| Micro-crystalline strontium titanate (SrTiO3) electrodes were fabricated by the deposition of particles synthesized via a sol-gel method and subsequent hydrothermal treatment. Bare SrTiO3 electrodes were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and impedance spectroscopy. Mott-Schottky analysis of the bare SrTiO3 films on conductive fluorine-doped tin oxide (FTO) substrates yielded a flat-band potential in the range of - 1.29V to -1.46V at pH = 13.6. A proposed band-diagram for the FTO/SrTiO3/electrolyte interface was generated from the Mott-Schottky and impedance measurements. Electrodes were sensitized with the ruthenium "N3" dye and tested as photoelectrodes in dye-sensitized solar cells (DSSCs). SrTiO3 electrodes exhibited variable morphology related to particle aggregate size, and the aggregate size depended upon the preparation technique. SrTiO 3 electrodes exhibiting smaller aggregates performed better in dye-sensitized solar cells compared to films with larger aggregate sizes. Current degradation was observed during the generation of current-voltage curves for illuminated DSSCs, which was attributed mainly to electrolyte evaporation. The best performing SrTiO3 DSSC yielded a short circuit current of 0.7 (mA/cm 2) and an open circuit voltage of 385 mV at 1 sun illumination. |
