Preparation and Photoelectrochemical Properties of Bi2MoO6 Films

Bi2MoO6 films on ITO glass substrates were prepared from amorphous complex precursor by dip-coating technique. The relationships between conditions of preparation, structures, morphologies, and photoelectrochemical properties of Bi2MoO6 films were investigated by using scanning electron microscopy (SEM), X-ray diffraction (XRD), laser Raman spectroscopy (LRS), diffuse reflectance spectroscopy (DRS), photocurrent-action curves, and incident photon-to-current conversion efficiency (IPCE). Bi2MoO6 films calcined at 500 °C for 1 h were the γ-Bi2MoO6 phase, and Bi2MoO6 nanoparticles grew along (131) plane. The thickness of the films obtained was about 69 nm. The size of Bi2MoO6 nanoparticles increased with rising calcination temperature and extension of calcination time; in addition, γ-Bi2MoO6 changed into β-Bi2MoO6 and γ′ -Bi2MoO6 at 525 °C. Bi2MoO6 films had visible-light response, and detectable photocurrent was generated under visible-light (λ>400 nm) irradiation. The IPCE of the optimized Bi2MoO6 films was 2.14% at 400 nm. The photocurrent density and IPCE could be controlled by modifying the surface structure of Bi2MoO6 films, which could be achieved by changing the preparation conditions.