1：Experimental Design and Method Selection:

The study synthesized ceramics via solid-state reaction to investigate the effects of B-site Mo6+ substitution on UCL and ferroelectric properties in Er3+-doped SBN. Rietveld refinement was used for structural analysis, UCL spectra were measured under NIR excitation, and dielectric and ferroelectric properties were characterized using standard techniques.

2：Sample Selection and Data Sources:

Polycrystalline ceramics of SBN-Ax and SBN-Bx with varying Mo6+ concentrations (x = 0, 0.03, 0.06, 0.1) were prepared. Raw materials included SrCO3, BaCO3, Nb2O5, Er2O3, and MoO3 from specified suppliers.

3：03, 06, 1) were prepared. Raw materials included SrCO3, BaCO3, Nb2O5, Er2O3, and MoO3 from specified suppliers. List of Experimental Equipment and Materials:

3. List of Experimental Equipment and Materials: X-ray powder diffractometer (Bruker D8 Advanced), Zolix SBP300 spectrometer, dielectric spectrometer (TH2828S, Tonghui Electronic Co. Ltd.), radiant precision multiferroic tester (Premier II, Radiant Technologies Ltd.), agate pots and balls, planetary mill.

4：Experimental Procedures and Operational Workflow:

Mixtures were milled, dried, calcined at 1300°C, pelletized, sintered at 1350°C, polished to 0.5 mm thickness. XRD patterns collected, UCL spectra measured at 980 nm excitation, dielectric properties measured from 290 to 580 K, ferroelectric loops measured at room temperature.

5：5 mm thickness. XRD patterns collected, UCL spectra measured at 980 nm excitation, dielectric properties measured from 290 to 580 K, ferroelectric loops measured at room temperature. Data Analysis Methods:

5. Data Analysis Methods: Rietveld refinement using GSAS program, analysis of UCL intensity ratios, temperature sensing via fluorescence intensity ratio method, dielectric permittivity and ferroelectric hysteresis loop analysis.