CH3NH3SnxPb(1–x)I3 Perovskite Solar Cells Covering up to 1060 nm

Abstract

We report photovoltaic performances of all-solid state Sn/Pb halide-based perovskite solar cells. The cell has the following composition: F-doped SnO₂ layered glass/compact titania layer/porous titania layer/CH₃NH₃Sn_xPb_(1–x)I₃/regioregular poly(3-hexylthiophene-2,5-diyl). Sn halide perovskite itself did not show photovoltaic properties. Photovoltaic properties were observed when PbI₂ was added in SnI₂. The best performance was obtained by using CH₃NH₃Sn_0.5Pb_0.5I₃ perovskite. 4.18% efficiency with open circuit voltage 0.42 V, fill factor 0.50, and short circuit current 20.04 mA/cm² are reported. The edge of the incident photon to current efficiency curve reached 1060 nm, which was 260 nm red-shifted compared with that of CH₃NH₃PbI₃ perovskite solar cells.