the analysis by UV-visible spectrum and HPLC.