Two-color thermosensors based on [Y $$_{1-x}$$ 1 - x Dy $$_x$$ x (acetylacetonate) $$_3$$ 3 (1,10-phenanthroline)] molecular crystals

Abstract

We develop a two-color thermometry (TCT) phosphor based on [Y1−xDyx(acetylacetonate)3(1,10-phenanthroline)] ([Y1−xDyx(acac)3(phen)]) molecular crystals for use in heterogeneous materials. We characterize the optical properties of [Y1−xDyx(acac)3(phen)] crystals at different temperatures and Dy concentrations and find that the emission is strongly quenched by increasing temperature and concentration. We also observe a broad background emission (due to the ligands) and find that [Y1−xDyx(acac)3(phen)] photodegrades under 355 nm illumination with the photodegradation resulting in decreased luminescence intensity. However, while decreasing the overall emission intensity, photodegradation is not found to influence the integrated intensity ratio of the 4 I 15/2 → 6 H 15/2 and 4 F 9/2 → 6 H 15/2 transitions. This ratio allows us to compute the temperature of the complex Based on the temperature dependence of these ratios we calculate that [Y1−xDyx(acac)3(phen)] has a maximum sensitivity of 1.5 % K −1 and our TCT system has a minimum temperature resolution of 1.8 K. Finally, we demonstrate the use of [Y1−xDyx(acac)3(phen)] as a TCT phosphor by determining a dynamic temperature profile using the emission from [Y1−xDyx(acac)3(phen)].

Spectroscopic Signatures of Sub-Second Laser-Calcined Dy3+-Doped Oxide Precursors for Use in ex Situ Thermal Impulse Sensors

“…With the three host materials described we now provide a brief overview of Dy 3+ ’s optical properties. Dy 3+ is a well-characterized lanthanide ion used in many different applications for its optical properties, such as lasers, − two-color thermometry, − photocatalysts, and LEDs. ,,,,− It is most readily excited using wavelengths in the UV or blue spectral regime with its main visible emission lines occurring at approximately 480, 573, and 660 nm. Figure shows an approximate Dy 3+ energy level diagram with the primary transitions shown and labeled with their wavelengths.…”