Effect of the Seed Layer on Green Synthesis ZnO Thin Film and Its Electrical Applications

This study investigated the effect of a predeposited ZnO seed layer on the thin film grown on a glass substrate by the dip‐coating technique. The deposited ZnO nanostructures have been synthesized using an entirely green method, with parsley (Petroselinum crispum) leaf extract as a capping and stabilizing agent. X‐ray diffraction, UV–vis spectroscopy, EDX, and SEM techniques were used to characterize the crystal structure, optical properties, and surface morphology. The optical bandgap of ZnO obtained in this study is 3.37 eV. EDX results indicating homogeneity and stoichiometry of the ZnO thin film, with uniformity and element purity, confirm the effective deposition process and suggest the applicability of the ZnO thin film for optoelectronic applications. The SEM analysis indicates a continuous, high‐quality ZnO seed layer, which is crucial for the growth of a high‐quality thin film. Additionally, the deposited thin film exhibits a homogeneous ZnO NPs distribution across its entire surface. The I – V characteristic curve of ZnO/FTO represents that the photoresponse of the film under illumination is seven times greater than that of the thin film under dark conditions. The electrical properties confirm the effectiveness of the created ZnO thin film as an active electron transport layer in solar cell applications.