Fig. 1. (Color online) (a) Schematic structures for CsPbI₃ phases. Reproduced with permission^[15], Copyright 2015, Royal Society of Chemistry. (b) Structures for FA (top) and DMA (bottom) cations. Reproduced with permission^[25], Copyright 2018, Nature Publishing Group. (c) Schematic for crystal structure evolution from precursor solution toγ-CsPbI₃ and possible chemical interaction. Reproduced with permission^[21], Copyright 2022, Wiley. (d) Schematic for vacuum-assisted thermal annealing of CsPbI₃ film. (e) The conversion of 1D DMAPbI₃ film to 3D CsPbI₃ through cations exchange between Cs⁺ and DMA⁺. Reproduced with permission^[1], Copyright 2022, Wiley.

Fig. 2. (Color online) (a) TGA curves for DMAI, DMAPbI₃ powders and the powder scratched from the precursor film of CsI+PbI₂+DMAI. (b) GIWAXS forβ-CsPbI₃ films. Reproduced with permission^[32], Copyright 2019, AAAS. (c) Schematic for black-phase CsPbI₃ formation by using DMAI additive. Reproduced with permission^[33], Copyright 2019, Wiley. (d) Schematic for 2-TBA condensation reaction (top) and 3-TBA without condensation reaction (bottom); schematic for DMA⁺ removal by H₂O from the condensation reaction. Reproduced with permission^[36], Copyright 2022, American Chemical Society.