Fabrication and characterization of natural dye-sensitized solar cells using an efficient natural sensitizer derived from Laurus nobilis L

In this study, we present a novel natural dye extracted from Laurus nobilis L (bay leaf: BL) intended for application in Natural Dye-Sensitized Solar Cells (NDSSCs). The extraction process involved utilizing a maceration method with methanol as the solvent. A comparative analysis was conducted on NDSSCs fabricated with fluorinedoped tin oxide (FTO) and indium-doped tin oxide (ITO) substrates. Comprehensive characterization of the extracted natural dye and the fabricated NDSSCs was performed using various techniques, including ultraviolet-visible (UV-Vis) and Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, X-ray photoelectron spectroscopy (XPS), solar simulation (current-voltage characteristics), and electrochemical impedance spectroscopy (EIS). UV-Vis and FTIR spectroscopy confirmed the bonding of chlorophyll, a key component in the extracted dye, to the TiO2 surface. The BL dye exhibited a broad absorbance spectrum, and its adherence to the TiO2 surface was affirmed through UV-Vis spectroscopy. SEM analysis revealed a uniform distribution of the BL dye on the TiO2 surface, and EDX analysis confirmed the composition of the dye. XPS analysis provided evidence of the adherence of chlorophyll pigment to the TiO2 surface. Upon optimization, the NDSSC fabricated with the BL dye and FTO substrate demonstrated notable performance metrics, including a short-circuit current density (J(sc)) of 0.528 mA/cm(2), open-circuit voltage (V-oc) of 0.615 V, a high fill factor (FF) of 69.9%, and a photoelectron conversion efficiency (eta) of 0.227%. Conversely, the cell utilizing the ITO substrate exhibited lower performance, with values of V-oc, J(sc), P-max, FF, and eta at 0.589 V, 0.394 mA/cm(2), 0.163 mW/cm(2), 69.9%, and 0.163%, respectively. Additionally, electrochemical impedance spectroscopy (EIS) analysis provided insights into the charge transport properties of the fabricated NDSSCs. The best-performing FTO-NDSSC with the BL dye displayed a recombination resistance (R-2) of 90.8 Omega and a photoanode-electrolyte interface resistance of 83.2 Omega, surpassing that of the N3-based DSSC. The overall evaluation of parameters and performance indicators underscores the promising potential of the BL dye for diverse applications, warranting further exploration and investigation.