1：Experimental Design and Method Selection:

Electrodeposition method was used to prepare Sm-doped Cu2O films. A three-electrode system was employed with FTO as the working electrode, Pt wire as the counter electrode, and Ag/AgCl as the reference electrode.

2：Sample Selection and Data Sources:

The electrodeposition solution consisted of

3：4 M copper sulphate (CuSO4), 3 M of lactic acid (C3H6O3), and different concentrations of samarium trichloride (SmCl3·6H2O). List of Experimental Equipment and Materials:

XRD (XPERT SOFTWAR) for structural analysis, EVO18 ZEISS SEM for morphological analysis, Princeton Acton SP 2500 for Raman spectroscopy, Lambda Perkin Elmer UV–Vis–NIR spectrometer for optical analysis, stylus profilometer for thickness measurement, spectroflurometer system for PL analysis, and Keithley source meter ?2450 model for I–V characterization.

4：Experimental Procedures and Operational Workflow:

The films were deposited at ?400 mV for 30 min with pH maintained at

5：Data Analysis Methods:

Structural parameters were calculated using Scherrer’s formula, strain and dislocation density were calculated using specific equations, and optical properties were analyzed using UV–Vis absorption spectra.