Work Function-Driven Performance Analysis of Silver Nanowire Back Contact Electrodes for Platinum and FTO-Free Dye-Sensitized Solar Cells

Dye-sensitized solar cells (DSSCs) are promising substitutes to conventional solar cells, provided their efficiency, stability, and cost effectiveness can be improved. The conventional fluorine-doped tin oxide (FTO) back contact electrodes used in DSSCs involve complex fabrication processes, increasing the overall costs. The work function of the back contact electrode plays a critical role in determining the charge extraction efficiency and overall photovoltaic performance in DSSCs. In this study, systematic investigations were performed on the back contact electrode’s work function influence on the efficiency of DSSCs by combining SCAPS-1D simulations with experimental validation. Guided by simulation results, DSSCs were fabricated using silver nanowire (AgNW)-based back contact electrodes, and their performance was compared to that of fluorine-doped tin oxide (FTO) and Pt-coated FTO electrodes. Experimental measurements show that AgNW electrodes achieve an efficiency of 4.2%, closer to 5.3% of Pt-deposited FTO and significantly outperforming the 2% efficiency obtained with bare FTO. The strong correlation between the simulated trends and experimental results confirms that the improved performance originates from the higher effective work function of the AgNW electrode. This work highlights that AgNW-based back contacts not only reduce material and fabrication costs but also provide favorable energetics for efficient charge collection, making them a promising alternative for scalable and FTO-free DSSC development.