CN114214069B - Core-shell double-doped nanoparticle material for improving sensitivity of non-contact temperature sensor and preparation method and application thereof - Google Patents
Core-shell double-doped nanoparticle material for improving sensitivity of non-contact temperature sensor and preparation method and application thereof Download PDFInfo
- Publication number
- CN114214069B CN114214069B CN202111559055.2A CN202111559055A CN114214069B CN 114214069 B CN114214069 B CN 114214069B CN 202111559055 A CN202111559055 A CN 202111559055A CN 114214069 B CN114214069 B CN 114214069B
- Authority
- CN
- China
- Prior art keywords
- nayf
- core
- temperature
- shell
- nano particles
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000002105 nanoparticle Substances 0.000 title claims abstract description 121
- 239000011258 core-shell material Substances 0.000 title claims abstract description 60
- 230000035945 sensitivity Effects 0.000 title claims abstract description 49
- 238000002360 preparation method Methods 0.000 title claims abstract description 13
- 239000000463 material Substances 0.000 title abstract description 27
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims abstract description 69
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 48
- CCCMONHAUSKTEQ-UHFFFAOYSA-N octadecene Natural products CCCCCCCCCCCCCCCCC=C CCCMONHAUSKTEQ-UHFFFAOYSA-N 0.000 claims abstract description 30
- 239000000243 solution Substances 0.000 claims abstract description 28
- WRIDQFICGBMAFQ-UHFFFAOYSA-N (E)-8-Octadecenoic acid Natural products CCCCCCCCCC=CCCCCCCC(O)=O WRIDQFICGBMAFQ-UHFFFAOYSA-N 0.000 claims abstract description 20
- LQJBNNIYVWPHFW-UHFFFAOYSA-N 20:1omega9c fatty acid Natural products CCCCCCCCCCC=CCCCCCCCC(O)=O LQJBNNIYVWPHFW-UHFFFAOYSA-N 0.000 claims abstract description 20
- QSBYPNXLFMSGKH-UHFFFAOYSA-N 9-Heptadecensaeure Natural products CCCCCCCC=CCCCCCCCC(O)=O QSBYPNXLFMSGKH-UHFFFAOYSA-N 0.000 claims abstract description 20
- ZQPPMHVWECSIRJ-UHFFFAOYSA-N Oleic acid Natural products CCCCCCCCC=CCCCCCCCC(O)=O ZQPPMHVWECSIRJ-UHFFFAOYSA-N 0.000 claims abstract description 20
- 239000005642 Oleic acid Substances 0.000 claims abstract description 20
- QXJSBBXBKPUZAA-UHFFFAOYSA-N isooleic acid Natural products CCCCCCCC=CCCCCCCCCC(O)=O QXJSBBXBKPUZAA-UHFFFAOYSA-N 0.000 claims abstract description 20
- ZQPPMHVWECSIRJ-KTKRTIGZSA-N oleic acid Chemical compound CCCCCCCC\C=C/CCCCCCCC(O)=O ZQPPMHVWECSIRJ-KTKRTIGZSA-N 0.000 claims abstract description 20
- 238000010438 heat treatment Methods 0.000 claims abstract description 19
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 claims abstract description 18
- 229910052761 rare earth metal Inorganic materials 0.000 claims abstract description 17
- 238000005406 washing Methods 0.000 claims abstract description 10
- 239000007864 aqueous solution Substances 0.000 claims abstract description 9
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 36
- 239000000523 sample Substances 0.000 claims description 22
- 238000000034 method Methods 0.000 claims description 19
- 238000003756 stirring Methods 0.000 claims description 19
- 229910052786 argon Inorganic materials 0.000 claims description 18
- 238000001816 cooling Methods 0.000 claims description 12
- -1 lanthanide rare earth ions Chemical class 0.000 claims description 7
- 239000007789 gas Substances 0.000 claims description 5
- 229910052747 lanthanoid Inorganic materials 0.000 claims description 5
- 238000002156 mixing Methods 0.000 claims description 4
- 238000001291 vacuum drying Methods 0.000 claims description 3
- 150000001335 aliphatic alkanes Chemical class 0.000 claims 1
- 239000003054 catalyst Substances 0.000 claims 1
- 238000009529 body temperature measurement Methods 0.000 abstract description 19
- 230000003287 optical effect Effects 0.000 abstract description 10
- 239000013307 optical fiber Substances 0.000 abstract description 8
- 229910017855 NH 4 F Inorganic materials 0.000 abstract description 5
- 238000001035 drying Methods 0.000 abstract description 2
- 238000011160 research Methods 0.000 abstract description 2
- 238000006243 chemical reaction Methods 0.000 description 35
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 14
- 230000005284 excitation Effects 0.000 description 12
- 230000007704 transition Effects 0.000 description 12
- 239000010410 layer Substances 0.000 description 9
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 8
- 239000013078 crystal Substances 0.000 description 8
- 230000003247 decreasing effect Effects 0.000 description 8
- 239000000047 product Substances 0.000 description 8
- 238000002441 X-ray diffraction Methods 0.000 description 6
- 230000008859 change Effects 0.000 description 6
- 238000005516 engineering process Methods 0.000 description 6
- 239000000835 fiber Substances 0.000 description 6
- 150000002500 ions Chemical class 0.000 description 6
- 239000002245 particle Substances 0.000 description 6
- 238000012360 testing method Methods 0.000 description 6
- 230000007547 defect Effects 0.000 description 5
- 238000009826 distribution Methods 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 150000002910 rare earth metals Chemical class 0.000 description 5
- 238000001857 fluorescence decay curve Methods 0.000 description 4
- 238000002189 fluorescence spectrum Methods 0.000 description 4
- 230000001376 precipitating effect Effects 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 238000001228 spectrum Methods 0.000 description 4
- 238000010521 absorption reaction Methods 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 3
- 239000007795 chemical reaction product Substances 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 230000001419 dependent effect Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- IIEWJVIFRVWJOD-UHFFFAOYSA-N ethyl cyclohexane Natural products CCC1CCCCC1 IIEWJVIFRVWJOD-UHFFFAOYSA-N 0.000 description 3
- 238000002173 high-resolution transmission electron microscopy Methods 0.000 description 3
- 238000004020 luminiscence type Methods 0.000 description 3
- 239000011259 mixed solution Substances 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 230000005855 radiation Effects 0.000 description 3
- 239000011541 reaction mixture Substances 0.000 description 3
- 238000012546 transfer Methods 0.000 description 3
- 238000005054 agglomeration Methods 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- 238000012512 characterization method Methods 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 229910052691 Erbium Inorganic materials 0.000 description 1
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 1
- NIPNSKYNPDTRPC-UHFFFAOYSA-N N-[2-oxo-2-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)ethyl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C(CNC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F)N1CC2=C(CC1)NN=N2 NIPNSKYNPDTRPC-UHFFFAOYSA-N 0.000 description 1
- AFCARXCZXQIEQB-UHFFFAOYSA-N N-[3-oxo-3-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propyl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C(CCNC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F)N1CC2=C(CC1)NN=N2 AFCARXCZXQIEQB-UHFFFAOYSA-N 0.000 description 1
- 238000003917 TEM image Methods 0.000 description 1
- 229910052775 Thulium Inorganic materials 0.000 description 1
- 229910052769 Ytterbium Inorganic materials 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000012190 activator Substances 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 239000012300 argon atmosphere Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 239000012295 chemical reaction liquid Substances 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000012792 core layer Substances 0.000 description 1
- 238000005090 crystal field Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
- 230000036571 hydration Effects 0.000 description 1
- 238000006703 hydration reaction Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 150000002602 lanthanoids Chemical class 0.000 description 1
- 230000003211 malignant effect Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 238000001000 micrograph Methods 0.000 description 1
- 239000002086 nanomaterial Substances 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000005192 partition Methods 0.000 description 1
- XOFYZVNMUHMLCC-ZPOLXVRWSA-N prednisone Chemical compound O=C1C=C[C@]2(C)[C@H]3C(=O)C[C@](C)([C@@](CC4)(O)C(=O)CO)[C@@H]4[C@@H]3CCC2=C1 XOFYZVNMUHMLCC-ZPOLXVRWSA-N 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 238000000638 solvent extraction Methods 0.000 description 1
- 239000006228 supernatant Substances 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 238000004861 thermometry Methods 0.000 description 1
- 239000002341 toxic gas Substances 0.000 description 1
- 230000005472 transition radiation Effects 0.000 description 1
- 238000002834 transmittance Methods 0.000 description 1
- 238000013316 zoning Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
- C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
- C09K11/77—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals
- C09K11/7766—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals containing two or more rare earth metals
- C09K11/7772—Halogenides
- C09K11/7773—Halogenides with alkali or alkaline earth metal
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K11/00—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00
- G01K11/32—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00 using changes in transmittance, scattering or luminescence in optical fibres
Landscapes
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
- Investigating Or Analysing Materials By The Use Of Chemical Reactions (AREA)
Abstract
The invention discloses a core-shell for improving the sensitivity of a non-contact temperature sensorThe double-doped nanoparticle material and the preparation method and the application thereof comprise the following steps: (1) To Tm-containing 3+ Adding oleic acid and octadecene into the rare earth ion aqueous solution, and dissolving; (2) Will contain NaOH and NH 4 F, adding the methanol solution into the step (1), and heating; (3) Washing the nano particles generated in the step (2) and dispersing the nano particles in cyclohexane; (4) To Er-containing 3+ Adding oleic acid and octadecene into the rare earth ion aqueous solution, and dissolving; (5) Will contain NaOH and NH 4 F, adding the methanol solution and the solution obtained in the step (3) into the step (4), and heating; (6) Washing and drying the generated nano particles to obtain the core-shell structure nano particles. The invention also researches the optical temperature sensing characteristic of the thermocouple energy level, constructs a temperature measurement platform and evaluates the feasibility and reliability of the application of the thermocouple energy level in the optical fiber temperature sensor.
Description
Technical Field
The invention belongs to the technical field of material preparation, and particularly relates to a core-shell double-doped nanoparticle material for improving the sensitivity of a non-contact temperature sensor, and a preparation method and application thereof.
Background
As one of the basic physical parameters, temperature has become an important measure for scientific research work and industrial production. Among the numerous temperature measuring methods, the rare earth-based non-contact optical temperature sensor is attracting attention, and compared with the traditional temperature measuring method, the method is only related to the fluorescence characteristic of the material, so that the dependence of the traditional temperature measuring method on the environment can be effectively avoided. In particular, the optical temperature measurement technology based on the rare earth up-conversion Fluorescence Intensity Ratio (FIR) has potential application in metallurgy, catalysis, high-temperature synthesis, material processing, biological cells and the like, and has wide applicability to a malignant environment and a fast moving object, so that the optical temperature measurement technology is called one of the very promising temperature measurement technologies. Furthermore, the rare earth element has a very rich energy level structure, and different rare earth luminescent ions are doped in a partitioning way through shell cladding, so that high-sensitivity temperature measurement is realized.
In the aspect of FIR temperature measurement, the up-conversion fluorescence intensity ratio based on two thermocouple energy levels is not influenced by factors such as spectrum loss, laser power intensity fluctuation and the like, so that high-sensitivity temperature measurement is realized. In the traditional temperature measuring material using oxide as a matrix, not only the up-conversion fluorescence intensity is low, but also the temperature measuring sensitivity is low, and the current social requirement cannot be met, so that the development of a luminescent material with high sensitivity and high fluorescence intensity is urgently needed. Among the lanthanide matrixes, fluoride has the advantages of low phonon energy, high transmittance, good stability and the like, and NaYF 4 Phonon energy of only 360cm -1 Thus NaYF 4 Becomes one of the most ideal matrix materials. Tm (Tm) 3+ And Er 3+ As rare earth element with higher luminous efficiency, the rare earth element becomes an ideal activator for nano particles. Yb 3+ Matching with 980nm excitation light energy, and becoming an ideal sensitizer for nano particles. And a 980nm laser in the market is high-efficiency and low-cost, and provides reliable excitation energy for up-conversion of the nanomaterial. Thus, naYF 4 :Yb 3+ /Tm 3+ And NaYF 4 :Yb 3+ /Er 3+ Nanoparticles are presently the more desirable upconversion nanoparticles. However, the light-emitting device has certain limitations, such as a large number of surface defects, a large specific surface area, etc., so that the light emission is not strong and the up-conversion efficiency is not high. Therefore, a material that can improve both the luminous intensity and the sensitivity has been studied.
In the existing rare earth-based non-contact temperature measurement materials, most of the material structures only have a nuclear layer, and are not coated with a shell layer, so that surface defects are increased, fluorescence intensity is weakened, and temperature measurement sensitivity is low.
Disclosure of Invention
In order to further solve the defects and the shortcomings of the prior temperature measurement technology, the invention provides a core-shell double-doped nanoparticle material for improving the sensitivity of a non-contact temperature sensor, and a preparation method and application thereof.
In order to achieve the above purpose, the present invention provides the following technical solutions:
the technical scheme is as follows: the preparation method of the core-shell double-doped up-conversion nanoparticle material for improving the sensitivity of the non-contact temperature sensor comprises the following steps of:
(1) By mixing lanthanide rare earth ions Ln 3+ Magnetically stirring the aqueous solution, stirring to evaporate water in the solution, adding oleic acid and octadecene after the water is completely evaporated, heating to 120 ℃ under the protection of argon for 30min to remove water in OA and ODE, then raising the temperature to 150-160 ℃ for 60min, and cooling to room temperature; the Ln 3+ Is Y 3+ ，Yb 3+ And Tm 3+ The method comprises the steps of carrying out a first treatment on the surface of the Preferably 160 ℃;
(2) Adding NaOH and NH into the solution obtained in the step (1) 4 F, stirring the methanol solution, heating to 100-120 ℃ (preferably 100 ℃) under the protection of argon, after methanol is removed completely, raising the temperature to 280-310 ℃, keeping for 1-2h, and cooling to room temperature to obtain nano particles A; the NaOH and NH 4 F, 5mL of methanol solution;
(3) Washing the obtained nano particles A, and dissolving in cyclohexane to obtain the naYF with the naked core structure 4 :Yb 3+ /Tm 3+ A nanoparticle;
(4) By mixing lanthanide rare earth ions Ln 3+ Magnetically stirring the aqueous solution, stirring to evaporate water in the solution, adding oleic acid and octadecene after the water is completely evaporated, heating to 120 ℃ under the protection of argon for 30min, then raising the temperature to 150-160 ℃ (preferably 160 ℃) for 60min, and cooling to room temperature; the Ln 3+ Is Y 3+ ，Yb 3+ And Er 3+ ；
(5) Will contain NaOH and NH 4 Methanol solution of F and bare nuclear structure NaYF dispersed in cyclohexane in step (3) 4 :Yb 3+ /Tm 3+ Adding the nano particles into the solution obtained in the step (4), stirring, heating to 100-120 ℃ (preferably 100 ℃) under the protection of argon, after methanol and cyclohexane are removed completely, raising the temperature to 280-310 ℃, keeping for 1-2h, and cooling to room temperature to obtain nano particles B; the NaOH and NH 4 F, 5mL of methanol solution;
(6) Washing the obtained nano particles B, and then vacuum drying for 24 hours to obtain the core-shell NaYF 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ And (3) nanoparticles. The drying temperature was 50 ℃.
Further, step (1) said Y 3+ ，Yb 3+ And Tm 3+ Respectively selected from YCl 3 ·6H 2 O、YbCl 3 ·6H 2 O and TmCl 3 ·6H 2 O; step (4) the Y 3+ ，Yb 3+ And Er 3+ Is respectively selected from YCl 3 ·6H 2 O、YbCl 3 ·6H 2 O and ErCl 3 ·6H 2 O。
Further, the Y 3+ ，Yb 3+ And Tm 3+ The molar ratio of (2) is 81.5:18:0.5; the Y is 3+ ，Yb 3+ And Er 3+ The molar ratio of (1.3-81.7) is 18 (0.3-0.7).
Further, the volume ratio of the oleic acid to the octadecene in the step (1) is (3.5-4): 7-8; the volume ratio of the oleic acid to the octadecene in the step (4) is (7-8) to (14-16).
Further, step (2) the Y 3+ With NaOH and NH 4 The molar ratio of F is 1 (3.0-3.1) (4.9-5.0); step (5) the Y 3+ With NaOH and NH 4 F is 1 (3.0-3.1): (4.9-5.0) in terms of molar ratio, Y in this step 3+ The content is Y in the step (4) 3+ The content is as follows.
Further, after the methanol is removed completely in the step (2), the reaction temperature is raised to 300 ℃ and kept for 1.5h; after methanol and cyclohexane are removed completely in the step (4), the reaction temperature is raised to 300 ℃ and maintained for 1.5h.
The washing steps in the step (3) and the step (6) comprise: adding excessive absolute ethyl alcohol into a reaction system, precipitating nano particles, centrifugally separating, removing supernatant, dispersing the obtained nano particles in cyclohexane, then adding absolute ethyl alcohol to wash a product, centrifugally separating, and repeating the steps for three times.
The second technical scheme is as follows: the preparation methodThe obtained core-shell structure NaYF 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ Up-converting the nanoparticles.
Further, the Er 3+ The doping mole amount of (2) is 0.3-0.7%.
The technical scheme is as follows: core-shell structure NaYF 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ Use of nanoparticles as probes.
Further, the core-shell structure NaYF 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ The method for detecting the temperature by using the nanoparticle probe comprises the following steps:
(1) Core-shell NaYF structure 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ The nanoparticle powder is adsorbed on the end face of the optical fiber and used as a temperature sensing probe of the sensor;
(2) Excitation light from the 980nm laser propagates along the fiber to the wavelength division multiplexer;
(3) Excited core-shell NaYF 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ The nanoparticle generates up-converted fluorescence that will pass along the fiber through the wavelength division multiplexer and be received by the spectrometer analyzer for analysis;
(4) By recording the up-conversion fluorescence intensity of 700nm and 646nm emission peaks of the probe under the real-time temperature change of 295K to 495K, the standard temperature is taken as the abscissa, and the formula is adopted
The measured temperature is calculated as ordinate and the feasibility of the sensor is evaluated.
The non-contact type core-shell double-doped up-conversion nanoparticle probe disclosed by the invention is high in sensitivity, low in power and capable of being excited by near infrared light, does not cause heat generation or damage of a sample, can be used in the field of accurate temperature measurement, and provides a new thought for a non-contact type optical temperature sensor on a future nanometer scale.
Compared with the prior art, the invention has the beneficial effects that:
(1) The raw materials used in the invention are inorganic salts, and toxic gas can not be generated in the preparation process, so that the preparation method is environment-friendly. The prepared nano particles are orderly arranged, have uniform size distribution and no agglomeration phenomenon, and have a shape similar to a hexagonal structure; (2) The invention prepares the optical temperature sensor by the core-shell double-doped nano particles, and the sensitivity of the sensor is very high and obviously higher than most of the prior Tm-based temperature sensors 3+ 、Er 3+ Is a rare earth material; (3) The invention can utilize the fluorescence intensity ratio of 700nm and 646nm of the emission peak, and the maximum absolute sensitivity and the maximum relative sensitivity are respectively up to 0.0250K in the temperature range of 295K-495K -1 And 2.155% K -1 All have higher sensitivity than other thermocouple energy levels, which would have potential application in optical temperature sensors; (4) Adopts a core-shell structure NaYF 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ The up-conversion nano particles are used as optical fiber temperature sensors, and the probe material is feasible, reliable and recyclable.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 (a) shows a bare core structure NaYF prepared in example 1 of the present invention 4 :Yb 3+ /Tm 3+ (18/0.5 mol%) NaYF of bare core structure 4 :Yb 3+ /Er 3+ (18/0.5 mol%) and core-shell NaYF 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3 + /Er 3+ (18/xmol%) (x=0.3/0.5/0.7%) XRD pattern of the nanoparticle; (b) An XRD local enlargement of the crystal face of the nanoparticle (201);
FIG. 2 is a LR-TEM, HR-TEM and DLS image of nanoparticles prepared according to example 1 of the present inventionWherein (a), (b) and (c) are respectively bare core structure NaYF 4 :Yb 3+ /Tm 3+ (18/0.5 mol%) LR-TEM, HR-TEM and DLS images, (d), (e), (f) are core-shell NaYF respectively 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) LR-TEM, HR-TEM and DLS profiles of nanoparticles;
FIG. 3 is a TEM energy spectrum and basal scan of up-converted nanoparticles of the present invention;
FIG. 4 (a) is a bare core structure NaYF 4 :Yb 3+ /Tm 3+ (18/0.5 mol%) NaYF of bare core structure 4 :Yb 3+ /Er 3+ (18/0.5 mol%) and core-shell NaYF 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ Fluorescence spectrum of (18/0.5 mol%) nanoparticle (laser: 980nm, power density: 7.5W/cm) -2 ) The method comprises the steps of carrying out a first treatment on the surface of the (b) A change trend graph of the sum of up-conversion fluorescence integral intensities of different samples; (c) is a chromaticity diagram of different samples; (d) Is of a core-shell structure NaYF 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/xmol%) (x=0.3/0.5/0.7%) fluorescence spectrum of nanoparticle (laser: 980nm, power density: 7.5W/cm) -2 ) The method comprises the steps of carrying out a first treatment on the surface of the (e) Fluorescence integral intensity of 475nm and 538nm emission peaks is dependent on Er 3+ A trend graph of doping concentration; (f) is a chromaticity diagram of different samples; (g) Is a core-shell structure NaYF under 980nm excitation 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ A graph of the up-conversion emission intensity versus laser power; (h) Is 980nm laser excited core-shell structure NaYF 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ Nanoparticle up-conversion emission schematic; (i) is an energy transfer mechanism schematic;
FIG. 5 (a) is a bare core structure NaYF 4 :Yb 3+ /Tm 3+ (18/0.5 mol%) and core-shell NaYF 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) nanoparticles were emitted at 475nmUp-converting a fluorescence decay curve at the emission wavelength; (c) Is a bare core structure NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) and core-shell NaYF 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) nanoparticles up-convert fluorescence decay curves at 538nm emission wavelength; (b) Is of a core-shell structure NaYF 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/xmol%) (x=0.3/0.5/0.7%) nanoparticle up-conversion fluorescence decay curve at 475nm emission wavelength; (d) Is of a core-shell structure NaYF 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/xmol%) (x=0.3/0.5/0.7%) nanoparticle up-conversion fluorescence decay curve at 538nm emission wavelength;
FIG. 6 (a) is a core-shell NaYF 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) fluorescence spectrum of the nanoparticle at different temperatures; (b) a change in fluorescence intensity with temperature between 646nm and 700 nm; (c) A linear fitting graph of fluorescence intensity ratio and reciprocal temperature; (d) Absolute sensitivity versus relative sensitivity curve for FIR thermometry (laser: 980nm, power density: 4W/cm) -2 ) The method comprises the steps of carrying out a first treatment on the surface of the (e) cycle repeatability from 295K to 495K for FIR;
FIG. 7 (a) is a core-shell NaYF 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) linear fit plot of fluorescence intensity ratio versus reciprocal temperature for nanoparticles at 520nm to 538 nm; (b) Absolute sensitivity versus relative sensitivity curves for which 520nm and 538nm fluorescence intensity ratios are measured; (c) Is of a core-shell structure NaYF 4 :Yb 3 + /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) linear fit plot of fluorescence intensity ratio at 700nm to 800nm versus reciprocal temperature for nanoparticles; (d) An absolute sensitivity versus relative sensitivity curve for which the 700nm to 800nm fluorescence intensity ratio is measured;
FIG. 8 (a) is a bare core structure NaYF 4 :Yb 3+ /Tm 3+ (18/0.5 mol%) linear fit of fluorescence intensity ratio at 700nm to 646nm versus reciprocal temperature of nanoparticles; (b) Absolute sensitivity versus relative sensitivity curves for 700nm and 646nm fluorescence intensity ratio measurements; (c) Is a bare core structure NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) linear fit plot of fluorescence intensity ratio versus reciprocal temperature for nanoparticles at 520nm to 538 nm; (d) Absolute sensitivity versus relative sensitivity curves for 520nm and 538nm fluorescence intensity ratio measurements;
FIG. 9 (a) is an experimental arrangement of a fiber optic temperature sensing system; (b) Is the measured temperature and the standard temperature displayed on the heater (red line is the baseline at which the measured temperature is equal to the standard temperature); (c) is the FIR value recorded at different excitation powers at room temperature; (d) For FIR values recorded over 5 cycles between 295K and 495K.
Detailed Description
Various exemplary embodiments of the invention will now be described in detail, which should not be considered as limiting the invention, but rather as more detailed descriptions of certain aspects, features and embodiments of the invention.
It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In addition, for numerical ranges in this disclosure, it is understood that each intermediate value between the upper and lower limits of the ranges is also specifically disclosed. Every smaller range between any stated value or stated range, and any other stated value or intermediate value within the stated range, is also encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.
It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the invention described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from consideration of the specification of the present invention. The specification and examples are exemplary only.
As used herein, the terms "comprising," "including," "having," "containing," and the like are intended to be inclusive and mean an inclusion, but not limited to.
Example 1:
(1) Preparation of naked core Structure NaYF 4 :Yb 3+ /Tm 3+ (18/0.5 mol%) nanoparticles
YCl with the molar ratio of 81.5:18:0.5 is weighed according to the amount 3 ·6H 2 O、YbCl 3 ·6H 2 O and TmCl 3 ·6H 2 An aqueous solution (1 mL) of O with a total rare earth ion content of 0.5mmol was added to a 50mL flask, the water in the solution was evaporated under stirring with a magnetic stirrer, 3.75mL Oleic Acid (OA) and 7.5mL 1-Octadecene (ODE) were added after the water was completely evaporated, and the mixture was heated to 120℃under argon, and maintained for 30min to remove the water in the OA and ODE. Raising the temperature of the system to 160 ℃, and naturally cooling to room temperature after reacting for 60 min. 5mL of a solution containing 1.25 mmoles of NaOH and 2 mmoles of NH was added dropwise with vigorous stirring 4 F, and vigorously stirring at room temperature for 30min, then raising the system temperature to 100 ℃ under argon atmosphere, and removing the methanol solution from the reaction mixture. And finally, after the methanol is removed completely, rapidly heating to 300 ℃ under the protection of argon, keeping for 1.5h, and stopping heating after the reaction is finished. After the reaction system is naturally cooled to room temperature, precipitating the product with excessive absolute ethyl alcohol, washing the product for multiple times with a mixed solution of absolute ethyl alcohol and cyclohexane, and finally dispersing the reaction product in 4mL of cyclohexane to obtain the naYF with the naked core structure 4 :Yb 3+ /Tm 3+ (18/0.5 mol%) nanoparticles.
(2) Manufacturing processNaYF with core-shell structure 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/xmol%) (x= 0.3,0.5,0.7) nanoparticles
Will contain YCl 3 ·6H 2 O、YbCl 3 ·6H 2 O、ErCl 3 ·6H 2 Adding aqueous solutions (1 mL) with different proportions of O and total rare earth ion content of 0.5mmol into a 50mL flask, stirring and evaporating water in the solution under the action of a magnetic stirrer, adding 7.5mL of Oleic Acid (OA) and 15mL of 1-Octadecene (ODE) after the water is completely evaporated, heating the mixture to 120 ℃ under the protection of argon, and keeping the temperature for 30min to remove the water in the OA and the ODE. The temperature of the system was raised to 160℃and the reaction was continued for 60min until the solution became clear pale yellow, followed by natural cooling to room temperature. NaYF to be dispersed in 4mL of cyclohexane 4 :Yb 3+ /Tm 3+ And (3) dripping the bare core nano particles (the product prepared in the step (1)) into the reaction liquid. 5mL of a mixture containing 1.25 mmoles of NaOH and 2 mmoles of NH was added dropwise to the reaction flask with vigorous stirring 4 F, and stirring vigorously at room temperature for 30min, then raising the system temperature to 100 ℃ under the condition of introducing shielding gas argon, and removing methanol and cyclohexane solution in the reaction mixture. And finally, after the methanol and the cyclohexane are removed completely, rapidly heating to 300 ℃ under the protection of argon, keeping for 1.5h, and stopping heating after the reaction is finished. After the reaction system is naturally cooled to room temperature, precipitating the product with excessive absolute ethyl alcohol, washing the product with mixed solution of absolute ethyl alcohol and cyclohexane for multiple times, and finally vacuum drying the reaction product at 50 ℃ for 24 hours to obtain the oil-soluble core-shell NaYF 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/xmol%) (x= 0.3,0.5,0.7) nanoparticles.
(3) Preparation of shell NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) nanoparticles
YCl with the molar ratio of 81.5:18:0.5 is weighed according to the amount 3 ·6H 2 O、YbCl 3 ·6H 2 O and ErCl 3 ·6H 2 The total rare earth ion content of O is 0.5mA mol of aqueous solution (1 mL) was added to a 50mL flask, the water in the solution was evaporated under stirring with a magnetic stirrer, after the water had evaporated completely, 3.75mL Oleic Acid (OA) followed by 7.5mL 1-Octadecene (ODE) were added, and the mixture was heated to 120℃under argon protection for 30min to remove the water in OA and ODE. Raising the temperature of the system to 160 ℃, and naturally cooling to room temperature after reacting for 60 min. 5mL of a solution containing 1.25 mmoles of NaOH and 2 mmoles of NH was added dropwise with vigorous stirring 4 F, and vigorously stirring at room temperature for 30min, then raising the system temperature to 100 ℃ under the condition of introducing protective gas, and removing the methanol solution in the reaction mixture. And finally, after the methanol is removed completely, rapidly heating to 300 ℃ under the protection of argon, keeping for 1.5h, and stopping heating after the reaction is finished. After the reaction system is naturally cooled to room temperature, precipitating the product with excessive absolute ethyl alcohol, washing the product for multiple times with a mixed solution of absolute ethyl alcohol and cyclohexane, and finally dispersing the reaction product in 4mL of cyclohexane to obtain the shell-structured NaYF 4 :Yb 3+ /Er 3+ And (3) nanoparticles.
(4) Core-shell double-doped up-conversion nanoparticle material for improving sensitivity of non-contact temperature sensor and application method of core-shell double-doped up-conversion nanoparticle material
The core-shell double-doped up-conversion nanoparticle powder in the step 2 is adsorbed on the end face of the optical fiber and is used as a temperature sensing probe of the sensor. The excitation light of the 980nm laser propagates along the fiber to the wavelength division multiplexer. The excited nanoparticles produce up-converted fluorescence that will travel along the fiber through the wavelength division multiplexer and be received by the spectrometer analyzer for analysis. The fluorescence intensity was recorded by recording the up-conversion of the 700nm and 646nm emission peaks of the probe at real-time temperature changes of 295K to 495K. Establishing a temperature sensing relation, namely
The measured temperature is calculated and compared with a standard temperature to evaluate the feasibility of the application.
The performance of the nanoparticles prepared in example 1 was tested, and FIG. 1 (a) is a graph showing the bare core-structured and core-shell structured nanoparticles prepared in examples 1-2XRD pattern, (b) is an XRD locally enlarged pattern of the crystal face of the nanoparticle (201). As can be seen from the figure, the partitions are doped with different Tm 3+ And Er 3+ Content of core-shell NaYF 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ After the nanoparticle samples are dried, X-ray diffraction (XRD) characterization is carried out on the nanoparticle samples, and the diffraction positions of all the samples can be seen from a characterization chart to correspond to the diffraction peak positions in the JDGDS standard card NO. 28-1192. Zoning Tm doping in core shells 3+ And Er 3+ No impurity peak is generated. Nor destroy any original NaYF 4 This indicates that pure beta-phase NaYF is obtained 4 . To further demonstrate that the resulting samples were core-shell structured nanoparticles. As shown in fig. 1 (b), the XRD pattern corresponding to the (201) crystal plane is selected for local amplification, according to bragg equation, 2dsin θ=kλ, where d is the interplanar spacing, θ is the diffraction angle, k is a positive integer, and λ is the wavelength of X-ray. After coating the shell, the diffraction angle θ corresponding to the (201) crystal plane is shifted to a small angle, and k and λ are unchanged, so d value becomes large, which indicates that the crystal lattice expands. This is due to the fact that after coating the shell, the nanoparticles grow outwardly in the core layer, resulting in lattice expansion. Notably, the ion Er emits light with the shell layer 3+ The diffraction angle is continuously shifted towards a small angle as the content of Er increases, which indicates that 3+ Is increased in content of the nanoparticles, the crystal lattice of the nanoparticles expands further, thereby causing a luminescence center Tm 3+ And Er 3+ The symmetry of the nearby crystal field is damaged, the transition probability of the space forbidden resistances 4f-4f is improved, and the up-conversion luminescence is enhanced.
FIGS. 2 (a), (d) are bare core NaYF 4 :Yb 3+ /Tm 3+ (18/0.5 mol%) and core-shell NaYF 4 :Yb 3+ /Tm 3 + (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ As can be seen from the transmission electron microscope image of the (18/0.5 mol%) nanoparticle sample, the nanoparticles with a bare core structure or a core-shell structure are orderly arranged, no agglomeration phenomenon exists, and the morphology is similar to a hexagonal structure. The morphology and uniformity of other samples are similar. High heightThe resolved TEM image shows that the interplanar spacing between the bare core structure (b) and the core-shell structure (e) is 0.52nm, corresponding to NaYF 4 The (110) crystal face of the nano-particles shows that the synthesized nano-particles have good crystallinity, and the particle size and Zeta potential analyzer characterize NaYF 4 The particle size distribution of the nanoparticle sample is shown in the figures (c) and (f), and the hydration kinetic diameter d of the sample can be seen 1 ＝21.35±1.68nm，d 2 = 36.56 ±4.26nm, and the particle size was small. According to the Debye-scheler formula,
the particle size of the nanoparticle can be calculated from the half-width of the XRD strongest diffraction peak, where k=0.89 is Scherrer constant, λ= 0.154056nm is the wavelength of cukα rays, B M Is the half-width of the diffraction peak, and θ is the bragg angle corresponding to the maximum diffraction peak. The average crystal sizes were thus estimated to be 18-24nm and 33-42nm, respectively, further indicating agreement with the particle size measured by the particle size analyzer.
FIG. 3 is a TEM spectrum of the upconversion nanoparticle, and from the graph, the surface scanning distribution diagram of each doping element of F, Y, yb, tm, er is clearly seen, and the distribution of each element is uniform, which again shows that the core-shell structure NaYF is successfully synthesized 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) of upconverting nanoparticles.
It can be seen from FIGS. 4 (a), 4 (i) that the synthesized nanoparticles emit intense blue and green light, tm 3+ The emission peak of (C) is mainly concentrated near 475nm, corresponding to 1 G 4 → 3 H 6 Energy level transition; er (Er) 3+ The emission peak of (C) is mainly concentrated near 538nm, corresponding to 4 S 3/2 → 4 I 15/2 Energy level transitions. According to the luminous intensity (I UC ) And 980nm laser power density (P) NIR ) The relationship of (3) is known,
i.e. I UC And P NIR Is proportional to the power n, where n represents the absorption of 980nm near red by a photon emitted by the upconversion luminescence processPhoton number of external light. Tm (Tm) 3+ And Er 3+ The dependence of the fluorescence intensity of the radiative transitions on the power density is shown in fig. 4 (g), and as can be seen from the results of the linear fitting, 1 G 4 → 3 H 6 、 4 S 3/2 → 4 I 15/2 the energy level transition n values are 2.10 and 1.92, respectively, indicating that the energy level is Tm 3+ Three-photon absorption process and Er of (2) 3+ Two-photon absorption process of (a). In order to realize multiphoton up-conversion emission, the invention selects 18 percent Yb 3+ And 0.5% Tm 3+ The nano particles of the inner core are synthesized according to the proportion of the blue-green color (figure 4 c), and 18 percent of Yb is selected 3+ And 0.5% Er 3+ Is used for synthesizing the nano particles of the shell layer. As can be seen from FIG. 4 (b), the core-shell NaYF structure 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ Nanoparticle fluorescence intensity ratio bare core structure NaYF 4 :Yb 3+ /Tm 3+ About 7 times stronger, the shell layer overcomes the surface defect of the core nanoparticle after being coated with an active shell, so that the fluorescent intensity of the core-shell nanoparticle is stronger than that of the nanoparticle with a bare core structure. Also of note is NaYF 4 :Yb 3+ /Er 3+ As a shell layer of the core-shell structure, naYF with a bare core structure 4 :Yb 3+ /Er 3+ In contrast, there are also surface defects, but as can be seen from fig. 4 (b), the fluorescence intensity is about 4 times stronger than that of the bare core structure. This is due to the bare core structure NaYF 4 :Yb 3+ /Er 3+ Specific surface area of nanoparticle to shell NaYF 4 :Yb 3+ /Er 3+ The surface relative atomic number is increased, so that the surface atomic coordination is insufficient, unsaturated bonds and dangling bonds are increased, the surface effect can cause large surface energy and activity of the nano particles, further cause the surface electron transportation and structure change of the nano particles, and simultaneously cause the surface electron spin phenomenon and the electron energy spectrum change, thereby generating nonlinear optical effect, increasing non-radiative transition and reducing fluorescence intensity. This indicates a core-shell structure NaYF 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ Nanoparticles have tremendous potential in fluorescence imagingIs used for the application of the composition. Core-shell NaYF structure 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/xmol%) (x=0.3/0.5/0.7%) the fluorescence spectrum of the nanoparticle is shown in fig. 4 (d), and Tm can be seen in combination with fig. 4 (e) and 4 (h) 3+ Fluorescence intensity of 475nm of main emission peak of Er 3+ Is reduced by increasing the content of Er 3+ The main emission peak 538nm fluorescence intensity is along with Er 3+ Is increased by increasing the content of (2). This is due to the following Er 3+ The increase of the content promotes more electrons to be distributed in the two-photon transition 4 S 3/2 Energy level, thereby greatly increasing 4 S 3/2 → 4 I 15/2 Radiation transition such that Er 3+ And the main emission peak 538nm fluorescence is enhanced. In contrast, when the shell sensitizer ion Yb 3+ After absorbing 980nm excitation light, most of the excitation light is transmitted to shell luminescent ions Er through energy transfer 3+ Thereby reducing Yb from the shell layer 3+ To nuclear layer Yb 3+ Energy transfer process leading to nuclear layer luminescent ions Tm 3+ Receipt of sensitizer Yb 3+ The energy of the ions is continuously reduced such that Tm 3+ The fluorescence intensity of 475nm, which is the main emission peak of (C), becomes weak. As can be seen from FIG. 4 (f), when Er 3+ At a doping concentration of 0.3mol%, the sample emits blue light; when Er 3+ At a doping concentration of 0.7mol%, the sample emits green light; however, when Er 3+ At a doping concentration of 0.5mol%, the luminescence color of the sample is between blue and green light, and the fluorescence intensity is relatively strong. Therefore, the invention selects Er 3+ The sample with a doping concentration of 0.5mol% was further investigated for its temperature sensing properties.
As can be seen from fig. 5 (a) and (c), the core-shell nanoparticles each have a longer fluorescence lifetime than the bare core nanoparticles. Furthermore, as can be seen from FIG. 5 (b), as Er 3+ When the doping concentration is increased from 0.3mol% to 0.7mol%, the luminescence center Tm 3+ In (a) 1 G 4 The lifetime of the energy level gradually decreases, reaching 0.68ms at 0.5mol%, however, as can be seen from FIG. 5 (d), the luminescence center Er 3+ In (a) 4 S 3/2 The lifetime of the energy level increases gradually, reaching 0.30ms at 0.5 mol%. According to the fluorescence lifetime formula,
wherein k is F A decay constant, Σk, representing the fluorescence emission rate i Representing the decay constants of the various radiation processes. For the 475nm blue emission peak, due to the Er-dependent peak 3+ An increase in the doping amount, the luminescence center Tm 3+ The probability of a radiative transition is reduced such that the probability of a non-radiative transition is increased, thereby resulting in Σk i And the fluorescence lifetime is reduced. While the opposite is true for the 538nm green emission peak, resulting in an increase in fluorescence lifetime. Therefore, the invention selects the core-shell structure NaYF with moderate fluorescence life of 475nm and 538nm both of blue-green emission peaks 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) nanoparticles were studied further.
Table 1 shows the sensitivity comparisons of the different samples, and table 2 shows the provenance of each material.
TABLE 1 sensitivity comparison of different samples
Table 2 items 1-9 material provenance
| Project | Provenance of |
| 1 | Inventive example 1 |
| 2 | Chem.Phys.Lett.,2016, |
| 3 | PhysicalChemistryChemicalPhysicsPccp,2014,16,22665-22676 |
| 4 | RSCAdvances,2016,55307-55311 |
| 5 | Opt.Mater.,2016 |
| 6 | OPTICALMATERIALS-AMSTERDAM-,2017 |
| 7 | Opt.Mater.,2016,58,449-453 |
| 8 | RSCAdvances,2014,4,6391-6396 |
| 9 | Ceram.Soc.,2015,98,2595-2600 |
The FIR temperature measurement technology needs to meet two conditions, namely that the fluorescence intensity of radiation transition is large enough to avoid the influence of optical noise on temperature measurement; the second is that the change trend of fluorescence intensity of two energy levels downward transition is opposite, and the energy level difference between them is about 200cm -1 -2000cm -1 Between them. As is clear from fig. 6 (a) and 6 (b), the 646nm emission peak fluorescence intensity gradually decreases and the 700nm fluorescence intensity gradually increases with increasing temperature. And by calculation, tm 3+ The energy level difference between the light-emitting center wavelength of 700nm and 646nm is 1255cm -1 Meets the requirements of thermal coupling energy level. This indicates a core-shell structure NaYF 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ Nanoparticles can be used for sensitive temperature measurement. According to the formula of fluorescence intensity ratio of electron transition radiation of two thermally coupled energy levels from high energy level to low energy level,
wherein FIR is fluorescence intensity ratio, delta E is energy corresponding to energy level difference, k is Boltzmann constant, and T is Kelvin temperature. A linear fit of the logarithm of the fluorescence intensity ratio between 700nm and 646nm to the reciprocal of the temperature gave a good result as shown in FIG. 6 (c). The synthesized nano particles are shown to have unique advantages in the aspect of temperature sensing. From the mathematical definition of sensitivity, +.>
S A For absolute sensitivity, S R For relative sensitivity, FIR is the fluorescence intensity ratio, ΔE is the energy corresponding to the energy level difference, k is the Boltzmann constant, and T is the Kelvin temperature. The fitted curve is shown in 6 (d), and it is known that in the temperature measuring range from 295K to 495K, the sample is excited by 980nm laser and applied to the absolute sensitivity curve and the relative sensitivity curve obtained by the FIR temperature measuring technology, the absolute sensitivity curve monotonically increases along with the temperature rise, and the relative sensitivity curve monotonically decreases along with the temperature rise. Core-shell NaYF structure 4 :Yb 3 + /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) nanoparticles 3 F 3 → 3 H 6 (700 nm) and 1 G 4 → 3 F 4 the maximum absolute sensitivity of the (646 nm) thermally coupled energy level pair reaches 0.0250K at 495K -1 Maximum relative sensitivity reaches 2.155% K at 295K -1 . FIG. 6 (e) shows that the FIR cycle repeatability is good and the FIR at each temperature point tends to be stable, indicating that it is sensitive in rising and falling temperaturesAnd (5) responding. On the one hand, as can be seen from Table 1, the material of the present invention is more based on Tm than the current society 3+ And Er 3+ The absolute sensitivity of the material is high; on the other hand, as shown in FIG. 7, different thermocouple energy levels are applied to temperature measurement, and the temperature measurement sensitivity is different, and it is worth mentioning that the ratio is that 2 H 11/2 → 4 I 15/2 (520 nm) and 4 S 3/2 → 4 I 15/2 the absolute sensitivity of the (538 nm) energy level pair is an order of magnitude higher than 3 F 3 → 3 H 6 (700 nm) and 3 H 4 → 3 H 6 the absolute sensitivity of the (800 nm) energy level pair is two orders of magnitude higher, further illustrates that the 700nm and 646nm thermal coupling energy level pair has more application advantages, and has great application prospect in temperature measurement in modern production and life.
As can be seen from the combination of FIG. 6 (c) with FIGS. 8 (a) and 8 (c), the core-shell NaYF structure 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ The linear fitting degree of the fluorescence intensity ratio and the temperature reciprocal of the nano particle is better than that of the bare core structure NaYF 4 :Yb 3+ /Tm 3+ And NaYF 4 :Yb 3+ /Er 3+ And (3) nanoparticles. And comparing fig. 6 (d) with fig. 8 (b) and 8 (d), it can be seen that the absolute sensitivity of the core-shell nanoparticle is better than that of the bare core nanoparticle. Referring to FIG. 4 (b), a core-shell NaYF structure 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ NaYF with nano particle ratio bare core structure 4 :Yb 3+ /Tm 3+ 、NaYF 4 :Yb 3+ /Er 3+ The fluorescent intensity of the nano particles is 7 times and about 4 times stronger, which indicates that the up-conversion fluorescence is enhanced, the absolute sensitivity of the sample is possibly improved, and indicates that the NaYF with the core-shell structure 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ Nanoparticles are more suitable for optical temperature sensing.
The invention aims to study the NaYF of the core-shell structure 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ Feasibility and reliability of application of nano particles in optical fiber temperature sensor are establishedA simple temperature measurement platform is shown in fig. 9 (a). The nanoparticle powder is adsorbed on the end face of the optical fiber and is used as a temperature sensing probe of the sensor. Excitation light comes from a 980nm laser and propagates along the fiber (yellow arrow) to a Wavelength Division Multiplexer (WDM). The excited nanoparticles produce up-converted fluorescence that will travel along an optical fiber (red arrow) through the WDM and be received by a spectrometer analyzer (OSA) for analysis. The feasibility of the sensor was assessed by recording the up-converted fluorescence intensity of the 700nm and 646nm emission peaks of the probe at real-time temperature changes of 295K to 495K. 9 (b) by the formula
Calculating the measured temperature (where T is Kelvin temperature, FIR is fluorescence intensity ratio,/-)>
Δe is the energy corresponding to the energy level difference and K is the boltzmann constant) and is mostly within 5K compared to the standard temperature, indicating that the sensor temperature measurement is reliable. Thermodynamic statistics indicate that the population distributed over the thermocouple energy levels satisfies the boltzmann distribution, which is temperature dependent and not low excitation power. Thus, the effect of excitation power on FIR is shown in FIG. 9 (c), and it is apparent that FIR is stable at low power excitation. To test the repeatability and recyclability of the platform materials, FIR was measured over several heating and cooling cycles of 295K and 495K, as shown in FIG. 9 (d), from which it can be seen that the numerical fluctuations were small. Therefore, the core-shell structure NaYF is adopted 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ As the nano particles are used as the optical fiber temperature sensor, the probe material is feasible, reliable and recyclable, and provides a good foundation for further application in the biomedical field and severe environment in the future.
As Er in example 1 3+ The following study was conducted based on a doping molar amount of 0.5%.
Example 2
As in example 1, naYF was prepared 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) of the nanoparticles in step (2), the temperature of the system is raised to 150 ℃, and the reaction is carried out for 60min and then the system is naturally cooled to room temperature. As a result of the test in the same manner as in example 1, it was found that the fluorescence intensity was decreased and the absolute sensitivity was also decreased by 0.0024K at 150 ℃ -1 。
Example 3
As in example 1, naYF was prepared 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ In the step (2) of (18/0.5 mol%) nano particles, the temperature of the system is raised to 160 ℃, and after 30min of reaction, the system is naturally cooled to room temperature. As a result of the test in the same manner as in example 1, it was found that the fluorescence intensity was decreased and the absolute sensitivity was also decreased by 0.0020K at a temperature of 30min -1 。
Example 4
As in example 1, naYF was prepared 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) nanoparticles in step (2), after methanol and cyclohexane were purged, the temperature was rapidly raised to 290 ℃ under argon protection and maintained for 1.5h. As a result of the test in the same manner as in example 1, it was found that the fluorescence intensity was decreased and the absolute sensitivity was also decreased by 0.0028K at 290 ℃ -1 。
Example 5
As in example 1, naYF was prepared 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) nanoparticles in step (2), after methanol and cyclohexane were purged, the temperature was rapidly raised to 300 ℃ under argon protection and maintained for 1h. As a result of the test in the same manner as in example 1, it was found that the fluorescence intensity was decreased and the absolute sensitivity was also decreased by 0.0032K when the temperature was maintained for 1 hour -1 。
Comparative example 1
As in example 1, naYF was prepared 4 :Yb 3+ /Tm 3+ (18/0.5mol％)@NaYF 4 :Yb 3+ /Er 3+ (18/0.5 mol%) nanoparticles in step (2), 5mL of a solution containing 1.25 mmole of NaOH and 2 mmole of NH was added dropwise to the reaction flask 4 After the methanol solution of F is directly heated to 100 ℃ under the condition of introducing protective gas and argon, the system is not stirred for 30min before the temperature is increased, the test method is the same as that of example 1, and the absolute sensitivity is reduced by 0.0018K -1 。
The foregoing description of the preferred embodiments of the invention is not intended to limit the invention to the particular embodiments disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.
Claims (4)
1. Core-shell structure NaYF 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ Application of nano particles as probes for improving sensitivity of a non-contact temperature sensor; in the core-shell structure NaYF 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ In the nano-particle, the Er 3+ The doping mole amount of the catalyst is 0.3-0.7%;
NaYF of the core-shell structure 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ The preparation method of the nanoparticle comprises the following steps:
(1) By mixing lanthanide rare earth ions Ln 3+ Magnetically stirring the aqueous solution, adding oleic acid and octadecene, heating to 120 ℃ under the protection of argon gas for 30min, then raising the temperature to 150-160 ℃ for 60min, and cooling to room temperature; the Ln 3+ Is Y 3+ ，Yb 3+ And Tm 3+ The method comprises the steps of carrying out a first treatment on the surface of the The Y is 3+ ，Yb 3+ And Tm 3+ The molar ratio of (2) is 81.5:18:0.5;
(2) Adding NaOH and NH into the solution obtained in the step (1) 4 F, stirring the methanol solution, heating to 100-120 ℃ under the protection of argon, heating to 280-310 ℃ after the methanol is removed completely, keeping the temperature for 1-2h, and cooling to room temperature to obtain nano particles A;
(3) Washing the obtained nanoparticle A, and dissolving in cyclohexaneIn alkane, the naked core structure NaYF is obtained 4 :Yb 3+ /Tm 3+ A nanoparticle;
(4) By mixing lanthanide rare earth ions Ln 3+ Magnetically stirring the aqueous solution, adding oleic acid and octadecene, heating to 120 ℃ under the protection of argon gas for 30min, then raising the temperature to 150-160 ℃ for 60min, and cooling to room temperature; the Ln 3+ Is Y 3+ ，Yb 3+ And Er 3+ The method comprises the steps of carrying out a first treatment on the surface of the The Y is 3+ ，Yb 3+ And Er 3+ The molar ratio of (1.3-81.7) is 18 (0.3-0.7);
(5) Will contain NaOH and NH 4 Methanol solution of F and bare nuclear structure NaYF dispersed in cyclohexane in step (3) 4 :Yb 3+ /Tm 3+ Adding the nano particles into the solution obtained in the step (4), stirring, heating to 100-120 ℃ under the protection of argon, raising the temperature to 280-310 ℃ after methanol and cyclohexane are removed completely, keeping for 1-2h, and cooling to room temperature to obtain nano particles B;
(6) Washing the obtained nano particles B, and then vacuum drying for 24 hours to obtain the core-shell NaYF 4 :Yb 3+ /Tm 3+ @NaYF 4 :Yb 3+ /Er 3+ And (3) nanoparticles.
2. The use according to claim 1, wherein step (1) said Y 3+ ，Yb 3+ And Tm 3+ Respectively selected from YCl 3 ·6H 2 O、YbCl 3 ·6H 2 O and TmCl 3 ·6H 2 O; step (4) the Y 3+ ，Yb 3+ And Er 3+ Is respectively selected from YCl 3 ·6H 2 O、YbCl 3 ·6H 2 O and ErCl 3 ·6H 2 O。
3. The use according to claim 1, wherein the volume ratio of oleic acid to octadecene in step (1) is (3.5-4): 7-8; the volume ratio of the oleic acid to the octadecene in the step (4) is (7-8) to (14-16).
4. The use according to claim 1, characterized in thatIn step (2), the Y 3+ With NaOH and NH 4 The molar ratio of F is 1 (3.0-3.1) (4.9-5.0); step (5) the Y 3+ With NaOH and NH 4 The molar ratio of F is 1 (3.0-3.1) to 4.9-5.0.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111559055.2A CN114214069B (en) | 2021-12-20 | 2021-12-20 | Core-shell double-doped nanoparticle material for improving sensitivity of non-contact temperature sensor and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111559055.2A CN114214069B (en) | 2021-12-20 | 2021-12-20 | Core-shell double-doped nanoparticle material for improving sensitivity of non-contact temperature sensor and preparation method and application thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114214069A CN114214069A (en) | 2022-03-22 |
| CN114214069B true CN114214069B (en) | 2023-05-12 |
Family
ID=80704089
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111559055.2A Active CN114214069B (en) | 2021-12-20 | 2021-12-20 | Core-shell double-doped nanoparticle material for improving sensitivity of non-contact temperature sensor and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114214069B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114656966B (en) * | 2022-04-15 | 2023-07-25 | 中国科学院福建物质结构研究所 | Four-layer core-shell structure nano material and preparation method and application thereof |
| CN115595140A (en) * | 2022-09-30 | 2023-01-13 | 安徽师范大学（Cn） | Preparation method of DHCA (dehydroepiandrosterone) -modified upconversion luminescent nano material and method for detecting solution and cell temperature by using DHCA-modified upconversion luminescent nano material |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104371726B (en) * | 2014-11-26 | 2016-08-17 | 中国计量学院 | It is nanocrystalline and its preparation method and application that a kind of high temperature that can be used for temperature sensing strengthens up-conversion fluorescence type |
| CN112111275B (en) * | 2020-08-26 | 2022-01-14 | 复旦大学 | Temperature measurement method based on rare earth luminescent life temperature probe |
-
2021
- 2021-12-20 CN CN202111559055.2A patent/CN114214069B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN114214069A (en) | 2022-03-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Sehrawat et al. | Combustion derived color tunable Sm3+ activated BaLaAlO4 nanocrystals for various innovative solid state illuminants | |
| CN114214069B (en) | Core-shell double-doped nanoparticle material for improving sensitivity of non-contact temperature sensor and preparation method and application thereof | |
| Chen et al. | Core@ shell upconverting nanoarchitectures for luminescent sensing of temperature | |
| Kolesnikov et al. | Eu3+ concentration effect on luminescence properties of YAG: Eu3+ nanoparticles | |
| Kolesnikov et al. | Construction of efficient dual activating ratiometric YVO 4: Nd 3+/Eu 3+ nanothermometers using co-doped and mixed phosphors | |
| Sun et al. | Concentration-regulated photon upconversion and quenching in NaYF 4: Yb 3+, Er 3+ nanocrystals: nonexponentiality revisited | |
| Grzyb et al. | Synthesis, spectroscopic and structural studies on YOF, LaOF and GdOF nanocrystals doped with Eu3+, synthesized via stearic acid method | |
| CN108285786B (en) | Fluorescent temperature probe material | |
| Liu et al. | Power dependence of upconversion luminescence of Er3+ doped Yttria nanocrystals and their bulk counterpart | |
| Li et al. | A wide range photoluminescence intensity-based temperature sensor developed with BN quantum dots and the photoluminescence mechanism | |
| Yu et al. | Doping concentration of Eu3+ as a fluorescence probe for phase transformation of zirconia | |
| Meng et al. | Preparation of core–shell structured NaYF 4: Yb 3+/Tm 3+@ NaYF 4: Yb 3+/Er 3+ nanoparticles with high sensitivity, low resolution and good reliability and application of their fluorescence temperature properties | |
| Du et al. | A broad-range temperature sensor dependent on the magnetic and optical properties of SrF 2: Yb 3+, Ho 3+ | |
| Dwivedi et al. | Ho3+ activated Ca0. 5Y1. 90-xO3 green-emitting nanophosphors for solid state lightening: Synthesis, characterization and photoluminescence properties | |
| Sha et al. | Pre-assessments of optical transition, gain performance and temperature sensing of Er3+ in NaLn (MoO4) 2 (Ln= Y, La, Gd and Lu) single crystals by using their powder-formed samples derived from traditional solid state reaction | |
| Trejgis et al. | Effect of the nanoparticle size on thermometric properties of a single-band ratiometric luminescent thermometer in NaYF 4: Nd 3+ | |
| Yu et al. | Effects of K+ and Gd3+ concentration on up-conversion luminescence and optical thermometric properties in NaYF4: Yb/Ho microcrystals | |
| Gao et al. | Synthesis of Yb 3+, Ho 3+ and Tm 3+ co-doped β-NaYF 4 nanoparticles by sol–gel method and the multi-color upconversion luminescence properties | |
| Dehkordi et al. | The blue-green emission color of Ag+, Gd3+ co-activated CdWO4 phosphor via energy transfer for luminescence applications | |
| Liu et al. | Efficient two-color luminescence of Er3+/Yb3+/Li+: ZrO2 nanocrystals | |
| Hernández-Álvarez et al. | Multifunctional optical sensing platform of temperature, pressure (vacuum) and laser power density: NaYF 4: Gd 3+, Yb 3+, Er 3+ nanomaterial as luminescent thermometer, manometer and power meter | |
| Archana et al. | Influence of rare earth substitution on structure, photoluminescence emission properties and Judd-Ofelt analysis of ZnS: Eu3+ red phosphors | |
| Zhao et al. | Photoluminescence characteristics of CaSrSiO4: Yb3+, Er3+, Ag phosphor and its application on optical temperature sensor | |
| Liu et al. | Synthesis and spectroscopic properties of Er3+/Yb3+-codoped GdNbO4 phosphor for thermometry and marine safety protection | |
| Meng et al. | Retracted Article: Effect of Ca 2+ doping on the upconversion luminescence properties of NaYF 4: Yb 3+/Tm 3+ nanoparticles and study of its temperature measurement performance |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| EE01 | Entry into force of recordation of patent licensing contract |
Application publication date: 20220322 Assignee: Guilin Fuankang Medical Products Co.,Ltd. Assignor: GUILIN University OF TECHNOLOGY Contract record no.: X2023980045093 Denomination of invention: A core-shell double doped nanoparticle material for improving the sensitivity of non-contact temperature sensors and its preparation method and application Granted publication date: 20230512 License type: Common License Record date: 20231030 |
|
| EE01 | Entry into force of recordation of patent licensing contract |