An energy self-compensating phosphosilicate material applied to temperature sensors

Area of Science:

• Materials Science
• Solid-State Chemistry
• Luminescence

Background:

• Sustaining phosphor emission intensity at elevated temperatures is crucial for many optoelectronic applications.
• Emission loss at high temperatures is a significant challenge in phosphor development.
• Controlling energy transfer and trap dynamics is key to improving thermal stability.

Purpose of the Study:

• To develop a novel phosphosilicate phosphor with enhanced thermal stability.
• To investigate the mechanisms behind temperature-dependent luminescence in Ce³⁺ and Eu²⁺/Eu³⁺ co-doped materials.
• To explore the potential of this material for high-temperature sensing applications.

Main Methods:

• Synthesis of a multi-cationic site and lattice-distorted phosphosilicate phosphor (Ca₈Al₂P₆SiO₂₈:Ce, Eu).
• Analysis of temperature-dependent emission spectra, thermoluminescence curves, decay times, fluorescence characteristics, and cathodoluminescence spectra.
• Investigation of energy transfer mechanisms between Ce³⁺ and Eu²⁺/Eu³⁺ ions and the role of traps.

Main Results:

• The synthesized phosphor, Ca₈Al₂P₆SiO₂₈:Ce, Eu, demonstrates unique luminescence properties.
• Ce³⁺ luminescence shows consistent trends, while Eu²⁺/Eu³⁺ emission intensities vary significantly with temperature.
• Traps play a critical role in Ce³⁺ luminescence, and Ce³⁺ to Eu²⁺/Eu³⁺ energy transfer drives the abnormal luminescence of Eu ions.

Conclusions:

• The developed phosphosilicate phosphor exhibits self-suppression of emission loss through trap compensation and energy transfer.
• A high thermal sensitive fluorescence intensity ratio was achieved over a wide temperature range.
• This material shows significant promise for application in advanced temperature sensors.