1：Experimental Design and Method Selection:

The study used the sol-gel spin-coating method to fabricate Fe-doped V2O5 films with varying Fe atomic percentages (0.0, 0.5, 1.0, and 1.5 at%). The rationale was to optimize doping for improved electrochromic properties. Theoretical models included XRD for structural analysis, XPS for chemical binding states, and electrochemical measurements for performance evaluation.

2：0, 5, 0, and 5 at%). The rationale was to optimize doping for improved electrochromic properties. Theoretical models included XRD for structural analysis, XPS for chemical binding states, and electrochemical measurements for performance evaluation. Sample Selection and Data Sources:

2. Sample Selection and Data Sources: Samples were prepared on FTO glass substrates. Precursors included vanadium oxide (V2O5), polyvinylpyrrolidone (PVP), hydrogen peroxide (H2O2), and iron(III) chloride hexahydrate. Data were sourced from laboratory measurements using specified equipment.

3：List of Experimental Equipment and Materials:

Equipment included X-ray diffractometer (XRD, Rigaku D/MAX2500V), X-ray photoelectron spectrometer (XPS, AXIS ultra-delay line detector with Al Kα source), field-emission scanning electron microscope (FE-SEM, Hitachi S-4800), hall-effect measurement system (Ecopia, HMS-3000), ultraviolet-visible spectrophotometer (UV-vis, Perkin-Elmer Lambda-35), and potentiostat/galvanostat (PGSTAT302N, FRA32M, Metrohm Autolab B.V.). Materials included V2O5 (Alfa Aesar), PVP (Aldrich), H2O2 (Junsei), iron(III) chloride hexahydrate, FTO glass (Pilkington), and LiClO4 electrolyte.

4：Experimental Procedures and Operational Workflow:

Precursor solutions were prepared by dissolving V2O5 and PVP in DI water with H2O2, adding Fe dopant at specified percentages. Spin-coating was performed at 2000 rpm for 30 s on FTO substrates, followed by annealing at 500°C for 1 h in air. Characterization involved XRD, XPS, FE-SEM, electrical conductivity measurements, UV-vis spectroscopy, and electrochemical tests in a three-electrode cell with Pt counter electrode and Ag reference electrode.

5：Data Analysis Methods:

Data were analyzed using techniques such as XRD peak identification, XPS peak fitting, SEM image analysis, calculation of optical band gap from UV-vis data using Tauc plot method, and determination of Li+ diffusion coefficient from CV data using the Randles-Sevcik equation.