Photoluminescence and ratiometric fluorescence temperature sensing abilities of zincate phosphors
Introduction
As a rudimentary variable, temperature plays a substantial role in meteorology, agriculture, as well as military fields [[1], [2], [3], [4], [5]]. Different from conventional contact thermometer, optical non-invasive thermometry with excellent luminescence signal detection and celerity response is more adaptive to brutal surroundings like rapid moving objects, and hyperfine sized surfaces [6,7]. Compared with other temperature measurements based on the material's fluorescence property, such as emission bandwidths [8], emission lifetime [9], spectrum phase shift and so on [10], fluorescence intensity ratio (FIR) is prioritized to be utilized in the temperature sensing field for its intrinsic merit of being insusceptible to non-temperature factors.
To date, considerable attention has been focused on the rare-earth (RE) ion systems as their abundant and available 4f–4f transitions that are sensitive to temperature [[11], [12], [13]]. Due to the innate boundedness of low accuracy, indistinct sensitivity and ordinary signal discriminability aroused from the small energy gap (200 cm−1≤ΔE≤2000 cm−1) between the thermally coupled levels, luminescent ratiometric technology based on thermally coupled level pairs of lanthanide ions has been gradually faded [[14], [15], [16]]. Some previous works also reported the single transition metal (TM) Mn4+/Cr3+ doped phosphors by utilizing the FIR of forbidden and allowed transitions between 2E→4A2 and 4T2→4A2 as the temperature measurement criterion. The thermal sensitivity of such a system depends on the parabola's distortion belonging to the ground and excited states, which could be influenced by the crystal field strength. The susceptibility to thermal quenching, however, is restricted by the population of electrons in these two levels identifying with Boltzmann's law. Therefore, the intrinsic limitation of the maximum sensitivity stimulates us to work on the optical materials with dual luminescent centers [2]. So far, the FIR strategy-based materials have been tremendously investigated, including sole RE or TM ion combined with self-reference host [17], dual-emitting nanoscale temperature sensors base on co-doped dual RE ions or RE/TM ions [18,19], RE/quantum-dots hybrid nanostructures [20], dual luminescent centers of single lanthanide ion located at different crystal sites, and optical material containing different valences of doping RE ion [21].
In this article, we approached the neo-coactivated optical material involving dual TM ions with disparate temperature variations Ca14Al10Zn6O35:Ti4+,Mn4+, which can be abbreviated to CAZO: Ti4+,Mn4+. By adopting the variation of relatively temperature-susceptible Ti4+ emission intensity as the temperature detecting signal while the temperature-unimpressionable Mn4+ as the reference one, and in the absence of RE ions, Ca14Al10Zn6O35:Ti4+,Mn4+ phosphor with the advantages of being environmentally friendly and economically rationally is supposed to obtain a high temperature sensitivity. Although the Ti4+-activated phosphors were scarcely reported due to the unstable luminescence performance resulted from its naked 3d electron orbit (3d0), free from the inherent disadvantage of photon re-absorption phenomenon in RE ions, studies have proved that Ti4+ ion provides a broad emission range from ultraviolet to blue and can act as an excellent sensitizer ion to optimize the activator's luminescence property [4,22,23]. Meanwhile, due to the particular 3d3 electronic configuration, Mn4+ exhibited both outstanding thermal resistances resulted from strong electron-phonon coupling together with the existence of anti-Stokes, and high susceptibility to the coordination surroundings, especially the crystal field strength [[24], [25], [26]]. In addition, the zincate compound Ca14Al10Zn6O35 has already been corroborated as a splendid octahedral substrate for single-phase phosphors [22,[27], [28], [29]].
Hereby, the thermal sensitivity of such dual TM doped system highly relies on the distortion of the parabolas of the ground and excited states, caused by the influence of the crystal field strength. Benefitting from activator's sensibility to strong field strength, anti-Stokes phenomenon, and energy transfer from sensitizer to the activator, the thermal properties of doped ions vary, thus a high absolute sensitivity has been obtained as 3.79% K−1. What is more, Mn4+ ion displayed a well-separated photoluminescence band originating from spin-forbidden 2E→4A2 transition from the emission peak of Ti4+, providing an excellent signal discriminability and accurate temperature detection. Together with the outstanding thermal fatigue resistance, it is concluded that this novel dual activators-based optical thermometric material in the absence of RE ions is a promising candidate in temperature sensing application.
Section snippets
Synthesis of the samples: Ca14Al10-x-yZn6O35:xTi4+,yMn4+
A set of nominal Ca14Al10−x%−y%Zn6O35:x%Ti4+,y%Mn4+ phosphors were manufactured via the orthodox high-temperature solid-state reaction technique (SSR). The primary analytically pure constituent oxides and carbonates reagents: CaCO3 (A.R.), Al2O3 (A.R.), ZnO (A.R.), TiO2 (A.R.), and MnCO3 (A.R.) were precisely weighed based on the stoichiometric ratio of compositions of Ca14Al10-x%Zn6O35:x%Ti4+ (x = 0, 50, 60, 70 and 80) and Ca14%Al9.3-y%Zn6O35:70%Ti4+,y%Mn4+ (y = 0.0, 0.2, 0.4, 0.6 and 0.8).
Phase identification and structure detection
The synthesized optical materials' phase identification and structure detection were confirmed by XRD, as displayed in Fig. 1(a). From the graph, it is obvious to notice that the XRD patterns of the as-prepared samples, including substrate CAZO, singly doped CAZO:5%Ti4+, CAZO:0.4%Mn4+, and CAZO:15%Mn4+ were all coincident with the standard PDF card JCPDS NO. 50–0426 without any impurity phases nor distinct diffraction peaks' shift, signifying that the doping of a small number of dual TM ions
Conclusion
For the sake of meeting the needs of synthesizing economically rational optical materials with the excellent temperature detection ability, and circumventing the intrinsic limitations resulted from the conventional thermally coupled level strategy-based single-composition temperature sensing materials, we have investigated the novel rare-earth free activated phosphor with dual luminescent centers. Benefiting from the strong thermal stability of TM Mn4+ ion and the excellent thermal quenching
Credit author statement
Yu Ding, Methodology, Validation, Formal analysis, Investigation, Data curation, Writing - original draft, Ning Guo, Conceptualization, Methodology, Validation, Formal analysis, Investigation, Resources, Supervision, Project administration, Funding acquisition, Miaomiao Zhu, Methodology, Validation, Wenzhen Lv, Methodology, Validation, Ruizhuo Ouyang, Validation, Resources, Supervision, Project administration, Funding acquisition, Baiqi Shao, Validation, Resources.
Declaration of competing interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgment
This work is financially supported by the National Natural Science Foundation of China (Grant No. 21401130); the Opening Research Fund of the State Key Laboratory of Rare-Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences (RERU2014005); and Shanghai Young College Teachers Training Project (slg15057).
References (49)
- et al.
On the analysis of the thermal line shift and thermal line width of ions in solids
J. Lumin.
(2015) - et al.
Optical temperature sensing using a new thermographic phosphor
Sens. Actuators A Phys.
(2015) - et al.
A ratiometric optical thermometer with high sensitivity and superior signal discriminability based on Na3Sc2P3O12: Eu2+, Mn2+ thermochromic phosphor
Chem. Eng. J.
(2019) - et al.
Investigation of luminescence from LuAG: Mn 4+ for physiological temperature sensing
Opt. Mater.
(2017) - et al.
Quantum dot-containing polymer particles with thermosensitive fluorescence
Biosens. Bioelectron.
(2013) - et al.
Multichannel luminescence properties and ultrahigh-sensitive optical temperature sensing of mixed-valent Eu2+/Eu3+ co-activated Ca8ZrMg(PO4)6(SiO4) phosphors
J. Alloys Compd.
(2019) - et al.
Enhance the luminescence properties of Ca14Al10Zn6O35:Ti4+ phosphor via cation vacancies engineering of Ca2+ and Zn2+
Ceram. Int.
(2019) - et al.
A spatial/temporal dual-mode optical thermometry platform based on synergetic luminescence of Ti4+-Eu3+ embedded flexible 3D micro-rod arrays: high-sensitive temperature sensing and multi-dimensional high-level secure anti-counterfeiting
Chem. Eng. J.
(2019) - et al.
A deep red phosphor Li2MgTiO4:Mn4+ exhibiting abnormal emission: potential application as color converter for warm w-LEDs
Chem. Eng. J.
(2016) - et al.
Charge transfer-type fluorescence of Ti-doped Ca 14 Al 10 Zn 6 O 35
J. Lumin.
(2017)
Red-emitting phosphor Rb 2 TiF 6 :Mn 4+ with high thermal-quenching resistance for wide color-gamut white light-emitting diodes
Opt. Mater.
New strategy for designing orangish-red-emitting phosphor via oxygen-vacancy-induced electronic localization
Light Sci. Appl.
808 nm light triggered up-conversion optical nano-thermometer YPO4:Nd3+/Yb3+/Er3+ based on FIR technology
J. Lumin.
Optical thermometric properties in Tb3+ and Eu3+-coactivated dual-emissive fluorophosphate phosphors
Optic Laser. Technol.
Yb 3+/Er 3+ co-doped CaMoO 4 : a promising green upconversion phosphor for optical temperature sensing
J. Alloys Compd.
Sn2+/Mn2+ codoped strontium phosphate (Sr2P2O7) phosphor for high temperature optical thermometry
J. Alloys Compd.
Instantaneous ballistic velocity of suspended Brownian nanocrystals measured by upconversion nanothermometry
Nat. Nanotechnol.
Luminescence nanothermometry
Nanoscale
Improved luminescence and energy-transfer properties of Ca14Al10Zn6O35:Ti(4+),Mn(4+) deep-red-emitting phosphors with high brightness for light-emitting diode (LED) plant-growth lighting
Dalton Trans.
A novel optical thermometry strategy based on diverse thermal response from two intervalence charge transfer states
Adv. Funct. Mater.
Remarkable NIR enhancement of multifunctional nanoprobes for in vivo trimodal bioimaging and upconversion optical/T2 -weighted MRI-guided small tumor diagnosis
Adv. Funct. Mater.
None-rare-earth activated Ca14Al10Zn6O35:Bi3+,Mn4+ phosphor involving dual luminescent centers for temperature sensing
J. Am. Ceram. Soc.
Unveiling in vivo subcutaneous thermal dynamics by infrared luminescent nanothermometers
Nano Lett.
Doped oxides for high-temperature luminescence and lifetime thermometry
Annu. Rev. Mater. Res.
Cited by (11)
Enhancement of up-conversion luminescence efficiency and temperature sensing properties in BaWO<inf>4</inf>: Ho<sup>3+</sup>/Yb<sup>3+</sup> phosphor via Gd<sup>3+</sup> incorporation
2022, Materials Today CommunicationsCitation Excerpt :The measurement of temperature is of great significance in various fields such as industrial, biological, scientific research, and our daily life [1].
Luminescence thermometry with transition metal ions. A review
2022, Coordination Chemistry ReviewsInsights into the crystal structure and photophysical response of Dy<sup>3+</sup> doped Li<inf>3</inf>Y<inf>3</inf>Te<inf>2</inf>O<inf>12</inf> for ratiometric temperature sensing
2022, Journal of Science: Advanced Materials and DevicesCitation Excerpt :Optical temperature sensing is based on the temperature-dependent luminescence properties of the phosphors, and such phosphors are termed thermographic phosphors. Generally, temperature-dependent photoluminescence parameters such as FIR-fluorescence intensity ratio, emission color, spectral shift, and luminescence decay time are selected [10–13]. The FIR method offers superior qualities like self-referencing and negligible drift through which better sensitivity and accuracy can be achieved [14,15].
Photoluminescence and optical temperature measurement of Mn<sup>4+</sup>/Er<sup>3+</sup> co-activated double perovskite phosphor through site-advantageous occupation
2021, Spectrochimica Acta - Part A: Molecular and Biomolecular SpectroscopyCitation Excerpt :It is becoming a very active but challenging research topic and direction. Luminescent materials have certain optical properties, such as emission peak position, the emission spectrum shape, the fluorescence intensity ratio, spectral linewidth, fluorescence intensity, polarization anisotropy, and fluorescence decay lifetime, these characteristics will change with temperature [9–16]. The methods of temperature measurement include fluorescence intensity ratio (FIR) temperature measurement, fluorescence lifetime temperature measurement, rising edge temperature measurement, etc. [15].