1：Experimental Design and Method Selection:

The study involved the fabrication of MA0.4FA0.6BaxPb1-xIyCl3-y films with various barium doping concentrations using a solvent engineering method. The surface morphology, crystal orientation, and optical properties of these films were investigated. In-situ GIWAXS was used to analyze the heating crystallization process.

2：4FA6BaxPb1-xIyCl3-y films with various barium doping concentrations using a solvent engineering method. The surface morphology, crystal orientation, and optical properties of these films were investigated. In-situ GIWAXS was used to analyze the heating crystallization process. Sample Selection and Data Sources:

2. Sample Selection and Data Sources: Perovskite precursor solutions were prepared with different concentrations of barium iodide (BaI2) and other chemicals. The films were characterized using FE-SEM, AFM, GIWAXS, UV-vis spectroscopy, PL spectra, and time-resolved PL characterization.

3：List of Experimental Equipment and Materials:

FE-SEM (su8010, HITACHI), AFM (Dimension-3100 Multimode, Digital Instruments), synchrotron X-ray spectroscopy (λ ~ 1.0256 ?) on beamline 23A and 13A1 of the NSRRC, UV-vis spectrometer (V-730, Jasco), Keithley 2400 meter for J-V performance measurement.

4：0256 ?) on beamline 23A and 13A1 of the NSRRC, UV-vis spectrometer (V-730, Jasco), Keithley 2400 meter for J-V performance measurement. Experimental Procedures and Operational Workflow:

4. Experimental Procedures and Operational Workflow: The perovskite precursor solution was coated onto mesoporous zinc-doped TiO2 at specific spin-coating speeds, followed by anti-solvent treatment and annealing. The spiro-OMeTAD precursor solution was then spin-coated onto the perovskite film, and a gold electrode was thermally evaporated.

5：Data Analysis Methods:

The data from GIWAXS, UV-vis spectroscopy, PL spectra, and J-V measurements were analyzed to determine the crystallinity, bandgap, charge carrier dynamics, and photovoltaic performance of the perovskite films.