BiPO4／Ag3PO4新型可见光催化剂的制备及其性能研究

A study on preparation of BiPO_4/Ag_3PO_4 novel visible light responsible photocatalysts and their photocatalytic performance

采用共沉淀法,在不同焙烧温度下,以AgNO3,Bi(NO3)3.5H2O和NaH2PO4为原料合成了一系列不同BiPO4与Ag3PO4掺杂比例的BiPO4/Ag3PO4复合型光催化剂,采用紫外可见漫反射光谱、扫描电子显微镜、荧光光谱等技术对所得光催化剂的光吸收区间、形貌、光致发光等性质进行了表征.结果显示,这些光催化剂能吸收400～500 nm波长的光,是一类新型的可见光催化剂.通过罗丹明B的可见光催化降解评价了该类光催化剂的活性.随着掺杂比例的增大,光催化活性依次减弱;随着焙烧温度的升高,光催化活性先增强后减弱.焙烧温度为350℃,BiPO4与Ag3PO4的摩尔百分比为5%的光催化剂活性最高,在40 min内可将200 mL浓度为12 mg/L的罗丹明B溶液完全降解.

A series of BiPO4/Ag3PO4composite photocatalysts with different doping proportion of BiPO4and Ag3PO4were synthesized using AgNO3 Bi （NO3 ）3 · 5H2O and NaH2PO4as raw materials by a co -precipitation method at different calcination temperature. The properties of the photocatalysts, including light - absorption band, morphology and photoluminescence, etc were characterized by UV- Vis diffuse reflectance spectra, scanning electron microscopy and fluorescence spectrum. The results showed that these composite photocatalysts absorb visible light with the wavelength of 400 - 500 nm, and hence are novel visible light responsive photoeatalysts. The photocatalytic activity of the photocatalysts was tested in degradation of Rhodamine B. With the increase of doping ratio, the photocatalytic activity decreases. With the enhancement of calcination temperature, the photocatalytic activity firstly increases, and then decreases. The photocatalyst with the BiPOJAg3PO4 molar percent of 5% that was obtained by calcining at 350 ℃ showed the optimal activity, which is the complete degradation of 200 mL rhodamine B solution with a concentration of 12 mg/L within 40 minutes.