Designing transparent conducting electrodes to enhance the performance of large-area perovskite solar cells

In solar cell research, the transparent conducting electrode (TCE) is typically not included in device optimization. In this study, we investigate the properties of TCEs to identify the most important one(s) for the performance of large-area perovskite solar cells (PSCs), which is vital in advancing their commercial viability. By keeping the absorber and the PSC device structure constant, we pinpoint the TCE conductivity as the critical factor. We then design a hybrid TCE, composed of silver nanowires (AgNWs) and indium zinc oxide layers on polyethylene terephthalate (PET) substrate, that has a sheet resistance (R□) lower by a factor of two (~ 5.7 vs. 9.8 Ω □ -1 ), with only a minor trade-off in average transmittance and surface roughness. 1.4 cm 2 PSCs fabricated on the lower-R□ hybrid TCE have enhanced PSC performance due to improved fill factor (FF). Furthermore, we show that the FF and power conversion efficiency of the 1.4 cm 2 area PSCs decrease with increasing series resistance, which is not observed for the 0.1 cm 2 area PSCs. Finally, technology computer-aided design simulations further confirm the experimental results and indicate that the TCE R□ must be below 10 Ω □ -1 to achieve good performance in large-area devices. These findings highlight the importance of TCE design for specific applications and that AgNW-based TCEs offer an effective pathway to improving the performance of large-area PSCs.