Enhanced performance of sodium doped TiO2 nanorods based dye sensitized solar cells sensitized with extract from petals of Hibiscus sabdariffa (Roselle)

Sodium (Na) doped titanium dioxide (TiO2) nanorods were successfully synthesized by one-step hydrothermal method. The effect of sodium doping in improving the performance of dye sensitized solar cells (DSSC) has been discussed. Field Emission scanning electron micrograph (FESEM) revealed the formation of nanorods and nanoflowers for doped samples. X-ray diffraction (XRD) pattern of doped samples reveal slight shift towards lower angle confirming the effective substitution of Ti4+ by Na+. The photoelectric conversion efficiency of 6% sodium doped TiO2 based DSSC was 1.65% and is 79% higher than the undoped TiO2 based DSSC that exhibited an efficiency of 0.92%. This improvement in efficiency is ascribed due to less electron-hole recombination rate.