A Cr 3+ Doped fluorosulfate host deep red luminescent material, preparation and application thereof

Abstract

The application relates to a Cr 3+ A novel fluorosulfate matrix deep red luminescent material doped with Cr 2(1‑a) A 2a Al (1‑b) B b SO4F3:xCr 3+ , 0<=a<=1, 0<=b<=0.5, A is at least one of first main group elements or monovalent Ag, Cu and Au, B includes one of trivalent ions of Ga, In, TI and Sc, and the luminescent center is Cr 3+ . A preparation method of the luminescent material is as follows: raw materials are weighed according to stoichiometric ratios of substances, are ground to mix uniformly, are pre-sintered, are ground again, are calcined again after mixing more uniformly, and are obtained after centrifugation, drying and sieving. Compared with the prior art, the Cr 3+ doped novel fluorosulfate matrix deep red luminescent material prepared by the application has simple synthesis process, and in addition, hydrogen fluoride harmful to human beings and environment or toxic and easily-decomposed ammonium fluoride is not needed to provide a fluorine source in the synthesis process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of deep red fluorescent material preparation, in particular to a Cr 3+ doped novel fluorosulfate matrix deep red luminescent material and its preparation and application. BACKGROUND

[0002] With the development of technology and the expansion of application, deep red fluorescent materials have shown important application value in many fields, such as plant lighting growth, LED lighting, display technology, biomedical, etc. In particular, in the field of plant lighting, deep red light has a significant promoting effect on plant growth and photosynthesis. So far, red light emitting fluorescent materials are mainly based on rare earth or transition metal ion activated luminescent materials, such as Eu 2+ , Eu 3+ , Sm 3+ , Pr 3+ and Mn 4+ activated fluorescent materials. However, their disadvantages are also obvious, such as the high price of rare earth ion raw materials, the use of hydrogen fluoride acid or toxic and easily decomposed ammonium fluoride for the synthesis of fluoride fluorescent materials, which are harmful to human body and environment, the deep red light emission of rare earth ions or transition metal Mn 4+ is not obvious, which limits their application in plant growth lighting. The deep red light required for plant lighting growth is between 650-800nm, and the spectral purity of deep red light needs to be high to reduce unnecessary effects of other light sources. In contrast, transition metal Cr 3+ doped fluorescent materials that can emit deep red light are expected to be applied in LEDs due to their non-toxic, inexpensive and high spectral purity of deep red light properties. Among them, Cr 3+ doped fluorescent materials have strong red light (600-650nm) or deep red light (650-800nm) emission. In recent years, Cr 3+ doped fluorescent materials have been reported in the literature for application in plant lighting in the deep red light band, such as MgAl2O4:Cr 3+ (Opt. Mater., 2022. 12(8): 2942-2953), SrMgAl 10 O 17 :Cr 3+ (J. Lumin., 2024. 270: 120553), LiMgAlF6:Cr 3+ (J. Lumin., 2023. 263: 120095), etc. However, so far, most of them are oxides and fluorides. Oxide as matrix material has simple preparation process and low energy consumption, and fluoride as matrix material has the advantages of high efficiency and high concentration doping to achieve high brightness emission, etc.

[0003] A new fluoroalumosulfate mineral K2[(AlF3)SO4] was reported in 2008 from a volcanic crater in Italy (Can. Mineral., 2008. 46(3): 693-700.). There are only four examples of fluoroalumosulfate compounds known to date, i.e., the natural minerals A2AlSO4F3(A = K, NH4) and the synthetic fluoroalumosulfate Li4MA1(SO4)2F4(M = Rb, Cs), Na2AlSO4F3(Inorg. Chem., 2024. 63(3): 1674-1681), which were statistically analyzed and analyzed in the reasonable combination of [AlO2F4] and [SO4] groups. Among them, the artificial synthesis process of K2AlSO4F3 has not been reported so far. K2AlSO4F3 crystallizes in the orthorhombic space group Pbcn, with unit cell parameters a = 10.810 Å, b = 8.336 Å, c = 6.822 Å; α = β = γ = 90°. Transition metal ions Cr 3+ ions with electronic configuration 3d 3 , Cr 3+ ions depend on the crystal field environment. Fluorosulfate combines the characteristics of fluoride and sulfate, showing good chemical stability.

[0004] Therefore, it is particularly important to develop more efficient and stable new deep red fluorescent materials using fluorosulfate. SUMMARY

[0005] The purpose of the present application is to overcome the defects of the prior art and provide a new Cr 3+ doped fluorosulfate matrix deep red luminescent material and its preparation and application. The prepared Cr 3+ doped fluorosulfate matrix deep red luminescent material has a simple synthesis process, and in addition, it does not need to use hydrofluoric acid which is harmful to humans and the environment or toxic and easily decomposed ammonium fluoride to provide a fluorine source during the synthesis process.

[0006] The purpose of the present application can be achieved by the following technical solutions:

[0007] The present application provides a new Cr 3+ doped fluorosulfate matrix deep red luminescent material, which has the following chemical general formula: K 2(1-a) A 2a Al (1-b) B b SO4F3:xCr 3+ , 0≤a≤1, 0≤b≤0.5,

[0008] Wherein, 0.1at%≤x≤20at%, A is a Group 1 element or at least one of monovalent Ag, Cu, and Au, B includes one of trivalent ions of Ga, In, Ti, and Sc, and the luminescent center is Cr. 3+ .

[0009] The present invention also provides a Cr 3+ A method for preparing a novel doped fluorosulfate matrix deep red luminescent material includes the following steps:

[0010] S1: Weigh the raw materials according to the stoichiometric ratio of each substance required for the target product, add anhydrous ethanol and grind them to make them evenly mixed to obtain the precursor.

[0011] S2: The precursor is loaded into an alumina crucible and pre-sintered to remove moisture and obtain a pre-sintered sample.

[0012] S3: Take out the pre-sintered sample from S2, grind it again to make the mixture more uniform, and then put it back into the alumina crucible for calcination to obtain the target compound.

[0013] S4: The target compound prepared in S3 was ultrasonically vibrated in deionized water, centrifuged, dried, and sieved to obtain the desired Cr crystals. 3+ A novel doped fluorosulfate matrix deep red luminescent material.

[0014] Further, in S1, the raw materials include one or more of the following: compounds containing a first group element or monovalent Ag, Cu, Au, trivalent ionic compounds containing Ga, In, Ti, Sc, potassium-containing compounds, chromium-containing compounds, aluminum-containing compounds, sulfur-containing compounds, and fluorine-containing compounds.

[0015] Furthermore, the compound containing a Group 1 element or monovalent Ag, Cu, Au includes at least one of oxides, nitrates, carbonates, hydroxides, or sulfates containing a Group 1 element or monovalent Ag, Cu, Au;

[0016] The trivalent ionic compounds containing Ga, In, Ti, and Sc include at least one of oxides, nitrates, carbonates, hydroxides, or fluorides containing trivalent ions of Ga, In, Ti, and Sc.

[0017] The chromium-containing compound includes at least one of chromium oxide, chromium nitrate, chromium carbonate, or chromium fluoride.

[0018] The potassium-containing compound includes at least one of potassium carbonate, potassium nitrate, or potassium sulfate;

[0019] The aluminum-containing compound includes at least one of aluminum oxide, aluminum nitrate, aluminum hydroxide, or aluminum fluoride;

[0020] The sulfur-containing compound includes at least one of sulfuric acid, a sulfur-containing salt;

[0021] The fluorine-containing compound includes at least one of hydrofluoric acid, a fluorine-containing compound.

[0022] Further, in S2, the pre-sintering temperature is 300-550 DEG C, and the pre-sintering time is 1-10 hours.

[0023] Further, in S3, the calcining temperature is 600-800 DEG C, and the calcining time is 5-20 hours.

[0024] Further, in S2 and S3, the pre-sintering and calcining heating rates are both 4-6 DEG C / min.

[0025] Further, in S3, the grinding time is 0.5-1 hour.

[0026] Further, in S4, the drying temperature is 50-250 DEG C.

[0027] The application also provides a Cr 3+ The application of the doped novel fluorosulfate matrix deep red luminescent material as a fluorescent material in plant lighting growth, display technology, biomedicine, security and anti-counterfeiting, photoelectric detection and sensing fields.

[0028] Compared with the prior art, the application has the following advantages and beneficial effects:

[0029] 1. The Cr 3+ The doped novel fluorosulfate matrix deep red luminescent material has a simple synthesis process, and in addition, does not need to use hydrogen fluoride or toxic and easily decomposed ammonium fluoride to provide a fluorine source in the synthesis process.

[0030] 2. The application can replace part of the expensive K2SO4 with the low-cost Na2SO4, so that the cost is reduced, the luminescent intensity is not reduced but increased, and the application is more suitable for industrial production. + Part of the K+ + Ions are replaced with low-cost Na2SO4, so that the cost is reduced, the luminescent intensity is not reduced but increased, and the application is more suitable for industrial production.

[0031] 3. The application selects a fluorosulfate without hydrogen fluoride as a luminescent matrix, has a simple synthesis process, simple and safe operation, low equipment requirement, a wide source of raw materials, and is suitable for industrial production. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1X-ray diffraction pattern of the deep red light emitting material prepared in Example 1;

[0033] Figure 2 Diffuse reflection spectrum of the deep red light emitting material prepared in Example 1;

[0034] Figure 3 Emission spectrum of the deep red light emitting material prepared in Example 1;

[0035] Figure 4 Emission spectrum of the deep red light emitting material prepared in Example 1 and Example 8. DETAILED DESCRIPTION

[0036] The specific embodiments of the present application are described in detail below with reference to the accompanying drawings and specific examples. The embodiments are implemented on the premise of the scheme described in the present application, and detailed embodiments and specific operation processes are given, but the protection scope of the present application is not limited to the following examples.

[0037] The present application is further described below in conjunction with the accompanying drawings and specific examples. In the technical scheme, if the component model, material name, connection structure, preparation means, material, structure or component ratio and other features are not explicitly stated, they are considered as common technical features disclosed in the prior art.

[0038] The present application successfully synthesizes Cr 3+ A series of K2AlSO4F3 deep red fluorescent materials without hydrofluoric acid and the preparation and application thereof, the present application regulates the cation position on the basis of the original structure, the first main group elements such as Na, Rb, Cs or Cu, Ag, Au and other monovalent ions occupy the (A) position, Ga, In, TI, Sc and other trivalent ions occupy the (B) position, the present application replaces part of K ions with Na, Rb, Cs or Cu, Ag, Au ions, and part of Al ions with Ga, In, TI, Sc ions, and then realizes the doping of additional ions at the (A) position and the (B) position, and then regulates the luminescence spectrum of the synthesized material, uses low-cost raw materials, and has better performance. When no additional ions are doped, the chemical formula of the present application is: K2AlSO4F3:xCr 3+ , and the chemical formula after doping is: K 2(1-a) A 2a Al (1-b) B b SO4F3:xCr 3+ , 0≤a≤1, 0≤b≤0.5, wherein 0.1at%≤x≤20at%.

[0039] The present application successfully synthesizes Cr 3+ doped fluorescent material in a strong crystal field, and spin-forbidden 2E → 4 Narrow emission band of A2 transition. Narrow band emission in the deep red range has advantages such as promoting photosynthesis, promoting plant lateral growth and flowering, spectral purity, reducing energy waste, and precise control of light environment in plant lighting. These advantages make narrow band emission light sources widely used in modern agriculture and horticulture. A series of K2AlSO4F3:xCr3+ deep red fluorescent materials are successfully synthesized by using pure solid phase synthesis route without using hydrogen fluoride raw materials harmful to human and environment in the synthesis process, taking fluorosulfate K2AlSO4F3 as the matrix. 2(1-a) A 2a Al (1-b) B b SO4F3:xCr 3+ Deep red fluorescent material.

[0040] Example 1

[0041] This example provides a Cr 3+ doped novel fluorosulfate matrix deep red luminescent material, this example does not dope additional ions at (A) position and (B) position except Cr 3+ , the material is in powder form, and the molecular formula is as follows: K2Al 0.995 Cr 0.005 SO4F3.

[0042] The preparation method is as follows:

[0043] S1: According to the stoichiometric ratio of each substance calculated according to the molecular formula, take potassium sulfate, aluminum fluoride and chromium fluoride with purity of AR and above as raw materials, and the mass is 1.3490g, 0.6468g and 0.0042g respectively. Add appropriate amount of anhydrous ethanol in a agate mortar and grind uniformly to obtain a precursor;

[0044] S2: Grind the precursor in S1 in the agate mortar for 1 hour until it is uniformly ground, then load it into an alumina crucible, heat to 550℃ at a rate of 5℃ / min in air atmosphere, and sinter for 2 hours, then cool to room temperature with the furnace, and obtain a pre-sintered sample;

[0045] S3: Put the pre-sintered sample in S2 into a agate mortar and grind for 0.5 hours until it is uniformly ground, then load it into an alumina crucible again, heat to 700℃ at a rate of 5℃ / min in air atmosphere, and sinter for 10 hours, then cool to room temperature with the furnace, and take out the target product and grind it to a powder without particles;

[0046] S4: Add appropriate amount of deionized water to the target product ground in S3, ultrasonic oscillation for 30min, then put it in a centrifuge tube, centrifuge at a speed of 12000r / min for 20min, then dry at 100℃ and sieve, and obtain K2Al 0.995 Cr0.005 SO4F3 deep red luminescent material.

[0047] The obtained product K2AlSO4F3: 0.5 at% Cr 3+ The phase analysis was performed using X-ray powder diffraction analysis method, see Figure 1 Compared with the standard library of the target product, the sample powder diffraction peak intensity is high, and there is no obvious impurity, indicating that the obtained compound is a pure phase; Figure 2 The UV-visible diffuse reflectance spectrum of the sample is shown in the figure, and it can be seen from the figure that the sample has obvious absorption peaks in the 200-600nm waveband, and there is absorption in the ultraviolet and green light regions; Figure 3 The emission spectrum of the sample is shown in the figure, it can be seen that the sample can emit deep red light of 694nm under the excitation of 553nm, which is particularly close to the deep red light region of 700nm, and has a significant impact on the photosynthesis, morphological construction and physiological activity of plants, and the emission spectrum belongs to narrow-band emission; Figure 4 The emission spectrum of the deep red luminescent material samples prepared in Example 1 and Example 8 is shown in the figure, wherein Na is used to replace half of K, it can be seen that the cost of the prepared sample is reduced, and the luminescence intensity is still 1.6 times that of the non-substituted.

[0048] The deep red material prepared in this example shows narrow-band emission in the deep red region, and the luminescence waveband is located in the deep red waveband of 650-800nm, and the peak value is 694nm, which is well matched with the absorption peak of plant photosensitive pigment P FR , and is suitable for application in plant lighting.

[0049] Example 2

[0050] This example provides a new type of Cr 3+ doped fluorosulfate matrix deep red luminescent material, in addition to Cr 3+ , no additional ions are doped in (A) position and (B) position. The material is in powder form, and the molecular formula is as follows: K2Al 0.99 Cr 0.01 SO4F3.

[0051] The preparation method is as follows:

[0052] S1: According to the stoichiometric ratio of each substance, take potassium sulfate, aluminum fluoride and chromium fluoride with purity of AR and above as raw materials, and the mass is 1.3483g, 0.6433g and 0.0084g respectively. Add appropriate amount of anhydrous ethanol to the agate mortar, grind and mix uniformly to obtain the precursor;

[0053] S2: The precursor in S1 was ground in a agate mortar for 1 hour until it was ground uniformly, then it was loaded into an alumina crucible, and was heated to 500℃ at a rate of 5℃ / min under air atmosphere, and was sintered for 2 hours, then it was cooled to room temperature with the furnace, and a pre-sintered sample was obtained;

[0054] S3: The pre-sintered sample in S2 was placed in a agate mortar and was ground for 0.5 hours until it was ground uniformly, then it was loaded into an alumina crucible again, and was heated to 650℃ at a rate of 5℃ / min under air atmosphere, and was calcined for 10 hours, then it was cooled to room temperature with the furnace, and the obtained product was ground to a powder without a grainy feeling;

[0055] S4: The ground product in S3 was added to a proper amount of deionized water, and was ultrasonically vibrated for 30 minutes, then it was placed in a centrifuge tube, and was centrifuged at a speed of 11000r / min for 15 minutes, then it was dried at 100℃ and was sieved, and K2Al 0.99 Cr 0.01 SO4F3 deep red luminescent material.

[0056] Example 3

[0057] The present embodiment provides a Cr 3+ doped new fluorosulfate matrix deep red luminescent material, only doped with trivalent ion Ga 3+ The luminescent spectrum is regulated. That is, a=0, b=0.2; the material is in a powder state, and the molecular formula is as follows: K2Al 0.795 Ga 0.2 Cr 0.005 SO4F3.

[0058] The preparation method is as follows:

[0059] S1: According to the stoichiometric ratio of each substance, potassium sulfate, aluminum fluoride, gallium fluoride, and chromium fluoride with a purity of AR or above were used as raw materials, and the mass was 1.3058g, 0.5003g, 0.1899g, and 0.0041g respectively. The precursor was obtained by grinding the above-mentioned substances in a agate mortar with a proper amount of anhydrous ethanol until they were uniformly mixed;

[0060] S2: The precursor in S1 was ground in a agate mortar for 1 hour until it was ground uniformly, then it was loaded into an alumina crucible, and was heated to 500℃ at a rate of 5℃ / min under air atmosphere, and was sintered for 2 hours, then it was cooled to room temperature with the furnace, and a pre-sintered sample was obtained;

[0061] S3: The pre-sintered sample in S2 was placed in a agate mortar and was ground for 0.5 hours until it was ground uniformly, then it was loaded into an alumina crucible again, and was heated to 650℃ at a rate of 5℃ / min under air atmosphere, and was calcined for 10 hours, then it was cooled to room temperature with the furnace, and the obtained product was ground to a powder without a grainy feeling;

[0062] S4: The product after grinding in S3 is added with appropriate amount of deionized water and ultrasonic oscillation for 30 min, then placed in a centrifuge tube, centrifuged at 11000 r / min for 15 min, dried at 100 ℃ and sieved to obtain K2Al 0.795 Ga 0.2 Cr 0.005 SO4F3 deep red luminescent material.

[0063] Example 4

[0064] The embodiment provides a Cr 3+ The new fluorosulfate matrix deep red luminescent material is doped with only trivalent ion In 3+ The luminescence spectrum is regulated. That is, a=0 and b=0.05; the material is in powder form, and the molecular formula is as follows: K2Al 0.945 In 0.05 Cr 0.005 SO4F3.

[0065] The preparation method is as follows:

[0066] S1: According to the stoichiometric ratio of each substance, potassium sulfate, aluminum fluoride, indium fluoride and chromium fluoride with a purity of AR or above are used as raw materials, and the mass is 1.3264 g, 0.6041 g, 0.0654 g and 0.0041 g respectively. The precursor is obtained by grinding the mixed substances in a proper amount of anhydrous ethanol in a agate mortar.

[0067] S2: The precursor in S1 is ground in a agate mortar for 1 hour until it is uniformly ground, then loaded into an alumina crucible, heated to 500 ℃ at a rate of 5 ℃ / min in an air atmosphere, and heat treated and calcined for 2 hours, then cooled to room temperature with the furnace, to obtain a pre-sintered sample;

[0068] S3: The pre-sintered sample in S2 is placed in a agate mortar and ground for 0.5 hours until it is uniformly ground, then loaded into an alumina crucible again, heated to 650 ℃ at a rate of 5 ℃ / min in an air atmosphere, and heat treated and calcined for 10 hours, then cooled to room temperature with the furnace, and the obtained product is ground into a powder without particles;

[0069] S4: The product after grinding in S3 is added with appropriate amount of deionized water and ultrasonic oscillation for 30 min, then placed in a centrifuge tube, centrifuged at 11000 r / min for 15 min, dried at 100 ℃ and sieved to obtain K2Al 0.945 In 0.05 Cr 0.005 SO4F3 deep red luminescent material.

[0070] Example 5

[0071] The embodiment provides a Cr 3+ The doped novel fluorosulfate matrix deep red luminescent material is only doped with monovalent ions Cs + The luminescent spectrum is regulated. That is, a=0.05, b=0; the material is in a powder state, and the molecular formula is as follows: K 1.9 Cs 0.1 Al 0.995 Cr 0.005 SO4F3.

[0072] The preparation method is as follows:

[0073] S1: according to the stoichiometric ratio of each substance, taking potassium sulfate, cesium sulfate, aluminum fluoride and chromium fluoride with a purity of AR or above as raw materials, and the mass is 1.2366 g, 0.1352 g, 0.6242 g and 0.0041 g respectively; the precursor is obtained by grinding the mixture in a proper amount of anhydrous ethanol in a agate mortar;

[0074] S2: the precursor in S1 is ground in a agate mortar for 1 hour until uniform, then is loaded into an alumina crucible, and is heated to 500 DEG C at a rate of 5 DEG C / min in an air atmosphere, and is kept and sintered for 2 hours, and then is cooled to room temperature with the furnace, to obtain a presintered sample;

[0075] S3: the presintered sample is placed in a agate mortar and ground for 0.5 hours until uniform, then is loaded into an alumina crucible again, and is heated to 650 DEG C at a rate of 5 DEG C / min in an air atmosphere, and is kept and calcined for 10 hours, and then is cooled to room temperature with the furnace, and the obtained product is ground into a powder without particles;

[0076] S4: the product ground in S3 is added into a proper amount of deionized water, and is ultrasonically oscillated for 30 min, and then is placed in a centrifuge tube, and is centrifuged at a speed of 11000 r / min for 15 min, and then is dried at 100 DEG C and sieved, to obtain K 1.9 Cs 0.1 Al 0.995 Cr 0.005 SO4F3 deep red luminescent material.

[0077] Embodiment 6

[0078] The embodiment provides a Cr 3+ The doped novel fluorosulfate matrix deep red luminescent material is only doped with monovalent ions Rb + The luminescent spectrum is regulated. That is, a=0.05, b=0; the material is in a powder state, and the molecular formula is as follows: K 1.9 Rb 0.1 Al 0.995 Cr 0.005 SO4F3.

[0079] The preparation method is as follows:

[0080] S1: according to the stoichiometric ratio of each substance calculated according to the molecular formula, potassium sulfate, rubidium sulfate, aluminum fluoride and chromium fluoride with purity of AR and above are used as raw materials, and the mass is 1.2589 g, 0.1015 g, 0.6354 g and 0.0041 g respectively. After adding an appropriate amount of anhydrous ethanol into the agate mortar and grinding uniformly, a precursor is obtained;

[0081] S2: the precursor in S1 is ground in the agate mortar for 1 hour until it is uniformly ground, then it is loaded into an alumina crucible, and is heated to 500℃ at a rate of 5℃ / min in an air atmosphere, and is heat-treated and calcined for 2 hours, and then is cooled to room temperature with the furnace, to obtain a pre-calcined sample;

[0082] S3: the pre-calcined sample in S2 is placed in an agate mortar and ground for 0.5 hours until it is uniformly ground, and then is loaded into an alumina crucible again, and is heated to 650℃ at a rate of 5℃ / min in an air atmosphere, and is heat-treated and calcined for 10 hours, and then is cooled to room temperature with the furnace, and the obtained product is ground into a powder without particles;

[0083] S4: the product after grinding in S3 is added with an appropriate amount of deionized water and ultrasonically oscillated for 30 min, and then is placed in a centrifuge tube, and is centrifuged at a speed of 11000 r / min for 15 min, and then is dried at 100℃ and sieved, to obtain K 1.9 Rb 0.1 Al 0.995 Cr 0.005 SO4F3 deep red luminescent material.

[0084] Example 7

[0085] The present embodiment provides a Cr 3+ doped novel fluorosulfate matrix deep red luminescent material, which is only doped with monovalent ion Na + The luminescent spectrum is regulated. That is, a=0.05, b=0; the material is in powder form, and the molecular formula is as follows: K 1.9 Na 0.1 Al 0.995 Cr 0.005 SO4F3.

[0086] The preparation method is as follows:

[0087] S1: according to the stoichiometric ratio of each substance calculated according to the molecular formula, potassium sulfate, sodium sulfate, aluminum fluoride and chromium fluoride with purity of AR and above are used as raw materials, and the mass is 1.2896 g, 0.0553 g, 0.6509 g and 0.0042 g respectively. After adding an appropriate amount of anhydrous ethanol into the agate mortar and grinding uniformly, a precursor is obtained;

[0088] S2: The precursor in S1 was ground in a agate mortar for 1 hour until it was ground uniformly, then was loaded into an alumina crucible, and was heated to 500 DEG C at a rate of 5 DEG C / min under air atmosphere, and was heat-treated and calcined for 2 hours, and was cooled to room temperature with the furnace, to obtain a pre-calcined sample;

[0089] S3: The pre-calcined sample in S2 was placed in an agate mortar, and was ground for 0.5 hours until it was ground uniformly, then was again loaded into an alumina crucible, and was heated to 650 DEG C at a rate of 5 DEG C / min under air atmosphere, and was heat-treated and calcined for 10 hours, and was cooled to room temperature with the furnace, and the resulting product was ground to a powder without particles;

[0090] S4: The product after grinding in S3 was added to a proper amount of deionized water, and was ultrasonically vibrated for 30 min, then was placed in a centrifuge tube, and was centrifuged at a speed of 11000 r / min for 15 min, and was dried at 100 DEG C and sieved, to obtain K 1.9 Na 0.1 Al 0.995 Cr 0.005 SO4F3 deep red luminescent material.

[0091] Example 8

[0092] This example provides a Cr 3+ doped novel fluorosulfate matrix deep red luminescent material, which is only doped with monovalent ion Na + to control the luminescent spectrum. That is, a=0.5, b=0; the material is in powder form, and the molecular formula is as follows: KNaAl 0.995 Cr 0.005 SO4F3.

[0093] The preparation method is as follows:

[0094] S1: According to the stoichiometric ratio of each substance, potassium sulfate, sodium sulfate, aluminum fluoride, and chromium fluoride with a purity of AR or above were used as raw materials, and the mass was 0.7193 g, 0.5863 g, 0.6898 g, and 0.0045 g, respectively. The precursor was obtained by grinding the above-mentioned substances in a proper amount of anhydrous ethanol in an agate mortar until they were uniformly mixed;

[0095] S2: The precursor in S1 was ground in a agate mortar for 1 hour until it was ground uniformly, then was loaded into an alumina crucible, and was heated to 500 DEG C at a rate of 5 DEG C / min under air atmosphere, and was heat-treated and calcined for 2 hours, and was cooled to room temperature with the furnace, to obtain a pre-calcined sample;

[0096] S3: The sample after calcination in S2 was put into a marver mortar and ground for 0.5 hours until it was uniformly ground, then was again put into an alumina crucible and heated at a rate of 5°C / min to 700°C under an air atmosphere, and after being kept and sintered for 10 hours, was cooled to room temperature with the furnace, and the resulting product was ground to a powder without particles;

[0097] S4: The product after grinding in S3 was added to a proper amount of deionized water and ultrasonically oscillated for 30 minutes, then was put into a centrifuge tube and centrifuged at a speed of 12000 r / min for 20 minutes, and was dried at 100°C and sieved to obtain KNaAl 0.995 Cr 0.005 SO4F3 deep red luminescent material.

[0098] The above description of the embodiments is for the purpose of enabling one of ordinary skill in the art to understand and use the invention. Various modifications to these embodiments can be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other embodiments without departing from the scope of the invention. Thus, the present invention is not intended to be limited to the embodiments described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A type of Cr 3+ A doped fluorosulfate-based deep red luminescent material, characterized in that, It has the following general chemical formula: K 2(1-a) A 2a Al (1-b) B b SO4F3:xCr 3+ , 0≤a≤0.5, 0≤b≤0.2, Where 0.1at%≤x≤20at%, A is one of Na, Cs, and Rb, B is one of Ga or In trivalent ions, and the luminescent center is Cr. 3+ .

2. A Cr as described in claim 1 3+ A method for preparing a doped fluorosulfate-based deep red luminescent material, characterized in that, Includes the following steps: S1: Weigh the raw materials according to the stoichiometric ratio of each substance required for the target product, add anhydrous ethanol and grind them to make them evenly mixed to obtain the precursor. S2: The precursor is loaded into an alumina crucible and pre-sintered to remove moisture and obtain a pre-sintered sample. S3: Take out the pre-sintered sample from S2, grind it again to make the mixture more uniform, and then put it back into the alumina crucible for calcination to obtain the target compound. S4: The target compound prepared in S3 was ultrasonically vibrated in deionized water, centrifuged, dried, and sieved to obtain the desired Cr crystals. 3+ Deep red luminescent material with doped fluorosulfate matrix.

3. A Cr according to claim 2 3+ A method for preparing a doped fluorosulfate-based deep red luminescent material, characterized in that, In S1, the raw materials include: compounds containing Na, Cs or Rb, trivalent ionic compounds containing Ga or In, potassium-containing compounds, chromium-containing compounds, aluminum-containing compounds, sulfur-containing compounds, and fluorine-containing compounds.

4. A Cr according to claim 3 3+ A method for preparing a doped fluorosulfate-based deep red luminescent material, characterized in that, The Na, Cs, or Rb-containing compounds include at least one of the following: oxides, nitrates, carbonates, hydroxides, or sulfates containing Na, Cs, or Rb. The trivalent ionic compound containing Ga or In includes at least one of the following: oxides, nitrates, carbonates, hydroxides, or fluorides containing Ga or In trivalent ions; The chromium-containing compound includes at least one of chromium oxide, chromium nitrate, chromium carbonate, or chromium fluoride. The potassium-containing compound includes at least one of potassium carbonate, potassium nitrate, or potassium sulfate; The aluminum-containing compound includes at least one of aluminum oxide, aluminum nitrate, aluminum hydroxide, or aluminum fluoride; The sulfur-containing compound includes at least one of sulfuric acid and sulfates. The fluorinated compound includes at least one of hydrofluoric acid and fluorides.

5. The Cr according to claim 2 3+ A method for preparing a doped fluorosulfate-based deep red luminescent material, characterized in that, In S2, the pre-sintering temperature is 300-550℃, and the pre-sintering time is 1-10 hours.

6. The Cr according to claim 2 3+ A method for preparing a doped fluorosulfate-based deep red luminescent material, characterized in that, In S3, the calcination temperature is 600-800℃, and the calcination time is 5-20 hours.

7. The Cr according to claim 2 3+ A method for preparing a doped fluorosulfate-based deep red luminescent material, characterized in that, In S2 and S3, the heating rate for both pre-sintering and calcination is 4-6℃ / min.

8. The Cr according to claim 2 3+ A method for preparing a doped fluorosulfate-based deep red luminescent material, characterized in that, In S3, the grinding time is 0.5-1 hour.

9. The Cr according to claim 2 3+ A method for preparing a doped fluorosulfate-based deep red luminescent material, characterized in that, In S4, the drying temperature is 50-250℃.

10. A Cr as described in claim 1 3+ The application of doped fluorosulfate matrix deep red luminescent materials is characterized by, This material can be used as a fluorescent material in plant lighting and growth, display technology, biomedicine, security and anti-counterfeiting, or photoelectric detection and sensing.

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