Infrared phosphor and preparation method thereof, and infrared light-emitting device

Abstract

The present invention provides an infrared phosphor and a preparation method thereof, and an infrared light-emitting device. The infrared phosphor of the present invention comprises a chemical formula of M a A b O c D d :xCr 3+ An inorganic compound, wherein 0.001≤x≤0.5, 0.8≤a≤1.2, 1.8≤b≤2.2, 3≤c≤5, 0.001≤d≤0.2, M is Mg, or at least one of Ca, Sr, Ba, and Zn and Mg, A is Ga, or at least one of Al, In, B, and Sc and Ga, and D is F or at least one of Cl, Br, and I. The infrared phosphor of the present invention has the advantages of high luminous intensity, high stability, and a long and adjustable emission peak wavelength. The emission spectrum is broadband, covering 700nm to 1100nm, and can be used in aspects such as food quality, anti-counterfeiting identification, and helping to determine the optimal harvest period of plants in the agricultural field.

Description

Technical Field

[0001] The present invention belongs to the field of infrared luminescence technology, and in particular relates to an infrared phosphor and a preparation method thereof, and an infrared luminescence device. Background Art

[0002] Due to the unique optical properties of infrared light, it has a wide range of applications in food testing, minimally invasive diagnosis, and spectral testing. Currently, near-infrared light sources mainly include tungsten lamps, infrared LEDs, and infrared lasers. However, they all have some defects. For example, tungsten lamps are inefficient, bulky, and have a short lifespan, and their spectrum contains a large amount of visible light. Infrared LEDs and infrared lasers have problems such as narrow bandwidth and narrow emission band coverage. At the same time, some infrared phosphors also have deficiencies such as low luminous quantum efficiency, which limits their application in some fields. For example, although the currently used infrared phosphors can emit near-infrared light, the half-width of the emission peak is generally less than 180nm, which cannot meet the application needs in food testing, anti-counterfeiting identification, and plant harvest period identification.

[0003] For example, there is already infrared phosphor MgGa 2-x O4:xCr 3+ , it emits near-infrared light with a peak wavelength of about 720nm, but the half-width of the emission peak is only about 94nm, and the luminescence efficiency is also low.

[0004] Therefore, based on the above technical problems, there is an urgent need to provide an infrared phosphor with a reasonable design that can solve the defects of the existing technology. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art and provides an infrared phosphor and a preparation method thereof.

[0006] One aspect of the present invention provides an infrared phosphor, wherein the infrared phosphor comprises a chemical formula of M a A b O c D d :xCr 3+ An inorganic compound, wherein 0.001≤x≤0.5, 0.8≤a≤1.2, 1.8≤b≤2.2, 3≤c≤5, 0.001≤d≤0.2, M is Mg, or at least one of Ca, Sr, Ba, and Zn and Mg, A is Ga, or at least one of Al, In, B, and Sc and Ga, and D is F, or at least one of Cl, Br, and I.

[0007] Furthermore, the infrared phosphor is composed of Mg 1+0.5d A 2-x O4F d :xCr 3+.

[0008] Furthermore, the infrared phosphor is composed of Mg 1+0.5d Ga 2-x O4F d :xCr 3+ Furthermore, the infrared phosphor is composed of Mg 1+0.5d (Ga,Sc) 2-x O4F d :xCr 3+ .

[0009] Furthermore, the infrared phosphor is composed of Mg 1+0.5d (Ga,In) 2-x O4F d :xCr 3+ .

[0010] Furthermore, the emission peak wavelength of the infrared phosphor is in the range of 840 nm to 940 nm, and the half-width of the emission peak is greater than 200 nm.

[0011] Furthermore, the emission spectrum of the infrared phosphor covers a wavelength range of 700 nm to 1100 nm.

[0012] Furthermore, the infrared phosphor can have an internal quantum efficiency of luminescence of more than 80%.

[0013] Another aspect of the present invention provides a method for preparing an infrared phosphor, wherein the infrared phosphor is as described above, and the specific steps include:

[0014] According to the chemical composition of the infrared phosphor M a A b O c D d :xCr 3+ A certain amount of M oxide, A oxide, Cr oxide, and an appropriate amount of halide are weighed in a preset stoichiometric ratio (0.001≤x≤0.5);

[0015] The weighed raw materials are mixed uniformly, and calcined at a temperature range of 1250° C. to 1500° C. under air atmosphere for 1 to 10 hours, at least once, to obtain a calcined product; wherein the calcination process adopts the following heating process: the first heating stage: the temperature range of 25° C. to 1000° C., the heating rate ≥ 10° C. / min; the second heating stage: the temperature range above 1000° C., the heating rate ≤ 5° C. / min;

[0016] The infrared phosphor is obtained by treating the calcination product.

[0017] Furthermore, the burning treatment time ranges from 4h to 6h.

[0018] Furthermore, the halide is at least one of alkali metal halide, alkaline earth metal halide, and ammonium halide.

[0019] Another aspect of the present invention provides an infrared light-emitting device, comprising an excitation source and an infrared fluorescent material, wherein the infrared fluorescent material is the infrared fluorescent powder described above.

[0020] The present invention provides an infrared phosphor, which contains a chemical formula of M a A b O c D d :xCr 3+ An inorganic compound, wherein 0.001≤x≤0.5, 0.8≤a≤1.2, 1.8≤b≤2.2, 3≤c≤5, 0.001≤d≤0.2, M is Mg, or at least one of Ca, Sr, Ba, and Zn and Mg, A is Ga, or at least one of Al, In, B, and Sc and Ga, and D is F, or at least one of Cl, Br, and I. The infrared phosphor of the present invention has a long and adjustable emission peak wavelength and a broadband emission spectrum covering 700nm to 1100nm. It has advantages such as high luminous intensity, high stability, and adjustable luminescence. The preparation process is simple, easy to operate and control, highly safe, low cost, and pollution-free. It can be used in the manufacture of infrared spectrum detection equipment and can be used in aspects such as food quality (calorie content, nutritional content, agricultural residues, etc.), anti-counterfeiting identification, and helping to confirm the optimal harvest period of plants in the agricultural field. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is an X-ray diffraction pattern of the phosphor according to one embodiment of the present invention;

[0022] Figure 2 This is a flowchart of the preparation process of infrared phosphor according to another embodiment of the present invention;

[0023] Figure 3 This is an emission spectrum diagram of an infrared phosphor according to another embodiment of the present invention;

[0024] Figure 4 This is an emission spectrum diagram of an infrared phosphor according to another embodiment of the present invention;

[0025] Figure 5 This is an emission spectrum diagram of an infrared phosphor according to another embodiment of the present invention;

[0026] Figure 5 This is an emission spectrum diagram of an infrared phosphor according to another embodiment of the present invention;

[0027] Figure 6This is an emission spectrum diagram of an infrared phosphor according to another embodiment of the present invention;

[0028] Figure 7 This is an emission spectrum diagram of an infrared phosphor according to another embodiment of the present invention;

[0029] Figure 8 This is an emission spectrum of the infrared phosphor of Comparative Example 1 of the present invention;

[0030] Figure 9 This is an emission spectrum diagram of an infrared phosphor according to another embodiment of the present invention;

[0031] Figure 10 FIG. 4 is an emission spectrum diagram of an infrared phosphor according to another embodiment of the present invention. DETAILED DESCRIPTION

[0032] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0033] One aspect of an embodiment of the present invention provides an infrared phosphor, wherein the infrared phosphor comprises a chemical formula of M a A b O c D d :xCr 3+ An inorganic compound, wherein 0.001≤x≤0.5, 0.8≤a≤1.2, 1.8≤b≤2.2, 3≤c≤5, 0.001≤d≤0.2, M is Mg, or at least one of Ca, Sr, Ba, and Zn and Mg, A is Ga, or at least one of Al, In, B, and Sc and Ga, and D is F, or at least one of Cl, Br, and I.

[0034] The infrared phosphor of this embodiment is Cr 3+ The ions are the luminescence centers, and by adjusting the doping amounts of different Cr, the obtained infrared phosphor has a long and adjustable emission peak wavelength, showing long-wave and ultra-wideband emission in the infrared region.

[0035] It should be noted that the infrared phosphor M of this embodiment a A b O c D d :xCr 3+The M in the formula ( ) can consist solely of Mg, or a portion of the Mg element can be replaced by one or more of Ca, Sr, Ba, and Zn. Similarly, A can consist solely of Ga, or a portion of the Ga element can be replaced by one or more of Al, In, B, and Sc. Similarly, D can consist solely of F, or a portion of the F element can be replaced by one or more of Cl, Br, and I.

[0036] It should be understood that when M includes Ba or Sr, or A includes In or Sc, the solid solution unit cell formed expands and its radius increases, causing the infrared phosphor emission peak to red-shift and the peak emission wavelength to lengthen. When M includes Ca or Zn, or A includes B or Al, the solid solution unit cell formed shrinks and its radius decreases, causing the infrared phosphor emission peak to blue-shift and the peak emission wavelength to shorten. In other words, by doping with the above-mentioned different elements, the peak emission wavelength range of the infrared phosphor of this embodiment can be further adjusted.

[0037] Specifically, the infrared phosphor of this embodiment is composed of Mg 1+0.5d A 2-x O4F d :xCr 3+ , the value range of x is 0.001≤x≤0.5.

[0038] As a further preferred embodiment of the present invention, the infrared phosphor of this embodiment is composed of Mg 1+0.5d Ga 2- x O4F d :xCr 3+ The phosphor with this chemical composition not only has a longer peak wavelength and a wider emission peak half-width, but also has very excellent infrared light emission efficiency.

[0039] As a further preferred embodiment of the present invention, the composition of the infrared phosphor of this embodiment is Mg 1+0.5d (Ga,Sc) 2-x O4F d :xCr 3+ Mg 1+0.5d (Ga,Sc) 2-x O4F d :xCr 3+ With Mg 1+0.5d Ga 2-x O4F d :xCr 3+ Compared with , it can further broaden the half-width of its emission peak.

[0040] As a further preferred embodiment of the present invention, the composition of the infrared phosphor of this embodiment is Mg 1+0.5d (Ga,In)2-x O4F d :xCr 3+ Mg 1+0.5d (Ga,In) 2-x O4F d :xCr 3+ With Mg 1+0.5d Ga 2-x O4F d :xCr 3+ Compared with Mg 1+0.5d (Ga,Sc) 2-x O4F d :xCr 3+ Compared with , it can have better quantum efficiency.

[0041] Furthermore, the emission spectrum of the infrared phosphor of this embodiment covers a wavelength range of 700 nm to 1100 nm. The infrared phosphor of the present invention has a long and adjustable emission peak wavelength, a wide half-peak width, and a wide range of applications.

[0042] Furthermore, the infrared phosphor of this embodiment can have an internal quantum efficiency of luminescence of more than 80%.

[0043] The infrared phosphor provided in this embodiment has a long and adjustable emission peak wavelength, a wide emission peak half-maximum, and a spectrum covering 700nm to 1100nm. It has the advantages of high luminous intensity, high stability, and adjustable luminescence. Its preparation process is simple, easy to operate and control, highly safe, low-cost, and pollution-free. It can be used in the manufacture of infrared spectroscopy detection equipment and can be used in aspects such as food quality (calorie content, nutritional content, agricultural residues, etc.), anti-counterfeiting identification, and helping to confirm the optimal harvest period of plants in the agricultural field.

[0044] like Figure 2 As shown, another aspect of the present invention provides a method S100 for preparing the infrared phosphor described above, which specifically includes the following steps S110 to S130:

[0045] S110, according to the chemical composition M of the infrared phosphor a A b O c D d :xCr 3+ A certain amount of M oxide, A oxide, Cr oxide, and an appropriate amount of halide are weighed in a preset stoichiometric ratio (0.001≤x≤0.5);

[0046] It should be noted that according to the chemical formula of infrared phosphor (M a A b O c D d :xCr3+ ), the oxide of M in this embodiment can be selected from Mg, or one or more of the four elements Ca, Sr, Ba, and Zn, and Mg. And, the oxide of A can be selected from Ga, or one or more of the four elements Al, In, B, and Sc, and Ga. That is, the Mg oxide included in the oxide of M can be partially replaced by the oxide of at least one of the above four elements, and the Ga oxide in the oxide of A can be partially replaced by the oxide of at least one of the above four elements. D is F, or at least one of the three elements Cl, Br, and I.

[0047] It should be further explained that an appropriate amount of halide may be added to the weighed oxides for mixing, which is more conducive to the burning treatment in step S120.

[0048] It should be noted that the halide of this embodiment can be one or both of alkali metal halide, ammonium halide or alkaline earth metal halide, without specific limitation, for example, ammonium chloride, magnesium fluoride, lithium fluoride or ammonium fluoride.

[0049] S120. Mix the weighed raw materials evenly, and calcine them in an air atmosphere at a temperature range of 1250°C to 1500°C for 1 hour to 10 hours, at least once, to obtain a calcined product; wherein, the calcination treatment adopts the following heating process: the first heating stage: the temperature range of 25°C to 1000°C, the heating rate ≥10°C / min; the second heating stage: the temperature range above 1000°C, the heating rate ≤5°C / min.

[0050] Specifically, the symmetrically taken oxide raw materials and halide are mixed evenly and subjected to a calcination treatment, wherein the calcination temperature is increased using the above-mentioned first and second temperature increasing stages, and when the temperature reaches the preset calcination temperature, the calcination treatment is carried out for 1 hour to 10 hours.

[0051] In other embodiments, the above-mentioned burning treatment time range may also be preferably 4 hours to 6 hours.

[0052] It should be understood that the above-mentioned burning process can be performed once or multiple times to further improve the brightness. When the burning process is performed multiple times, after the first burning process using the above-mentioned process, the burning product needs to be ground and sieved, and the treated burning product is then burned for the second time.

[0053] S130, treating the calcination product to obtain infrared phosphor.

[0054] Specifically, the calcined product is ground into powder, passed through a 200-mesh sieve, washed 1 to 3 times, centrifuged, and then the precipitate is dried at 60° C. to 80° C. to obtain the infrared phosphor.

[0055] The preparation method of this embodiment is simple, easy to operate, low in cost, pollution-free, and suitable for industrial batch production.

[0056] Another aspect of the present invention provides an infrared light-emitting device, comprising an excitation source and an infrared fluorescent material, wherein the infrared fluorescent material is the infrared fluorescent powder described above.

[0057] It should be noted that this embodiment does not specifically limit the excitation source. For example, an LED chip may be used.

[0058] The preparation method of infrared phosphor and the corresponding emission spectrum will be further explained below with reference to several specific examples.

[0059] Example 1

[0060] The preparation method of infrared phosphor in this example, the chemical formula of the phosphor is Mg 1.005 Ga 1.995 O4F 0.01 :0.005Cr, the preparation method comprises the following steps:

[0061] S1. According to the stoichiometric ratios of the elements in the above chemical formula, accurately weigh the raw materials MgO 1 mol, Cr2O3 0.0025 mol, Ga2O3 0.9975 mol, and MgF2 0.005 mol.

[0062] S2. After thoroughly mixing the weighed raw materials, place them in a crucible and place them in an electric furnace for sintering in an air atmosphere. The heating process is as follows: first heating stage: 25°C to 1000°C, heating rate 10°C / min; second heating stage: above 1000°C, heating rate 5°C / min. When the temperature reaches 1250°C, sinter for 10 hours, then cool to room temperature in the furnace to obtain a sintered product.

[0063] S3, the calcined product was fully ground into powder, passed through a 200 mesh sieve, washed with deionized water three times, and dried at 60 ° C to obtain the chemical formula Mg 1.005 Ga 1.995 O4F 0.01 :0.005Cr infrared phosphor material.

[0064] The emission spectrum of the infrared phosphor of this embodiment is as follows: Figure 3 As shown in Table 1, the wavelength of the emission spectrum peak is 840nm, the emission peak half-width is 205nm, and the internal quantum efficiency is 82%.

[0065] Example 2

[0066] The preparation method of infrared phosphor in this example, the chemical formula of the phosphor is Mg 1.03 Ga 1.95 O4F 0.06 :0.05Cr, the preparation method comprises the following steps:

[0067] S1. According to the stoichiometric ratios of the elements in the above chemical formula, accurately weigh the raw materials MgO 1 mol, Cr2O3 0.025 mol, Ga2O3 0.975 mol, and MgF2 0.03 mol.

[0068] S2. After thoroughly mixing the weighed raw materials, place them in a crucible and place them in an electric furnace for sintering in an air atmosphere. The heating process is as follows: first heating stage: 25°C to 1000°C, heating rate 12°C / min; second heating stage: above 1000°C, heating rate 4°C / min. When the temperature reaches 1500°C, sinter for 1 hour, then cool to room temperature in the furnace to obtain a sintered product.

[0069] S3, the calcined product was fully ground into powder, passed through a 200 mesh sieve, washed with deionized water three times, and dried at 60 ° C to obtain the chemical formula Mg 1.03 Ga 1.95 O4F 0.06 :0.05Cr infrared phosphor material.

[0070] The emission spectrum of the infrared phosphor of this embodiment is as follows: Figure 4 As shown in Table 1, the wavelength of the emission spectrum peak is 860 nm, the emission peak half-width is 212 nm, and the internal quantum efficiency is 81.2%.

[0071] Example 3

[0072] The preparation method of infrared phosphor in this example, the chemical formula of the phosphor is Mg 1.05 Ga 1.93 O4F 0.1 :0.07Cr, the preparation method comprises the following steps:

[0073] S1. According to the stoichiometric ratios of the elements in the above chemical formula, accurately weigh the raw materials MgO 1 mol, Cr2O3 0.035 mol, Ga2O3 0.965 mol, and MgF2 0.05 mol.

[0074] S2. After thoroughly mixing the weighed raw materials, place them in a crucible and place them in an electric furnace for sintering in an air atmosphere. The heating process is as follows: first heating stage: 25°C to 1000°C, heating rate 15°C / min; second heating stage: above 1000°C, heating rate 3°C / min. When the temperature reaches 1400°C, sinter for 4 hours, then cool to room temperature in the furnace to obtain a sintered product.

[0075] S3, the calcined product was fully ground into powder, passed through a 200 mesh sieve, washed with deionized water three times, and dried at 60 ° C to obtain the chemical formula Mg 1.05 Ga 1.93 O4F 0.1 :0.07Cr infrared phosphor material.

[0076] The emission spectrum of the infrared phosphor of this embodiment is as follows: Figure 5 As shown in Table 1, the wavelength of the emission spectrum peak is 870 nm, the emission peak half-width is 216 nm, and the internal quantum efficiency is 80.5%.

[0077] Example 4

[0078] The preparation method of infrared phosphor in this example, the chemical formula of the phosphor is Mg 1.1 Ga 1.8 O4F 0.2 :0.2Cr, the preparation method comprises the following steps:

[0079] S1. According to the stoichiometric ratios of the elements in the above chemical formula, accurately weigh the raw materials MgO 1 mol, Cr2O3 0.1 mol, Ga2O3 0.9 mol, and MgF2 0.1 mol.

[0080] S2. After thoroughly mixing the weighed raw materials, place them in a crucible and place them in an electric furnace for sintering in an air atmosphere. The heating process is as follows: first heating stage: 25°C to 1000°C, heating rate 12°C / min; second heating stage: above 1000°C, heating rate 4°C / min. When the temperature reaches 1300°C, sinter for 6 hours, then cool to room temperature in the furnace to obtain a sintered product.

[0081] S3, the calcined product was fully ground into powder, passed through a 200 mesh sieve, washed with deionized water three times, and dried at 60 ° C to obtain the chemical formula Mg 1.1 Ga 1.8 O4F 0.2 :0.2Cr infrared phosphor material.

[0082] The emission spectrum of the infrared phosphor of this embodiment is as follows: Figure 6 As shown in Table 1, the wavelength of the emission spectrum peak is 910 nm, the emission peak half-width is 230 nm, and the internal quantum efficiency is 55%.

[0083] Example 5

[0084] The preparation method of infrared phosphor in this example, the chemical formula of the phosphor is Mg 1.25 Ga 1.5 O4Cl 0.5 :0.5Cr, the preparation method comprises the following steps:

[0085] S1. According to the stoichiometric ratios of the elements in the above chemical formula, accurately weigh the raw materials MgO 1 mol, Cr2O3 0.25 mol, Ga2O3 0.75 mol, and MgCl2 0.25 mol.

[0086] S2. After thoroughly mixing the weighed raw materials, place them in a crucible and place them in an electric furnace for sintering in an air atmosphere. The heating process is as follows: first heating stage: 25°C to 1000°C, heating rate 11°C / min; second heating stage: above 1000°C, heating rate 2°C / min. When the temperature reaches 1450°C, sinter for 3 hours, then cool to room temperature in the furnace to obtain a sintered product.

[0087] S3, the calcined product was fully ground into powder, passed through a 200 mesh sieve, washed with deionized water three times, and dried at 60 ° C to obtain the chemical formula Mg 1.25 Ga 1.5 O4Cl 0.5 :0.5Cr infrared phosphor material.

[0088] The emission spectrum of the infrared phosphor of this embodiment is as follows: Figure 7 As shown in Table 1, the wavelength of the emission spectrum peak is 940 nm, the emission peak half-width is 235 nm, and the internal quantum efficiency is 48.5%.

[0089] Comparative Example 1

[0090] The preparation method of the infrared phosphor in the comparative example, the chemical formula of the phosphor is MgGa 1.95 O4:0.05Cr, the preparation method comprises the following steps:

[0091] 1. According to the stoichiometric ratio of each element in the above chemical formula, accurately weigh the raw materials MgO 1 mol, Cr2O3 0.025 mol, and Ga2O3 0.975 mol.

[0092] 2. After fully mixing the weighed raw materials, put them into a crucible and place them in an electric furnace for sintering in an air atmosphere. The temperature was set in the range of 25°C to 1000°C at a heating rate of 10°C / min; in the temperature range above 1000°C, the heating rate was 5°C / min; the mixture was calcined at 1300°C for 6 hours, and then cooled to room temperature to obtain a calcined product.

[0093] S3, the calcined product was fully ground into powder, passed through a 200 mesh sieve, washed with deionized water three times, and dried at 60 ° C to obtain the MgGa 1.95 O4:0.05Cr infrared phosphor material.

[0094] The emission spectrum of the infrared phosphor of this embodiment is as follows: Figure 8 As shown in Table 1, the wavelength of the emission spectrum peak is 720 nm, the emission peak half-width is 94 nm, and the internal quantum efficiency is 35%.

[0095] Example 6

[0096] The preparation method of infrared phosphor in this example, the chemical formula of the phosphor is Mg 1.025 Ga 1.73 In 0.2 O4F 0.05 :0.07Cr, the preparation method comprises the following steps:

[0097] S1. According to the stoichiometric ratios of the elements in the above chemical formula, accurately weigh the raw materials MgO 1 mol, Cr2O3 0.035 mol, In2O3 0.1 mol, Ga2O3 0.865 mol, and MgF2 0.025 mol.

[0098] S2. The weighed raw materials are thoroughly mixed, placed in a crucible, and sintered in an electric furnace in an air atmosphere. The heating process is as follows: the first heating stage is in the temperature range of 25°C to 1000°C, with a heating rate of 10°C / min; the second heating stage is in the temperature range above 1000°C, with a heating rate of 5°C / min. When the temperature reaches 1250°C, the crucible is sintered for 10 hours, and then cooled to room temperature in the furnace to obtain a sintered product.

[0099] S3, the calcined product was fully ground into powder, passed through a 200 mesh sieve, washed with deionized water three times, and dried at 60 ° C to obtain the chemical formula Mg 1.025 Ga 1.73 In 0.2 O4F 0.05 :0.07Cr infrared phosphor material.

[0100] The emission spectrum of the infrared phosphor of this embodiment is as follows: Figure 9As shown in Table 1, the wavelength of the emission spectrum peak is 860 nm, the emission peak half-width is 260 nm, and the internal quantum efficiency is 47.8%.

[0101] Example 7

[0102] The preparation method of infrared phosphor in this example, the chemical formula of the phosphor is Mg 1.04 Ga 1.72 Sc 0.2 O4F 0.08 :0.08Cr, the preparation method comprises the following steps:

[0103] S1. According to the stoichiometric ratios of the elements in the above chemical formula, accurately weigh the raw materials MgO 1 mol, Cr2O3 0.04 mol, Sc2O3 0.1 mol, Ga2O3 0.86 mol, and MgF2 0.04 mol.

[0104] S2. After fully mixing the weighed raw materials, put them into a crucible and place them in an electric furnace for sintering in air atmosphere. The heating process is set as follows: the first heating stage: 25℃~1000℃ temperature range, heating rate 10℃ / min; the second heating stage: above 1000℃ temperature range, heating rate 5℃ / min. When the temperature reaches 1250℃, the temperature is heated to 1000℃ and the heating rate is 5℃ / min.

[0105] ℃ for 10 h, and then cooled to room temperature to obtain the calcined product.

[0106] S3, the calcined product was fully ground into powder, passed through a 200 mesh sieve, washed with deionized water three times, and dried at 60 ° C to obtain the chemical formula Mg 1.04 Ga 1.72 Sc 0.2 O4F 0.08 :0.08Cr infrared phosphor material.

[0107] The emission spectrum of the infrared phosphor of this embodiment is as follows: Figure 10 As shown in Table 1, the wavelength of the emission spectrum peak is 860 nm, the emission peak half-width is 240 nm, and the internal quantum efficiency is 49.8%.

[0108] Table 1: Comparison of parameters of infrared phosphors in some examples and comparative examples

[0109]

[0110] In summary, Table 1 compares the relevant parameters of the infrared phosphors synthesized in some examples of the present invention and those synthesized in comparative examples. As can be seen, compared with Comparative Example 1, the infrared phosphors obtained in Examples 1-5 of the present invention exhibit longer emission peak wavelengths, wider emission peak half-widths, and higher infrared light emission efficiencies.

[0111] The infrared phosphor obtained in Example 6 of the present invention contains In. Compared with Examples 1 to 5, the luminescence spectrum thereof has a wider emission peak half-width.

[0112] The infrared phosphor obtained in Example 7 of the present invention contains Sc. Compared with Examples 1 to 5, the luminescence spectrum thereof has a wider emission peak half-width.

[0113] At the same time, the infrared phosphor of the present invention has a higher internal quantum efficiency of luminescence than the infrared phosphor of the comparative example, indicating that the luminescence efficiency of the infrared phosphor of the present invention is also more excellent.

[0114] It will be understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present invention, and the present invention is not limited thereto. Those skilled in the art will appreciate that various modifications and improvements can be made without departing from the spirit and substance of the present invention, and such modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. An infrared phosphor, characterized in that: The chemical formula of the infrared phosphor is Mg 1+0.5d Ga 2-x O4F d :xCr 3+ , wherein 0.001≤x≤0.5, 0.001≤d≤0.1, the emission peak half-width of the infrared phosphor is greater than 200 nm, and the luminescence internal quantum efficiency of the infrared phosphor can reach more than 80%.

2. The infrared phosphor according to claim 1, characterized in that: The emission peak wavelength of the infrared phosphor is in the range of 840nm to 940nm.

3. The infrared phosphor according to claim 1, characterized in that: The emission spectrum of the infrared phosphor covers a wavelength range of 700nm to 1100nm.

4. A method for preparing infrared phosphor, characterized in that: The infrared phosphor according to any one of claims 1 to 3, wherein the specific steps include: According to the chemical composition of the infrared phosphor Mg 1+0.5d Ga 2-x O4F d :xCr 3+ A certain amount of Mg oxide, Ga oxide, Cr oxide, and magnesium fluoride, lithium fluoride or ammonium fluoride is weighed in a preset stoichiometric ratio; wherein 0.001≤x≤0.5, 0.001≤d≤0.1; The weighed raw materials are mixed uniformly, and calcined at a temperature range of 1250°C to 1500°C under air atmosphere for 1 hour to 10 hours, at least once, to obtain a calcined product; wherein the calcination process adopts the following heating process: the first heating stage: the temperature range of 25°C to 1000°C, the heating rate of ≥10°C / min; the second heating stage: the temperature range above 1000°C, the heating rate of ≤5°C / min; The infrared phosphor is obtained by treating the calcination product.

5. The preparation method according to claim 4, characterized in that The burning treatment time ranges from 4h to 6h.

6. An infrared light emitting device, characterized in that: The invention comprises an excitation source and an infrared fluorescent material, wherein the infrared fluorescent material comprises the infrared fluorescent powder according to any one of claims 1 to 3.

Images