Cr < 3 + >-activated tantalum-based oxide broadband near-infrared luminescent material and preparation method thereof

Abstract

The invention discloses a Cr < 3 + > activated tantalum-based oxide broadband near-infrared luminescent material and a preparation method thereof. Raw materials containing lutetium, yttrium, calcium, gallium, tantalum and chromium are mixed according to a specific stoichiometric ratio and then sintered at high temperature to prepare the Cr < 3 + >-activated tantalum-based oxide broadband near-infrared luminescent material, and the luminous intensity of the Cr < 3 + >-activated tantalum-based oxide broadband near-infrared luminescent material under 330 nm excitation is 12.37 times that of blue light (448 nm) excitation; the near-infrared luminescent material has good thermal stability, and the luminous intensity of the near-infrared luminescent material under excitation of near ultraviolet light (330 nm) at 150 DEG C can reach 13.70 times that of the near-infrared luminescent material under excitation of blue light (448 nm); the near-infrared light-emitting material disclosed by the invention has the advantages of simplicity and convenience in synthesis, high light-emitting intensity under near-ultraviolet excitation and the like, and can be applied as a near-infrared light conversion material excited by a near-ultraviolet chip.

Description

Technical Field

[0001] This invention relates to the field of inorganic luminescent materials technology, specifically to a Cr... 3+ Activated tantalum-based oxide broadband near-infrared luminescent materials and their preparation methods. Background Technology

[0002] Near-infrared luminescent materials, as functional materials capable of converting excitation light of specific wavelengths into near-infrared light, have significant application value in near-infrared imaging, biomedical detection, plant growth illumination, and high-energy ray detection. Among these, transition metal ions (such as Cr) are particularly valuable. 3+ Inorganic oxide luminescent materials, which serve as activators, have become a research hotspot in recent years due to their high chemical stability, excellent luminescent performance, and relatively low preparation cost.

[0003] Cr 3+ Ions due to their unique 3D 3 The electronic configuration of Cr readily produces broadband near-infrared emission in a crystal field, and its luminescence performance is closely related to the crystal field environment. 3+ Most activated oxide near-infrared luminescent materials exhibit high luminous intensity under blue light excitation, but low luminous efficiency under near-ultraviolet light excitation, which to some extent limits their application in matching with near-ultraviolet LED chips.

[0004] Garnet oxides are considered promising luminescent matrix materials due to their stable crystal structure and suitable crystal field environment. Their luminescence properties can be optimized by introducing different activating ions and doping. However, existing garnet oxide near-infrared luminescent materials still have shortcomings in terms of excitation wavelength coverage and luminescence intensity under near-ultraviolet excitation, making it difficult to meet the requirements of broadband near-infrared emission, different excitation wavelengths, and stable operation in practical applications.

[0005] Therefore, it is necessary to develop a Cr-based luminescent material that can be effectively excited by near-ultraviolet-visible light and exhibits high luminescence intensity and good thermal stability under near-ultraviolet excitation. 3+ Activating tantalum-based oxide broadband near-infrared luminescent materials is of great significance for expanding the application scenarios of near-infrared luminescent materials. Summary of the Invention

[0006] This invention provides a Cr 3+ An activated tantalum-based oxide broadband near-infrared luminescent material and its preparation method are disclosed. This luminescent material is prepared by mixing raw materials containing lutetium, yttrium, calcium, gallium, tantalum, and chromium in a specific stoichiometric ratio and then sintering at high temperature. Its near-infrared luminescence intensity under near-ultraviolet light excitation is significantly superior to that under blue light excitation, solving the problem of Cr... 3+The problem of low near-ultraviolet excitation efficiency in activated oxide broadband near-infrared luminescent materials.

[0007] This invention is achieved through the following technical solutions:

[0008] The first objective of this invention is to provide a Cr 3+ Activated tantalum-based oxide broadband near-infrared luminescent material, wherein the chemical composition of the near-infrared luminescent material is expressed as: Lu 0.7 Y 0.3 Ca2Ga 4-x TaO 12 :xCr 3+ , where x is the amount of Cr substitution, and 0 < x < 1, preferably 0.01 ≤ x ≤ 0.13.

[0009] The second object of the present invention is to provide the above-mentioned Cr 3+ A method for preparing activated tantalum-based oxide broadband near-infrared luminescent materials includes the following steps: weighing raw materials containing lutetium, yttrium, calcium, gallium, tantalum, and chromium according to their chemical composition, wherein the stoichiometric ratio of the metal elements lutetium, yttrium, calcium, gallium, tantalum, and chromium is 0.7:0.3:2:4-x:1:x, where x is the amount of Cr substitution, and 0 < x < 1; grinding and mixing thoroughly and uniformly; placing the mixture in a reaction vessel; sintering in an air atmosphere; and grinding after cooling to room temperature to obtain the luminescent material.

[0010] Preferably, the sintering temperature is 1350-1400℃, and the sintering time is 6 hours. More preferably, sintering is carried out by heating from room temperature to 1400℃ at a rate of 3-5℃ / min.

[0011] Preferably, the raw material containing lutetium is selected from one or more of lutetium oxide, lutetium oxalate, lutetium carbonate, and lutetium nitrate.

[0012] Preferably, the yttrium-containing raw material is selected from one or more of yttrium oxide, yttrium oxalate, yttrium carbonate, and yttrium nitrate.

[0013] Preferably, the calcium-containing raw material is selected from one or more of calcium carbonate, calcium bicarbonate, and calcium oxalate.

[0014] Preferably, the gallium-containing raw material is selected from gallium oxide.

[0015] Preferably, the raw material containing tantalum is selected from tantalum oxide.

[0016] Preferably, the chromium-containing raw material is selected from chromium oxide.

[0017] A third objective of this invention is to provide the aforementioned Cr 3+Application of activated tantalum-based oxide broadband near-infrared luminescent materials as near-infrared light conversion materials.

[0018] Preferably, the near-infrared light conversion material is a near-infrared light conversion material excited by a near-ultraviolet or blue LED chip.

[0019] The fourth object of the present invention is to provide the above-mentioned Cr 3+ Applications of activated tantalum-based oxide broadband near-infrared luminescent materials in high-energy ray detection and plant growth illumination.

[0020] A fifth object of the present invention is to provide a light-emitting device, comprising a phosphor and an excitation light source, wherein the phosphor comprises the aforementioned Cr 3+ Activated tantalum-based oxide broadband near-infrared luminescent material.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] (1) The near-infrared luminescent material of the present invention can be excited by near-ultraviolet-visible light of 280-690 nm, with an emission peak covering 600-850 nm. Moreover, its near-infrared luminescence intensity under near-ultraviolet light excitation is much higher than its luminescence intensity under blue light excitation. Specifically, its luminescence intensity under 330 nm excitation is 12.37 times that under blue light (448 nm) excitation, which is significantly different from other Cr materials. 3+ Activation of oxide broadband near-infrared luminescent materials (for general Cr) 3+ For activated oxide broadband near-infrared phosphors, the luminescence intensity under blue light excitation is usually much higher than that under ultraviolet light excitation.

[0023] (2) The near-infrared luminescent material of the present invention has good thermal stability. At 150°C, the luminescence intensity under near-ultraviolet light (330 nm) excitation can reach 13.70 times that under blue light (448 nm) excitation.

[0024] (3) The near-infrared luminescent material of the present invention has the advantages of simple synthesis and high luminescence intensity under near-ultraviolet light excitation, and can be used as a near-infrared light conversion material excited by near-ultraviolet chip. Attached Figure Description

[0025] Figure 1 The Cr prepared in Example 1 3+ X-ray powder diffraction pattern of activated tantalum-based oxide broadband near-infrared luminescent material.

[0026] Figure 2 The Cr prepared in Example 2 3+ Excitation spectrum of activated tantalum-based oxide broadband near-infrared luminescent material.

[0027] Figure 3 The Cr prepared in Example 2 3+ The emission spectra of the activated tantalum-based oxide broadband near-infrared luminescent material were obtained at room temperature by excitation at 330 nm and 448 nm, respectively.

[0028] Figure 4 The Cr prepared in Example 3 3+ The emission spectra of the activated tantalum-based oxide broadband near-infrared luminescent material were obtained by excitation at 150 °C using 330 nm and 448 nm, respectively. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0030] Example 1

[0031] Weigh out 0.2786 g of lutetium oxide (Lu₂O₃), 0.0677 g of yttrium oxide (Y₂O₃), 0.4003 g of calcium carbonate (CaCO₃), 0.7479 g of gallium oxide (Ga₂O₃), 0.4419 g of tantalum oxide (Ta₂O₅), and 0.0015 g of chromium oxide (Cr₂O₃). Grind and mix these raw materials thoroughly in an agate mortar until homogeneous. Place the mixture in a corundum crucible and heat it from room temperature to 1350 °C in air at a rate of 5 °C / min. After reaching the preset temperature, maintain this temperature for 6 hours. After cooling naturally, grind the mixture until homogeneous to obtain Cr₂O₃. 3+ Activated tantalum-based oxide broadband near-infrared luminescent material Lu 0.7 Y 0.3 Ca2Ga 3.99 TaO 12 0.01Cr 3+ .

[0032] The prepared near-infrared luminescent material was subjected to X-ray diffraction. Figure 1 It can be seen that the obtained sample is a pure phase.

[0033] Example 2

[0034] Weigh out 0.2786 g of lutetium oxide (Lu₂O₃), 0.0677 g of yttrium oxide (Y₂O₃), 0.4003 g of calcium carbonate (CaCO₃), 0.7404 g of gallium oxide (Ga₂O₃), 0.4419 g of tantalum oxide (Ta₂O₅), and 0.0076 g of chromium oxide (Cr₂O₃). Grind and mix the above raw materials thoroughly in an agate mortar until homogeneous. Place the mixture in a corundum crucible and heat it from room temperature to 1400 °C in air at a heating rate of 5 °C / min. After reaching the preset temperature, maintain the temperature for 6 hours. After the process is complete, allow it to cool naturally and grind it until homogeneous to obtain the near-infrared luminescent material Lu. 0.7 Y 0.3 Ca2Ga 3.95 TaO 12 0.05Cr 3+ .

[0035] The prepared near-infrared luminescent material was subjected to spectral testing. Figure 2 It can be seen that the obtained sample has excitation peaks between 280-400 nm, 400-550 nm, and 550-690 nm, among which the excitation peak intensity between 280-400 nm is much higher than the other two excitation peaks. Figure 3 It can be seen that the luminescence intensity of the sample under 330 nm excitation is 12.37 times that under 448 nm excitation.

[0036] Example 3

[0037] Weigh out 0.2786 g of lutetium oxide (Lu₂O₃), 0.0677 g of yttrium oxide (Y₂O₃), 0.4003 g of calcium carbonate (CaCO₃), 0.7254 g of gallium oxide (Ga₂O₃), 0.4419 g of tantalum oxide (Ta₂O₅), and 0.0198 g of chromium oxide (Cr₂O₃). Grind and mix the above raw materials thoroughly in an agate mortar until homogeneous. Place the mixture in a corundum crucible and heat it from room temperature to 1400 °C in air at a heating rate of 5 °C / min. After reaching the preset temperature, maintain the temperature for 6 hours. After the process is complete, allow it to cool naturally and grind it until homogeneous to obtain the near-infrared luminescent material Lu. 0.7 Y 0.3 Ca2Ga 3.87 TaO 12 0.13Cr 3+ .

[0038] The prepared near-infrared luminescent material was subjected to spectral testing at 150℃. Figure 4 It can be seen that the luminescence intensity of the sample under 330 nm excitation is 13.70 times that under 448 nm excitation.

Claims

1. A type of Cr 3+ Activated tantalum-based oxide broadband near-infrared luminescent material, characterized in that, The chemical composition of the near-infrared luminescent material is expressed as: Lu 0.7 Y 0.3 Ca2Ga 4-x TaO 12 :xCr 3+ , where x is the amount of Cr substitution, and 0 < x < 1.

2. The Cr according to claim 1 3+ Activated tantalum-based oxide broadband near-infrared luminescent material, characterized in that, 0.01≤x≤0.13。 3. The Cr as described in claim 1 or 2 3+ A method for preparing activated tantalum-based oxide broadband near-infrared luminescent materials, characterized in that, Includes the following steps: According to Lu 0.7 Y 0.3 Ca2Ga 4-x TaO 12 :xCr 3+ Raw materials containing lutetium, yttrium, calcium, gallium, tantalum and chromium were weighed according to the stoichiometric ratio, thoroughly ground and mixed, placed in a reaction vessel, sintered in an air atmosphere, cooled to room temperature and ground to obtain the target luminescent material.

4. The preparation method according to claim 3, characterized in that, The sintering temperature is 1350-1400℃, and the sintering time is 6 hours.

5. The preparation method according to claim 4, characterized in that, Sintering is carried out by heating from room temperature to 1400℃ at a rate of 3-5℃ / min.

6. The preparation method according to claim 3, characterized in that, The raw materials containing lutetium are selected from one or more of lutetium oxide, lutetium oxalate, lutetium carbonate, and lutetium nitrate; the raw materials containing yttrium are selected from one or more of yttrium oxide, yttrium oxalate, yttrium carbonate, and yttrium nitrate; and the raw materials containing calcium are selected from one or more of calcium carbonate, calcium bicarbonate, and calcium oxalate.

7. The preparation method according to claim 3, characterized in that, The raw material containing gallium is selected from gallium oxide; the raw material containing tantalum is selected from tantalum oxide; and the raw material containing chromium is selected from chromium oxide.

8. The Cr as described in claim 1 or 2 3+ Application of activated tantalum-based oxide broadband near-infrared luminescent materials as near-infrared light conversion materials.

9. The Cr as described in claim 1 or 2 3+ Applications of activated tantalum-based oxide broadband near-infrared luminescent materials in high-energy ray detection and plant growth illumination.

10. A light-emitting device, characterized in that, It includes a phosphor and an excitation source, wherein the phosphor comprises the Cr as described in claim 1 or 2. 3+ Activated tantalum-based oxide broadband near-infrared luminescent material.

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