Sustained production of H2O2 on irradiated TiO2– fluoride systems

UV irradiation of fluorinated TiO2 suspensions in water, in the presence of oxygen and a hole scavenger, leads to the production of H2O2 with steady state concentration levels up to 1.3 millimolar; the H2O2 formation rate follows the TiO2 surface speciation, being maximum when the surface is completely covered by (identical)Ti–F groups; these results outline the importance of surface speciation on the photocatalytic process.