An Overview of Luminescent Primary Thermometers

Extending the Palette of Luminescent Primary Thermometers: Yb3+/Pr3+ Co-Doped Fluoride Phosphate Glasses

“… 18 The S r values obtained for both PY14 and PY18 are ∼1.0% K –1 at T 0 ( Table S6 ), consistent with previously reported S r values for Pr 3+ . 53 − 55 The obtained samples present a δ T of 0.5 K at T 0 , in close correspondence with the primary luminescent thermometers reported for Yb 3+ /Er 3+ -containing materials (see Table 2 in ref ( 32 )).…”

“…Nonetheless, the number of primary luminescent thermometers reported to date remains scarce, with fewer than 20 examples, mainly involving Er 3+ /Yb 3+ co-doped materials. 32 Herein, we present, for the first time, a luminescent primary thermometer based on the thermally coupled levels of Pr 3+ . This novel approach is advantageous because (i) the recording of tedious calibration curves is not necessary and (ii) self-heating induced by the excitation source can be neglected.…”

Harnessing ligand design to develop primary and self-calibrated luminescent thermometers with field-induced single ion magnet behaviour in Dy3+ complexes

“…Primary luminescent thermometers eliminate the need for prior calibration procedures, a major advantage in luminescence thermometry. 51 Indeed, 2 ·CHCl 3 is the first example of a Dy 3+ primary luminescent thermometer based on the intensity ratio between transitions from the lowest energy state or second lowest energy state of the excited 4 F 9/2 level to the 6 H 15/2 ground state multiplet. 51 The other reported example of a Dy 3+ primary luminescent thermometer with slow magnetic relaxation operating in the presence of a magnetic field up to 3.6 T is based on the classical Mott–Seitz model.…”

“…Beyond Dy 3+ , primary luminescent thermometers have also been explored in Yb 3+ /Er 3+ -doped upconverting materials, 51–53 and Yb 3+ /Pr 3+ co-doped fluoride phosphate glasses. 54 This technique uses the ratio between the intensities arising from two thermally coupled levels of the Ln 3+ ions that are directly related to the absolute temperature, T , through a well-established equation:where k B is the Boltzmann constant, Δ E 2 is the energy gap between the barycenters of the thermally coupled levels (Fig.…”

“…Usually Δ E 2 and Δ ′ 0 are determined independently of the thermal calibration procedure, the first by a deconvolution procedure involving the emission spectra for determining the energy gap value and the second by an extrapolation of Δ ′ when external heating is negligible. 51…”