Investigation of N520 dye sensitization in dye-sensitized solar cells using SnO₂/ZnO composite

Dye-sensitized solar cells (DSSCs) are photovoltaic devices that convert sunlight into electricity. DSSCs rely on photochemical process unlike conventional silicon based solar cells, which makes them cost effective and capable of working under low-light conditions. A photosensitized dye is used to capture sunlight and initiate electron transfer in dye-sensitized solar cells. This study addresses the lack of research on N520 dye in DSSCs by evaluating its performance with a SnO₂/ZnO composite photo anode. While SnO₂/ZnO has been explored with other dyes, its application with N520 remains understudied. The device manufacturing process involves applying semiconductor oxide layers to FTO substrates by the spray-coating method. Then the cells were sintered at 500 °C for 30 minutes. The sintered cells were dipped in N520 dye solution for 24 hours, and the solar cells were assembled with a platinum counter electrode and an iodide/triiodide liquid electrolyte. The performance evaluation was done using J-V measurements using a solar simulator. Among the three photoanode materials; SnO₂, ZnO and SnO₂/ZnO composite, the SnO₂/ZnO composite yielded the highest performance with a power conversion efficiency of 1.88%, a short-circuit current density (J sc) of 4.53 mA/cm², open circuit voltage (Voc) of 580.58 mV and a fill factor (FF) of 0.71. Improved performance in the system is caused by more efficient electron transfer and less recombination at the heterojunction interface. UV-Vis spectroscopy confirmed strong absorption at 528 nm due to the conjugated system of the dye, while Raman spectra verified the presence of characteristic vibrational peaks, indicating successful dye adsorption. Even though this dye has limited previous studies, these findings suggest its potential for further development.