Series resistance Rs is a fundamental parameter that significantly impacts the performance of photovoltaic devices. It influences the short-circuit current density Jsc and the fill factor (FF), which collectively determine the power conversion efficiency (PCE). An increase in series resistance leads to resistive losses, hindering charge carrier transport and reducing both Jsc and FF. This results in a noticeable drop in the overall efficiency of the device. The importance of minimizing Rs for enhancing device performance is well-supported by prior studies .