Constructing ultra-sensitive dual-mode optical thermometers: Utilizing FIR of Mn⁴⁺/Eu³⁺ and lifetime of Mn⁴⁺ based on double perovskite tellurite phosphor

Abstract

A strategy of optical temperature sensing was developed by using various thermal quenching of Mn4+ and Eu3+ for double perovskite tellurite phosphor in optical thermometers. Herein, SrGdLiTeO6 (SGLT): Mn4+,Eu3+ phosphors were synthesized by a high-temperature solid-state reaction method. The temperature-dependent emission spectra indicated that two distinguishable emission peaks originated from Eu3+ and Mn4+ exhibited significantly diverse temperature responses. Therefore, optical thermometers with a dual-mode mechanism were designed by employing a fluorescence intensity ratio (FIR) of Mn4+ (2Eg→4A2g) and Eu3+ (5D0→7F1,2) and the decay lifetime of Mn4+ as the temperature readouts. The temperature sensing of the phosphors ranging from 300 to 550 K were studied. The maximum relative sensitivities (Sr) are obtained as 4.9% K−1 at 550 K. Meanwhile, the 695 nm emission of Mn4+ possessed a temperature-dependent decay lifetime with Sr of 0.229% K−1 at 573 K. Relevant results demonstrate the SrGdLiTeO6:Mn4+, Eu3+ phosphor as an optical thermometer candidate and also provide constructive suggestions and guidance for constructing high-sensitivity dual-mode optical thermometers.

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

“…Obviously, the S a value of LGO: Sm 3+ , Mn 4+ phosphor shows an increasing trend in the temperature range of 373-473 K and reaches maximum at 456 K, which suggests a highly sensitive optical thermometer compared with other available phosphors (Table S2). [39][40][41][42] Herein, an as-explored transparent PDMS film combined with the optimized LGO: Sm 3+ , Mn 4+ sample is illustrated in Figure 5G. Primarily, the emission intensity of LGO: 0.01Sm 3+ , 0.001Mn 4+ sample and the corresponding phosphor embedded PDMS film shows insignificant change of the PL intensity for the advantage of the optical transparency of the PDMS and shown in Figure S7.…”

Ratiometric Thermometry Using Thermochromic Tb3+:Mn4+:Na4Mg(WO4)3 Phosphors

“…A commonly used approach to these phosphors is to activate a given host by codoping it with a trivalent rare-earth metal and a transition metal. ,− This strategy exploits the fact that emissions from d – d transitions are more prone to thermal quenching than those arising from their f – f counterparts. ,, Mn 4+ is one of the transition-metal ions that has been coupled to rare-earths to realize dual-activator ratiometric thermometers. Examples of rare-earth­(III)–manganese­(IV) pairs reported in the literature include Sm 3+ –, Eu 3+ –, − Tb 3+ –, ,, Dy 3+ –, , Ho 3+ –, and Er 3+ –Mn 4+ . These have been doped into a variety of hosts, including garnets, , double perovskites, − , aluminates, and orthoaluminates .…”

“…Examples of rare-earth­(III)–manganese­(IV) pairs reported in the literature include Sm 3+ –, Eu 3+ –, − Tb 3+ –, ,, Dy 3+ –, , Ho 3+ –, and Er 3+ –Mn 4+ . These have been doped into a variety of hosts, including garnets, , double perovskites, − , aluminates, and orthoaluminates . An expansion of the library of host materials for rare-earth­(III)–manganese­(IV) pairs is a desirable goal from the standpoint of developing novel thermosensitive phosphors.…”

Energy transfer-triggered multicolor emissions in Tb3+/Eu3+-coactivated Y2Mo3O12 negative thermal expansion microparticles for dual-channel tunable luminescent thermometers

“…Thus, the lifetime of Tb 3+ ions in YMO:Tb 3+ compounds is proved to be 870.7 μs. However, with introducing the Eu 3+ ions, the recorded decay curves of YMO:Tb 3+ /2xEu 3+ NTE microparticles (x > 0) diverge from the single exponential decay mode and they can only be fitted by using a non-exponential decay mode, as presented below: 16,31 (4) =…”

“…13 Apart from these, this above technique was also employed to investigate the temperature sensing capacity of other compounds, such as LiTaO 3 :Ti 4+ /Eu 3+ (S a = 0.671 K -1 ; S r = 5.425% K -1 ), Lu 3 Al 5 O 12 :Ce 3+ /Mn 4+ (S r = 4.37% K -1 ), SrGdLiTeO 6 :Mn 4+ /Eu 3+ (S r = 4.9% K -1 ), NaLuF 4 :Eu 3+ @g-C 3 N 4 (S a = 0.0057 K -1 ; S r = 0.455% K -1 ), etc. [14][15][16][17] Notably, when the FIR strategy based on dual-emitting centers is adopted, one obtains superior S a and S r values in rare-earth ions coactivated luminescent materials, implying that the adoption of the various thermal responses of dual-emitting centers is an efficient route to achieve high thermometric properties.…”