Robust transparent Ag nanowire electrode for bifacial perovskite solar cells

Silver nanowire (Ag NW)-based transparent back electrodes prepared via all solution-process are promising for bifacial and semitransparent perovskite solar cells (PSCs). However, the inadequate electrical contact between the silver nanowires themselves and the contact with substrate leads to reduced overall solar cell performance; meanwhile, serious corrosion of Ag NW in ambient environment restricting the further applications. In this work, polyvinylpyrrolidone (PVP) as a binder in Ag NW electrode significantly enhances the conductivity and transparency at the same time improving the interface electric contact. The PSC with PVP modified Ag NW electrode demonstrated frontside and backside efficiency approaching 18% and 14.1% (AM1.5, 1 Sun), respectively, which achieves 82% efficiency with normal Ag device and bifacial factor of 79%. The long-term storage stability of PSC is also improved by PVP protection. The final device structure is ITO/NiOx/MeO/(FA0.92MA0.08)0.95Cs0.05Pb(I0.9Br0.1)3/PEAI/PC61BM/BCP/ Ag NW. This work highlights the method to fabricate robust transparent Ag NW electrode for bifacial perovskite solar cells.