Effect of Dip-Coating Cycles on the Structural and Performance of ZnO Thin Film-based DSSC

Deposition of thin film with good thickness uniformity and quality for fabrication of thin film-based dye-sensitized solar cells is a critical factor that determines the reliability and consistency of its photovoltaic performance. In this work, dip-coating method was used for the deposition of ZnO thin films on fluorine-doped tin oxide glass substrates. The structural, electrical and optical properties of these ZnO thin films were characterized by XRD, FESEM, four-point probe, UV-Vis spectroscope and room temperature PL spectroscope. The study showed that the thickness of ZnO thin film could be adjusted by the number of dipping cycles. By increasing the dip-coating cycles, the thickness, crystal quality and absorbance of visible light of ZnO thin films increased whereas the sheet resistance of ZnO thin films decreased. As a consequence, the photovoltaic performance of DSSCs improved with maximum conversion efficiency of 0.68% at 3 cycles of dip coating. Nevertheless, formation of macro-defects such as pores and cracks in thick ZnO thin films became the dominant factor that deteriorated their conversion efficiency down to 0.19% (at 11 cycles).

Automated summary

The study focused on depositing ZnO thin films on fluorine-doped tin oxide glass substrates using dip-coating method to improve the performance of dye-sensitized solar cells. By adjusting the number of dip-coating cycles, the thickness and properties of the ZnO thin films could be controlled, leading to enhanced photovoltaic performance.