1：Experimental Design and Method Selection:

A multistep route involving hydrothermal synthesis of TiO2 nanorod array (TNR) film, photochemical reduction for Ag deposition, and in situ oxidation with FeCl3 to form Ag@AgCl core-shell structures. The oxidation time was varied (15, 30, 60, 120 min) to study its effects.

2：Sample Selection and Data Sources:

FTO glass substrates were used; chemicals like tetrabutyl titanate, HCl, AgNO3, FeCl3 were analytical grade. Samples were prepared and characterized.

3：List of Experimental Equipment and Materials:

X-ray diffraction (XRD, MAC M18XHF), field emission scanning electron microscopy (FESEM, Hitachi S4800), transmission electron microscopy (TEM, JEM-2100), X-ray photoelectron spectroscopy (XPS, Thermo ESCALAB250), UV-Vis spectrophotometer (Shimadzu UV-2550), photoluminescence spectrophotometer (Hitachi F-4500), electrochemistry workstation (CHI 660D, Chenhua), Xe lamp (SS150A, ZOLIX).

4：Experimental Procedures and Operational Workflow:

Clean FTO substrates, hydrothermally grow TNR, immerse in AgNO3 under UV light for Ag deposition, oxidize with FeCl3 solution at pH 2.5 for different times, wash and dry films. Characterize structure and properties, perform photoelectrochemical tests in Na2SO4 electrolyte with three-electrode system, and photocatalytic degradation of methyl orange under visible light.

5：5 for different times, wash and dry films. Characterize structure and properties, perform photoelectrochemical tests in Na2SO4 electrolyte with three-electrode system, and photocatalytic degradation of methyl orange under visible light. Data Analysis Methods:

5. Data Analysis Methods: XRD for phase identification, SEM/TEM for morphology, XPS for composition, UV-Vis for absorbance, PL for charge recombination, photocurrent response and EIS for electrochemical properties, kinetic analysis for photocatalytic degradation rates.