pH值对水热合成钒酸铋及性能的影响  

Effects of pH on Hydrothermal Synthesised Bismuth Vanadate Photocatalysts and Its Properties

作　　者：江丹丹[1] 李晓晨[1] 潘新革[1] 王伟[1] 侯昭牧[1] 

机构地区：[1]山东农业大学水利土木工程学院,泰安271018

出　　处：《材料导报》2013年第8期97-100,104,共5页Materials Reports

基　　金：国家自然科学基金(51208174)

摘　　要：以硝酸铋和偏钒酸铵为无机源,NaOH为pH值调节剂,利用水热法制备了多种结构和形貌的BiVO4,并利用X射线衍射(XRD)、扫描电子显微镜(SEM)和紫外-可见吸收光谱(UV-vis DRS)等分析手段表征了其物化性质。结果表明前驱液的pH值对制得BiVO4产物的晶型和粒子形貌有很大影响。考察了BiVO4样品在可见光(λ>420nm)下降解罗丹明B的催化活性和总有机碳(TOC)浓度的变化,结果表明前驱液pH值为6.7时所得BiVO4具有最好的光催化活性,可见光催化4h后,罗丹明B的降解率达到95.3%。TOC值随着光解反应时间的延长而减小,表明罗丹明B发生了矿化。另外,对BiVO4光催化剂的晶型、形貌和性能之间的联系也进行了简单的探讨。Bismuth vanadate （BiVO4） powders were synthesized using the hydrothermal strategy with bismuth nitrate and ammonium metavanadate as inorganic sources, NaOH for pH adjustment. The materials were characterized by X-ray diffraction（XRD）, scanning electron microscopy（SEM） and UV-vis diffuse reflectance spectra techniques （UV-vis DRS）. It revealed that the pH values of the precursors can influence significantly on the particle structures and morphologies of the BiVO4 products. The decomposition of rhodamine B（RhB） in aqueous solution under visible light（λ 〉 420 nm）irradiation and variation of TOC concentration were evaluated. The results showed that photocata- lytic activities of BiVO4 samples prepared at different pHs varies greatly, and the optimum pH value is about 6. 7, which photodegradation rate could be up to 95.3% in 4 h, the reduction of TOC concentration in the degradation of RhB indicated that the mineralization of RhB occurred. Additionally, the relationship between the phase, morphology of photocatalysts and their photocatalytic activities are also discussed.

关 键 词：钒酸铋 水热合成 形貌 可见光催化活性 罗丹明B 

分 类 号：O643[理学—物理化学]