Pr < 3 + >-doped SrY2O4 luminescent material as well as preparation method and application thereof in temperature measurement

Abstract

The invention relates to the technical field of luminescent material synthesis and temperature measurement, and discloses a Pr < 3 + >-doped SrY2O4 luminescent material, a preparation method thereof and an application of the Pr < 3 + >-doped SrY2O4 luminescent material in temperature measurement. The expression of the luminescent material is SrY2O4: xPr < 3 + >, and x is more than 0 and less than or equal to 4%. The luminescent material provided by the invention adopts an inorganic material as a matrix fluorescent material, expensive rare elements do not need to be introduced, specifically, yttrium oxide, strontium carbonate and praseodymium oxide are selected as raw materials, and by controlling the doping concentration of praseodymium oxide, the obtained SrY2O4: xPr < 3 + > luminescent material shows relatively high sensitivity in a fluorescence variable-temperature experiment.

Description

Technical Field

[0001] The present invention relates to the technical field of luminescent material synthesis and temperature measurement, and in particular to a Pr 3+ Doped SrY2O4 luminescent material, preparation method thereof and application in temperature measurement. Background Art

[0002] Luminescent materials are functional materials with a wide range of types and uses, such as up-conversion luminescent materials, fluorescent materials, etc. Among them, fluorescent materials, especially rare earth-doped fluorescent materials, have been widely used in searchlighting, display, field emission and other fields, and continue to integrate with other high-tech technologies to continuously expand into other fields.

[0003] Strontium yttrium (SrY2O4) is a rare earth material belonging to the orthorhombic system, which is composed of a secondary octahedral framework (R2O4)2 (R is a rare earth metal) containing rare earth ions, and rare earth ions exist inside. It has good physical and chemical stability, unique properties in luminescence and magnetic properties, and good chemical strength and thermal strength.

[0004] The performance of phosphors is usually determined by the matrix material and the rare earth ions doped. 3+ With two electrons filling the 4f orbital, the electronic configuration is [Xe]4f 2 , and Pr 3+ Ionic 1 The S0 energy level has a high energy level and is prone to produce emission spectra with different peak characteristics under ultraviolet or extreme ultraviolet light excitation. 3+ As lanthanide ions, ions have a large number of radiation transitions and a wide range of luminescence wavelengths, including blue, green, red, and orange, and have great development potential. 2+ 、Ce 3+ The excitation and emission spectra of other lanthanide ions and other transition metal ions are different. 3+ The different electronic configurations of ions produce different types of electronic transitions, mainly presenting a series of spike excitations and emissions.

[0005] At the same time, Pr 3+ The deep red and near-infrared light emitted by ions have low optical scattering and absorption in biological tissues and have a certain ability to penetrate biological tissues; their luminescent imaging can effectively avoid the occurrence of biological autofluorescence and has a higher signal-to-noise ratio than traditional fluorescent materials. 3+ Ionic rare earth materials are expected to achieve breakthroughs in emerging fields such as optical storage, stress sensing, and bioimaging, and have enormous application prospects and social benefits.

[0006] In addition, rare earth-doped inorganic phosphors still have basic problems such as weak luminous intensity, low efficiency and low relative sensitivity in the fields of luminescence, display and optical temperature measurement. At the same time, due to the light scattering phenomenon on the surface of the metal powder itself, Pr 3+ There are great differences in the appearance color and luminous efficacy of the finished products prepared by ions. 11 ), due to its high relative molecular mass, the dosage and weighing accuracy of the drug also have a very important impact on the appearance color, efficacy and transparency of the finished product.

[0007] At present, rare earth-doped inorganic phosphors, namely fluorescent materials, are gradually developing towards high efficiency and energy saving, and their application areas are constantly expanding and breaking through, spreading from traditional lighting and display fields to emerging fields such as field emission, information storage and reading, medical care, infrared detection, medical bio-imaging, and food testing. Compared with traditional materials, fluorescent materials based on rare earth ion doping have more excellent functions. For example, optical fiber fluorescence temperature sensors that measure temperature based on the characteristics that the ratio of fluorescence intensity of different spectral bands of rare earth ions changes with temperature have advantages that traditional temperature sensors do not have. Therefore, many scholars are currently trying to use different rare earth elements to dope luminescent materials to update past products.

[0008] Zhou Liya disclosed in "Preparation and Performance Research of Red Phosphor for White Light LED Lamps" that AGd(MoO4)2:Eu was synthesized by high temperature solid phase method. 3+ (A=Li, Na, K) red phosphor, it was found that the sample can effectively absorb ultraviolet light and transfer energy to Eu 3+ , so that it emits characteristic red light with a wavelength of 615nm after absorbing energy, which can be used in white LED lights; for example, Tian Xiuying [9] used H3BO3 flux-assisted solid phase method to prepare CaTiO3:Pr 3+ Red phosphor, its relative sensitivity is as high as 6837 / T 2 K -1 After three cycles of heating and cooling, the color difference at the same temperature still does not change much. The prepared samples have high sensitivity, good thermal stability, reversibility and repeatability, and are expected to be applied in the field of new optical temperature measurement.

[0009] In "A tellurite near-infrared fluorescent material, its preparation method and application", Zhong Jiyou disclosed the preparation and synthesis of a material that can be effectively excited by 460nm blue light, emitting a continuously variable near-infrared spectrum with a peak wavelength of 820-850nm. It has a high luminous efficiency (more than 30%) and can meet the development needs of near-infrared light-emitting diodes based on fluorescence conversion. Summary of the invention

[0010] The purpose of the present invention is to provide a Pr 3+ Doped SrY2O4 luminescent material, preparation method thereof and application in temperature measurement.

[0011] In order to achieve the above object, the first aspect of the present invention provides a Pr 3+ Doped SrY2O4 luminescent material, the luminescent material is expressed as SrY2O4:xPr 3+ , where 0<x≤4%.

[0012] Preferably, 0.1%≤x≤0.7%.

[0013] The second aspect of the present invention provides a Pr as described in the first aspect of the present invention. 3+ A method for preparing a doped SrY2O4 luminescent material, the method comprising:

[0014] The Y source, Sr source, and Pr source were subjected to a first grinding treatment, and then transferred to a ceramic crucible, and the ceramic crucible was placed in a muffle furnace for sintering treatment. The sintering temperature was increased from room temperature to 323K, and then increased to 1073K after 100min, and then slowly increased to 1673K after 200min, and finally kept at 1673K for 120min, and then slowly cooled to room temperature with the furnace, taken out, and then subjected to a second grinding treatment.

[0015] Further preferably, the molar concentration ratio of the Y source, the Sr source, and the Pr source is 1:1:0.1-4.

[0016] Preferably, the Y source is Y2O3.

[0017] Preferably, the Sr source is SrCO3.

[0018] Further preferably, the Pr source is Pr6O 11 .

[0019] Preferably, the conditions of the first grinding process and the second grinding process at least meet: the time is 30 minutes.

[0020] Further preferably, before the first grinding process is performed, a flux is added, and the flux is NaBF4 or KF·H2O.

[0021] Preferably, the concentration of the flux is 0.1-5wt%.

[0022] The third aspect of the present invention provides the use of the luminescent material described in the first aspect of the present invention in temperature measurement.

[0023] The luminescent material and method provided by the present invention also have at least the following beneficial effects:

[0024] (1) The method provided by the present invention uses inorganic materials as the base fluorescent material, does not need to introduce expensive rare elements, and the traditional preparation temperature is often higher than 1273K (if the present invention adopts the traditional preparation method, the preparation temperature needs to reach 1673K). Therefore, the method provided by the present invention has mild conditions and is expected to be mass-produced in factories.

[0025] (2) The present invention uses yttrium oxide, strontium carbonate and praseodymium oxide as raw materials, and controls the doping concentration of praseodymium oxide to obtain SrY2O4:xPr 3+ The luminescent material showed high sensitivity in the fluorescence temperature change experiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is an XRD analysis diagram of the luminescent materials obtained in Example 1, Example 2, Example 4, Example 7 and Comparative Example 1 of the present invention;

[0027] Figure 2 It is the ultraviolet-visible diffuse reflection spectrum analysis diagram of the luminescent materials obtained in Example 1 of the present invention and Comparative Example 1;

[0028] Figure 3 is the luminescent material obtained in Example 1 [F (R ∞ )hv] 2 For hv relationship diagram;

[0029] Figure 4 is the luminescent material obtained in Example 1 of the present invention [F (R ∞ )hv] 2 For hv relationship diagram;

[0030] Figure 5 is the SEM image of the luminescent material obtained in Example 1 of the present invention at different magnifications;

[0031] Figure 6 1 is an EDS spectrum analysis diagram of the luminescent material obtained in Example 1 of the present invention at different magnifications;

[0032] Figure 7 is a distribution diagram of elements in the luminescent material obtained in Example 1 of the present invention;

[0033] Figure 8 It is a fluorescence spectrum analysis diagram of the luminescent materials obtained in Examples 1 to 11 of the present invention and Comparative Example 1 under the excitation of 273nm ultraviolet light;

[0034] Fig. 9 It is a fluorescence spectrum analysis diagram of the luminescent materials obtained in Examples 1 to 11 of the present invention and Comparative Example 1 under the excitation of 491nm ultraviolet light;

[0035] Fig.10 It is an emission spectrum analysis diagram of the luminescent materials obtained in Example 1, Example 12 to Example 15 of the present invention under the excitation of ultraviolet light at 273nm;

[0036] Fig.11 It is an emission spectrum analysis diagram of the luminescent materials obtained in Example 1, Example 12 to Example 15 of the present invention under the excitation of 491nm ultraviolet light;

[0037] Fig.12 It is an analysis chart of emission spectra of the luminescent materials obtained in Example 1 and Example 16 of the present invention under the excitation of ultraviolet light at 273nm;

[0038] Fig.13 It is an analysis diagram of the excitation spectrum of the luminescent materials obtained in Example 1 and Example 16 of the present invention under the excitation of 491nm ultraviolet light;

[0039] Fig.14 This is a diagram of a fluorescence temperature variation experiment conducted on the luminescent material obtained in Example 1 of the present invention. DETAILED DESCRIPTION

[0040] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0041] The present invention will be described in detail below by way of examples. In the following examples, unless otherwise specified, the raw materials are all commercially available.

[0042] Example 1: SrY2O4:0.5%Pr 3+ Luminescent Materials

[0043] This example is used to provide a method for preparing a luminescent material, the method comprising:

[0044] Weigh Y2O3, SrCO3, Pr6O according to the molar concentration ratio of 1:1:0.5 11 , among which Pr6O 11 The concentration of Y2O3, SrCO3, Pr6O 11The material is placed in an agate mortar for the first grinding treatment, manually ground for 30 minutes to make it fully mixed, then transferred to a ceramic crucible, and the ceramic crucible is placed in a muffle furnace for sintering treatment. The sintering temperature is increased from room temperature to 323K, then increased to 1073K after 100 minutes, and then slowly increased to 1673K after 200 minutes. Finally, it is kept at 1673K for 120 minutes, and then slowly cooled to room temperature with the furnace, taken out, and placed in the agate mortar for the second grinding treatment, manually ground for 30 minutes to make it fully mixed, to obtain a luminescent material.

[0045] Example 2: SrY2O4:0.1%Pr 3+ Luminescent Materials

[0046] The method in Example 1 was followed, except that Y2O3, SrCO3, Pr6O3 were weighed in a molar concentration ratio of 1:1:0.1. 11 The remaining steps and parameters are the same as in Example 1.

[0047] Example 3: SrY2O4:0.2%Pr 3+ Luminescent Materials

[0048] The method in Example 1 was followed, except that Y2O3, SrCO3, Pr6O3 were weighed in a molar concentration ratio of 1:1:0.2. 11 The remaining steps and parameters are the same as in Example 1.

[0049] Example 4: SrY2O4:0.3%Pr 3+ Luminescent Materials

[0050] The method in Example 1 was followed, except that Y2O3, SrCO3, Pr6O3 were weighed in a molar concentration ratio of 1:1:0.3. 11 The remaining steps and parameters are the same as in Example 1.

[0051] Example 5: SrY2O4:0.4%Pr 3+ Luminescent Materials

[0052] The method in Example 1 was followed, except that Y2O3, SrCO3, Pr6O3 were weighed in a molar concentration ratio of 1:1:0.4. 11 The remaining steps and parameters are the same as in Example 1.

[0053] Example 6: SrY2O4:0.6%Pr 3+ Luminescent Materials

[0054] The method in Example 1 was followed, except that Y2O3, SrCO3, and Pr6O were weighed in a molar concentration ratio of 1:1:0.6.11 The remaining steps and parameters are the same as in Example 1.

[0055] Example 7: SrY2O4: 0.7% Pr 3+ Luminescent Materials

[0056] The method in Example 1 was followed, except that Y2O3, SrCO3, Pr6O3 were weighed in a molar concentration ratio of 1:1:0.7. 11 The remaining steps and parameters are the same as in Example 1.

[0057] Example 8: SrY2O4:1%Pr 3+ Luminescent Materials

[0058] The method in Example 1 was followed, except that Y2O3, SrCO3, Pr6O3 were weighed in a molar concentration ratio of 1:1:1. 11 The remaining steps and parameters are the same as in Example 1.

[0059] Example 9: SrY2O4:2%Pr 3+ Luminescent Materials

[0060] The method in Example 1 was followed, except that Y2O3, SrCO3, Pr6O3 were weighed in a molar concentration ratio of 1:1:2. 11 The remaining steps and parameters are the same as in Example 1.

[0061] Example 10: SrY2O4:3%Pr 3+ Luminescent Materials

[0062] The method in Example 1 was followed, except that Y2O3, SrCO3, Pr6O3 were weighed in a molar concentration ratio of 1:1:3. 11 The remaining steps and parameters are the same as in Example 1.

[0063] Example 11: SrY2O4:4%Pr 3+ Luminescent Materials

[0064] The method in Example 1 was followed, except that Y2O3, SrCO3, Pr6O3 were weighed in a molar concentration ratio of 1:1:4. 11 The remaining steps and parameters are the same as in Example 1.

[0065] Example 12

[0066] The method in Example 1 was followed, except that KF·H2O with a concentration of 0.1 wt% was added before the first grinding treatment. The remaining steps and parameters were the same as in Example 1.

[0067] Embodiment 13

[0068] The method in Example 1 was followed, except that KF·H2O with a concentration of 1 wt% was added before the first grinding treatment. The remaining steps and parameters were the same as in Example 1.

[0069] Embodiment 14

[0070] The method in Example 1 was followed, except that KF·H2O with a concentration of 3 wt% was added before the first grinding treatment. The remaining steps and parameters were the same as in Example 1.

[0071] Embodiment 15

[0072] The method in Example 1 was followed, except that KF·H2O with a concentration of 5 wt% was added before the first grinding treatment. The remaining steps and parameters were the same as in Example 1.

[0073] Example 16

[0074] The method in Example 1 was followed, except that NaBF4 with a concentration of 2 wt% was added before the first grinding treatment. The remaining steps and parameters were the same as in Example 1.

[0075] Comparative Example 1: SrY2O4 material

[0076] The method in Example 1 was followed, except that Pr6O was not added. 11 The remaining steps and parameters are the same as in Example 1.

[0077] Test Example 1

[0078] The products obtained in the above examples and comparative examples were subjected to XRD analysis.

[0079] For example, Figure 1 The XRD analysis diagrams of the luminescent materials obtained in Example 1, Example 2, Example 4, Example 7 and Comparative Example 1 are shown in FIG. Figure 1 It can be seen that undoped Pr 3+ The diffraction peak shape of SrY2O4 material is different from that of Pr doped with different concentrations. 3+ The SrY2O4 diffraction peak shape is consistent with that of the standard card PDF#32-1272, which shows that the prepared sample has good crystallinity, the obtained phase is relatively single, the sample crystal form is very good, and Pr 3+ The doping does not change the crystal structure of SrY2O4.

[0080] Moreover, the strongest diffraction peaks of the luminescent materials obtained in Example 1, Example 2, Example 4, Example 7 and Comparative Example 1 are all located near 2θ=30.5°, corresponding to the (320) crystal plane. There are two secondary peaks next to the strongest diffraction peak, located at 2θ=30° and 2θ=31.5°, corresponding to the (040) crystal plane and the (121) crystal plane, respectively. At the same time, a careful comparison with the standard card PDF#32-1272 revealed that the diffraction peaks were slightly shifted toward the large angle direction, which may be due to the Y 3+ The radius is smaller than Pr 3+ Radius, Y in matrix element 3+ The cation sites in the Pr 3+ As the doping concentration increases, the resulting luminescent material has a certain degree of lattice distortion.

[0081] Test Example 2

[0082] The products obtained in the above examples and comparative examples were subjected to UV-visible diffuse reflectance spectroscopy analysis.

[0083] For example, Figure 2 The UV-visible diffuse reflectance spectra of the luminescent materials obtained in Example 1 and Comparative Example 1 are shown in FIG. Figure 3 The luminescent material obtained in Comparative Example 1 has [F(R ∞ )hv] 2 For the hv relationship diagram, Figure 4 is the luminescent material obtained in Example 1 [F (R ∞ )hv] 2 Relationship diagram of hv.

[0084] Depend on Figure 2 It can be seen that the obtained luminescent material has a high reflectivity platform between 400nm-800nm, and begins to drop sharply between 200nm-400nm. This may be because Pr 3+ The reason for the transition between 4f-5d.

[0085] Depend on Figure 3 and Figure 4 , and the following formula shows that the optical bandgap value E of the luminescent materials obtained in Example 1 and Comparative Example 1 is g The difference is not big, however, the optical bandgap value is often related to the crystallinity, grain and particle size, morphology and other aspects of the obtained luminescent material, so this may be the result of the combined effect of many aspects;

[0086] Among them, R ∞ is the reflectivity ratio of the sample to the ideal sample BaSO4; F(R ∞ ) is the KM function; hv is the photon energy; E g is the optical bandgap value.

[0087] Test Example 3

[0088] The products obtained in the above examples and comparative examples were subjected to SEM analysis.

[0089] For example, Figure 5 The SEM images of the luminescent material obtained in Example 1 at different magnifications are shown in the figure. As can be seen from the figure, the luminescent material obtained presents an irregular spherical structure, and the irregular spherical structure has a certain degree of aggregation. At the same time, since the luminescent material is calcined at high temperature, its particle size is large and there is a certain agglomeration phenomenon. This may be due to the use of high-temperature solid-phase synthesis. Due to the influence of surface energy, during the synthesis process, the grain boundaries of large grains diffuse toward the grain boundaries of small grains, thereby causing the grains to continue to grow larger.

[0090] Test Example 4

[0091] The products obtained in the above examples and comparative examples were subjected to EDS energy spectrum analysis.

[0092] For example, Figure 6 The EDS spectrum analysis diagram of the luminescent material obtained in Example 1 at different magnifications is shown below. Figure 7 This is the element distribution diagram of the luminescent material obtained in Example 1.

[0093] Depend on Figure 6 It can be seen that in the luminescent material obtained in Example 1, the elements are irregularly distributed in the entire observation area, and Y, Sr, and O elements mainly account for the majority. Although the doping amount of Pr3+ is low, it is still evenly distributed.

[0094] Depend on Figure 7 It can be seen that the luminescent material obtained in Example 1 mainly contains Y, Sr, O, and Au elements, and contains the impurity element Au, wherein Au comes from the gold spraying layer.

[0095] Test Example 5

[0096] The products obtained in the above examples and comparative examples were subjected to fluorescence spectrum analysis.

[0097] For example, Figure 8 The fluorescence spectrum analysis diagram of the luminescent materials obtained in Examples 1 to 11 and Comparative Example 1 under the excitation of 273nm ultraviolet light is shown in FIG. Fig. 9 This is a fluorescence spectrum analysis diagram of the luminescent materials obtained in Examples 1 to 11 and Comparative Example 1 under 491nm ultraviolet light excitation.

[0098] Depend on Figure 8It can be seen that under the excitation of 273nm ultraviolet light, the wavelength range of the obtained luminescent material is between 300nm and 800nm, which is mainly composed of a broadband peak and some narrowband peaks. Among them, the broadband peak should be due to matrix absorption, and the narrowband peak is Pr 3+ The reason for the characteristic transition of Pr is that the peak value is located at 370nm in the broadband peak of 300nm-400nm. Its emission spectrum is relatively wide, occupying the near-ultraviolet and ultraviolet regions. Between 450nm-550nm, its peak value is located at 491nm, which is Pr 3+ of 3 P0→ 3 H4 transition. At the same time, a secondary peak appears at 518nm nearby, which is Pr 3+ of 3 P1→ 3 H5 transition. After analysis, it may be Pr 3+ The doping affects the crystal field of the experimental matrix, which leads to the splitting of this part of the energy level.

[13] . Between 550nm-680nm, all are Pr 3+ The 4f-4f and 4f-5d red light emission, of which the emission peaks at 615nm and 620nm belong to 1 D2→ 3 H4, 3 P0→ 3 H6 transition. Among them, the emission intensity at 491nm is the highest. 3+ With the increase of doping amount, the fluorescence intensity shows a trend of first rising and then falling. When the doping concentration is 0.5%, the fluorescence intensity is the maximum. 3+ When the concentration increases, its fluorescence intensity gradually decreases. However, the stronger the fluorescence intensity, the higher the peak value, the more electrons leaving the conduction band and holes and the more photon energy generated, and the higher the recombination rate of electrons and holes. This is because the fluorescence intensity of fluorescent materials is affected by many factors, among which it is closely related to the amount of doping elements and the distance between the atoms migrating during the energy migration process. 3+ In the process of excited transition, as the concentration of doping ions increases, Pr 3+ There is an interaction between them, and with the continuous increase of doping ion concentration, Pr 3+ As the distance between them decreases, the degree of interaction increases, and the energy migration between ions becomes more frequent. When the energy is transferred to the quenching impurities and quenching centers, Pr 3+ Quenching begins, which is why doping Pr 3+ With the increase of concentration, the fluorescence intensity decreased.

[0099] Depend on Fig. 9It can be seen that at a detection wavelength of 491nm, the wavelength range of the obtained luminescent material is between 200nm and 550nm, among which there is a relatively wide excitation band mainly in the short-wave UV region of 250nm-300nm, with a peak at 274nm, corresponding to 3 H4→4f 2 5d 1 The absorption transition of shows that the sample has a strong absorption ability for ultraviolet light.

[0100] Test Example 6

[0101] The products obtained in the above examples and comparative examples were subjected to emission spectrum analysis.

[0102] For example, Fig.10 This is an emission spectrum analysis diagram of the luminescent materials obtained in Example 1, Example 12 to Example 15 under 273nm ultraviolet light excitation, Fig.11 This is an emission spectrum analysis diagram of the luminescent materials obtained in Example 1 and Example 12 to Example 15 under the excitation of 491nm ultraviolet light.

[0103] Depend on Fig.10 It can be seen that under the excitation of 273nm ultraviolet light, the wavelength range of the obtained luminescent material is between 300nm and 800nm, which is basically the same as the emission spectrum of the luminescent material obtained in Example 1 (without adding KF) in terms of broadband peak position and narrowband peak position. Among them, the broadband peak may be mainly related to the matrix absorption, while the narrowband peak is mainly due to the absorption of Pr 3+ feature 3 P0→ 3 H4, 3 P1→ 3 H5 transition.

[0104] Depend on Fig.11 As shown, at a detection wavelength of 491 nm, the wavelength range of the obtained luminescent material is between 200 nm and 472 nm, which is substantially the same as the broadband peak position of the luminescent material obtained in Example 1 (without KF addition).

[0105] Moreover, at low concentrations, when 0.1% and 1% KF·H2O were added, the fluorescence intensity decreased. This may be because at low concentrations, F - The radius is smaller than O 2- , occupying the anion site, generating other transition energy levels, for Pr 3+ At high concentrations, when 3% and 5% KF were added, the fluorescence intensity increased and the splitting phenomenon was obvious. This may be due to the effect of KF·H2O on the transition energy level of the sample SrY2O4:0.5%Pr 3+ The crystal field of Pr 3+The energy transfer between them causes the fluorescence intensity to increase instead of decrease.

[0106] Test Example 7

[0107] The products obtained in the above-mentioned Example 1 and Example 16 were subjected to emission spectrum and excitation spectrum analysis. Fig.12 The emission spectrum analysis diagram of the luminescent materials obtained in Example 1 and Example 16 under the excitation of 273nm ultraviolet light, Fig.13 This is an analysis diagram of the excitation spectra of the luminescent materials obtained in Example 1 and Example 16 under 491nm ultraviolet light excitation.

[0108] Depend on Fig.12 As shown, the emission spectrum of the luminescent material obtained in Example 16 has decreased in the broadband peak at 300nm-400nm and the peak value of the strongest diffraction peak at 491nm.

[0109] Depend on Fig.13 As shown, the excitation spectrum of the luminescent material obtained in Example 16 decreases at a detection wavelength of 491 nm, and the peak value of the diffraction peak located at 273 nm decreases.

[0110] As can be seen from the above, when adding 2wt% NaBF4, the fluorescence intensity decreases. This may be due to the fact that at this concentration, 2wt% NaBF4 has a 3+ The transition energy level of the ions is affected, resulting in a decrease in the fluorescence intensity.

[0111] Application Example 1

[0112] This example is used to provide a fluorescence temperature change experiment for the luminescent material obtained in Example 1 of the present invention. This experiment takes room temperature 298K as the base, sets a temperature curve, and measures the fluorescence intensity every 25K until the temperature rises to 573K. Other experimental parameters are shown in Table 1. Fig.14 This is a graph showing the results of the variable temperature experiment.

[0113] Table 1

[0114] category Comparative Example 1 Excitation wavelength 274nm Scan range 300nm-800nm Scan speed 1200nm / min Emission / excitation wavelength slit 5.0nm Voltage 500v

[0115] Depend on Fig.14 It can be seen that the fluorescence intensity of the obtained luminescent material is the largest at 373K, and the overall fluorescence intensity reaches the highest at 373K. Then, as the temperature increases, the fluorescence intensity gradually decreases, which is caused by the temperature quenching effect.

[0116] Depend on Fig.14 It can be seen that in the broadband peak of 300nm-400nm, its peak value gradually decreases with the increase of temperature, which may be because the matrix undergoes thermal quenching as the temperature continues to rise.

[0117] Between 450nm-550nm, its peak is at 491nm, which is Pr 3+ of 3 P0→ 3 H4 transition, the second strongest peak is at 518nm, which is Pr 3+ of 3 P1→ 3 H5 transition. Between 298K-373K, as the temperature increases, the fluorescence intensity also increases. When the temperature rises to between 373K-573K, as the temperature increases, the fluorescence intensity decreases. After analysis, the increase in fluorescence intensity between 298K-373K may be because the lattice phonons provide a certain amount of energy at high temperatures, thereby making up for part of the energy imbalance between the receptor and the ligand. When the temperature rises to between 373K-573K, the vibration of the matrix lattice continues to increase, which in turn leads to an increase in the interaction between electrons and phonons and an increase in the rate of non-radiative transitions, resulting in a decrease in luminescence intensity and lifetime, that is, thermal quenching occurs. Generally speaking, the fluorescence intensity of luminescent materials is greatly affected by temperature. Most luminescent materials have thermal quenching, and it will gradually decrease with increasing temperature.

[0118] Depend on Fig.14 (b) and (e) show that the experimental data are tested by the temperature measurement formula and it is found that the experimental data conform to the temperature measurement equation and can be used for temperature measurement. It conforms to the Expdecl equation in the range of 298K-373K, as shown in As shown. In the range of 373K-573K, it conforms to the Boltzmann temperature measurement equation, as shown.

[0119] Depend on Fig.14 (b) It can be seen that by substituting the corresponding data for calculation, it can be seen that in the range of 298K-373K, the fitting degree R=0.99125, and the adjusted R 2 =0.97375, the experimental data has a high degree of conformity and is consistent with the Expdecl equation. Fig.14 (c)-(d) show that its absolute sensitivity (S a ) and relative sensitivity (S r ) is calculated as (T is Kelvin temperature, A1 = 1257414.52655, y0 = 0.08487, t1 = 16.86149, adjusted R 2 =0.97375, R 2 =0.99125), the calculated results are 0.00693K -1 and 1.413% K -1 @298K, it can be seen that its sensitivity is high and can be used for temperature measurement.

[0120] Depend on Fig.14 (e) It can be seen that by substituting the corresponding data for calculation, it can be seen that within the range of 373K-573K, the fitting degree R 2 =0.99082, adjusted R 2 =0.98951, the experimental data is highly consistent with the Boltzmann temperature measurement equation. Fig.14 (f)-(g) show that its absolute sensitivity (S a ) and relative sensitivity (S r ) is calculated as (Where T is Kelvin temperature, A2=6.04854, B=1652.76604), the calculated results are 0.0017K respectively -1 and 1.188% K -1 @373K, it can be seen that its sensitivity is high and can be used for temperature measurement.

[0121] According to the conformity of the temperature measurement equation in the temperature range of 298K-573K, it is analyzed that the SrY2O4:0.5%Pr obtained in Example 1 3+ Can be used for temperature measurement.

[0122] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A Pr 3+ The doped SrY2O4 luminescent material is characterized in that: The expression of the luminescent material is SrY2O4:xPr 3+ , where 0<x≤4%.

2. Pr according to claim 1 3+ Doped SrY2O4 luminescent material, wherein 0.1％≤x≤0.7％。 3. A Pr as claimed in claim 1 or 2 3+ The method for preparing a doped SrY2O4 luminescent material is characterized in that: The method includes: The Y source, Sr source, and Pr source were subjected to a first grinding treatment, and then transferred to a ceramic crucible, and the ceramic crucible was placed in a muffle furnace for sintering treatment. The sintering temperature was increased from room temperature to 323K, and then increased to 1073K after 100min, and then slowly increased to 1673K after 200min, and finally kept at 1673K for 120min, and then slowly cooled to room temperature with the furnace, taken out, and then subjected to a second grinding treatment.

4. The preparation method according to claim 3, wherein The molar concentration ratio of the Y source, the Sr source and the Pr source is 1:1:0.1-4.

5. The preparation method according to claim 3 or 4, wherein The Y source is Y2O3; And / or, the Sr source is SrCO3; And / or, the Pr source is Pr6O 11 .

6. The preparation method according to claim 3 or 4, wherein: The conditions of the first grinding process and the second grinding process at least meet: the time is 30 minutes.

7. The preparation method according to claim 3 or 4, wherein: Before the first grinding process is performed, a flux is added, and the flux is NaBF4 or KF·H2O.

8. The preparation method according to claim 7, wherein: The concentration of the flux is 0.1-5wt%.

9. Pr prepared by the method according to any one of claims 3 to 8 3+ Doped SrY2O4 luminescent material.

10. Use of the luminescent material according to claim 9 in temperature measurement.

Images