A rare earth Dy 3+ Temperature detection method based on ion excitation intensity ratio

Abstract

The invention belongs to the technical field of temperature detection and discloses a method based on rare earth Dy 3+ The temperature detection method of ion excitation intensity ratio. Including measuring Dy at a certain temperature 3+ The peak intensity of the excitation light corresponding to the two emission wavelengths A and B of the doped CaWO4 phosphor, the ratio of the excitation light intensity #imgabs0# and #imgabs1# at the above temperature, and the change of Dy 3+ Repeat the above steps to fit the curve obtained in step S3 using the formula #imgabs2#, and use the rare earth Dy 3+ The excitation peak intensity corresponding to the two different emission wavelengths of the ion is quantitatively related to the intensity ratio of the two and the temperature to achieve a rare earth Dy 3+ A new method for temperature measurement based on the ion excitation intensity ratio technology, based on rare earth Dy 3+ The ion excitation intensity ratio temperature measurement technology has good cycle stability, repeatability and high temperature detection sensitivity.

Description

Technical Field

[0001] The invention belongs to the technical field of temperature detection and particularly relates to a method for detecting a temperature of a room temperature based on rare earth Dy 3+ Temperature detection method based on ion excitation intensity ratio. Background Art

[0002] Temperature is a very important parameter in the fields of chemical reactions, biological functions and various physical phenomena. Local temperature measurement on a smaller scale often relies on non-contact temperature measurement technology, the most common of which is infrared thermal imaging temperature measurement, which measures the temperature of the surface of an object based on the thermal radiation emitted by the object. Another non-contact temperature measurement technology that has received widespread attention is fluorescence temperature detection technology, which measures temperature by detecting various fluorescence spectroscopic parameters of fluorescent materials that vary with temperature. Compared with traditional thermal imaging temperature measurement, fluorescence temperature detection technology can measure lower temperatures and non-invasively detect temperature under the surface of an object, and has the advantages of strong anti-interference ability, high sensitivity and spatial resolution, and rapid response.

[0003] In fluorescence temperature detection technology, the most widely used fluorescent materials are microcrystalline or nanocrystalline fluorescent materials doped with trivalent lanthanide ions. Trivalent lanthanide ions have rich electronic energy level structures and multi-color fluorescence emission. The most widely used method in fluorescence temperature detection technology is the fluorescence intensity ratio temperature measurement method based on lanthanide ions. This method can eliminate the interference of non-temperature factors such as fluorescence loss, excitation light source power fluctuations, and the number of luminescence centers during the temperature measurement process. It has the characteristics of being less affected by external interference and strong resistance to excitation power noise. Dy in trivalent lanthanide ions 3+ The ions can emit bright blue and yellow light under ultraviolet light excitation, so they are widely used in temperature detection based on fluorescence intensity ratio. 3+ The fluorescence intensity ratio is used to measure the temperature. 3+ Thermal coupling level 4 I 15 / 2 / 4 F 9 / 2 Ground state 6 H 15 / 2 The quantitative relationship between the intensity ratio of the two blue lights produced by the energy level transition and the temperature, such as Dy 3+ Dy-doped fluorescent materials such as Y4Al2O9, BaYF5, GdVO4, Gd2Ti2O7, Y2SiO5 and CaWO4 have all been realized. 3+ The temperature sensing behavior of two blue light intensity ratios. The other is to use Dy 3+ Temperature detection is performed by comparing the fluorescence intensity ratio of the non-thermally coupled energy levels with the temperature, for example, Dy 3+ Doped BaYF5 phosphor 4 I15 / 2 → 6 H 15 / 2 Transition blue light and 4 F 9 / 2 → 6 H 11 / 2 The quantitative relationship between the intensity ratio of the red light of the transition and the temperature, Dy 3+ Doped CaWO4 phosphor 4 G 11 / 2 → 6 H 15 / 2 Transition ultraviolet light and 4 F 9 / 2 → 6 H 15 / 2 The quantitative relationship between the intensity ratio of the blue light of the transition and the temperature, as well as the Dy 3+ Trapped luminescence of the matrix and Dy in doped Gd2Ti2O7 phosphors 3+ 4 F 9 / 2 → 6 H 15 / 2 The quantitative relationship between the intensity ratio of transition luminescence and temperature, etc.

[0004] In addition to temperature detection based on the fluorescence intensity ratio of lanthanide ions, temperature detection based on the intensity ratio technology of excited state absorption has gradually attracted people's attention. At present, the temperature detection fluorescent materials based on the excitation intensity ratio technology are mainly concentrated in the lanthanide ion Eu 3+ Doped fluorescent materials. For example, Eu 3+ The high temperature range of 611 and 580nm excitation was achieved in doped Y2O3 micro-nanocrystalline 5 D0→ 7 The quantitative relationship between the intensity ratio of F4 transition and temperature and the low temperature range of 593 and 580 nm excitation 5 D0→ 7 Quantitative relationship between the intensity ratio of F4 transition and temperature; Eu 3+ Thermally coupled energy levels are established in doped YVO4 nanophosphors 7 F2 / 7 F0 to higher order excited states 5 D2 or 5 D0 / 5 Quantitative relationship between the excitation intensity ratio of D1 transition and temperature; Eu 3+ Doped LiLaP4O 12 Nanocrystals 7 F0→ 5 D2 and 7 F2 / 7 F3 / 7 F4→ 5 Temperature sensing based on the intensity ratio of D2 transition excitation; Eu3+ The doped YVO4 phosphor also establishes the relationship between the charge transfer band intensity of the matrix VO and 7 F0→ 5 Quantitative relationship between L6 excitation intensity ratio and temperature. 3+ Doped fluorescent materials, in Er 3+ / Yb 3+ The co-doped YVO4 nano-phosphors also found 3+ ion 2 H 11 / 2 / 4 S 3 / 2 → 4 I 15 / 2 Quantitative relationship between the excitation intensity ratio of the VO charge transfer band transition and temperature.

[0005] Whether using Dy 3+ Thermal coupling level 4 I 15 / 2 / 4 F 9 / 2 To the ground state 6 H 15 / 2 The temperature is detected by the ratio of the two blue light intensities generated by the energy level transition, or Dy 3+ To detect the temperature, it is necessary to first measure the fluorescence intensity ratio of the non-thermal coupling energy level and the temperature. 3+ The emission spectrum of the ion is then calculated to obtain the required luminescence intensity value and intensity ratio. This requires the measurement of Dy 3+ The complete emission spectrum of the ion, while the measurement process of the emission spectrum is relatively long, on the other hand, the calculation of the luminescence intensity requires the solution of the integral area of ​​the emission spectrum of a specific band, which also makes the calculation of the luminescence intensity more complicated. In some cases, the integral area of ​​the luminescence intensity is difficult to accurately calculate due to the overlap of the luminescence peaks, resulting in large errors. The Dy 3+ The excitation intensity ratio temperature measurement method only needs to measure Dy 3+ The relationship between the excitation light intensity peaks corresponding to the two emission wavelengths and the temperature can be established based on the ratio of the two excitation peak intensities, without measuring Dy 3+ The complete emission or excitation spectrum of the present invention does not need to calculate the integral area, so the rare earth Dy 3+ The ion excitation intensity ratio temperature measurement technology is simple and easy to operate.

[0006] In addition, in the currently reported temperature detection methods based on the excitation intensity ratio technology, there is a strong dependence on the two excited state intensities in the excitation intensity ratio, and selecting different excited state intensities will lead to different temperature sensing characteristics. 3+ Doped LiLaP4O12 Nanocrystals 7 F0→ 5 D2 transitions are 7 F2→ 5 D2 transition, 7 F3→ 5 D2 transition or 7 F4→ 5 There are different corresponding relationships between the excitation intensity ratio of the D2 transition and the temperature, and different temperature sensing characteristics. 3+ / Yb 3+ In the co-doped YVO4 nano-phosphor, the corresponding Er 3+ ion 2 H 11 / 2 / 4 S 3 / 2 → 4 I 15 / 2 The excitation intensity ratio of the VO charge transfer band of the transition is used for temperature detection. When calculating the excitation intensity of the VO charge transfer band, if the excitation band range of the VO charge transfer band calculated by the integral is different, the quantitative relationship between the excitation intensity ratio and the temperature will also be different. Summary of the invention

[0007] In order to overcome the shortcomings of the prior art, the present invention provides a rare earth Dy 3+ The temperature detection method of ion excitation intensity ratio uses rare earth Dy 3+ The peak intensity of the excitation light corresponding to the two different emission wavelengths of the ion is quantitatively related to the excitation intensity ratio of the two and the temperature, realizing a rare earth Dy 3+ The new temperature measurement method based on ion excitation intensity ratio technology has the characteristics of simple measurement, good excitation wavelength selectivity, high temperature sensing sensitivity and good repeatability.

[0008] The above object of the present invention is achieved through the following technical solutions: a rare earth Dy 3+ The temperature detection method of ion excitation intensity ratio comprises the following specific steps:

[0009] S1.Measure Dy at a fixed temperature 3+ The peak intensity of the excitation light corresponding to the two emission wavelengths A and B of the doped CaWO4 phosphor is recorded as and Wherein i=1, 2, 3 or 4, corresponding to the excitation light of four wavelengths of λ1=352nm, λ2=326nm, λ3=366nm or λ4=388nm, respectively, the wavelength A is specifically 455nm, and the wavelength B is specifically one of 479nm, 488nm or 575nm;

[0010] S2. Calculate the excitation light intensity at the above temperature and The ratio of Where i = 1, 2, 3 or 4, corresponding to the excitation light of four wavelengths of λ1 = 352nm, λ2 = 326nm, λ3 = 366nm or λ4 = 388nm respectively;

[0011] S3. Change Dy 3+ The temperature of the CaWO4 phosphor is repeated, and the above steps S1 and S2 are repeated to obtain the excitation light intensity ratio. Relationship curve with temperature T;

[0012] S4. Using formula The curve obtained in step S3 is fitted to obtain the values ​​of fitting constants a, b, and c, and then the Dy 3+ Quantitative relationship between the excitation intensity ratio of doped CaWO4 phosphor and temperature, where R is the excitation light intensity ratio and T is the temperature.

[0013] Furthermore, the temperature in steps S1 and S2 is any temperature value within the range of 305 to 650K.

[0014] Furthermore, the temperature in step S3 is any temperature value within the range of 305 to 650 K that is different from the temperatures in steps S1 and S2.

[0015] The present invention is based on Dy 3+ In the ion excitation intensity ratio temperature measurement technology, Dy 3+ The peak intensity of the excitation light corresponding to the two emission wavelengths does not need to be measured. 3+ The complete emission or excitation spectrum is used to calculate the integrated area of ​​the emission peak or excitation peak. 3+ Ion excited state intensity ratio temperature measurement technology, the method is simple and easy to operate;

[0016] The present invention is based on Dy 3+ Ion excitation intensity ratio temperature measurement technology uses the excitation light intensity ratio (or ), where the excitation light wavelength can be Dy 3+ Any of the four strongest excitation wavelengths of ions, such as λ1 = 352nm or λ2 = 326nm or λ3 = 366nm or λ4 = 388nm, or even other stronger excitation light wavelengths. 3+ The ion excitation intensity is more selective than the excitation wavelength of the temperature measurement technique;

[0017] The present invention is based on Dy 3+The temperature measurement technology of ion excitation intensity ratio is not only applicable to Dy 3+ Doped CaWO4 phosphor, or other Dy 3+ In addition, compared with the traditional Dy-based 3+ The temperature detection method based on fluorescence intensity ratio has high temperature sensing sensitivity, good repeatability and reliability.

[0018] The beneficial effects of the present invention compared with the prior art are:

[0019] 1. The present invention uses rare earth Dy 3+ The excitation peak intensity corresponding to the two different emission wavelengths of the ion is quantitatively related to the intensity ratio of the two and the temperature to achieve a rare earth Dy 3+ A new method for temperature measurement using ion excitation intensity ratio technology;

[0020] 2. The rare earth Dy based on this invention 3+ The ion excitation intensity ratio temperature measurement technology uses the excitation intensity value as the peak intensity of the excitation peak. Compared with the excitation intensity ratio technology using the integral area of ​​the excitation peak and the traditional fluorescence intensity ratio technology, it does not require the measurement of the complete rare earth Dy 3+ Ion excitation spectroscopy or emission spectroscopy;

[0021] 3. The rare earth Dy based on this invention 3+ Ion excitation intensity ratio temperature measurement technology uses a selective excitation peak wavelength and can use rare earth Dy 3+ The ions have four best excitation wavelengths, or even other excitation wavelengths, and the temperature sensing characteristics achieved by each remain consistent;

[0022] 4. The rare earth Dy based on this invention 3+ The ion excitation intensity ratio temperature measurement technology has good cycle stability, repeatability and high temperature detection sensitivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0024] Figure 1 Dy 3+ Emission spectrum of doped CaWO4 phosphor at room temperature (excitation wavelength λ ex =352nm)( Figure 1 a), and the excitation spectrum at room temperature (emission wavelength λ em =575, 488, 479 and 455nm)( Figure 1 b);

[0025] Figure 2 Dy3+ Excitation spectra of doped CaWO4 phosphor at different temperatures, where the emission wavelength λ em 455nm( Figure 2 a), 479nm( Figure 2 Middle b), 488nm( Figure 2 c) and 575nm( Figure 2 middle d);

[0026] Figure 3 Dy of Example 1 of the present invention 3+ The relationship curve between the peak intensity ratio of the excitation light and the temperature of the doped CaWO4 phosphor at the excitation wavelength λ1=352nm: ( Figure 3 a) ( Figure 3 b) ( Figure 3 c) and ( Figure 3 d), where the solid line is the fitting curve.

[0027] Figure 4 Dy of Example 1 of the present invention 3+ Temperature sensing sensitivity curves of doped CaWO4 phosphors based on different excitation intensity ratios ( Figure 4 a), and the excitation intensity ratio stability under two heating and cooling cycles ( Figure 4 b);

[0028] Figure 5 Dy of Comparative Example 1 of the present invention 3+ Doped CaWO4 phosphor at excitation wavelength λ 1’ = Schematic diagram of the excitation peak integrated area range at 352 nm ( Figure 5 In a), at the excitation wavelength λ 1’ = Relationship curve between different emission peak integrated intensity ratio and temperature at 352nm ( Figure 5 b), and the temperature sensing sensitivity curve based on different excitation intensity ratios at this wavelength ( Figure 5 c);

[0029] Figure 6 Dy of Comparative Example 2 of the present invention 3+ Blue light emission spectra of doped CaWO4 phosphor at different temperatures ( Figure 6 a), and the ratio of the two blue light fluorescence intensities (I B1 / I B2 ) vs. temperature and temperature sensor sensitivity curve ( Figure 6 b);

[0030] Figure 7Dy of Example 2 of the present invention 3+ The relationship curve between the peak intensity ratio of the excitation light and the temperature of the doped CaWO4 phosphor at the excitation wavelength λ2 = 326nm ( Figure 7 a), and the temperature sensing sensitivity curve based on different excitation intensity ratios at this wavelength ( Figure 7 b);

[0031] Figure 8 Dy of Example 3 of the present invention 3+ The relationship between the peak intensity ratio of the excitation light and the temperature of the CaWO4 phosphor doped at the excitation wavelength λ3 = 366nm ( Figure 8 a), and the temperature sensing sensitivity curve based on different excitation intensity ratios at this wavelength ( Figure 8 b);

[0032] Fig. 9 Dy of Example 4 of the present invention 3+ The relationship curve between the peak intensity ratio of the excitation light and the temperature of the CaWO4 phosphor doped with the excitation wavelength λ4 = 388nm ( Fig. 9 a), and the temperature sensing sensitivity curve based on different excitation intensity ratios at this wavelength ( Fig. 9 (b) DETAILED DESCRIPTION

[0033] The present invention is described in detail below by specific examples, but the protection scope of the present invention is not limited. Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the experimental equipment, materials, reagents, etc. used can be obtained from commercial channels.

[0034] The present invention uses rare earth Dy 3+ Doped CaWO4 phosphor is taken as an example, by measuring the rare earth Dy 3+ The excitation light intensity of the doped CaWO4 phosphor at a specific emission light wavelength adopts four different excitation intensity ratio schemes as embodiments to achieve a quantitative relationship between the excitation intensity ratio corresponding to two different emission wavelengths and the temperature.

[0035] Figure 1 a is Dy of the present invention 3+ Doped CaWO4 phosphor at excitation wavelength λ ex = Room temperature emission spectrum at 352nm. It can be seen that under 352nm ultraviolet light excitation, Dy 3+ The doped CaWO4 phosphor emits blue light with central wavelengths of 455, 479 and 488 nm and yellow light at 575 nm in the 435-625 nm band, corresponding to Dy 3+ Ionic 4 I 15 / 2 → 6 H15 / 2 , 4 F 9 / 2 → 6 H 15 / 2 and 4 F 9 / 2 → 6 H 13 / 2 Transition, where the emission peaks at central wavelengths of 479 and 488 nm are 4 F 9 / 2Stark level splitting transition to the ground state 6 H 15 / 2 Double emission peaks at energy levels. Figure 1 Wherein b is Dy of the present invention 3+ Doped CaWO4 phosphor has an emission wavelength of λ em = = 575, 488, 479 and 455nm. It can be seen that the excitation spectra at different emission wavelengths have the same waveform, but the excitation intensity is different. The excitation spectra of the four emission wavelengths all have multiple Dy 3+ The excitation peaks of Dy 3+ of 6 H 15 / 2 → 6 P 3 / 2 , 6 H 15 / 2 → 6 P 5 / 2 , 6 H 15 / 2 → 4 M 19 / 2 and 6 H 15 / 2 → 4 I 13 / 2 Stimulate transition.

[0036] Figure 2 Dy 3+ Doped CaWO4 phosphor has an emission wavelength of λ em The temperature-dependent excitation spectra at 455, 479, 488, and 575 nm are shown. It can be seen that, corresponding to the excitation spectrum of each emission wavelength, as the temperature increases, Dy 3+ The excitation peak position of the ion does not change, but the excitation intensity changes significantly. em =455nm excitation spectrum, its excitation intensity gradually increases with the increase of temperature, while the other three emission wavelengths λ em = The excitation spectra of 479, 488 and 575 nm, their excitation intensities gradually decrease with increasing temperature.

[0037] Example 1

[0038] Figure 3 The Dy 3+ Doped CaWO4 phosphor at excitation wavelength λ1 = 352nm and The relationship between the four excitation peak intensity ratios and temperature. and The variation of the three excitation peak intensity ratios R with temperature T is expressed by the formula

[0039]

[0040] To fit, The variation of intensity ratio R with temperature can be expressed by the formula

[0041]

[0042] Fitting was performed to obtain the fitting constants a, b and c in equations (1) and (2). As can be seen from the figure, in the temperature range of 300-650K, the ratio of the four excitation peak intensities and temperature all showed a good quantitative relationship, indicating that the Dy 3+ The excitation intensity ratio of ions and temperature can show excellent temperature sensing characteristics in a wide temperature range.

[0043] According to the definition of absolute temperature sensor sensitivity S a =dR / dT, the absolute temperature sensor sensitivity S corresponding to equation (1) and equation (2) a Can be expressed as

[0044]

[0045]

[0046] Figure 4 Where a is the Dy based on the formula (3) and (4) 3+ Doped CaWO4 phosphor and Temperature sensing sensitivity curves of four excitation peak intensity ratios. It can be seen from the figure that in the entire experimental temperature range based on Dy 3+ The temperature measurement technologies based on different excitation intensity ratios all have good temperature sensing sensitivity. and The sensitivity of the three excitation peak intensity ratio temperature measurement techniques gradually increases with the increase of temperature, while the The sensitivity of the temperature measurement scheme based on the excitation peak intensity ratio gradually decreases as the temperature rises. (or ) has similar and optimal temperature sensing characteristics. This is because λ em =479 and 488nm 4 F 9 / 2 Stark level splitting transition to the ground state 6 H 15 / 2 The double emission peak of the energy level, so Dy 3+ Doped CaWO4 phosphor and The temperature sensing of the excitation peak intensity ratio has a similar temperature sensing sensitivity. At 650K, it corresponds to The temperature measurement technique based on the ratio of the excitation peak intensity has the maximum sensitivity S a =30.43*10 -4 K -1 (Table 1).

[0047] Figure 4 b gives Dy 3+ Doped CaWO4 phosphor and The variation curves of the four excitation peak intensity ratios under two temperature rise and fall cycles. As can be seen from the figure, the variation of the four excitation peak intensity ratios with temperature shows good repeatability and stability, indicating that Dy 3+ The quantitative relationship between the excitation peak intensity ratio and temperature also has good repeatability and stability.

[0048] Comparative Example 1

[0049] In Example 1, Dy 3+ Doped CaWO4 phosphor at excitation wavelength λ1 = 352nm and The four excitation intensity ratios are based on the emission wavelength λ em The peak intensities at λ1=352nm at 455, 479, 488 and 575nm are respectively. In order to compare with the widely used integrated area intensity, the inventors also used the excitation peak integrated intensity with a central wavelength of 352nm in the excitation spectrum for calculation.

[0050] Figure 5 Where a gives Dy 3+ Doped CaWO4 phosphor corresponds to the excitation wavelength λ 1’ =The excitation peak integral range when 352nm is used, and the integral area of ​​the excitation peak in the 342-360nm band is used as the excitation light intensity to calculate the excitation intensity ratio. Figure 5 In b, four excitation intensity ratios calculated using the excitation peak area at a central wavelength of 352 nm are given ( and ) changes with temperature, where and The variation of the three excitation intensity ratios R with temperature can be fitted by the empirical formula (1): The variation of the intensity ratio R with temperature can be fitted by formula (2). It can be seen from the figure that the excitation intensity ratio calculated based on the integral intensity of the excitation peak also exhibits excellent temperature sensing characteristics with temperature. Figure 5 Where c gives the calculated value according to equation (3) and equation (4) Figure 5 b shows the temperature sensing sensitivity curves of the corresponding four excitation intensity ratio schemes. The variation of the temperature sensing sensitivity with temperature based on these four excitation intensity ratio schemes is completely consistent with that in Example 1, and based on The temperature measurement scheme of the excitation peak integrated intensity ratio has the maximum sensitivity S at 650K a =28.53*10 -4 K -1 (Table 1) is also basically the same as that of Example 1.

[0051] By comparing Example 1 and Comparative Example 1, it can be seen that no matter whether the peak intensity of the excitation peak is used as the basis for calculating the intensity ratio in Example 1 or the integral area of ​​the excitation peak is used as the basis for calculating the intensity ratio in Comparative Example 1, the obtained excitation intensity ratio and temperature are in accordance with a consistent quantitative relationship, and the obtained temperature sensing sensitivity is also basically the same. Since the integral intensity of the excitation peak calculated in Comparative Example 1 requires the complete measurement of the entire excitation spectrum, while the peak intensity of the excitation peak used in Example 1 does not require a complete excitation spectrum, the corresponding excitation peak intensity can be obtained by simply setting the emission wavelength and the excitation wavelength during measurement. Therefore, compared with Comparative Example 1, Example 1 is simpler, more convenient and faster in actual temperature measurement applications.

[0052] Comparative Example 2

[0053] In order to compare with the previous work based on Dy 3+ The inventors also conducted optical temperature sensing of Dy 3+ Doped CaWO4 phosphor based on Dy 3+ Study on the optical temperature sensing properties of two blue light intensity ratios.

[0054] Figure 6 Where a gives Dy 3+ The doped CaWO4 phosphor corresponds to the range of 440-505nm at different temperatures 4 I 15 / 2 → 6 H 15 / 2 and 4 F 9 / 2 → 6 H15 / 2 It can be seen that with the increase of temperature, Dy 3+ The ion luminescence peak position did not change significantly, but the luminescence intensity did change. 3+ ion 4 I 15 / 2 → 6 H 15 / 2 Transition blue light intensity I B1 As the temperature increases, it gradually increases, and the corresponding Dy 3+ ion 4 F 9 / 2 → 6 H 15 / 2 Another blue light intensity of transition I B2 It gradually weakens as the temperature rises. Figure 6 b in Dy 3+ Dy in doped CaWO4 phosphor 3+ The fluorescence intensity ratio of the two blue lights of the ion (I B1 / I B2 ) and temperature, where the solid line is the fitting result of formula (2). As can be seen from the figure, the fluorescence intensity ratio of the two blue lights (I B1 / I B2 ) and temperature also exhibits good temperature sensing characteristics. Figure 6 The temperature sensing sensitivity curve (dashed line) calculated by equation (4) is also given in b. Its sensitivity increases first and then decreases with increasing temperature, and has the maximum sensitivity S at 638K. a =10.6*10 -4 K -1 .

[0055] By comparison Figure 4 A and Figure 6 As can be seen in b, compared with the traditional Dy-based 3+ The temperature measurement technology based on the ratio of two blue light intensities, the Dy 3+ The sensitivity of the excitation peak intensity is about 3 times higher than that of the temperature measurement technology, indicating that the Dy 3+ Compared with the traditional method based on Dy 3+ The fluorescence intensity ratio temperature measurement method has a higher temperature detection sensitivity.

[0056] Example 2

[0057] Figure 7 a shows the Dy of the present invention 3+ Doped CaWO4 phosphor at excitation wavelength λ2 = 326nm and The relationship between the four excitation peak intensity ratios and temperature. and The variation of the three excitation peak intensity ratios R with temperature can be fitted by the empirical formula (1): The variation of the intensity ratio R with temperature can be fitted by formula (2). As can be seen from the figure, in the temperature range of 300-650K, the four excitation peak intensity ratios show a good quantitative relationship with temperature, indicating that Dy 3+ The excitation intensity ratio and temperature show excellent temperature sensing characteristics in a wide temperature range.

[0058] Figure 7 Where b is the Dy based on the equation (3) and (4) 3+ Doped CaWO4 phosphor and Temperature sensing sensitivity curves of four excitation peak intensity ratios. It can be seen from the figure that in the entire experimental temperature range based on Dy 3+ The temperature measurement technologies with different excited state intensity ratio schemes all have good temperature sensing sensitivity. and The sensitivity of the three excitation peak intensity ratio temperature measurement techniques gradually increases with the increase of temperature, while the The sensitivity of the temperature measurement scheme based on the excitation peak intensity ratio gradually decreases as the temperature rises. (or ) has similar and optimal temperature sensing characteristics. At 650K, it corresponds to The temperature measurement technique based on the ratio of the excitation peak intensity has the maximum sensitivity S a =29.32*10 -4 K -1 (Table 1) Compared with Example 1, it can be seen that the temperature sensing sensitivity curve is basically consistent with that of Example 1, and the maximum sensitivity value is also basically the same as that of Example 1.

[0059] Example 3

[0060] Figure 8 a shows the Dy of the present invention 3+ Doped CaWO4 phosphor at excitation wavelength λ3 = 366nm and The relationship between the four excitation peak intensity ratios and temperature. and The variation of the three excitation peak intensity ratios R with temperature can be fitted by the empirical formula (1): The variation of the intensity ratio R with temperature can be fitted by formula (2). As can be seen from the figure, in the temperature range of 300-650K, the four excitation peak intensity ratios show a good quantitative relationship with temperature, indicating that Dy 3+ The excitation intensity ratio and temperature show excellent temperature sensing characteristics in a wide temperature range.

[0061] Figure 8 Where b is the Dy based on the equation (3) and (4) 3+ Doped CaWO4 phosphor and Temperature sensing sensitivity curves of four excitation peak intensity ratios. It can be seen from the figure that in the entire experimental temperature range based on Dy 3+ The temperature measurement technologies with different excited state intensity ratio schemes all have good temperature sensing sensitivity. and The sensitivity of the three excitation peak intensity ratio temperature measurement techniques gradually increases with the increase of temperature, while the The sensitivity of the temperature measurement scheme based on the excitation peak intensity ratio gradually decreases as the temperature rises. (or ) has similar and optimal temperature sensing characteristics. At 650K, it corresponds to The temperature measurement technique based on the ratio of the excitation peak intensity has the maximum sensitivity S a =26.86*10 -4 K -1 (Table 1) Compared with Example 1 and Example 2, it can be seen that the temperature sensing sensitivity curve is basically consistent with that of Example 1 and Example 2, and the maximum sensitivity value is also basically the same as that of Example 1 and Example 2.

[0062] Example 4

[0063] Fig. 9 a shows the Dy of the present invention 3+ Doped CaWO4 phosphor at excitation wavelength λ4 = 388nm and The relationship between the four excitation peak intensity ratios and temperature. and The variation of the three excitation peak intensity ratios R with temperature can be fitted by the empirical formula (1): The variation of the intensity ratio R with temperature can be fitted by formula (2). As can be seen from the figure, in the temperature range of 300-650K, the four excitation peak intensity ratios show a good quantitative relationship with temperature, indicating that Dy 3+ The excitation intensity ratio and temperature show excellent temperature sensing characteristics in a wide temperature range.

[0064] Fig. 9 Where b is the Dy based on the equation (3) and (4) 3+ Doped CaWO4 phosphor and Temperature sensing sensitivity curves of four excitation peak intensity ratios. It can be seen from the figure that in the entire experimental temperature range based on Dy 3+ The temperature measurement technologies with different excited state intensity ratio schemes all have good temperature sensing sensitivity. and The sensitivity of the three excitation peak intensity ratio temperature measurement techniques gradually increases with the increase of temperature, while the The sensitivity of the temperature measurement scheme based on the excitation peak intensity ratio gradually decreases as the temperature rises. (or ) has similar and optimal temperature sensing characteristics. At 650K, it corresponds to The temperature measurement technique based on the ratio of the excitation peak intensity has the maximum sensitivity S a =27.41*10 -4 K -1 (Table 1) Compared with Example 1, Example 2 and Example 3, it can be seen that the temperature sensing sensitivity curve is basically consistent with that of Example 1, Example 2 and Example 3, and the maximum sensitivity value is also basically the same as that of Example 1, Example 2 and Example 3.

[0065] Table 1 summarizes the maximum temperature sensing sensitivity values ​​and corresponding temperatures of five excitation intensity ratio schemes of Examples 1-4 and Comparative Example 1.

[0066] Table 1

[0067]

[0068] It can be seen from the table that, under the same excitation intensity ratio scheme, the use of different excitation wavelengths has no obvious effect on the sensitivity, indicating that the temperature sensing technology based on the excitation intensity ratio proposed in the present invention is independent of the selected excitation wavelength and has good selectivity, and the temperature sensing sensitivity is also not affected by the selected excitation wavelength and has good stability and repeatability.

[0069] Table 2 summarizes the Dy 3+ The maximum temperature sensing sensitivity of the excitation intensity ratio of the doped CaWO4 phosphor and the reported maximum temperature sensing sensitivity data of other Dy-doped material systems based on the fluorescence intensity ratio.

[0070] Table 2

[0071]

[0072] Dy cited in the above table 3+ References for doped luminescent materials are as follows:

[0073] [1]L. Li, F. Qin, Y. Zhou, Y. Zheng, J. Miao, Z. Zhang, Three - energy - level - cascaded strategy for a more sensitive luminescence ratiometric thermometry, Sensors and Actuators A: Physical, 304(2020)111864.

[0074] [2]L. S.R. V. K. E. Glais, B. Viana, M.D. Luminescence temperature sensing in visible and NIR spectral range using Dy 3+ and Nd 3+ doped YNbO4, Sensors and Actuators A: Physical, 270(2018)89 - 96.

[0075] [3]Z. Antic, M.D. Dramicanin, K. Prashanthi, D. Jovanovic, S. Kuzman, T. Thundat, Pulsed Laser Deposited Dysprosium - Doped Gadolinium - Vanadate Thin Films for Noncontact, Self - Referencing Luminescence Thermometry, Advanced materials, 28(2016)7745 - 7752.

[0076] [4]S. V. Lojpur, S.P. Ahrenkiel, J.M. M.D. Non - contact thermometry with Dy 3+doped Gd2Ti2O7 nano-powders, Journal of Luminescence, 170 (2016) 395-400.

[0077] [5]Z.Cao,S.Zhou,G.Jiang,Y.Chen,C.Duan,M.Yin,Temperature dependentluminescence of Dy 3+ doped BaYF5 nanoparticles for optical thermometry,CurrentApplied Physics,14(2014)1067-1071.

[0078] [6]LMChepyga,E.Hertle,A.Ali,L.Zigan,A.Osvet,CJBrabec,M.Batentschuk,Synthesis and photoluminescent properties of the Dy 3+ doped YSOas a high-temperature thermographic phosphor,Journal of Luminescence,197(2018)23-30.

[0079] [7]Z.Boruc,M.Kaczkan,B.Fetlinski,S.Turczynski,M.Malinowski,BlueEmissions in Dy 3+ Doped Y4Al2O9 Crystals for Temperature Sensing,Opt.Lett.,37(2012)5214-5216.

[0080] As can be seen from the table, the Dy 3+ The maximum temperature sensing sensitivity of the excitation intensity ratio of the doped CaWO4 phosphor is significantly higher than that of the Dy 3+ The temperature sensing sensitivity of the fluorescence intensity ratio of doped CaWO4 is also better than that of other Dy 3+ Doping material system such as Dy 3+ Doping with BaYF5 and Dy 3+ Doped Y2SiO5, compared with Dy based on fluorescence intensity ratio 3+The material systems doped with YNbO4, GdVO4, Gd2Ti2O7 and Y4Al2O9 are on par. 3+ The temperature sensing technology based on ion excitation intensity ratio has higher temperature detection sensitivity.

[0081] The above-described embodiments are only preferred embodiments of the present invention, but not all feasible embodiments of the present invention. For those skilled in the art, any obvious changes made thereto without departing from the principles and spirit of the present invention should be considered to be included in the scope of protection of the claims of the present invention.

Claims

1. A rare earth Dy-based 3+ The temperature detection method of ion excitation intensity ratio is characterized by: The specific steps are: S1.Measure Dy at a fixed temperature 3+ The peak intensities of the excitation light corresponding to the two emission wavelengths A and B of the doped CaWO4 phosphor are recorded as and Wherein i=1, 2, 3 or 4, corresponding to the excitation light of four wavelengths of λ1=352nm, λ2=326nm, λ3=366nm or λ4=388nm, respectively, the wavelength A is specifically 455nm, and the wavelength B is specifically one of 479nm, 488nm or 575nm; S2. Calculate the peak intensity of the excitation light at the above temperature and The ratio of Where i = 1, 2, 3 or 4, corresponding to the excitation light of four wavelengths of λ1 = 352nm, λ2 = 326nm, λ3 = 366nm or λ4 = 388nm respectively; S3. Change Dy 3+ The temperature of the CaWO4 phosphor is repeated, and the above steps S1 and S2 are repeated to obtain the peak intensity ratio of the excitation light. Relationship curve with temperature T; S4. Using formula The curve obtained in step S3 is fitted to obtain the values ​​of fitting constants a, b, and c, and then the Dy 3+ Quantitative relationship between the excitation intensity ratio of doped CaWO4 phosphor and temperature, where R is the excitation light peak intensity ratio and T is the temperature.

2. The rare earth Dy based catalyst according to claim 1 3+ The temperature detection method of ion excitation intensity ratio is characterized by: The temperature in steps S1 and S2 is any temperature value within the range of 305 to 650K.

3. The rare earth Dy based catalyst according to claim 1 3+ The temperature detection method of ion excitation intensity ratio is characterized by: The temperature in step S3 is any temperature value within the range of 305 to 650 K which is different from the temperatures in steps S1 and S2.

Images