Effect of hydroxyl group attachment on TiO2 films for dye-sensitized solar cells

► A facile method is presented to attach OH groups on TiO2 photoelectrodes by thermal treatment in H2O2-saturated argon. ► More surface groups were generated by H2O2 treatment than by other previously reported methods. ► The amount of dye adsorption was increased and the efficiency of the DSSC was enhanced.