Dual-mode emission optical temperature sensor and white light-emitting diodes using Ca2Mg0.01Y7.73Si6O26:0.24Bi3+, 0.02Eu3+ phosphors regulated by cation-controlled crystal fields

Efficient luminescent materials with dual functionalities for WLEDs and non-contact temperature sensing remain a challenge due to limitations in luminescence efficiency and tunability. This study addresses these challenges by engineering Ca 2 Y 8 Si 6 O 26 :Bi 3+ phosphors through strategic cation substitution (Ba 2+ , Mg 2+ , Lu 3+ , and Sc 3+ ) and Eu 3+ co-doping. The results reveal that cation substitution improves the crystal structure and enhances Bi 3+ ion luminescence intensity, while Eu 3+ doping introduces a red emission component, enabling single-component warm white light emission.The optimized phosphor composition, Ca 2 Y 7.76 Si 6 O 26 :0.24Bi 3+ , exhibits strong excitation at 332 nm and an emission peak at 499 nm. With Mg 2+ and Eu 3+ co-doping, Ca 2 Mg 0.01 Y 7.73 Si 6 O 26 :0.24Bi 3+ , 0.02Eu 3+ achieves dual-mode temperature sensing with high sensitivity values of 0.006 % (499 nm/422 nm) and 0.029 % (618 nm/422 nm). Additionally, colorimetric analysis demonstrates a tunable shift towards warm white light emission with increasing Eu 3+ concentrations.These findings underscore the potential of Ca 2 Mg 0.01 Y 7.73 Si 6 O 26 :0.24Bi 3+ , 0.02Eu 3+ phosphors as a scalable solution for advancing high-performance single-component WLEDs and dual-mode temperature sensors. This research provides a practical pathway to overcoming current limitations in solid-state lighting and temperature monitoring technologies.