Can the phase-pure BiVO4 (010) epitaxial film be fabricated with a stoichiometric target?

Abstract

Bismuth vanadate (BiVO4) is the most promising visible light responsive photocatalytic material that can effectively transform solar energy into chemical fuel. Here, we used a stoichiometric target to systematically investigate the effects of substrate temperature, oxygen partial pressure and deposition time on the growth of monoclinic BiVO4 (010) epitaxial film prepared using pulsed laser deposition. The film was characterized systematically by x-ray diffraction, atomic force microscopy, x-ray photoelectron spectroscopy and UV–visible absorption spectroscopy. The phase-pure epitaxial thin film of BiVO4 could be fabricated at 680 °C under the oxygen partial pressure of 43 mTorr after depositing for 1 h. The film contains lot of square and rectangular flaky islands. The optical band gap is 2.55 eV.