Rietveld refinement of crystal structure of perovskite CH3NH3Pb(Sb)I3 solar cells

The crystal structures of perovskite CH3NH3Pb1− x Sb x I3 (x = 0 and 0.15) films in the solar cell configuration were studied by using Rietveld refinement. Optimizing atomic positions and site occupancies, satisfactory agreement was obtained between measured and calculated X-ray diffraction profiles. The refined composition ratio of metal, methylammonium (MA), and halogen was for the Sb-free solar cell. For the antimonized solar cell, this ratio was . The decreased MA occupancy in the antimonized solar cell was considered as a result of the compensation effect of the increased positive charge brought about by replacing Pb2+ with Sb3+.