Fig. 3: Photochemical reaction mechanism of patterning based on mix-halide perovskite films.
a The absorption, and b the photoluminescence spectrum of the MAPbBr3 perovskite film with the different methylammonium iodide (MAI) doping concentrations. c Commission Internationale de L’ Eclairage (CIE) coordinates of mix-halide perovskite films with the different MAI doping concentrations. d Photoluminescence photographs of mix-halide perovskite films with different MAI doping concentrations under different ultraviolet (UV) irradiation times. e The mechanism of the photoluminescence variation of mix-halide perovskite films with different MAI doping concentrations before and after UV irradiation. f Absorption spectra of the mix-halide perovskite films with MAI concentration of 0.1 mg/ml at different UV irradiation times. g Photoluminescence photographs and schematic diagram of mix-halide perovskite single crystals under different UV irradiation times, revealing phase separation and decomposition of iodine-rich phases. The top picture is the experimental data, and the bottom picture is the corresponding schematic diagram. h X-ray diffraction (XRD) pattern of the mix-halide perovskite film before and after UV irradiation. i Decomposition mechanism of mix-halide perovskite film under UV irradiation. j Microscopic ion distribution during phase separation and decomposition of mix-halide perovskite film. The gradient color arrows are added to increase the readability of Fig. 3 and have no physical properties.
