可见光响应Bi2WO6薄膜的制备与光电化学性能

采用非晶态配合物-提拉法在ITO导电玻璃基底上制备得到Bi2WO6薄膜. 采用FE-SEM、XRD、Raman、DRS、光电流响应谱、IPCE等手段, 研究了Bi2WO6薄膜的形貌、结构、光电性能以及薄膜结构与光电性能的关系. 结果表明, 450 ℃以上煅烧可以得到Bi2WO6结晶薄膜, 薄膜由沿(131)晶面趋向生长的Bi2WO6纳米颗粒组成, 颗粒的粒度随煅烧温度的升高而增大, 同时颗粒之间的间距也相应增大. ITO/Bi2WO6薄膜电极在可见光(λ>400 nm)照射下可以产生光电流, 光电流强度与光强度线性相关; 光电流强度和光电转换量子效率受Bi2WO6薄膜结构的影响, 通过控制薄膜的煅烧温度等制备条件, 可以提高薄膜光电极的光电转换量子效率.

Preparation and Photoelectrochemical Properties of Bi2WO6 Films with Visible Light Response

The Bi2WO6 films on ITO glass substrates have been prepared from amorphous complex precursor by dip-coating technique. The structure and photoelectrochemical properties of the films were investigated by using FE-SEM, XRD, Raman, DRS, IPCE (incident photon-to-current conversion efficiency) and photocurrent action curves. The crystalline Bi2WO6 film could be obtained above 450 ℃, which was composed of Bi2WO6 nanoparticles growing along (131) face. The size of Bi2WO6 nanoparticles was increased with the calcination temperature, and the space between the nanoparticles also increased. Under the visible light (λ>400 nm) irradiation, the photocurrent was generated from the ITO/Bi2WO6 photo-electrode, with the photocurrent density linear to the light intensity. The photocurrent density and IPCE can be controlled by modifying the surface structure of Bi2WO6 films, which can be achieved by changing the preparation conditions (such as calcination temperature).