Tunable multicolor luminescence and energy transfer in La₃SnGa₅O₁₄: Er³⁺, Sm³⁺ phosphors for optical thermometry and...

To achieve dual-function applications of high-sensitivity optical temperature measurement and anti-counterfeiting, a novel La₃SnGa₅O₁₄: Er³⁺, Sm³⁺ phosphor was successfully synthesized using high-temperature solid-state reaction. The structural characteristics, photoluminescence behavior, and energy transfer from Er³⁺ to Sm³⁺ were systematically studied. Tunable multicolor emission from green to orange-red was realized by adjusting Sm³⁺ doping concentrations and excitation wavelengths. Temperature-dependent luminescence evaluated through the fluorescence intensity ratio method demonstrated a maximum relative sensitivity of 4.496% K^-1 at 298 K. Additionally, the excitation-dependent luminescence characteristics were successfully demonstrated in prototype anti-counterfeiting patterns. These outcomes indicate that La₃SnGa₅O₁₄: Er³⁺, Sm³⁺ is a promising dual-function material capable of both sensitive temperature detection and advanced optical anti-counterfeiting.