Highly sensitive optical thermometer of Sm³⁺, Mn⁴⁺ activated LaGaO₃ phosphor for the regulated thermal behavior

Abstract

Sm 3+ , Mn 4+ co-activated LaGaO 3 phosphors, giving the characteristic emissions of orange and red emission simultaneously, were prepared by a solid-state reaction. Their luminescence properties, energy transfer behavior, thermal stability, and ratiometric temperature sensing performance were investigated. Thanks to the inhibition of energy transfer between Sm 3+ and Mn 4+ ions at high temperature and the reconstruction of the traps, the distinct optical behavior of the involved activators dependent on the ambient temperature was evaluated. Antithermal quenching performance of Sm 3+ ions along with the emission declination of Mn 4+ ions was observed. Hence, the optical thermometry characteristics of the resultant phosphor based on the fluorescent intensity ratio (orange/red) realize a recorded temperature sensitivity of 4.19% K −1 and 2.09% K −1 . Moreover, the as-explored film combined with the LaGaO 3 : Sm 3+ , Mn 4+ phosphor is demonstrated to be a promising multi-color optical thermometer.

Improved optical thermometric sensitivity of Eu3+‐doped calcium niobate phosphor via nonstoichiometric control

“…Evidently, it is well fitted by the exponential formula: 40,41,42 $$$$\begin{equation}{\mathrm{FIR}} = \frac{{{I}_{{\mathrm{as}}}}}{{{I}_{\mathrm{s}}}} = A\exp \left( {\frac{{ - {E}_{\mathrm{a}}}}{{{k}_{\mathrm{B}}T}}} \right) + B\end{equation}$$$$where I as is the intensity of Eu 3+ ions, I s is the intensity of host, A is the proportional parameter, k B is the Boltzmann constant, B is the offset parameter, and E a is the activation energy. The absolute sensitivity ( S a ) defined as the average FIR change with respect to T , and the relative sensitivity ( S r ), defined as the rate of FIR change along with T , can be expressed as: 37,43 $$$$\begin{equation}{S}_{\mathrm{a}} = C\exp \left( {\frac{{ - {E}_{\mathrm{a}}}}{{kT}}} \right) \times \left( {\frac{{ - {E}_{\mathrm{a}}}}{{k{T}^2}}} \right)\end{equation}$$$$ …”

Double-deconvolution method for the separation of thermalised emissions from chromium-doped lanthanum gallate and its potential in luminescence-based thermometry

“…The narrow bandwidth is typical of emission from the 2 E state, whose energy is largely insensitive to D and hence to Cr-O vibrations. Stokes and anti-Stokes bands can be attributed to either side of the 2 E peak [30].…”

“…LGO-based phosphors have been investigated previously for thermometric behaviour. Mondal et al synthesised LGO:Cr 3+ thermometers with a maximum LIR relative sensitivity of 2.07% K -1 at 150 K, and a temperature resolution of 0.24 K. [3] The LGO: Nd 3+ thermometers reported by Back et al had a maximum LIR relative sensitivity of 1.59% K -1 at 300 K and temperature resolution of ~1.0 K. [4] The Mn 4+ ion, like Cr 3+ , is a d 3 ion and has also been explored for luminescence thermometry, Li et al having reported a LGO: Sm 3+ , Mn 4+ material with a maximum relative sensitivity of 2.09% K -1 at 456 K [30]. Alongside Nd 3+ , vanadium can be used in dual emission luminescence thermometers, taking advantage of its various oxidation states, as in LaGaO3:V, Nd 3+ phosphors reported by Kniec et al Relative sensitivities for the V 5+ , V 4+ , and V 3+ -containing samples were, respectively, 1.0% K -1 at 268 K and 363 K; 0.49% K -1 at -293 K; and 1.44% K -1 at 348 K [31].…”

Slow magnetic relaxation in Nd(iii) and Sm(iii) complexes formed in three-dimensional lanthanide-dicyanidometallate(i) frameworks exhibiting luminescent properties

“…A few studies have reported ratiometric thermometers for Sm(III) comprising phosphors. [69][70][71][72] Table 3 compares the reported sensitivities. SmAu in the broad T-range has good thermometric performance in comparison to other systems (Table 3) and a particularly good S r value for the low-temperature range.…”