1：Experimental Design and Method Selection:

The phosphors were synthesized using a traditional solid-state reaction method. The concentration-dependent optical properties were investigated, and the mechanism for luminescence enhancement via Mg2+ doping was studied.

2：Sample Selection and Data Sources:

Samples included CAZO:xMn4+ (x =

3：2%, 4%, 6%, 8%) and CAZO:

0.4%Mn4+,yMg2+ (y = 2%, 4%, 10%, 14%, 16%) phosphors. Starting materials were ZnO, Al2O3, CaCO3, MnCO3, and MgO with specified purities.

4：4%Mn4+,yMg2+ (y = 2%, 4%, 10%, 14%, 16%) phosphors. Starting materials were ZnO, Al2O3, CaCO3, MnCO3, and MgO with specified purities. List of Experimental Equipment and Materials:

3. List of Experimental Equipment and Materials: Equipment includes a powder X-ray diffractometer (Bruker D8 Advance), field-emission scanning electron microscope (FE-SEM; TESCAN MAIA3), Edinburgh FS5 spectrofluorometer with a 150 W Xenon lamp, pulsed Xenon lamp, integrating sphere, and temperature controller. Materials are ZnO (≥99.0%), Al2O3 (analytical reagent), CaCO3 (≥99%), MnCO3 (44.0-48.0% Mn), MgO (≥98%).

5：0%), Al2O3 (analytical reagent), CaCO3 (≥99%), MnCO3 (0-0% Mn), MgO (≥98%). Experimental Procedures and Operational Workflow:

4. Experimental Procedures and Operational Workflow: Starting materials were weighed, ground in an agate mortar, calcined in Al2O3 crucibles at 1000°C for 2 h and 1300°C for 6 h in air. XRD, FE-SEM, PL, PLE, decay lifetimes, IQE, and temperature-dependent PL spectra were measured.

6：Data Analysis Methods:

XRD patterns were compared with standard cards. PL and PLE spectra were analyzed. Decay lifetimes were fitted using exponential functions. IQE was calculated using an equation involving emission and excitation spectra. Activation energy was determined from temperature-dependent data using the Arrhenius equation.