Studies of photo-induced charge transfer properties of ZnWO4 photocatalyst

Abstract: Different sizes of ZnWO4 photocatalysts were synthesized by a hydrothermal method. The as-prepared sample shows highly efficient photocatalytic activity for the degradation of RhB under UV irradiation, which significantly vary with the increase of the hydrothermal temperatures. Surface photovoltage spectrum (SPS), field-induced surface photovoltage spectrum (FI-SPS) and surface photovoltage transient (TPV) techniques are used to investigate the detailed photoinduced charge transfer behavior. Results indicate that the ZnWO4 synthesized at 413K possess the largest BET surface area and the abundant donor surface states which are assumed to inhibit the recombination of the photogenerated electron–hole pairs, and thus a significant enhancement in the reaction rate is observed. [Copyright &y& Elsevier]