Ratiometric optical thermometry based on temperature-induced shift of V-O charge transfer band edge

Area of Science:

• Materials Science
• Optical Physics
• Solid-State Chemistry

Background:

• Ratiometric optical thermometry offers non-contact temperature measurement.
• Luminescent materials are crucial for optical thermometry applications.
• Yttrium vanadate (YVO4) doped with rare-earth ions is a promising host for thermometry.

Purpose of the Study:

• To develop a ratiometric optical thermometer based on YV_1-xP_xO₄:Tb³⁺, Eu³⁺/Sm³⁺.
• To investigate the temperature-induced spectral shifts and emission variations.
• To achieve high sensitivity and accuracy in temperature sensing.

Main Methods:

• Synthesis of YV_1-xP_xO₄ solid solutions with varying P content.
• Characterization of material structure and luminescent properties.
• Temperature-dependent emission spectra measurements under 352 nm excitation.
• Analysis of fluorescence intensity ratios for thermometry.

Main Results:

• Successful formation of YV_1-xP_xO₄ solid solution enhancing Tb³⁺ emission.
• Observed opposite temperature dependences between Tb³⁺ and Eu³⁺/Sm³⁺ emissions.
• Achieved high relative sensitivity of 2.85% K^-1 around 365 K.
• Demonstrated potential for accurate optical temperature sensing.

Conclusions:

• The designed ratiometric optical thermometry strategy is effective.
• YV_1-xP_xO₄:Tb³⁺, Eu³⁺/Sm³⁺ is a promising material for optical temperature sensing.
• The combined V-O charge transfer band shift and rare-earth ion emission variations enable high sensitivity.