Arsenic and Chlorine Co-Doping to CH3NH3PbI3 Perovskite Solar Cells

Arsenic (As) and chlorine (Cl) were co-doped to CH3NH3PbI3 perovskite solar cells, and the photovoltaic properties were investigated. AsI3 and NH4Cl were added to perovskite precursor solution, which were deposited on mesoporous TiO2 by a spin-coating combining an air flow method. Current density-voltage characteristics and incident photon-to-current conversion efficiencies were improved by the co-doping of As and Cl to the perovskite phase, which also indicated an energy gap of 1.57 eV. X-ray diffraction showed suppression of PbI2 formation by the AsI3 addition. The structure analysis by scanning electron microscopy indicated formation of a homogeneous microstructure by adding AsI3 with NH4Cl, which would result in the improvement of the photovoltaic properties.