Comparison of Electrospun Titania and Zinc Oxide Nanofibers for Perovskite Solar Cells and Photocatalytic Degradation of Methyl Orange Dye

ZnO and TiO₂ are both well-known electron transport materials; however, an exact comparison of their performance, when fabricated under the same synthesis conditions, is missing in the literature. Considering this, we introduced a viable electrospinning route for the development of highly polycrystalline TiO₂ and ZnO nanofibers for an electron transport material (ETM) of perovskite solar cells and photocatalysts for textiles. Thanks to the effective tuning of band structure and morphology of TiO₂, a significant improvement in performance as compared to ZnO was observed when both were used as photoanodes and photocatalysts. X-ray diffraction detected polycrystalline structural properties and showed that peaks are highly corresponding to TiO₂ and ZnO. Morphological analysis was carried out with a scanning electron microscope, which revealed that nanofibers are long, uniform, and polycrystalline, having diameter in the nano regime. TiO₂ nanofibers are more aligned and electron-supportive for conduction as compared to ZnO nanofibers, which are dense and agglomerated at some points. Optoelectronic properties showed that TiO₂ and ZnO show absorption values in the range of ultraviolet, and visible range and band gap values for TiO₂ and ZnO were 3.3 and 3.2 eV, respectively. The TiO₂ band gap and semiconductor nature was more compatible for ETL as compared to ZnO. Electrical studies revealed that TiO₂ nanofibers have enhanced values of conductivity and sheet carrier mobility as compared to ZnO nanofibers. Therefore, a higher photovoltaic conversion efficiency and antibacterial activity was achieved for TiO₂ nanofibers (10.33%), as compared to ZnO (8.48%). In addition, the antibacterial activity of TiO₂ was also recorded as better than ZnO. Similarly, compared to ZnO nanofibers, TiO₂ nanofibers possess enhanced photoactivity for antimicrobial and dye degradation effects when applied to fabrics.