Study of the efficiency of N719 dye-sensitized solar cells with cadmium selenide (cdse) semiconductor

This study investigates the solvent-dependent charge-transfer behaviour and predicted photovoltaic performance of N719 dye-sensitized CdSe solar cells. Although N719-based DSSCs have been widely studied using TiO2 photoanodes, the N719/CdSe interface remains less explored, particularly from the perspective of reorganization energy, electronic coupling, and theoretical photovoltaic modelling. In this work, CdSe photoelectrodes were prepared and characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), and Ultraviolet–Visible (UV–Vis) spectroscopy to examine their structural and optical properties. The photovoltaic response was not obtained from direct illuminated J–V measurements; instead, current–voltage characteristics, fill factor, and power conversion efficiency were estimated theoretically using a charge-transfer model implemented in MATLAB. Two solvent systems, tert-butyl alcohol and ethanol, were compared to evaluate the influence of solvent dielectric properties on electron-transfer behaviour. The results show that tert-butyl alcohol provides lower reorganization energy and more favourable charge-transfer conditions than ethanol. The predicted efficiency reached 4.072% for tert-butyl alcohol, compared with 1.712% for ethanol. These findings suggest that solvent-dependent interfacial interactions play an important role in controlling charge-transfer efficiency and predicted photovoltaic performance in CdSe-based DSSCs. The results should be interpreted as theoretical predictions supported by material characterization, and future experimental J–V validation is recommended. Graphical abstract