可见光响应催化剂BiVO4六角形微米棒的水热合成

摘要

以Bi(N03)3·5H2O和NH4VO3为原料并以聚乙烯吡咯烷酮(PVP)为模板剂通过水热法制备了BiVO4六角形微米棒晶体.采用XRD、SEM、IR、Raman、UV-Vis、光催化等对产品进行了表征和分析.结果表明.PVP辅助水热法能够合成直径125～300 nm、长度在1.0-1.6μm岬内的形貌均一且结晶度高的单斜白钨矿BiV04六角形微米棒晶体.相比BiVO4颗粒,该棒状样品的紫外一可见光吸收边发生了稍许红移.其能带隙减小至2.25 eV.光催化结果表明,添加2.0 g PVP时的BiVO4微米棒对亚甲基蓝具有最强的可见光催化降解活性.其光照射浓度为10 mg·L-1亚甲基蓝溶液2 h时的降解率达到99%.%Using Bi (NO3)3·5H2O and NH4VO3 as raw materials, BiVO4 microrods with hexagon shape were synthesized by hydrothermal method with polyvinyl pyrrolidone (PVP) as template. The properties of the asprepared samples were characterized by XRD,SEM,IR,Raman and UV-Vis spectroscopy. The results reveal that uniform and well crystallized BiVO4 hexagon-microrods in monoclinic crystal structure could be obtained with dimeter of 125～300 nm and length of 1.0～1.6 μm via a hydrothermal route assited by PVP. Compared with BiVO4particles, the above obtained microrods by 2.0 g PVP show a small red shift in the absorption band and its narrowed band gap (2.25 eV). The catalytic results indicate that the photodegradation rate for methylene blue could reach 99％ with 10 mg·L-1 solution of methylene blue under visible-light irradiation for 2 h.