fig9

Figure 9. Morphologies and optical properties of 2D alternating cations in the interlayer space (ACI) phase perovskite single crystals. SEM images of (A) (GA)(MA)_nPb_nI_3n+1 (n = 1-3) and (B) (BEA)_0.5MA₃Pb₃I₁₀ crystals. Reprinted with permission from ref.^[23,61]: Copyright 2017, American Chemical Society; Copyright 2019, Wiley-VCH GmbH. (C) XRD result of the (GA)(MA)₂Pb₂I₇ single crystal. Reprinted with permission from ref.^[27]: Copyright 2023, Elsevier. (D) PL and (E) TRPL spectra of (GA)(MA)_nPb_nI_3n+1 (n = 1-3); ACI1 (n = 1), ACI2 (n = 2), and ACI3 (n = 3) perovskites, and (F) schematic illustration of exciton dynamics in ACI phases. Reprinted with permission from ref.^[60]: Copyright 2021, American Chemical Society.