Photosensitized growth of TiO2 nanoparticles improved the charge transfer dynamics of a bichromophoric dye

► TiO2 nanoparticles were synthesized via a photolytic process. ► XPS results show the TiO2 surface states have nearly defect-free distributions of Ti4+ and O2− energy levels. ► Efficiently suppressed grain boundaries and surface traps. ► Charge-transfer dynamics between TiO2/dye interfaces exhibited efficiently at a low TiO2 content.