Synthesis of TiO₂ nanorice and their improved dye sensitized solar cells performance

TiO₂ nanostructures with different morphologies were successfully synthesized via a solvothermal reaction of titanium isopropoxide and acetic acid. The synthesized TiO₂ nanostructures were characterizated in detail by powder X-ray diffractometry, scanning electron microscopy, Fourier transform infrared spectroscopy and Raman etc. technologies. The effect of growth time on the composition, morphology and crystal phase of synthesized TiO₂ nanostructures were studied, and corresponding photovoltaic performance of dye-sensitized solar cell (DSSC) fabricated from TiO₂ nanorice was also investigated. The DSSC based on the 24 h anatase TiO₂ nanorice photoelectrode shows an overall light-to-electricity conversion efficiency of 7.45% accompanying a short-circuit current density of 18.83 mA cm⁻², an open-circuit voltage of 788 mV and fill factor of 0.5, which is much higher than that of 12 h (5.25%), 16 h (5.73%) and 20 h (6.20%) samples. The significant enhancement of short-circuit current density and power conversion efficiency for the 24 h nanorice-based DSSC is mainly attributed to its larger dye loading amount.