1：Experimental Design and Method Selection:

The study involves the addition of PBTI in the antisolvent treatment step during perovskite film deposition to investigate its effect on grain boundary passivation.

2：Sample Selection and Data Sources:

CsFAMA mixed cation precursors were used to fabricate high-quality perovskite films.

3：List of Experimental Equipment and Materials:

Materials include anhydrous N,N-dimethylformamide (DMF), anhydrous dimethyl sulfoxide (DMSO), anhydrous isopropanol (IPA), anhydrous chlorobenzene (CB), cesium iodide (CsI), zirconium(IV) acetylacetonate (ZrAcac), lead (II) iodide (PbI2), lead (II) bromide (PbBr2), methylammonium bromide (MABr), formamidinium iodide (FAI), and PCBM. Equipment includes a Keithley 2400 sourcemeter, Oriel Sol3A solar simulator, TESCAN MIRA3 for SEM, Helios Nanolab 600i FIB and FEI Talos TEM for STEM and EDX mapping, BRUKER ECO D8 series for XRD, FS5 spectrofluorometer for PL, Zahner IM6e electrochemical station for EIS, and ExciPro XL Femtosecond Transient Absorption Pump-Probe Spectrometer for TAS.

4：Experimental Procedures and Operational Workflow:

PSCs were fabricated with a structure of ITO/NiOx/perovskite/PCBM/ZrAcac/Ag. The perovskite layers were fabricated using a one-step antisolvent recipe with CB or PBTI in CB as antisolvents.

5：Data Analysis Methods:

The performance of PSCs was characterized by J-V measurements, EQE measurements, and stability tests under illumination. The morphology and crystallinity of perovskite films were analyzed by SEM, STEM, EDX mapping, XRD, and GIWAXS. The defect passivation and recombination losses were investigated by PL, TRPL, TAS, and EIS.