1：Experimental Design and Method Selection:

The study involved the fabrication of α-Fe2O3 nanorod arrays with a TiO2 overlayer via a solution-based procedure followed by annealing in air. The methodology included Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray absorption near edge structure (XANES), and transient absorption spectroscopy (TAS) for characterization.

2：Sample Selection and Data Sources:

β-FeOOH nanorod arrays grown on FTO substrates were used as the starting material, which were then transformed into α-Fe2O3/TiO2 nanorod films.

3：List of Experimental Equipment and Materials:

Equipment included a PANalytical X’pert MPD Pro diffractometer, JEOL 7800F SEM, FEI Tecnai G2 F30 TEM, Kratos spectrometer (AXIS Ultra DLD) for XPS, and a Quantronix-designed femtosecond transient absorption laser system for TAS. Materials included ferric chloride hexahydrate, sodium nitrate, tetrabutyltitanate (TBT), and FTO glass.

4：Experimental Procedures and Operational Workflow:

The process involved growing β-FeOOH nanorod arrays, immersing them in TiO2 sol, ultrasonication, rinsing with ethanol, and annealing to transform into α-Fe2O3/TiO2 nanorod films.

5：Data Analysis Methods:

Data were analyzed using global fitting procedures for transient absorption decay profiles, and XANES spectra were analyzed to understand the electronic structure changes.