Photocatalytic Hydrogen or Oxygen Evolution from Water over S- or N-DopedTiO2under Visible Light

摘要

S- or N-doping ofTiO2powder having an anatase or rutile phase extended thephotocatalytic activity for water oxidation and reduction under UV light and visible lightirradiation. For the reduction of water, anatase-dopedTiO2showed higher level ofactivity than that of dopedTiO2having a rutile phase using ethanol as an electron donor.Furthermore, the activity level of S-dopedTiO2for hydrogen evolution was higher thanthat of N-dopedTiO2photocatalysts under visible light. Photocatalytic oxidation of wateron dopedTiO2having a rutile phase proceeded with fairly high efficiency whenFe3+ionswere used as electron acceptors compared to that on dopedTiO2having an anatase phase.In addition, water splitting under visible light irradiation was achieved by construction ofa Z-scheme photocatalysis system employing the dopedTiO2having anatase and rutilephases forH2andO2evolution and theI−/IO3−redox couple as an electron relay.