This study describes the preparation by aerosol pyrolysis and characterization of pure and Mo containing semiconducting BiVO4 thin films for application as a photoanode in photoassisted water electrolysis and photoelectrocatalysis. The optimum deposition temperature was 650 degrees C. Pure BiVO4 films had a monoclinic distorted Scheelite structure. This polymorph has a lower bandgap (2.4 eV) than the tetragonal zircon group phase (2.9 eV), which makes it more desirable for solar irradiation based photo(electro)chemical applications. Addition of Mo (14%) led to the formation of the tetragonal Scheelite type phase and significantly increased the photocurrent (from 20 to 400 mu A/cm(2) and from 400 to 1100 mu A/cm(2) at 0.6 V and 1.2 V vs. Ag/AgCl, respectively, under AM1.5 simulated solar illumination). The IPCE (incident photon to current conversion efficiency) at 405 nm was 0.24 for backside illumination at 2 V vs. RHE.