Influence of doping the inorganic cation with Eu or Sb on the properties of perovskite films

This study reports on the results obtained after doping the [CH₃NH₃]_0.94[C₃N₂H₅]_0.06PbI_2.6Cl_0.4 mixt halide perovskite with europium or antimony (Eu³⁺/Sb³⁺) at the 'B site'. This way two new complex compounds were obtained, [CH₃NH₃]_0.94[C₃N₂H₅]_0.06Pb_1-yB_yI_2.6Cl_0.4 (B = Eu or Sb and y = 0–0.05) as perovskite precursor solutions and deposited as thin films. The properties of the perovskite films were investigated by various characterization techniques: x-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), UV–vis spectroscopy while the photovoltaic parameters were determined by measuring the IV curves of the corresponding solar cells. We find that doping the mixt halide perovskite with very small quantities of Sb improves the quality of the perovskite films and further improves the stability of perovskite solar cells. (paper)