1：Experimental Design and Method Selection:

The study involved fabricating IAI multilayer films using DC reactive magnetron sputtering at room temperature, followed by the deposition of NiOx and WO3 electrochromic layers. A five-layer ECD structure (Glass/IAI/NiOx/LiClO4-PC-PMMA/WO3/IAI/Glass) was assembled using a polymer gel electrolyte. The methodology included characterization of optical, electrical, and electrochemical properties.

2：Sample Selection and Data Sources:

Glass substrates were used, cleaned ultrasonically in ethanol and deionized water. Samples included IAI films, NiOx/IAI, WO3/IAI, and the full ECD.

3：List of Experimental Equipment and Materials:

Equipment included DC magnetron sputtering system, ultrasonic cleaning machine, vacuum chamber, mass flow controllers, X-ray diffractometer (Bruker-AXS D8-Advance), SEM (JEOL JSM 7800F Prime, FEI Helios Nanolab600i), AFM (Veeco Dimension 3100), spectrometer (Bentham PVE 300), four-point probe (Signatone), electrochemical workstation (Chen Hua Instruments CHI 660E), UV-Vis spectrometer (Hitachi U-3010). Materials included ITO target (10% SnO2, 90% In2O3), Ag target (99.99% purity), Ni target, W target, propylene carbonate (PC), lithium perchlorate (LiClO4), polymethyl methacrylate (PMMA).

4：0). Materials included ITO target (10% SnO2, 90% In2O3), Ag target (99% purity), Ni target, W target, propylene carbonate (PC), lithium perchlorate (LiClO4), polymethyl methacrylate (PMMA). Experimental Procedures and Operational Workflow:

4. Experimental Procedures and Operational Workflow: Substrates were cleaned and placed in a vacuum chamber. IAI films were deposited sequentially: bottom ITO (50 nm), Ag (5 nm), top ITO (30 nm). NiOx and WO3 were deposited on IAI films. The polymer gel electrolyte was prepared and the ECD assembled in a vacuum autoclave at 80°C and 0.1 MPa. Characterization involved GI-XRD, XRR, SEM, AFM, optical transmittance/reflectance, electrical resistivity, CV, CA, and in-situ optical measurements.

5：1 MPa. Characterization involved GI-XRD, XRR, SEM, AFM, optical transmittance/reflectance, electrical resistivity, CV, CA, and in-situ optical measurements. Data Analysis Methods:

5. Data Analysis Methods: Data were analyzed using Bruker-EVA software, JC-PDF database, FullProf-Suite, Bruker-LEPTOS software, SCOUT software for optical modeling, and standard electrochemical formulas for charge density and diffusion coefficients.