Dy3+-doped yttrium complex molecular crystals for two-color thermometry in heterogeneous materials

Abstract

We develop Dy 3+ -doped yttrium complexes for use as two-color thermometry (TCT) phosphor molecular crystals in heterogeneous materials. These complexes include: Dy:Y(acac)3(phen), Dy:Y(hfa)3(DPEPO), Dy:Y(4-BBA)3(TPPO), Dy:Y(acac)3, and Dy:Y(acac)3(DPEPO), where the Dy/Y ratio is 1:9. We characterize the materials' photoluminescence at different temperatures to determine the TCT calibration parameters and the degree to which thermal quenching influences the emission. From this data we observe a link between the excited state lifetime at room temperature and the degree to which the material is susceptible to thermal quenching (i.e. materials having long room temperature lifetimes are more resistant to thermal quenching than materials with short room temperature lifetimes). Of the five complexes tested we find that Dy:Y(acac)3(DPEPO) has the best thermal performance, with the most likely source of improvement being DPEPO's compact rigid structure. This rigidity helps with energy transfer to the Dy 3+ ion, suppresses non-radiative loss modes, and reduces exciplex formation.

A Luminescent Thermometer Exhibiting Slow Relaxation of the Magnetization: Toward Self-Monitored Building Blocks for Next-Generation Optomagnetic Devices

“…Here, back-ET is enhanced by the increased population of the Dy III 4 I 15/2 level, which is thermally coupled with the 4 F 9/2 level. Such coupling is usually employed in Dy III -based luminescent thermometers at high temperature. ,,, However, only a weak signal ascribed to the 4 I 15/2 → 6 H 15/2 transition was detected (marked with ** in Figure a–c), the intensity of which decreases as the temperature increases. This behavior stems from an energy difference between the Dy III 4 I 15/2 level and T 1 of only 1150 cm –1 , a situation that favors, particularly at high temperature, back-ET to tfaa – over radiative de-excitation to Dy III lower states.…”

“…The concept of luminescence thermometry has been widely applied in Ln III -doped inorganic materials − and metal–organic frameworks (MOFs). − Recently, molecular Ln III compounds acting as luminescent thermometers have also attracted much interest. − In this regard, SMM-based luminescence thermometry is yet to be reported. Herein, we present a unique dual-functional {Dy 2 } complex bearing SMM properties while simultaneously being a molecular luminescent thermometer.…”

Structural, luminescence and thermometric properties of nanocrystalline YVO4:Dy3+ temperature and concentration series

“…In comparison with Er 3+ , Tm 3+ or Nd 3+ ions, dysprosium ions are relatively rare utilizing for temperature sensing. Among other Dy 3+ single doped materials, the obtained S r values are comparable to the values reported in the literature: 1.7% K −1 for BaYF 5 :Dy 3+ NPs 80 , 1.6% K −1 for Gd 2 Ti 2 O 7 :Dy 3+ NPs 81 , 1.7% K −1 for YAG:Dy 3+ microcrystals 82 , 1.7% K −1 and 1.3% K −1 for Dy:Y(acac) 3 and Dy:Y(acac) 3 (phen) molecular crystals, respectively 83 .…”

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.…”