Performance of SnO2 nanorods prepared by vapour-liquid-solid technique for dye-sensitized solar cells
摘要
This study, well-ordered arrays of SnO2 NRs were synthesized on fluorine-doped tin oxide glass (FTO) substrates using a low-temperature vapor-liquid-solid (VLS) method at 550 °C in air. Structural properties, surface morphology, and optical properties of SnO2 NRs were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), diffuse reflectance spectroscopy, and UV-Vis spectroscopy. The performance of SnO₂-based DSSCs is fundamentally limited by significant charge recombination losses, primarily occurring at surface trap states within the SnO₂ nanostructures and via back-electron transfer at the SnO₂/FTO interface. The present work demonstrates that recombination issues persist. At the same time, the SnO2 NRs-based DSSC improves external quantum efficiency within the 400–700 nm wavelength range, as indicated by the non-ideal diode behavior (m ≈ 1.7). The photovoltaic parameters of DSSC based on SnO2 nanorod like open circuit voltage (VOC) and short-circuit current density (JSC) were 0.678 V and 2.15 mA/cm² respectively, while the fill factor (FF) was 0.56 indicates significant electrical losses. Open-circuit voltage decay and charge carrier lifetime analyses reveal that further optimization is required for higher efficiency. These findings suggest that SnO2 NRs have significant potential as photoanodes, but addressing surface traps and recombination is crucial for advancing their practical application in DSSCs.