Fig. 3
From: Understanding how excess lead iodide precursor improves halide perovskite solar cell performance
GIWAXS 2D patterns for control-HaP (a–c) and w/-PbI2-HaP (d–f) at different X-ray grazing-incidence angles such as 0.15°(a) and (d), 0.20°(b) and (e), and 0.3° (c) and (f), measured at 11.6 keV for 10 s. Peaks A, B, C, D, E, and F are assigned to α[100]cubic, α[200]cubic, α[210]cubic, α[100]trigonal of PbI2, δ[100]hexagonal, and δ[002]hexagonal in this HaP film, respectively
