Aluminate near-infrared fluorescent powder as well as preparation method and application thereof
By preparing CeMgAl11-xO19:xCr3+ aluminate phosphor, the problems of low efficiency and poor thermal stability of existing near-infrared luminescent materials have been solved, achieving efficient and stable near-infrared luminescence, which is suitable for night vision, vein imaging and full-spectrum illumination.
Patent Information
- Application Number
- CN202511983477.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-26
- Publication Date
- 2026-03-17
Smart Images
Figure CN121674064A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of inorganic luminescent materials technology, and in particular to an aluminate near-infrared phosphor, its preparation method, and its application. Background Technology
[0002] Near-infrared phosphors with emission wavelengths in the 700–1100 nm range have attracted significant attention due to their wide applications in full-spectrum lighting, biomedical imaging, plant growth illumination, food safety detection, and night vision. Developing near-infrared luminescent materials that combine high quantum efficiency, excellent thermal quenching resistance, and efficient matching with the emission spectra of commercial near-ultraviolet / blue LED chips has become a core key to driving the development of near-infrared solid-state light source technology. Cr with a 3d3 electronic configuration... 3+ Ions, due to their high sensitivity to the crystal field environment, offer a unique opportunity to optimize near-infrared luminescence performance through matrix structure modulation. However, currently reported near-infrared luminescent materials (including Cr) 3+ Doped systems generally face bottlenecks such as low luminous efficiency and poor thermal stability, which seriously restrict their practical applications. Summary of the Invention
[0003] The purpose of this invention is to provide an aluminate near-infrared phosphor, its preparation method, and its applications. The aluminate near-infrared phosphor of this invention uses CeMgAl... 11 O 19 As a matrix, through Cr doping 3+ It achieves efficient near-infrared emission, with high luminous efficiency and high thermal stability.
[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides an aluminate near-infrared phosphor with the chemical formula CeMgAl. 11-x O 19 :xCr 3+ , where 0.02≤x≤0.2.
[0005] Preferably, 0.05≤x≤0.18.
[0006] Preferably, 0.08≤x≤0.16.
[0007] Preferably, the aluminate near-infrared phosphor emits wavelengths of 600-900 nm and peak wavelengths of 690-720 nm when excited by near-ultraviolet and blue light wavelengths of 380-460 nm.
[0008] This invention provides a method for preparing the aluminate near-infrared phosphor described in the above technical solution, comprising the following steps: The Ce compound, Mg compound, Al compound, Cr compound and flux were mixed and ground to obtain a mixed precursor. The mixed precursor was sintered in a reducing atmosphere to obtain aluminate near-infrared phosphor.
[0009] Preferably, the Ce compound is one or more selected from cerium oxide, cerium carbonate, cerium oxalate, cerium acetate, cerium nitrate, and cerium hydroxide; The Mg compound is one or more of magnesium oxide, magnesium carbonate, magnesium oxalate, magnesium acetate, magnesium nitrate, and magnesium hydroxide. The Al compound is one or more of aluminum oxide, aluminum carbonate, aluminum oxalate, aluminum acetate, aluminum nitrate, and aluminum hydroxide. The Cr compound is one or more of chromium oxide, chromium carbonate, chromium oxalate, chromium acetate, chromium nitrate, and chromium hydroxide.
[0010] Preferably, the flux includes H3BO3, NH4Cl or Li2CO3; the mass ratio of the flux to the aluminate near-infrared phosphor is 0.14:1.
[0011] Preferably, the reducing atmosphere, by volume fraction, consists of 5-15% H2 and 85-95% protective gas, wherein the protective gas is N2 or Ar.
[0012] Preferably, the sintering temperature is 1400~1600℃, and the holding time is ≤6h.
[0013] This invention provides applications of the aluminate near-infrared phosphor described in the above-described technical solution or the aluminate near-infrared phosphor prepared by the above-described technical solution in the fields of night vision, vein imaging, plant growth supplemental lighting, or full-spectrum illumination.
[0014] This invention provides an aluminate near-infrared phosphor with the chemical formula CeMgAl. 11-x O 19 :xCr 3+ Where 0.02≤x≤0.2, the phosphor is Cr. 3+ Activated aluminate near-infrared phosphor with a magnetoplumble structure. This near-infrared phosphor contains a very strong and stable Al-O bond network that runs throughout the entire crystal, and Cr... 3+ Occupying the center of a rigid [AlO6] octahedron, the rigid lattice suppresses nonradiative transitions. Therefore, the near-infrared phosphor of this invention has excellent thermal stability and luminous efficiency, and can achieve high-efficiency luminescence under near-ultraviolet to blue light excitation. It is suitable for night vision lighting, vein imaging, plant growth supplementary lighting, full-spectrum lighting and other fields.
[0015] This invention optimizes the component design and sintering process, resulting in phosphors with high quantum efficiency and thermal stability. When x=0.1, the external quantum efficiency of the aluminate near-infrared phosphor can reach 54.7%, and its luminescence intensity can be maintained at 82.2% at room temperature at 225℃. When x=0.2, the external quantum efficiency can reach 52.8%, and its luminescence intensity can be maintained at 79% at room temperature at 225℃, demonstrating excellent thermal stability.
[0016] This invention employs a high-temperature solid-state method, which uses inexpensive raw materials, has a simple process flow, and allows for controllable preparation conditions. Attached Figure Description
[0017] Figure 1 The X-ray diffraction patterns of the near-infrared phosphors prepared in Examples 1-8 are shown below. Figure 2 The near-infrared phosphor CeMgAl prepared in Example 3 10.9 O 19 0.1Cr 3+ Excitation and emission spectra; Figure 3 The near-infrared phosphor CeMgAl prepared in Example 8 10.8 O 19 0.2Cr 3+ Excitation and emission spectra; Figure 4 The near-infrared phosphor CeMgAl prepared in Example 3 10.9 O 19 0.1Cr 3+ Quantum efficiency test spectrum; Figure 5 The near-infrared phosphor CeMgAl prepared in Example 8 10.8 O 19 0.2Cr 3+ Quantum efficiency test spectrum; Figure 6 The near-infrared phosphor CeMgAl prepared in Example 3 10.9 O 19 0.1Cr 3+ The temperature-varying spectrum; Figure 7 The near-infrared phosphor CeMgAl prepared in Example 8 10.8 O 19 0.2Cr 3+ The temperature-varying spectrum; Figure 8 For Comparative Example 1, CeMgAl 11 O 19 XRD pattern of powder. Detailed Implementation
[0018] In this invention, unless otherwise specified, the raw materials or reagents required for preparation are all commercially available products well known to those skilled in the art.
[0019] This invention provides an aluminate near-infrared phosphor with the chemical formula CeMgAl. 11-x O 19 :xCr 3+ , where 0.02≤x≤0.2.
[0020] As a preferred embodiment of the present invention, 0.05≤x≤0.18, more preferably 0.06≤x≤0.16, even more preferably 0.08≤x≤0.12, and even more preferably 0.09~0.1.
[0021] In this invention, the aluminate near-infrared phosphor emits wavelengths of 600-900 nm and has a peak wavelength of 690-720 nm when excited by near-ultraviolet and blue light wavelengths (380-460 nm).
[0022] This invention provides a method for preparing the aluminate near-infrared phosphor described in the above technical solution, comprising the following steps: The Ce compound, Mg compound, Al compound, Cr compound and flux were mixed and ground to obtain a mixed precursor. The mixed precursor was sintered in a reducing atmosphere to obtain aluminate near-infrared phosphor.
[0023] In this invention, the Ce compound is preferably one or more of cerium oxide, cerium carbonate, cerium oxalate, cerium acetate, cerium nitrate, and cerium hydroxide, and more preferably CeO2.
[0024] In this invention, the Mg compound is preferably one or more of magnesium oxide, magnesium carbonate, magnesium oxalate, magnesium acetate, magnesium nitrate, and magnesium hydroxide, and more preferably MgO.
[0025] The Al compound is preferably one or more of aluminum oxide, aluminum carbonate, aluminum oxalate, aluminum acetate, aluminum nitrate, and aluminum hydroxide, and more preferably Al2O3.
[0026] The Cr compound is preferably one or more of chromium oxide, chromium carbonate, chromium oxalate, chromium acetate, chromium nitrate, and chromium hydroxide, and more preferably Cr2O3.
[0027] When the Ce compound, Mg compound, Al compound, or Cr compound is two or more of the above, the present invention does not have a special limitation on the ratio of different types of compounds, and any ratio is acceptable.
[0028] In this invention, the flux preferably includes H3BO3, NH4Cl or Li2CO3; the mass ratio of the flux to the aluminate near-infrared phosphor is preferably 0.14:1.
[0029] In this invention, the Ce compound, Mg compound, Al compound, Cr compound, and flux are mixed, then anhydrous ethanol is added and mixed thoroughly before grinding in an agate mortar. This invention does not have a specific limitation on the amount of anhydrous ethanol used; it can be adjusted according to requirements to ensure uniform mixing of the materials.
[0030] The present invention does not have any special limitations on the grinding process; the materials can be mixed evenly according to a process known in the art.
[0031] In this invention, the reducing atmosphere is preferably composed of 5-15% H2 and 85-95% protective gas by volume fraction; the protective gas is preferably N2 or Ar; and the reducing atmosphere is more preferably 5% H2 + 95% N2.
[0032] In this invention, the sintering temperature is preferably 1400~1600℃, more preferably 1450~1580℃, even more preferably 1500~1550℃, and the holding time is preferably ≤6h, more preferably 1~6h; the heating rate to the sintering temperature is preferably 5℃ / min.
[0033] After the sintering is completed, the present invention preferably cools the obtained product to room temperature and grinds it evenly to obtain aluminate near-infrared phosphor.
[0034] This invention provides applications of the aluminate near-infrared phosphor described in the above-described technical solutions, or the aluminate near-infrared phosphor prepared by the above-described preparation methods, in the fields of night vision, vein imaging, supplemental lighting for plant growth, or full-spectrum illumination. This invention does not impose any particular limitation on the methods used for these applications; methods well-known in the art can be followed.
[0035] The specific embodiments of the present invention are described in detail below, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
[0036] Unless otherwise specified, the experimental methods described in the various embodiments of this invention are conventional methods; unless otherwise specified, the reagents and raw materials described below are all commercially available.
[0037] Example 1
[0038] According to the general chemical formula CeMgAl 10.95 O 19 0.05Cr3+ According to the stoichiometric ratio, CeO2 (0.2246g), MgO (0.0526g), Al2O3 (0.7283g), and Cr2O3 (0.0050g) were weighed out, and 0.1400g of H3BO3 was added. 2mL of anhydrous ethanol was added and mixed thoroughly. The mixture was then ground in an agate mortar. The ground powder was placed in an alumina crucible, which was then placed in a tube furnace. The temperature was increased to 1550℃ at a rate of 5℃ / min, and sintered at a constant temperature for 6 hours under a reducing atmosphere (5%H2 + 95%N2). After cooling to room temperature, the powder was thoroughly ground to obtain the near-infrared phosphor CeMgAl. 10.95 O 19 0.05Cr 3+ .
[0039] Example 2
[0040] According to CeMgAl 10.93 O 19 0.07Cr 3+ According to the stoichiometric ratio, CeO2 (0.2244g), MgO (0.0526g), Al2O3 (0.7265g), and Cr2O3 (0.0069g) were weighed, and 0.1400g of H3BO3 was added. The other steps were the same as in Example 1 to obtain the near-infrared phosphor CeMgAl. 10.93 O 19 0.07Cr 3+ .
[0041] Example 3
[0042] According to CeMgAl 10.9 O 19 0.1Cr 3+ According to the stoichiometric ratio, CeO2 (0.2242g), MgO (0.0525g), Al2O3 (0.7238g), and Cr2O3 (0.0099g) were weighed, and 0.1400g of H3BO3 was added. The other steps were the same as in Example 1 to obtain the near-infrared phosphor CeMgAl. 10.9 O 19 0.1Cr 3+ .
[0043] Example 4
[0044] According to CeMgAl 10.88 O 19 0.12Cr 3+According to the stoichiometric ratio, CeO2 (0.2240g), MgO (0.0525g), Al2O3 (0.7220g), and Cr2O3 (0.0119g) were weighed, and 0.1400g of H3BO3 was added. The other steps were the same as in Example 1 to obtain the near-infrared phosphor CeMgAl. 10.88 O 19 0.12Cr 3+ .
[0045] Example 5
[0046] According to CeMgAl 10.86 O 19 0.14Cr 3+ According to the stoichiometric ratio, CeO2 (0.2239g), MgO (0.0524g), Al2O3 (0.7202g), and Cr2O3 (0.0138g) were weighed, and 0.1400g of H3BO3 was added. The other steps were the same as in Example 1 to obtain the near-infrared phosphor CeMgAl. 10.86 O 19 0.14Cr 3+ .
[0047] Example 6
[0048] According to CeMgAl 10.84 O 19 0.16Cr 3+ According to the stoichiometric ratio, CeO2 (0.2238g), MgO (0.0524g), Al2O3 (0.7184g), and Cr2O3 (0.0158g) were weighed, and 0.1400g of H3BO3 was added. The other steps were the same as in Example 1 to obtain the near-infrared phosphor CeMgAl. 10.84 O 19 0.16Cr 3+ .
[0049] Example 7
[0050] According to CeMgAl 10.82 O 19 0.18Cr 3+ According to the stoichiometric ratio, CeO2 (0.2236g), MgO (0.0524g), Al2O3 (0.7166g), and Cr2O3 (0.0178g) were weighed, and 0.1400g of H3BO3 was added. The other steps were the same as in Example 1 to obtain the near-infrared phosphor CeMgAl. 10.82 O 19 0.18Cr 3+ .
[0051] Example 8
[0052] According to CeMgAl 10.8 O 19 0.2Cr 3+ According to the stoichiometric ratio, CeO2 (0.2235g), MgO (0.0523g), Al2O3 (0.7149g), and Cr2O3 (0.0197g) were weighed, and 0.1400g of H3BO3 was added. The other steps were the same as in Example 1 to obtain the near-infrared phosphor CeMgAl. 10.8 O 19 0.2Cr 3+ .
[0053] Comparative Example 1
[0054] The only difference from Example 1 is that Cr2O3 is not added, resulting in CeMgAl. 11 O 19 Powder.
[0055] Performance testing
[0056] Figure 1 The X-ray diffraction patterns of the near-infrared phosphors prepared in Examples 1-8 are shown; Figure 1 It can be seen that the obtained product is a pure phase with no impurity phases appearing.
[0057] Figure 2 The near-infrared phosphor CeMgAl prepared in Example 3 10.9 O 19 0.1Cr 3+ The excitation and emission spectra; by Figure 2 It is known that this near-infrared phosphor can be excited by near-ultraviolet and blue light wavelengths (380~460 nm), with an emission wavelength of 600~900 nm and a peak wavelength of 690~720 nm.
[0058] Figure 3 The near-infrared phosphor CeMgAl prepared in Example 8 10.8 O 19 0.2Cr 3+ The excitation and emission spectra; by Figure 3 It is known that this near-infrared phosphor can be excited by near-ultraviolet and blue light wavelengths (380~460 nm), with an emission wavelength of 600~900 nm and a peak wavelength of 690~720 nm.
[0059] Figure 4 The near-infrared phosphor CeMgAl prepared in Example 3 10.9 O 19 0.1Cr 3+ The quantum efficiency test spectrum; by Figure 4 It can be seen that the external quantum efficiency of this phosphor can reach 54.7%.
[0060] Figure 5 The near-infrared phosphor CeMgAl prepared in Example 8 10.8 O 19 0.2Cr 3+ The quantum efficiency test spectrum; by Figure 5 It can be seen that the external quantum efficiency of this phosphor can reach 52.8%.
[0061] Figure 6 The near-infrared phosphor CeMgAl prepared in Example 3 10.9 O 19 0.1Cr 3+ The temperature-dependent spectrum of the phosphor is shown in the inset, which illustrates the change in the integrated intensity of the phosphor with temperature. Figure 6 It can be seen that at 225℃, its luminescence intensity can be maintained at 82.2% of that at room temperature.
[0062] Figure 7 The near-infrared phosphor CeMgAl prepared in Example 8 10.8 O 19 0.2Cr 3+ The temperature-dependent spectrum of the phosphor is shown in the inset, which illustrates the change in the integrated intensity of the phosphor with temperature. Figure 7 It can be seen that at 225℃, its luminous intensity can be maintained at 79% of that at room temperature.
[0063] Figure 8 For Comparative Example 1, CeMgAl 11 O 19 The XRD pattern, by Figure 8 It can be seen that the obtained product is a pure phase with no impurity phases appearing.
[0064] In addition, CeMgAl in Comparative Example 1 11 O 19 It does not emit light under 405nm excitation and has no luminous efficiency.
[0065] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. An aluminate near-infrared fluorescent powder, characterized by, Chemical formula: CeMgAl 11-x O 19 : xCr 3+ wherein 0.02≤x≤0.
2.
2. The aluminate near-infrared fluorescent powder according to claim 1, characterized in that, 0.05≤x≤0.18。 3. The aluminate near-infrared fluorescent powder according to claim 1, characterized in that, 0.08≤x≤0.16。 4. The aluminate near-infrared fluorescent powder according to claim 1, characterized in that, The aluminate near-infrared fluorescent powder emits light with a wavelength of 600-900 nm and a peak wavelength of 690-720 nm under excitation of near-ultraviolet light and blue light with a wavelength of 380-460 nm.
5. The method for preparing the aluminate near-infrared fluorescent powder according to any one of claims 1-4, characterized in that, The method comprises the following steps: The Ce compound, the Mg compound, the Al compound, the Cr compound and a fluxing agent are mixed and ground to obtain a mixed precursor; The mixed precursor is sintered in a reducing atmosphere to obtain the aluminate near-infrared fluorescent powder.
6. The production method according to claim 5, wherein The Ce compound is one or more of cerium oxide, cerium carbonate, cerium oxalate, cerium acetate, cerium nitrate and cerium hydroxide; The Mg compound is one or more of magnesium oxide, magnesium carbonate, magnesium oxalate, magnesium acetate, magnesium nitrate and magnesium hydroxide; The Al compound is one or more of aluminum oxide, aluminum carbonate, aluminum oxalate, aluminum acetate, aluminum nitrate and aluminum hydroxide; The Cr compound is one or more of chromium oxide, chromium carbonate, chromium oxalate, chromium acetate, chromium nitrate and chromium hydroxide.
7. The preparation method according to claim 5, characterized in that, The fluxing agent comprises H3BO3, NH4Cl or Li2CO3, and the mass ratio of the fluxing agent to the aluminate near-infrared fluorescent powder is 0.14:
1.
8. The preparation method according to claim 5, characterized in that, The reducing atmosphere comprises 5-15% H2 and 85-95% protective gas, and the protective gas is N2 or Ar.
9. The preparation method according to claim 5, characterized in that, The sintering temperature is 1400-1600 ℃, and the holding time is ≤6 h.
10. Application of the aluminate near-infrared fluorescent powder in any one of claims 1-4 or the aluminate near-infrared fluorescent powder prepared by the method in any one of claims 5-9 in the fields of night vision, intravenous imaging, plant growth light supplement or full-spectrum lighting.