1：Experimental Design and Method Selection:

The study employed plasma-enhanced atomic layer deposition (PEALD) to deposit Al2O3 on CsPbBr3 NCs films for encapsulation, comparing it with thermal atomic layer deposition (TALD). The rationale was to use PEALD for denser and more efficient film growth at low temperatures to protect the NCs from environmental degradation.

2：Sample Selection and Data Sources:

CsPbBr3 NCs were synthesized using lead bromide, cesium carbonate, 1-octadecene, oleic acid, and oleylamine. Films were spin-coated on glass substrates. Samples included pristine NCs films and those coated with Al2O3 via PEALD or TALD.

3：List of Experimental Equipment and Materials:

Equipment included a PEALD system (Jiaxing Ke-micro Technology), TEM (JEM-2100), SEM (JSM 6701F), UV-VIS-NIR spectrometer (Lambda 750S), spectrofluorometer (Edinburgh instruments FS5), XPS (ESCALAB 250Xi), and spectroscopic ellipsometry. Materials included PbBr2 (99.999%, YingKou YouXuan Trade Co. Ltd.), Cs2CO3 (99.999%, Macklin), ODE (90%, Macklin), OA (90%), OAm (90%, ShangHai D&B Biological Science and Technology Co. Ltd.), TMA, and O2 plasma.

4：999%, YingKou YouXuan Trade Co. Ltd.), Cs2CO3 (999%, Macklin), ODE (90%, Macklin), OA (90%), OAm (90%, ShangHai D&B Biological Science and Technology Co. Ltd.), TMA, and O2 plasma. Experimental Procedures and Operational Workflow:

4. Experimental Procedures and Operational Workflow: NCs synthesis involved degassing and heating reactants, injection, cooling, precipitation, and centrifugation. Films were spin-coated at 2000 rpm for 40s. Al2O3 deposition was done at 50°C with specific cycle parameters for PEALD (TMA and O2 plasma) and TALD (TMA and H2O). Characterization included TEM, SEM, absorption spectra, PLQY measurements, XPS, and stability tests under ambient conditions, water immersion, and UV light.

5：0s. Al2O3 deposition was done at 50°C with specific cycle parameters for PEALD (TMA and O2 plasma) and TALD (TMA and H2O). Characterization included TEM, SEM, absorption spectra, PLQY measurements, XPS, and stability tests under ambient conditions, water immersion, and UV light. Data Analysis Methods:

5. Data Analysis Methods: Data were analyzed using standard techniques for microscopy, spectroscopy, and XPS to assess film morphology, optical properties, and elemental composition. Stability was evaluated by monitoring PLQY over time.