1：Experimental Design and Method Selection:

A fully automated spray-coated technology with ultrathin-film purification (UFP) was developed to build high-quality colloidal CsPbI3 QD thin films. The short-chain ligand of PTABr was introduced to partially substitute for the long-chain ligands to enhance carrier charge mobility and passivate vacancy defects.

2：Sample Selection and Data Sources:

Colloidal CsPbI3 perovskite QDs were synthesized by the conventional hot-injection method with some modification. Methyl acetate (MeOAc) was utilized as an effective antisolvent to remove the excess ligands and octadecene solvent.

3：List of Experimental Equipment and Materials:

Materials included PbI2, Cs2CO3, oleylamine, methyl acetate, hexane, oleic acid, octane, phenyltrimethylammonium bromide, titanium diisopropoxide bis(acetylacetonate), and chlorobenzene. Equipment included a transmission electron microscope, X-ray diffractometer, atomic force microscope, scanning electron microscope, and various spectrometers.

4：Experimental Procedures and Operational Workflow:

The QD solution was centrifuged to remove impurities, dried, and dispersed in octane. The solution was sprayed onto substrates using a mist nozzle with nitrogen gas. The UFP method involved spraying Pb(NO3)2 in MeOAc solution and neat MeOAc to remove residual ligands, followed by drying with an air blade.

5：Data Analysis Methods:

The crystal structure was determined by X-ray diffraction. Morphologies were investigated by SEM and TEM. Photophysical characteristics were examined using UV–vis and PL spectra. The performance of solar cells was measured using a digital source meter under simulated sunlight.