Sr8MgSc(PO4)7:Eu2+ phosphor: d–f transition driven applications for solid-state lighting and extreme environment multimode sensing investigations†

Abstract

Materials with multiple modes for measuring extreme environmental indicators are urgently required. Herein, a kind of bright yellow-green emitting phosphor Sr₈MgSc(PO₄)₇:Eu²⁺ with applications in solid-state luminescence and multi-mode sensing in extreme environments has been synthesized. The assembled warm white LED device has a higher color rendering index (R_a = 93.2), a lower correlated color temperature (CCT = 4718 K) and appropriate chromaticity coordinates (0.3509, 0.3397). Furthermore, from room temperature (RT, 298 K) to 78 K, the emission color rapidly changes from yellow-green to orange. The maximum relative sensitivity and absolute sensitivity were calculated as S_a (max) = 6.36 × 10⁻² K⁻¹ and S_r (max) = 1.8% K⁻¹, respectively. In the process of applying pressure, the phosphor withstands a pressure of up to 21.5 GPa. The calculation method of its pressure sensitivity is developed by using three strategies. The sensitivity obtained by the LIR method is the largest, which is S_pr (max) = 116.22% GPa⁻¹. In conclusion, the bright yellow-green phosphor Sr₈MgSc(PO₄)₇:Eu²⁺, showing a rapid and sensitive temperature and pressure response, has considerable potential for application in solid state lighting, low temperature sensing, and pressure sensing.