Tahmineh Jalali

Here, we demonstrated that outstanding electrical and morphological characteristics of TiO2 nanofibres sensitized by the cocktail of natural dyes can effectively improve and stabilize the dye-sensitized solar cells (DSSCs). The TiO2 nanofibres were fabricated using a cost-effective and applicable electrospinning technique. The FESEM results demonstrated that the continuous bead-free nanofibres were successfully fabricated, which indicates good control of the electrospinning conditions. Based on the BET results, the transformation of nanoparticles to nanofibres increased the BET surface area and pore size. Then, a facile one-step approach was employed to fabricate TiO2 nanofibres-based DSSCs that produced a highly porous network of TiO2 without the nanofibre layer undergoing multiple cracks upon calcination. Based on the photovoltaic results, the DSSCs fabricated by the electrospun TiO2 nanofibres showed the highest I_sc, V_oc, and η of 1.80 mA, 0.40 V, and 1.24%, respectively. This is because that the one-dimensional morphology of electrospun nanofibres provides better charge conduction due to the combined effect of the reduced grain boundaries and a higher specific surface area. The results also showed that the DSSC based on the TiO2 nanofibres retained about 63% of its initial efficiency after 14 days, while DSSCs based on the TiO2 nanoparticles maintained about 27%, respectively.