Photoelectrochemical performance of TiO2-nanotube-array film modified by decoration of TiO2 via liquid phase deposition

TiO2-nanotube-array film, fabricated by electrochemical anodization of Ti foil, was modified by TiO2 nanoparticle decoration via a liquid phase deposition (LPD) process. The films were characterized by FESEM, XRD and UV/Vis spectroscopy. For TiO2-nanotube-array films employed as photoanodes, the photoelectrochemical behaviors were investigated in a three-electrode electrochemical system under UV illumination. By integrating TiO2-nanotube-array films into the DSSC structure using a commercially available ruthenium-based dye, the photoelectric conversion performances were also investigated. The results show that TiO2 nanotube arrays have been decorated by TiO2 nanoparticles via LPD. The improved photoelectrochemical performances for the decorated TiO2-nanotube-array film could be attributed to the effective charge separation. An overall 114.5% increase of the photoelectric conversion efficiency of the DSSC has been achieved owing to LPD modification on the TiO2-nanotube-array film.