Up-conversion luminescent transparent ceramic material as well as preparation method and application thereof
By coating a layered rare earth hydroxide doped with rare earth ions onto an alumina ceramic substrate and then calcining it, the problems of long preparation time and high equipment requirements for transparent ceramic materials have been solved. This has enabled the efficient preparation of upconversion luminescent ceramic materials with good light transmittance and thermal stability, which can be applied to lasers, temperature sensors, and lighting.
Patent Information
- Application Number
- CN202410581067.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-11
- Publication Date
- 2025-11-11
AI Technical Summary
Existing methods for preparing transparent ceramic materials are time-consuming, require sophisticated equipment, and have poor thermal properties of phosphors, which affect optical performance.
Upconversion luminescent transparent ceramic materials are prepared by coating layered rare earth hydroxides doped with rare earth ions onto an alumina ceramic substrate and then carrying out an interfacial reaction through calcination.
The preparation process shortens the time and reduces equipment requirements. The resulting transparent ceramic material has good light transmittance and thermal stability, making it suitable for lasers, temperature sensors, and lighting.
Smart Images
Figure CN120923262A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of upconversion luminescent materials technology, specifically to an upconversion luminescent transparent ceramic material, its preparation method, and its application. Background Technology
[0002] Among garnet compounds, yttrium aluminum garnet (YAG) has been widely studied due to its stable chemistry, high melting point, and ease of doping with other rare earth ions, and is commonly used in solid-state lasers and LEDs. In recent years, researchers have discovered that gadolinium aluminum garnet (GdAG) has extremely high application potential in optics, which has attracted significant attention from researchers. Currently, most luminescent materials are used in devices in the form of phosphors; however, phosphors have poor thermal properties, and when used with encapsulating resins, differences in refractive index can also affect fluorescence performance.
[0003] In addition, transparent ceramic materials are usually prepared by high-temperature solid-state method, gel combustion method or co-precipitation method, but these methods have the problems of long time and high equipment requirements. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to provide an upconversion luminescent transparent ceramic material and its preparation method. The obtained upconversion luminescent transparent ceramic material has good light transmittance and thermal stability, which can not only ensure optical uniformity, but also easily make into various complex shapes.
[0005] The technical problem to be solved by this invention is achieved by the following technical solution:
[0006] The first objective of this invention is to provide a method for preparing an upconversion luminescent transparent ceramic material, wherein a layered rare earth hydroxide doped with rare earth ions is coated on an alumina ceramic substrate, and an interfacial reaction is carried out by calcination to obtain the upconversion luminescent transparent ceramic material.
[0007] The second objective of this invention is to provide an upconversion luminescent transparent ceramic material obtained by the aforementioned preparation method.
[0008] A third objective of this invention is to provide the application of the aforementioned upconversion luminescent transparent ceramic material in lasers, temperature sensors, and lighting.
[0009] The beneficial effects of this invention are as follows: This invention coats layered rare earth hydroxides doped with rare earth ions onto an alumina ceramic substrate and prepares a luminescent transparent ceramic material through interfacial reaction by calcination; this preparation method not only reduces the time consumption but also lowers the requirements for equipment; the obtained transparent ceramic luminescent material is non-toxic and harmless to the human body and has advantages such as good mechanical strength and wear resistance, and can be applied in fields such as lasers, temperature sensors, and lighting. Attached Figure Description
[0010] Figure 1 This is a schematic diagram of the preparation process of the transparent ceramic materials in Example 1 and Comparative Examples 1-4;
[0011] Figure 2 A is a SEM image of the LGdH:Yb,Er precursor obtained in Example 1; Figure 2 B is a SEM image of the transparent ceramic material obtained in Example 1; Figure 2 C is from Figure 2 A portion extracted from B; Figure 2 DG for Figure 2 The EDS elemental analysis spectrum of the portion extracted from C;
[0012] Figure 3 A is the upconversion luminescence spectrum of the transparent ceramic material obtained in Example 1 under irradiation with a 980nm excitation light source; Figure 3 B are the XRD patterns of the LGdH:Yb,Er precursor (a) and transparent ceramic material (b) obtained in Example 1, respectively. Figure 3 C is the thermogravimetric analysis diagram of the LGdH:Yb,Er precursor obtained in Example 1; Figure 3 D is the FT-IR spectrum of the LGdH:Yb,Er precursor obtained in Example 1;
[0013] Figure 4 XRD patterns of the transparent ceramic materials obtained in Example 1 and Comparative Examples 1-4;
[0014] Figure 5 The images show the upconversion luminescence spectra of the transparent ceramic materials obtained in Example 1 and Comparative Examples 1-4 under irradiation with a 980 nm excitation light source. Detailed Implementation
[0015] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific embodiments and illustrations.
[0016] This invention provides a method for preparing an upconversion luminescent transparent ceramic material, wherein a layered rare earth hydroxide doped with rare earth ions is coated on an alumina ceramic substrate, and an interfacial reaction is carried out by calcination to obtain the upconversion luminescent transparent ceramic material.
[0017] In a further technical solution, the layered rare earth hydroxide includes, but is not limited to, one or more of layered gadolinium (Gd) hydroxide, layered yttrium (Y) hydroxide, and layered lutetium (Lu) hydroxide. Preferably, the layered rare earth hydroxide is layered gadolinium (Gd) hydroxide. This invention prepares GdAG by reacting rare earth ion-doped layered gadolinium hydroxide with an alumina ceramic substrate.
[0018] In a further technical solution, the rare earth ions include, but are not limited to, one or more of the following ions: holmium (Ho), europium (Eu), neodymium (Nd), erbium (Er), ytterbium (Yb), cerium (Ce), terbium (Tb), and dysprosium (Dy).
[0019] In a further technical solution, the calcination temperature is not lower than 1500℃, and the time is 1.5-2.5 hours. GdAG cannot be prepared under calcination temperatures below 1500℃.
[0020] In a further technical solution, the layered rare earth hydroxide doped with rare earth ions is obtained by a hydrothermal reaction of a water-soluble salt of a rare earth metal with an alkali. The hydrothermal reaction uses water as the reaction solvent, is environmentally friendly, and has a fast reaction rate, enabling the successful preparation of layered rare earth hydroxide doped with rare earth ions.
[0021] Preferably, the water-soluble salt is one or more selected from nitrates, sulfates, chlorides, and acetates. A water-soluble salt of a rare earth metal is used as the reaction raw material, dissolving in water to form a homogeneous solution.
[0022] Preferably, the alkali is NH3·H2O. Alternatively, other types of alkalis known in the art can be used to prepare layered rare earth hydroxides doped with rare earth ions via a hydrothermal reaction with water-soluble salts of rare earth metals.
[0023] Preferably, the hydrothermal reaction is carried out at a temperature of 110-130°C for 8-16 hours. It is necessary to control the temperature and time of the hydrothermal reaction to reduce energy consumption while obtaining the target product.
[0024] This invention provides an upconversion luminescent transparent ceramic material obtained by the aforementioned preparation method.
[0025] This invention provides the application of the aforementioned upconversion luminescent transparent ceramic material in lasers, temperature sensors, and lighting.
[0026] The following examples are implemented using Er 3+ and Yb 3+ Double-doped GdAG is used to enhance the luminescence intensity of the activated ions. Yb 3+ As a sensitizing ion, its energy level transition is related to Er 3+ The energy matching of the ff transition, when irradiated by a 980nm laser, Yb 3+ Transfer the absorbed energy to Er 3+ Er 3+ As an activator, its excited state and ground state Gd 3+ The closer proximity of the energy levels facilitates energy transfer during the upconversion process, ultimately improving luminescence performance. Alternatively, other rare-earth ions can be used to replace Er.3+ and Yb 3+ Single-doped or double-doped GdAG will not be discussed further here.
[0027] Example 1
[0028] Preparation of LGdH:Yb,Er precursor: Ln(NO3)3·6H2O (Ln being Gd, Er, and Yb with a molar ratio of Gd, Yb, and Er of 83:15:2) was placed in a beaker, and deionized water was added and mixed thoroughly. Then, 25% NH3·H2O was added dropwise to the solution. The addition was stopped when the pH of the solution reached 8, and the mixture was stirred continuously for 10 min. The resulting mixture was transferred to a reaction vessel and heated in a 120℃ oven for 12 h. After the reaction vessel cooled to room temperature, the product was separated by filtration, washed twice with deionized water, dried in a 60℃ oven for 2 h, cooled, and then ground to obtain the LGdH:Yb,Er precursor.
[0029] Preparation of transparent ceramic material: The above-mentioned LGdH:Yb,Er precursor was spin-coated on an alumina ceramic substrate and then calcined at 1500℃ for 2h to obtain transparent ceramic material.
[0030] Figure 2 A is a SEM image of the LGdH:Yb,Er precursor obtained in Example 1. From Figure 2 As can be seen from A, the precursor is a hexagonal nanosheet with an average size of 10 μm.
[0031] Figure 2 B is a SEM image of the transparent ceramic material obtained in Example 1. From... Figure 2 As can be seen from B, the nanosheet-like precursor has been completely transformed into a clustered compound composed of dense and irregular blocky materials bonded together.
[0032] Figure 2 C is from Figure 2 A portion extracted from B. Figure 2 DG for Figure 2 The EDS elemental analysis spectrum of the portion extracted from C. From Figure 2 As can be seen from DG, the transparent ceramic material obtained in Example 1 contains Al, Er, Yb and Gd elements, and the element content is relatively high.
[0033] Figure 3 A is the upconversion luminescence spectrum of the transparent ceramic material obtained in Example 1 under irradiation with a 980nm excitation light source. From Figure 3 As can be seen from A, the spectrum of this transparent ceramic material contains three peaks: two green emission peaks located at 510-535 nm and 535-560 nm, and a red emission peak located at 640-680 nm. These emission peaks are due to Er3+ This is caused by the absorption of energy upon stimulation, resulting in electron-electron transitions. The green light emission region can be attributed to Er. 3+ Ionic 2 H 11 / 2 → 4 I 15 / 2 and 4 S 3 / 2 → 4 I 15 / 2 The jump, the red light emission region can be attributed to Er 3+ of 4 F 9 / 2 → 4 I 15 / 2 Leap forward.
[0034] Figure 3 B shows the XRD patterns of the LGdH:Yb,Er precursor (b) and the transparent ceramic material (a) obtained in Example 1. Figure 3 B shows that Gd3Al5O 12 The peak shifts to the right, corresponding to Gd3Al5O 12 The standard card matches, indicating that Al2O3 participated in the interfacial reaction. Example 1 successfully prepared GdAG:Yb,Er transparent ceramic material.
[0035] Figure 3 C is the thermogravimetric analysis diagram of the LGdH:Yb,Er precursor obtained in Example 1. From Figure 3 As can be seen from C, four weight loss stages occurred between 20-800℃, with a total mass loss of 28.55%. The first stage occurred at 70℃, during which the mass of adsorbed water on the surface of the nanoparticles was lost. The second stage occurred between 70-210℃, during which the mass of bound water between the layered nanomaterials was lost, accounting for 8% of the total mass. From this, it can be calculated that LGdH:Yb,Er contains 1.5 mol of bound water. The third stage occurred between 210-370℃, during which the mass of the hydroxyl groups of the layered rare earth hydroxide was lost. The final stage occurred after 370℃, during which the layered rare earth hydroxide decomposed to form Gd₂O₃. Therefore, the chemical formula of the layered rare earth hydroxide can be deduced to be Gd₂(OH)₅·NO₃·1.5H₂O.
[0036] Figure 3 D is the FT-IR spectrum of the LGdH:Yb,Er precursor obtained in Example 1. Figure 3 D shows that 3500-3750cm -1 The absorption peak originates from the hydroxyl group (OH). - The vibration, 3000-3500cm -1 absorption peak and 1600 cm⁻¹ -1The absorption peaks are all due to the stretching vibrations of OH and HOH in water, [50, 51], respectively. These vibrations prove the presence of water molecules; 1358 cm⁻¹ -1 The absorption peak is due to NO 3- The bending vibration.
[0037] Comparative Example 1
[0038] The preparation method of LGdH:Yb,Er precursor and transparent ceramic material is the same as in Example 1, except that the calcination temperature is adjusted to 800℃.
[0039] Comparative Example 2
[0040] The preparation method of LGdH:Yb,Er precursor and transparent ceramic material is the same as in Example 1, except that the calcination temperature is adjusted to 1000℃.
[0041] Comparative Example 3
[0042] The preparation method of LGdH:Yb,Er precursor and transparent ceramic material is the same as in Example 1, except that the calcination temperature is adjusted to 1200℃.
[0043] Comparative Example 4
[0044] The preparation method of LGdH:Yb,Er precursor and transparent ceramic material is the same as in Example 1, except that the calcination temperature is adjusted to 1300℃.
[0045] Figure 4 XRD patterns of the transparent ceramic materials obtained in Example 1 and Comparative Examples 1-4. Figure 4 It can be seen that when LGdH and Al2O3 are calcined at 800℃, only (Gd) is present in the product. 41.5 :Er 7.5 The presence of (Yb)₂O₃ indicates that Al₂O₃ did not participate in the reaction at 800℃; when the calcination temperature is 1000℃, the main component of the product is (Gd)₂O₃. 41.5 :Er 7.5 Yb)2O3, with a small amount of (Gd) 41.5 :Er 7.5 Yb)4Al2O9 exists; when the calcination temperature reaches 1200℃, the main component of the product is (Gd) 41.5 :Er 7.5 :Yb)AlO3, and a small amount of (Gd) 41.5 :Er 7.5 :Yb)3Al5O 12 When the calcination temperature reaches 1300℃, the main component of the product is (Gd). 41.5 :Er 7.5 :Yb)AlO3, and a small amount of (Gd) exists.41.5 :Er 7.5 :Yb)3Al5O 12 When the calcination temperature reaches 1500℃, only (Gd) 41.5 :Er 7.5 :Yb)3Al5O 12 Therefore, only by calcining LGdH with Al2O3 at 1500℃ can GdAG:Yb,Er transparent ceramic materials be obtained.
[0046] Figure 5 The images show the upconversion luminescence spectra of the transparent ceramic materials obtained in Example 1 and Comparative Examples 1-4 under 980 nm excitation light source irradiation. Figure 5 It can be seen that when the calcination temperature is below 1000℃, the intensity of red light is much higher than that of green light, so green light is not displayed. When the calcination temperature is above 1200℃, it can be observed that the shape and position of the emission peak do not change with the increase of temperature, but the overall intensity of the peak increases. When the calcination temperature is above 1300℃, the intensity of green light is higher than that of red light. When the calcination temperature is 1500℃, the intensity of green light is significantly higher than that of red light. This indicates that Example 1 successfully prepared a transparent GdAG:Yb,Er ceramic material.
[0047] Example 2
[0048] Preparation of LGdH:Yb,Er precursor: Ln(NO3)3·6H2O (Ln being Gd, Er, and Yb with a molar ratio of Gd, Yb, and Er of 83:15:2) was placed in a beaker, and deionized water was added and mixed thoroughly. Then, 25% NH3·H2O was added dropwise to the solution. The addition was stopped when the pH of the solution reached 8, and the mixture was stirred continuously for 10 min. The resulting mixture was transferred to a reaction vessel and heated in a 130℃ oven for 10 h. After the reaction vessel cooled to room temperature, the product was separated by filtration, washed twice with deionized water, dried in a 60℃ oven for 2 h, cooled, and then ground to obtain the LGdH:Yb,Er precursor.
[0049] Preparation of transparent ceramic material: The above-mentioned LGdH:Yb,Er precursor was spin-coated on an alumina ceramic substrate and then calcined at 1500℃ for 2h to obtain transparent ceramic material.
[0050] Example 3
[0051] Preparation of LGdH:Yb,Er precursor: Ln(NO3)3·6H2O (Ln being Gd, Er, and Yb with a molar ratio of Gd, Yb, and Er of 83:15:2) was placed in a beaker, and deionized water was added and mixed thoroughly. Then, 25% NH3·H2O was added dropwise to the solution. The addition was stopped when the pH of the solution reached 8, and the mixture was stirred continuously for 10 min. The resulting mixture was transferred to a reaction vessel and heated in a 120℃ oven for 12 h. After the reaction vessel cooled to room temperature, the product was separated by filtration, washed twice with deionized water, dried in a 60℃ oven for 2 h, cooled, and then ground to obtain the LGdH:Yb,Er precursor.
[0052] Preparation of transparent ceramic material: The above-mentioned LGdH:Yb,Er precursor was spin-coated on an alumina ceramic substrate and then calcined at 1500℃ for 3h to obtain transparent ceramic material.
[0053] Example 4
[0054] Preparation of LGdH:Yb,Er precursor: Ln(NO3)3·6H2O (Ln being Gd, Er, and Yb with a molar ratio of Gd, Yb, and Er of 83:15:2) was placed in a beaker, and deionized water was added and mixed thoroughly. Then, 25% NH3·H2O was added dropwise to the solution. The addition was stopped when the pH of the solution reached 8, and the mixture was stirred continuously for 10 min. The resulting mixture was transferred to a reaction vessel and heated in a 120℃ oven for 12 h. After the reaction vessel cooled to room temperature, the product was separated by filtration, washed twice with deionized water, dried in a 60℃ oven for 2 h, cooled, and then ground to obtain the LGdH:Yb,Er precursor.
[0055] Preparation of transparent ceramic material: The above-mentioned LGdH:Yb,Er precursor was spin-coated on an alumina ceramic substrate and then calcined at 1600℃ for 2h to obtain transparent ceramic material.
[0056] The transparent GdAG:Yb,Er ceramic materials can also be prepared using the above Examples 2-4.
[0057] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.
Claims
1. A method for preparing an upconversion luminescent transparent ceramic material, characterized in that: A layered rare earth hydroxide doped with rare earth ions was coated onto an alumina ceramic substrate, and an interfacial reaction was carried out by calcination to obtain an upconversion luminescent transparent ceramic material.
2. The preparation method according to claim 1, characterized in that: The layered rare earth hydroxide is one or more of layered gadolinium hydroxide, layered yttrium hydroxide, and layered lutetium hydroxide.
3. The preparation method according to claim 1, characterized in that: The rare earth ions are one or more of the following: holmium, europium, neodymium, erbium, ytterbium, cerium, terbium, and dysprosium.
4. The preparation method according to claim 1, characterized in that: The calcination temperature is not lower than 1500℃, and the time is 1.5-2.5h.
5. The preparation method according to claim 1, characterized in that: The layered rare earth hydroxides doped with rare earth ions are obtained by hydrothermal reaction of water-soluble salts of rare earth metals with alkalis.
6. The preparation method according to claim 5, characterized in that: The water-soluble salt is one or more of nitrates, sulfates, chlorides, and acetates.
7. The preparation method according to claim 5, characterized in that: The alkali is NH3·H2O.
8. The preparation method according to claim 5, characterized in that: The hydrothermal reaction is carried out at a temperature of 110-130℃ for 8-16 hours.
9. An upconversion luminescent transparent ceramic material obtained by the preparation method according to any one of claims 1-8.
10. The application of the upconversion luminescent transparent ceramic material according to claim 9 in lasers, temperature sensors, and lighting.