Chromium ion single-doped ultra-wideband near-infrared fluorescent material, preparation method thereof and LED device

Abstract

The invention relates to a chromium ion single-doped ultra-wideband near-infrared fluorescent material, a preparation method thereof and an LED device, and belongs to the technical field of luminescent materials. The chemical composition formula of the material is Ca2Sc1-yYyGa3-3xSn2O12: xCr, x is larger than or equal to 0.003 and smaller than or equal to 0.10, and y is larger than or equal to 0.00 and smaller than or equal to 1.00. The material is high in phase purity, simple in preparation process, simple and convenient to operate, environment-friendly and high in synthesis efficiency. Under excitation of 475-500 nm, the emission spectrum of the material covers the range of 600-1600 nm, the material has high luminous intensity in a first near-infrared region (about 855 nm) and a second near-infrared region (about 1300 nm), and the full width at half maximum can reach 200-655 nm. Meanwhile, the material has good absorption in the range of 400-700 nm, can be effectively matched with a commercial blue light LED chip, and is suitable for preparing a high-performance near-infrared LED light source. Compared with the prior art, the material provided by the invention not only can realize ultra-wideband emission covering a first near-infrared area and a second near-infrared area, but also is adjustable in emission peak position and high in absorption characteristic and commercial blue light chip compatibility, and is beneficial to development of high-efficiency and high-stability near-infrared LED devices.

Description

Technical Field

[0001] This invention belongs to the field of inorganic luminescent materials technology, and particularly relates to a chromium ion-doped ultrawideband near-infrared fluorescent material, its preparation method, and LED device. Background Technology

[0002] Near-infrared light (especially in the 700-1700 nm band) has significant applications in biomedical imaging, non-destructive testing, night vision illumination, and spectral analysis due to its unique advantages such as deep penetration into biological tissues, low autofluorescence interference, and minimal damage to biological tissues. Developing efficient, compact, and low-cost near-infrared light sources, particularly solid-state sources based on LED technology, is crucial for advancing related technologies.

[0003] Currently, the mainstream technical approach to realizing near-infrared LEDs is to combine near-infrared emitting materials with blue or ultraviolet LED chips. However, commonly used near-infrared emitting materials in existing technologies, such as certain transition metal ions (e.g., Mn), 4+ Broadband emission materials doped with rare earth ions (such as Nd) or rare earth ions (such as Nd) 3+ Er 3+ Even with doping, materials still have many limitations in performance. For example, Nd... 3+ Ions, Yb 3+ Most ion-activated materials have narrow emission bands, making it impossible to achieve ultra-wideband emission covering the near-infrared I (700-1000 nm) and near-infrared II (1000-1700 nm) regions, thus limiting their performance in applications requiring broad spectrum or specific wavelengths. Meanwhile, Yb 3+ Ions, Mn 4+ The excitation wavelength of the activated fluorescent material does not match well with the emission wavelength (420-490 nm) of commercially available high-efficiency blue LED chips, resulting in low light conversion efficiency of near-infrared LED devices. Furthermore, Yb 3+ Ions, Mn 4+ The emission peak position of activated fluorescent materials is fixed and cannot be adjusted, making it difficult to adapt to the needs of different application scenarios; while near-infrared luminescent materials such as quantum dot luminescent materials have problems such as complex synthesis processes, poor chemical stability or high cost.

[0004] Therefore, developing a near-infrared luminescent material that can be efficiently excited by commercial blue light chips, possesses ultra-wideband emission, and has tunable emission is of significant practical importance and technical value for preparing high-performance, multi-purpose near-infrared LED light sources to meet the growing demands of fields such as biomedicine and industrial testing. Summary of the Invention

[0005] This invention addresses the problems of narrow emission bands, poor compatibility with blue light chips, and insufficient thermal stability of existing near-infrared luminescent materials. It aims to provide an ultra-wideband near-infrared luminescent material that can be efficiently excited by blue light, has an emission band that covers both near-infrared I and II regions and is continuously tunable, and exhibits excellent thermal stability, as well as its preparation method.

[0006] The material uses chromium ions as an activator, and through matrix design and process control, it exhibits Cr-like properties under blue light excitation. 3+ With Cr 4+ The luminescent properties of Cr have enabled the realization of the transformation from traditional Cr 3+ The doped material emits in the near-infrared I region centered at ~855 nm, effectively extending to the near-infrared II region covering ~1300 nm. By adjusting the doping concentration of Cr ions and the material composition, the emission spectrum of this material can be continuously tuned in the range of 600–1600 nm, and the full width at half maximum (FWHM) can be significantly broadened from about 200 nm to 655 nm. Furthermore, it can still maintain about 84% of its luminescence intensity at a high temperature of 423 K, exhibiting excellent resistance to thermal quenching.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows:

[0008] A chromium ion-doped ultrawideband near-infrared fluorescent material, which uses Ca2ScGa3Sn2O 12 Using chromium ions as the activator and chromium as the matrix, its chemical formula is Ca2Sc 1-y Y y Ga 3-3x Sn2O 12 : xCr, where 0.003 ≤ x ≤ 0.10, 0.00 ≤ y ≤ 1.00.

[0009] This invention, by adjusting the chromium ion doping concentration and the cation substitution composition control strategy, can actively drive chromium ions to selectively enter six-coordinate or four-coordinate lattice sites, thereby achieving the selective doping of chromium ions. 3+ With Cr 4+ The proportion of luminescent centers can be controlled and adjusted, thereby enabling controllable tuning of the emission intensity and spectral distribution of the material in the near-infrared I and II regions.

[0010] For the chromium ion doping concentration strategy, the chemical composition is Ca2Sc 1-y Y y Ga 3-3x Sn2O 12The elemental ratio of xCr is preferably 0.005 ≤ x ≤ 0.07, and further preferably x = 0.02. At x = 0.02, the main peak of the material's emission spectrum has transitioned from 855 nm (NIR-I region) at x = 0.003 to 1300 nm (NIR-II region), and the integrated emission intensity is strongest at x = 0.02.

[0011] For the cationic component substitution strategy, the chemical composition is Ca2Sc 1-y Y y Ga 3-3x Sn2O 12 The elemental ratio of xCr is preferably such that when x = 0.02, 0 ≤ y ≤ 1; further, when x = 0.02, y = 1. When y = 1, the main peak of the material's emission spectrum can be controllably adjusted from 1300 nm when y = 0 to 780 nm when y = 1. More importantly, the material's luminescence intensity in the near-infrared region I is increased by 125 times, and it exhibits excellent thermal stability (84%@423 K) when y = 1.

[0012] Furthermore, this invention also provides a method for preparing chromium ion-doped ultrawideband near-infrared fluorescent materials, the method comprising the following steps:

[0013] Preferably, the chemical formula is Ca2Sc 1-y Y y Ga 3-3x Sn2O 12 : xCr, where 0.003 ≤ x ≤ 0.10, 0.00 ≤ y ≤ 1.00, wherein preferably 0.005 ≤ x ≤ 0.07, more preferably x = 0.02, y = 1.00.

[0014] Furthermore, the luminescent material includes Ca2ScGa 2.985 Cr 0.015 Sn2O 12 ,Ca2ScGa 2.97 Cr 0.03 Sn2O 12 ,Ca2ScGa 2.94 Cr 0.06 Sn2O 12 ,Ca2ScGa 2.91 Cr 0.09 Sn2O 12 ,Ca2ScGa 2.85 Cr 0.15 Sn2O 12 ,Ca2ScGa 2.79 Cr 0.21 Sn2O12 Ca2Sc 0.8 Y 0.2 Ga 2.94 Cr 0.06 Sn2O 12 Ca2Sc 0.6 Y 0.4 Ga 2.94 Cr 0.06 Sn2O 12 Ca2Sc 0.4 Y 0.6 Ga 2.94 Cr 0.06 Sn2O 12 Ca2Sc 0.2 Y 0.8 Ga 2.94 Cr 0.06 Sn2O 12 ,Ca2YGa 2.94 Cr 0.06 Sn2O 12 .

[0015] A method for preparing a chromium ion-doped ultrawideband near-infrared fluorescent material according to any one of the claims, comprising the following steps:

[0016] (1) According to the general formula Ca2Sc 1-y Y y Ga 3-3x Sn2O 12 Accurately weigh the raw materials according to the stoichiometric ratio of xCr (0.003 ≤ x ≤ 0.10, 0.00 ≤ y ≤ 1.00);

[0017] (2) Grind the raw materials from step (1) in an agate mortar to obtain a uniformly mixed mixture of raw materials;

[0018] (3) The raw material mixture from step (2) is calcined at high temperature in air atmosphere, and then naturally cooled and ground in air to obtain ultra-wideband near-infrared luminescent material.

[0019] Furthermore, the raw materials mentioned in step (1) are as follows:

[0020] The Ca source used is one or more of calcium oxide, calcium carbonate, or calcium nitrate;

[0021] The Y source used is one or more of yttrium oxide, yttrium carbonate, or yttrium nitrate;

[0022] The Sc source used is one or more of scandium oxide, scandium carbonate, or scandium nitrate;

[0023] The Ga source used is gallium oxide;

[0024] The Sn source used is one or more of tin nitrate and tin oxide;

[0025] The Cr source used is one or more of chromium nitrate, chromium oxide, or chromium chloride.

[0026] Preferably, the Ca source is calcium oxide (CaO), the Y source is yttrium oxide (Y2O3), the Sc source is scandium oxide (Sc2O3), the Ga source is gallium oxide (Ga2O3), the Sn source is oxygen dioxide (SnO2), and the Cr source is chromium trioxide (Cr2O3).

[0027] Furthermore, the raw material mixing method in step (2) is grinding, and the grinding time is 30-60 minutes.

[0028] Furthermore, the calcination in step (3) involves placing the raw material mixture in an alumina crucible and using a tube furnace or box furnace. The calcination temperature is 1400-1700 ℃, the heating rate is 1-10 ℃ / min, and the holding time is 4-10 hours. The atmosphere is an air atmosphere.

[0029] Furthermore, step (3) grinding involves grinding the sintered body in a mortar for 5-30 minutes to obtain an infrared luminescent material.

[0030] A near-infrared LED light source comprises a commercial blue LED chip and a near-infrared luminescent material for LED packaging; the luminescent material is the broadband near-infrared luminescent material described above.

[0031] The advantages and beneficial effects of this invention are as follows:

[0032] (1) Achieved efficient and ultra-wideband near-infrared emission (corresponding to claims 1-3): Under blue light excitation at 475-500 nm, this material can generate a continuous near-infrared emission spectrum covering 600-1600 nm, effectively covering the near-infrared I (NIR-I) and II (NIR-II) regions with better penetration into biological tissues, and the full width at half maximum (FWHM) can reach 200-655 nm. This ultra-wideband emission characteristic provides an ideal light source for near-infrared applications that require broad or continuous spectra (such as broadband imaging and multi-component analysis).

[0033] (2) The emission peak position is flexible and adjustable, and the application is highly targeted (corresponding to claims 1-3): by controlling the Cr in the material 3+ The doping concentration of ions (x value) and Y 3+ For Sc 3+The substitution ratio (y-value) allows for continuous and controllable adjustment of the emission peak between the near-infrared I region (approximately 855 nm) and the near-infrared II region (approximately 1300 nm). This enables customized optimization of the light source's output spectrum for different applications (such as focusing on NIR-I imaging or NIR-II deep penetration), greatly enhancing the material's application flexibility and applicability.

[0034] (3) Stable chemical and physical properties, and single phase (corresponding to claims 4-8): The prepared material has a pure phase garnet structure, with a single phase and no impurity phase interference, ensuring the stability and consistency of luminescence performance. This stable crystal structure helps the material maintain reliable luminescence performance under long-term use and different environmental conditions.

[0035] (4) The preparation method is simple, green and efficient (corresponding to claims 4-8): The material of the present invention is prepared by high temperature solid phase method. The preparation method is simple, easy to control, does not require complex equipment or harsh conditions, has high synthesis efficiency, and does not involve the use or generation of toxic and harmful substances. It is environmentally friendly and conducive to large-scale production and practical application.

[0036] (5) Excellent compatibility with commercial blue LED chips, which is beneficial for device efficiency (corresponding to claim 9): This material has strong light absorption in the 400-700 nm range, especially efficient absorption of light emitted by commercial blue LED chips (450-480 nm). This characteristic solves the key problem of mismatch between the excitation wavelength of traditional near-infrared materials and high-efficiency blue LED chips, and can be directly used to package high-efficiency and high-stability near-infrared LED devices, reducing dependence on special chips, simplifying device processes, and reducing costs.

[0037] In summary, this invention successfully integrates key advantages such as ultra-wideband emission, tunable peak position, and efficient blue light excitation, providing a novel near-infrared luminescent material with excellent performance, simple preparation, and high compatibility with existing LED chips. This lays the material foundation for the development of a new generation of high-performance, low-cost solid-state near-infrared light sources, and is expected to significantly promote the in-depth application and popularization of near-infrared light technology in fields such as biomedical imaging, disease diagnosis, night vision lighting, food inspection, and industrial non-destructive testing. Attached Figure Description

[0038] Figure 1 These are X-ray powder diffraction patterns of the ultrawideband near-infrared luminescent materials prepared in Comparative Example 1 and Preferred Examples 1-5 provided by the present invention.

[0039] Figure 2 The excitation spectra of the ultrawideband near-infrared luminescent materials prepared in Comparative Example 1 and Preferred Examples 1-5 are shown.

[0040] Figure 3 The emission spectra of the ultrawideband near-infrared luminescent materials prepared in Comparative Example 1 and Preferred Examples 1-5 are shown.

[0041] Figure 4 Normalized relative intensity variation graphs of the ultrawideband near-infrared luminescent materials prepared in Comparative Example 1 and Preferred Examples 1-5

[0042] Figure 5 These are X-ray diffraction (XRD) patterns of the ultra-wideband near-infrared luminescent materials prepared in Examples 2 and 6-10.

[0043] Figure 6 These are the normalized emission spectra of the ultrawideband near-infrared luminescent materials prepared in Examples 2 and 6-10.

[0044] Figure 7 The emission spectra are those of the ultrawideband near-infrared luminescent materials prepared in Examples 2 and 6-10.

[0045] Figure 8 This is the curve showing the relationship between the relative integral intensity of the emission spectrum of the ultrawideband near-infrared luminescent material prepared in Example 10 and temperature. Detailed Implementation

[0046] The technical solutions of the embodiments of the present invention will be clearly and thoroughly described below with reference to the accompanying drawings. The described embodiments are merely some embodiments of the present invention.

[0047] The technical solution of the present invention to solve the above-mentioned technical problems is:

[0048] Comparative Example 1

[0049] This embodiment provides Ca2ScGa 2.985 Cr 0.015 Sn2O 12 The preparation method (i.e., x = 0.005, y = 0).

[0050] To prepare 2 mmol of the target product, 0.4004 g of CaCO3, 0.1379 g of Sc2O3, 0.5595 g of Ga2O3, 0.6028 g of SnO2, and 0.0023 g of Cr2O3 were weighed according to stoichiometric ratios, with a total mass of 1.7029 g for the mixed compound. The mixture was placed in an agate mortar and ground for 30 minutes until homogeneous. The resulting mixture was transferred to an alumina crucible and heated to 1400°C in an air atmosphere in a box furnace. After maintaining this temperature at 1400°C for 6 hours, the mixture was allowed to cool naturally to room temperature. The naturally cooled sample was then ground uniformly in an agate mortar to obtain the product with the chemical formula Ca2ScGa 2.985 Cr0.015 Sn2O 12 Ultra-wideband near-infrared luminescent materials.

[0051] Example 1

[0052] This embodiment provides Ca2ScGa 2.97 Cr 0.03 Sn2O 12 The preparation method (i.e., x = 0.01, y = 0).

[0053] To prepare 2 mmol of the target product, 0.4004 g of CaCO3, 0.1379 g of Sc2O3, 0.5567 g of Ga2O3, 0.6028 g of SnO2, and 0.0046 g of Cr2O3 were weighed according to stoichiometric ratios, with a total mass of 1.7024 g for the mixed compound. The mixture was then ground in an agate mortar for 30 minutes until homogeneous. The resulting mixture was transferred to an alumina crucible and heated to 1400°C in an air atmosphere in a box furnace. After maintaining this temperature at 1400°C for 6 hours, the mixture was allowed to cool naturally to room temperature. The naturally cooled sample was then ground uniformly in an agate mortar to obtain the product with the chemical formula Ca2ScGa 2.97 Cr 0.03 Sn2O 12 Ultra-wideband near-infrared luminescent materials.

[0054] Example 2

[0055] This embodiment provides Ca2ScGa 2.94 Cr 0.06 Sn2O 12 The preparation method (i.e., x = 0.02, y = 0).

[0056] To prepare 2 mmol of the target product, 0.4004 g of CaCO3, 0.1379 g of Sc2O3, 0.5511 g of Ga2O3, 0.6028 g of SnO2, and 0.0091 g of Cr2O3 were weighed according to stoichiometric ratios, with a total mass of 1.7013 g for the mixed compound. The mixture was then ground in an agate mortar for 30 minutes until homogeneous. The resulting mixture was transferred to an alumina crucible and heated to 1400°C in an air atmosphere in a box furnace. After maintaining this temperature at 1400°C for 6 hours, the mixture was allowed to cool naturally to room temperature. The naturally cooled sample was then ground uniformly in an agate mortar to obtain the product with the chemical formula Ca2ScGa 2.94 Cr 0.06 Sn2O 12 Ultra-wideband near-infrared luminescent materials.

[0057] Example 3

[0058] This embodiment provides Ca2ScGa 2.91 Cr 0.09 Sn2O 12 The preparation method (i.e., x = 0.03, y = 0).

[0059] To prepare 2 mmol of the target product, 0.4004 g of CaCO3, 0.1379 g of Sc2O3, 0.5455 g of Ga2O3, 0.6028 g of SnO2, and 0.0137 g of Cr2O3 were weighed according to stoichiometric ratios, with a total mass of 1.7003 g for the mixed compound. The mixture was then ground in an agate mortar for 30 minutes until homogeneous. The resulting mixture was transferred to an alumina crucible and heated to 1400°C in an air atmosphere in a box furnace. After maintaining this temperature at 1400°C for 6 hours, the mixture was allowed to cool naturally to room temperature. The naturally cooled sample was then ground uniformly in an agate mortar to obtain the product with the chemical formula Ca2ScGa 2.91 Cr 0.09 Sn2O 12 Ultra-wideband near-infrared luminescent materials.

[0060] Example 4

[0061] This embodiment provides Ca2ScGa 2.85 Cr 0.15 Sn2O 12 The preparation method (i.e., x = 0.05, y = 0).

[0062] To prepare 2 mmol of the target product, 0.4004 g of CaCO3, 0.1379 g of Sc2O3, 0.5342 g of Ga2O3, 0.6028 g of SnO2, and 0.0228 g of Cr2O3 were weighed according to stoichiometric ratios, with a total mass of 1.6981 g for the mixed compound. The mixture was then ground in an agate mortar for 30 minutes until homogeneous. The resulting mixture was transferred to an alumina crucible and heated to 1400°C in an air atmosphere in a box furnace. After maintaining this temperature at 1400°C for 6 hours, the mixture was allowed to cool naturally to room temperature. The naturally cooled sample was then ground uniformly in an agate mortar to obtain the product with the chemical formula Ca2ScGa 2.85 Cr 0.15 Sn2O 12 Ultra-wideband near-infrared luminescent materials.

[0063] Example 5

[0064] This embodiment provides Ca2ScGa 2.79 Cr 0.21 Sn2O 12 The preparation method (i.e., x = 0.07, y = 0).

[0065] To prepare 2 mmol of the target product, 0.4004 g of CaCO3, 0.1379 g of Sc2O3, 0.5230 g of Ga2O3, 0.6028 g of SnO2, and 0.0319 g of Cr2O3 were weighed according to stoichiometric ratios, with a total mass of 1.6960 g for the mixed compound. The mixture was placed in an agate mortar and ground for 30 minutes until homogeneous. The resulting mixture was transferred to an alumina crucible and heated to 1400°C in an air atmosphere in a box furnace. After maintaining this temperature at 1400°C for 6 hours, the mixture was allowed to cool naturally to room temperature. The naturally cooled sample was then ground uniformly in an agate mortar to obtain the product with the chemical formula Ca2ScGa 2.85 Cr 0.15 Sn2O 12 Ultra-wideband near-infrared luminescent materials.

[0066] Figure 1 The X-ray powder diffraction (XRD) patterns of the ultrawideband near-infrared luminescent materials prepared in Comparative Example 1 and Preferred Examples 1-5 are shown in the figures. The diffraction peaks of Comparative Example 1 and Preferred Examples 1-5 are similar to those of Ca2ScGa3Sn2O. 12 The standard cards for the matrix corresponded one-to-one, indicating that the phase was a pure phase. Comparative Example 1 and Examples 1-5 were successfully prepared.

[0067] Figure 2 The excitation spectra of the ultrawideband near-infrared luminescent materials prepared in Comparative Example 1 and Preferred Examples 1-5 are shown. As shown in the figure, Comparative Example 1 and Preferred Examples 1-5 all exhibit strong absorption bands in the wavelength range of 400–700 nm, especially showing significant matching with the 450–480 nm band, confirming that this series of materials can be efficiently excited by commercial blue LED chips.

[0068] Figure 3 The emission spectra of the ultrawideband near-infrared luminescent materials prepared in Comparative Example 1 and Preferred Examples 1-5 of the present invention are shown. As the chromium ion doping concentration (x value) increases, the emission peak of the material gradually shifts from being dominated by the near-infrared I region (855 nm) in Comparative Example 1 (x = 0.005) to being dominated by the near-infrared II region (1300 nm) in Example 5 (e.g., Figure 4 As shown in Example 1), its full width at half maximum (FWHM) also significantly broadened from approximately 200 nm (Comparative Example 1) to 655 nm (Example 2). Furthermore, the material exhibited the strongest integrated luminescence intensity at x = 0.02 (Example 2). These results demonstrate that by adjusting the chromium ion doping concentration, not only can the emission spectrum be continuously tunable from the near-infrared I to II regions, and the emission bandwidth significantly broadened, but the overall luminescence intensity of the material can also be effectively optimized.

[0069] Example 6

[0070] This embodiment provides Ca2Sc 0.8 Y 0.2 Ga 2.94 Cr 0.06 Sn2O 12 The preparation method (i.e., x = 0.02, y = 0.2).

[0071] To prepare 2 mmol of the target product, 0.4004 g of CaCO3, 0.1103 g of Sc2O3, 0.5511 g of Ga2O3, 0.6028 g of SnO2, 0.0452 g of Y2O3, and 0.0091 g of Cr2O3 were weighed according to stoichiometric ratios, with a total mass of 1.7189 g for the mixed compound. The mixture was then ground in an agate mortar for 30 minutes until homogeneous. The resulting mixture was transferred to an alumina crucible and heated to 1400°C in an air atmosphere in a box furnace. After maintaining this temperature at 1400°C for 6 hours, the mixture was allowed to cool naturally to room temperature. The naturally cooled sample was then ground uniformly in an agate mortar to obtain the product with the chemical formula Ca2Sc. 0.8 Y 0.2 Ga 2.94 Cr 0.06 Sn2O 12 Ultra-wideband near-infrared luminescent materials.

[0072] Example 7

[0073] This embodiment provides Ca2Sc 0.6 Y 0.4 Ga 2.94 Cr 0.06 Sn2O 12 The preparation method (i.e., x = 0.02, y = 0.4).

[0074] To prepare 2 mmol of the target product, 0.4004 g of CaCO3, 0.0827 g of Sc2O3, 0.5511 g of Ga2O3, 0.6028 g of SnO2, 0.0903 g of Y2O3, and 0.0091 g of Cr2O3 were weighed according to stoichiometric ratios, with a total mass of 1.7364 g for the mixed compound. The mixture was then ground in an agate mortar for 30 minutes until homogeneous. The resulting mixture was transferred to an alumina crucible and heated to 1400°C in an air atmosphere in a box furnace. After maintaining this temperature at 1400°C for 6 hours, the mixture was allowed to cool naturally to room temperature. The naturally cooled sample was then ground uniformly in an agate mortar to obtain the product with the chemical formula Ca2Sc. 0.6 Y 0.4 Ga 2.94 Cr 0.06 Sn2O12 Ultra-wideband near-infrared luminescent materials.

[0075] Example 8

[0076] This embodiment provides Ca2Sc 0.4 Y 0.6 Ga 2.94 Cr 0.06 Sn2O 12 The preparation method (i.e., x = 0.02, y = 0.6).

[0077] To prepare 2 mmol of the target product, 0.4004 g of CaCO3, 0.0552 g of Sc2O3, 0.5511 g of Ga2O3, 0.6028 g of SnO2, 0.1355 g of Y2O3, and 0.0091 g of Cr2O3 were weighed according to stoichiometric ratios, with a total mass of 1.7541 g for the mixed compound. The mixture was then ground in an agate mortar for 30 minutes until homogeneous. The resulting mixture was transferred to an alumina crucible and heated to 1400°C in an air atmosphere in a box furnace. After maintaining this temperature at 1400°C for 6 hours, the mixture was allowed to cool naturally to room temperature. The naturally cooled sample was then ground uniformly in an agate mortar to obtain the product with the chemical formula Ca2Sc. 0.4 Y 0.6 Ga 2.94 Cr 0.06 Sn2O 12 Ultra-wideband near-infrared luminescent materials.

[0078] Example 9

[0079] This embodiment provides Ca2Sc 0.2 Y 0.8 Ga 2.94 Cr 0.06 Sn2O 12 The preparation method (i.e., x = 0.02, y = 0.8).

[0080] To prepare 2 mmol of the target product, 0.4004 g of CaCO3, 0.0276 g of Sc2O3, 0.5511 g of Ga2O3, 0.6028 g of SnO2, 0.1806 g of Y2O3, and 0.0091 g of Cr2O3 were weighed according to stoichiometric ratios, with a total mass of 1.7716 g for the mixed compound. The mixture was then ground in an agate mortar for 30 minutes until homogeneous. The resulting mixture was transferred to an alumina crucible and heated to 1400°C in an air atmosphere in a box furnace. After maintaining this temperature at 1400°C for 6 hours, the mixture was allowed to cool naturally to room temperature. The naturally cooled sample was then ground uniformly in an agate mortar to obtain the product with the chemical formula Ca2Sc. 0.2 Y0.8 Ga 2.94 Cr 0.06 Sn2O 12 Ultra-wideband near-infrared luminescent materials.

[0081] Example 10

[0082] This embodiment provides Ca2YGa 2.94 Cr 0.06 Sn2O 12 The preparation method (i.e., x = 0.02, y = 1).

[0083] To prepare 2 mmol of the target product, 0.4004 g of CaCO3, 0.5511 g of Ga2O3, 0.6028 g of SnO2, 0.2258 g of Y2O3, and 0.0091 g of Cr2O3 were weighed according to stoichiometric ratios, with a total mass of 1.7892 g for the mixed compound. The mixture was placed in an agate mortar and ground for 30 minutes until homogeneous. The resulting mixture was transferred to an alumina crucible and heated to 1400°C in an air atmosphere in a box furnace. After maintaining this temperature at 1400°C for 6 hours, the mixture was allowed to cool naturally to room temperature. The naturally cooled sample was then ground evenly in an agate mortar to obtain the product with the chemical formula Ca2YGa. 2.94 Cr 0.06 Sn2O 12 Ultra-wideband near-infrared luminescent materials.

[0084] Figure 5 The X-ray powder diffraction (XRD) patterns of the ultrawideband near-infrared luminescent materials prepared in Examples 2 and 6-10 are shown in the figures. The diffraction peaks of Examples 6-10 and Ca2ScGa3Sn2O can be observed in the figures. 12 The standard cards correspond one-to-one, indicating that the phase is a pure phase. Examples 6-10 were successfully prepared.

[0085] Figure 6 The normalized emission spectra of the ultrawideband near-infrared luminescent materials prepared in preferred embodiments 2 and 6-10 are shown. With the increase of Y... 3+ Replace Sc 3+ As the content (y value) gradually increases, the emission peak of the material can gradually shift from the near-infrared II region (Example 2, about 1300 nm) to the near-infrared I region (Example 10, about 855 nm), achieving effective and continuous control of the emission wavelength, and all samples maintain broadband near-infrared emission characteristics.

[0086] Figure 7The emission spectra (unnormalized) of preferred embodiment 2 and embodiments 6-10 are further illustrated. As shown in the figure, the emission intensity of the material in the near-infrared region I significantly increases with increasing y-value. Comparing embodiment 10 with embodiment 2 (fixed Cr doping concentration), the former shows an approximately 125-fold increase in emission peak intensity in the near-infrared region I, fully demonstrating that the emission intensity increases with increasing y-value. 3+ Replace Sc 3+ The component regulation strategy can not only achieve controllable adjustment of the near-infrared emission range, but also significantly enhance the luminescence efficiency of the material.

[0087] Figure 8 The graph shows the relationship between the relative integral intensity of the emission spectrum of the ultra-wideband near-infrared luminescent material prepared in Example 10 and temperature. It can be observed from the graph that the luminescence intensity of the material at 423 K is still 84% of that at room temperature, which proves that the material has excellent thermal stability.

[0088] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0089] The above embodiments should be understood as illustrative only and not as limiting the scope of protection of the present invention. After reading the description of the present invention, those skilled in the art can make various alterations or modifications to the present invention, and these equivalent changes and modifications also fall within the scope defined by the claims of the present invention.

Claims

1. A chromium ion-doped ultrawideband near-infrared fluorescent material, characterized in that, With Ca2ScGa3Sn2O 12 Using chromium ions as the activator and chromium as the matrix, its chemical formula is Ca2Sc 1-y Y y Ga 3-3x Sn2O 12 : xCr, where 0.003 ≤ x ≤ 0.10, 0.00 ≤ y ≤ 1.

00.

2. The luminescent material according to claim 1, characterized in that: The luminescent material includes Ca2ScGa 2.985 Cr 0.015 Sn2O 12 ,Ca2ScGa 2.97 Cr 0.03 Sn2O 12 ,Ca2ScGa 2.94 Cr 0.06 Sn2O 12 ,Ca2ScGa 2.91 Cr 0.09 Sn2O 12 ,Ca2ScGa 2.85 Cr 0.15 Sn2O 12 ,Ca2ScGa 2.79 Cr 0.21 Sn2O 12 Ca2Sc 0.8 Y 0.2 Ga 2.94 Cr 0.06 Sn2O 12 Ca2Sc 0.6 Y 0.4 Ga 2.94 Cr 0.06 Sn2O 12 Ca2Sc 0.4 Y 0.6 Ga 2.94 Cr 0.06 Sn2O 12 Ca2Sc 0.2 Y 0.8 Ga 2.94 Cr 0.06 Sn2O 12 ,Ca2YGa 2.94 Cr 0.06 Sn2O 12。 3. The luminescent material according to claim 1, characterized in that, The condition is 0.005 ≤ x ≤ 0.

07.

4. The luminescent material according to claim 3, characterized in that, The values ​​are x = 0.02 and y = 1.

00.

5. A method for preparing a chromium ion-doped ultrawideband near-infrared fluorescent material according to any one of claims 1-4, characterized in that, Includes the following steps: (1) According to the general formula Ca2Sc 1-y Y y Ga 3-3x Sn2O 12 Accurately weigh the raw materials according to the stoichiometric ratio of xCr (0.003 ≤ x ≤ 0.08, 0 ≤ y ≤ 1); (2) Grind the raw materials from step (1) in an agate mortar to obtain a uniformly mixed mixture of raw materials; (3) The raw material mixture from step (2) is calcined at high temperature in air atmosphere, and then naturally cooled and ground in air to obtain ultra-wideband near-infrared luminescent material.

6. The method for preparing chromium ion-doped ultrawideband near-infrared fluorescent material according to claim 5, characterized in that, The raw materials mentioned in step (1) are as follows: The Ca source used is one or more of calcium oxide, calcium carbonate, or calcium nitrate; The Y source used is one or more of yttrium oxide, yttrium carbonate, or yttrium nitrate; The Sc source used is one or more of scandium oxide, scandium carbonate, or scandium nitrate; The Ga source used is gallium oxide; The Sn source used is one or more of tin nitrate and tin oxide; The Cr source used is one or more of chromium nitrate, chromium oxide, or chromium chloride.

7. The preparation method according to claim 5, characterized in that, The raw material mixing method in step (2) is grinding, and the grinding method is wet grinding with alcohol, the alcohol content is 10-30 ml, and the grinding time is 30-60 minutes.

8. The preparation method according to claim 5, characterized in that, The calcination in step (3) involves placing the raw material mixture in an alumina crucible and using a tube furnace or box furnace. The calcination temperature is 1400-1700 ℃, the heating rate is 1-10℃ / min, and the holding time is 4-10 hours. The atmosphere is an air atmosphere.

9. The preparation method according to claim 5, characterized in that, The grinding step (3) involves grinding the sintered mixture in a mortar for 5-30 minutes to obtain a broadband infrared luminescent material.

10. A near-infrared LED device, characterized in that, It includes a commercial blue LED chip and a near-infrared luminescent material for LED packaging; the near-infrared luminescent material is the chromium ion single-doped ultrawideband near-infrared fluorescent material as described in any one of claims 1 to 4.

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