Photoresponse of Undoped and W-Doped TiO2

Undoped andW-doped polycrystalline TiO2 were investigated. The kinetics of recombination processes has been studied. The flat band potential of TiO2 was determined (-0.11 V in respect to saturated calomel electrode, at pH = 7.8). Basing on the photocurrent experiments, the effect of Wconcentration on solar energy conversion efficiency was discussed. It was found, that addition ofWleads to an increase of solar-to-hydrogen energy efficiency. The maximum energy conversion efficiency has been observed for voltage bias ca 0.65 V. The highest energy conversion efficiency has been observed for TiO2 doped with 0.1 at % W.