SrTiO3/TiO2 Hybridstructure as Photoanode in Dye-Sensitized Solar Cell

Abstract

In dye-sensitized solar cells (DSSCs), the charge recombination at the TiO2/dye/electrolyte interface greatly influences the photoelectron conversion efficiency. Hybrid semiconductor materials with matched band potentials are designed to reduce the charge recombination. In this study, SrTiO3/TiO2 hybridstructure was synthesized by using TiO2 nanoparticles as template in a hydrothermal, showing a negative shift in the flat band potential. The DSSC with the SrTiO3/TiO2 anode exhibits an increased photovoltage and a reduced photocurrent. The suppression of charge recombination at the TiO2/dye/electrolyte interface was observed in the electrochemical impedance spectroscopy, causing an improvement in the photovoltage. However, the SrTiO3/TiO2 system shows an obstructed electrons injection from the dye to SrTiO3/TiO2, limiting the photocurrent performance. The photoelectrochemical properties of the SrTiO3/TiO2 system are discussed in detail herein.