Silicon phthalocyanine passivation for fullerene-free perovskite solar cells with efficient electron extraction

Replacing fullerene with other organic materials is important for exploring perovskite solar cells (PVSCs) with better diversity and performance. In this study, a passivation/transport bilayer structure is employed in fullerene-free perovskite solar cells. The proposed fullerene-free PVSCs based on MAPbI 3 show power conversion efficiency of up to 19.2%, which is among the best value reported so far. We have demonstrated that, besides employing an efficient electron transport layer, passivating the perovskite surface with silicon phthalocyanine based molecules (SiPc-Py-2) is a key issue to prevent current hysteresis and open-circuit voltage loss.