Fig. 2: Structural characterization of mixed-halide perovskite thin films.
From: Local halide heterogeneity drives surface wrinkling in mixed-halide wide-bandgap perovskites
Grazing-incidence wide-angle X-ray scattering (GIWAXS) patterns of perovskite films with different compositions. a {x/y} = 0.25|0.40. b {x/y} = 0.50|0.40. c {x/y} = 0.75⁞0.40. d {x/y} = 0.25|0.50. e {x/y} = 0.50¦0.50. f {x/y} = 0.75⁞0.50. g {x/y} = 0.25¦0.60. h {x/y} = 0.50⁞0.60. i {x/y} = 0.75⁞0.60. The peaks corresponding to unreacted PbI2 (q ≈ 0.9 Å−1) and the (100) plane of the perovskite (q ≈ 1.0 Å−1) are marked in (a). Azimuthal intensity profiles of the main Debye-Scherrer ring (100) as a function of χ angle from GIWAXS for perovskite compositions with varying MA and Br contents. j 25% MA. k 50% MA. l 75% MA. The data in j–l have been vertically offset for clarity. Smooth films show ring-like features for the (100) plane at q ≈ 1.0 Å−1 whereas films with increasing roughness show intense spots corresponding to preferential orientation.
