Novel Cr < 3 + >-doped fluorosulfate matrix dark red luminescent material as well as preparation and application thereof

Abstract

The invention relates to a Cr < 3 + >-doped novel fluorosulfate matrix dark red luminescent material as well as preparation and application thereof. The general chemical formula of the luminescent material is K2 (1-a) A2aAl (1-b) BbSO4F3: xCr < 3 + >, a is greater than or equal to 0 and less than or equal to 1, b is greater than or equal to 0 and less than or equal to 0.5, A is a first main group element or at least one of monovalent Ag, Cu and Au, B comprises one of trivalent ions of Ga, In, TI and Sc, and the luminescent center is Cr < 3 + >. The preparation method of the luminescent material comprises the following steps: weighing the raw materials according to the stoichiometric ratio of each substance, grinding to uniformly mix the raw materials, pre-sintering, grinding again to uniformly mix the raw materials, calcining again, centrifuging, drying and sieving to obtain the required luminescent material. Compared with the prior art, the Cr < 3 + >-doped novel fluorosulfate matrix dark red luminescent material prepared by the invention is simple in synthesis process, and in addition, hydrofluoric acid harmful to human and environment or toxic ammonium fluoride easy to decompose by heating is not required to provide a fluorine source in the synthesis process.

Description

Technical Field

[0001] The present invention relates to the technical field of deep red fluorescent material preparation, in particular to a Cr 3+ New doped fluorosulfate-based deep-red luminescent materials and their preparation and applications. Background Art

[0002] With the development of science and technology and the expansion of applications, deep red fluorescent materials have shown important application value in many fields, such as plant lighting growth, LED lighting, display technology, biomedicine, etc. Especially in the field of plant lighting, deep red light has a significant promoting effect on plant growth and photosynthesis. So far, red-emitting fluorescent materials are mainly based on luminescent materials activated by rare earth or transition metal ions, such as Eu 2+ 、Eu 3+ 、Sm 3+ , Pr 3+ and Mn 4+ However, their disadvantages are also obvious, such as the high price of rare earth ion raw materials, the synthesis of fluoride fluorescent materials mostly uses hydrofluoric acid that is harmful to the human body and the environment or toxic and easily decomposed by heating ammonium fluoride, rare earth ions or transition metal Mn 4+ The deep red light emission of ions is not obvious, which limits their application in plant growth lighting. The deep red light wavelength range required for plant lighting growth is between 650-800nm, and the spectral purity of deep red light needs to be high to reduce unnecessary influence from other light sources. In contrast, the transition metal Cr that can emit deep red light 3+ Doped fluorescent materials are expected to be used in LEDs due to their non-toxicity, low cost and high purity of deep red light spectrum. 3+ Doped fluorescent materials have strong red light (600-650nm) or deep red light (650-800nm) emission. 3+ The application of doped fluorescent materials in plant lighting in the deep red light band has been reported in the literature. 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. But so far, most of them are oxides and fluorides. When oxides are used as matrix materials, the preparation process is simple and the energy consumption is low. When fluorides are used as matrix materials, they have the advantages of high efficiency and high concentration doping to achieve high brightness emission.

[0003] In 2008, it was reported that a new fluoroaluminum sulfate mineral K2[(AlF3)SO4] was discovered in an Italian volcano crater. It is a natural mineral (Can.Mineral., 2008.46(3):693-700.). Regarding the rational combination of [AlO2F4] and [SO4] groups, statistics and analysis showed that there are only four examples of fluoroaluminum sulfate compounds known so far, namely the natural mineral A2AlSO4F3 (A=K, NH4) and the artificially synthesized fluoroaluminum sulfate compounds Li4MA1(SO4)2F4 (M=Rb, Cs), Na2AlSO4F3 (Inorg.Chem., 2024.63(3):1674-1681). Among them, the artificial synthesis process of K2AlSO4F3 has not been reported so far. K2AlSO4F3 crystallizes in the orthorhombic Pbcn space group, where the unit cell parameters α=β=γ=90°. Transition metal ion Cr 3+ Ions, whose electronic configuration is 3d 3 ,Cr 3+ The emission of ions depends on the crystal field environment. Fluorosulfate combines the properties of fluoride and sulfate and exhibits good chemical stability.

[0004] Therefore, it is particularly important to develop more efficient and stable new deep-red fluorescent materials using fluorosulfates. Summary of the invention

[0005] The purpose of the present invention is to provide a Cr 3+ New doped fluorosulfate matrix deep red luminescent material and its preparation and application. 3+ The doped new fluorosulfate-based deep-red luminescent material has a simple synthesis process. In addition, during the synthesis process, no hydrofluoric acid, which is harmful to humans and the environment, or toxic ammonium fluoride, which is easily decomposed by heating, is required to provide a fluorine source.

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

[0007] The present invention provides a Cr 3+ The new doped fluorosulfate matrix deep red luminescent material has the following chemical 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 first main group 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 luminescence center is Cr 3+ .

[0009] The present invention also provides a Cr 3+ The preparation method of the novel doped fluorosulfate matrix deep red luminescent material comprises the following steps:

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

[0011] S2: loading the precursor into an alumina crucible, performing pre-sintering, removing moisture therein, and obtaining a pre-sintered sample;

[0012] S3: taking out the pre-sintered sample in S2, grinding it again to make the mixture more uniform, and then putting it into an alumina crucible again for calcination to obtain the target compound;

[0013] S4: The target compound prepared in S3 is ultrasonically shaken in deionized water, centrifuged, dried, and sieved to obtain the desired crystal particles of Cr 3+ New doped fluorosulfate-based deep-red luminescent materials.

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

[0015] Further, the compound containing the first main group element or monovalent Ag, Cu, Au comprises: at least one of oxides, nitrates, carbonates, hydroxides or sulfates containing the first main group element or monovalent Ag, Cu, Au;

[0016] The trivalent ion compound containing Ga, In, Ti, and Sc includes at least one of an oxide, a nitrate, a carbonate, a hydroxide, or a fluoride containing a trivalent ion of Ga, In, Ti, or 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 and sulfate;

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

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

[0023] Furthermore, in S3, the calcination temperature is 600-800° C., and the calcination time is 5-20 hours.

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

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

[0026] Furthermore, in S4, the drying temperature is 50-250°C.

[0027] The present invention also provides a Cr 3+ The application of a new type of doped fluorosulfate matrix deep red luminescent material, which is used as a fluorescent material in plant lighting growth, display technology, biomedicine, security and anti-counterfeiting, photoelectric detection and sensing.

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

[0029] 1. Cr prepared by the present invention 3+ The doped new fluorosulfate-based deep-red luminescent material has a simple synthesis process. In addition, during the synthesis process, no hydrofluoric acid, which is harmful to humans and the environment, or toxic ammonium fluoride, which is easily decomposed by heating, is required to provide a fluorine source.

[0030] 2. The present invention can be achieved by selecting Na + Ion partial replacement of K + ions, partially replacing the expensive K2SO4 with the cheap Na2SO4, which reduces the cost and increases the luminous intensity instead of decreasing, making it more suitable for industrial production.

[0031] 3. The present invention selects fluorosulfate without hydrofluoric acid as the luminescent matrix, which has a simple synthesis process, simple and safe operation, low equipment requirements, a wide source of raw materials, and is suitable for industrial production. The deep red material of the present invention has a narrow-band emission in the deep red region, and the luminescent band is located in the deep red band between 650-800nm, with a peak value of 694nm, which can be well matched with the absorption peak band of plant phytochrome PFR. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0033] Figure 2 is the diffuse reflectance spectrum of the deep red luminescent material prepared in Example 1;

[0034] Figure 3 This is the emission spectrum of the deep red luminescent material prepared in Example 1;

[0035] Figure 4 The emission spectra of the deep red luminescent material samples prepared in Example 1 and Example 8 are compared. DETAILED DESCRIPTION

[0036] The specific implementation methods of the present invention are described in detail below through examples. These examples are implemented on the premise of the scheme described in the present invention, and provide detailed implementation methods and specific operating processes, but the protection scope of the present invention is not limited to the following examples.

[0037] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. Any features such as component models, material names, connection structures, preparation methods, materials, structures or composition ratios not clearly described in this technical solution are deemed to be common technical features disclosed in the prior art.

[0038] The present invention successfully synthesized Cr 3+ A series of doped K2AlSO4F3 deep red fluorescent materials without hydrofluoric acid and their preparation and application. The present invention regulates the position of cations on the basis of the original structure. Monovalent ions of the first main group elements such as Na, Rb, Cs or Cu, Ag, Au occupy the (A) position, and trivalent ions such as Ga, In, TI, Sc occupy the (B) position. The present invention selects Na, Rb, Cs or Cu, Ag, Au ions to partially replace K ions, and Ga, In, TI, Sc ions to partially replace Al ions, thereby achieving additional ion doping at the (A) position and the (B) position, thereby regulating the luminescence spectrum of the synthesized material, using low-cost raw materials, and making it have better performance. When no additional ions are doped, the chemical formula of the present invention is: K2AlSO4F3:xCr 3+ , the general 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, where 0.1at%≤x≤20at%.

[0039] In the present invention, the Cr 3+ The doped fluorescent material is placed in a strong crystal field and spin-forbidden 2 E→4 The narrow emission band of A2 transition. The narrow-band emission in the deep red range has the advantages of promoting photosynthesis, promoting lateral growth and flowering of plants, spectral purity, reducing energy waste, and accurately controlling the light environment in plant lighting. These advantages have made narrow-band emission light sources widely used in modern agriculture and horticulture. Using fluorosulfate K2AlSO4F3 as the matrix, the synthesis process does not require hydrofluoric acid raw materials that are harmful to humans and the environment. A series of K 2(1-a) A 2a Al (1-b) B b SO4F3:xCr 3+ Deep red fluorescent material.

[0040] Example 1

[0041] This embodiment provides a Cr 3+ The novel fluorosulfate matrix deep red luminescent material doped with Cr 3+ In addition, no additional ions are doped at the (A) position and the (B) position. The material is in powder form and has the following molecular formula: K2Al 0.995 Cr 0.005 SO4F3:0.5at%Cr 3+ .

[0042] The preparation method is as follows:

[0043] S1: Calculate the stoichiometric ratio of each substance according to the molecular formula, and use potassium sulfate, aluminum fluoride, and chromium fluoride with AR purity or above as raw materials, with masses of 1.3490g, 0.6468g, and 0.0042g respectively. Add appropriate amount of anhydrous ethanol in an agate mortar and grind and mix evenly to obtain a precursor;

[0044] S2: The precursor in S1 was ground in an agate mortar for 1 hour until it was evenly ground, then placed in an alumina crucible, heated to 550°C at a rate of 5°C / min in an air atmosphere, kept warm and sintered for 2 hours, and then cooled to room temperature with the furnace to obtain a pre-sintered sample;

[0045] S3: The pre-sintered sample in S2 is placed in an agate mortar and ground for 0.5 hours until it is evenly ground. It is then placed in an alumina crucible again and heated to 700°C at a rate of 5°C / min in an air atmosphere. After being kept warm and sintered for 10 hours, it is cooled to room temperature in the furnace. The target product is taken out and ground into a powder without granularity.

[0046] S4: The target product ground in S3 was added with an appropriate amount of deionized water and ultrasonically vibrated for 30 minutes, then placed in a centrifuge tube, centrifuged at a speed of 12000 r / min for 20 minutes, dried at 100°C and sieved to obtain K2Al0.995 Cr 0.005 SO4F3:0.5at%Cr 3+ Deep red luminescent material.

[0047] The obtained product K2AlSO4F3:0.5at%Cr 3+ Phase analysis was performed using X-ray powder diffraction analysis, 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 pure phase; Figure 2 This is the UV-visible diffuse reflectance spectrum of the sample. It can be seen from the figure that the sample has an obvious absorption peak in the 200-600nm band, and there is absorption in the ultraviolet and green regions; Figure 3 The emission spectrum of the sample shows that the sample can emit deep red light of 694nm under the excitation of 553nm, especially close to the deep red light region of 700nm, which has a significant effect on the photosynthesis, morphological construction and physiological activities of plants. The emission spectrum belongs to narrow-band emission. Figure 4 This is an emission spectrum graph comparing the deep red luminescent material samples prepared in Example 1 and Example 8, wherein half of the K is replaced by Na. It can be seen that the cost of preparing the sample is reduced, and the luminescent intensity is still 1.6 times that of the case without replacement.

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

[0049] Example 2

[0050] This embodiment provides a Cr 3+ The novel fluorosulfate matrix deep red luminescent material doped with Cr 3+ In addition, no additional ions are doped at the (A) position or the (B) position. The material is in powder form and has the following molecular formula: K2Al 0.99 Cr 0.01 SO4F3:1.0at%Cr 3+ .

[0051] The preparation method is as follows:

[0052] S1: Calculate the stoichiometric ratio of each substance according to the molecular formula, and use potassium sulfate, aluminum fluoride, and chromium fluoride with AR purity or above as raw materials, with masses of 1.3483g, 0.6433g, and 0.0084g respectively. Add an appropriate amount of anhydrous ethanol in an agate mortar and grind and mix evenly to obtain a precursor;

[0053] S2: The precursor in S1 was ground in an agate mortar for 1 hour until it was evenly ground, then placed in an alumina crucible, heated to 500°C at a rate of 5°C / min in an air atmosphere, kept warm and sintered for 2 hours, and then cooled to room temperature with the furnace to obtain a pre-sintered sample;

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

[0055] S4: The ground product in S3 was added to an appropriate amount of deionized water and ultrasonically vibrated for 30 minutes, then placed in a centrifuge tube, centrifuged at a speed of 11000 r / min for 15 minutes, dried at 100°C and sieved to obtain K2Al 0.99 Cr 0.01 SO4F3:1.0at%Cr 3+ Deep red luminescent material.

[0056] Example 3

[0057] This embodiment provides a Cr 3+ A new type of fluorosulfate-based deep-red luminescent material doped with trivalent ions Ga 3+ The luminescence spectrum is regulated. That is, a=0, b=0.2; the material is in powder form, and the molecular formula is as follows: K2Al 0.795 Ga 0.2 Cr 0.005 SO4F3:0.5at%Cr 3+ .

[0058] The preparation method is as follows:

[0059] S1: Calculate the stoichiometric ratio of each substance according to the molecular formula, and use potassium sulfate, aluminum fluoride, gallium fluoride, and chromium fluoride of AR purity or above as raw materials, with masses of 1.3058g, 0.5003g, 0.1899g, and 0.0041g respectively. Add an appropriate amount of anhydrous ethanol in an agate mortar and grind and mix evenly to obtain a precursor;

[0060] S2: The precursor in S1 was ground in an agate mortar for 1 hour until it was evenly ground, then placed in an alumina crucible, heated to 500°C at a rate of 5°C / min in an air atmosphere, kept warm and sintered for 2 hours, and then cooled to room temperature with the furnace to obtain a pre-sintered sample;

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

[0062] S4: The ground product in S3 was added to an appropriate amount of deionized water and ultrasonically vibrated for 30 minutes, then placed in a centrifuge tube, centrifuged at a speed of 11000 r / min for 15 minutes, dried at 100°C and sieved to obtain K2Al 0.795 Ga 0.2 Cr 0.005 SO4F3:0.5at%Cr 3+ Deep red luminescent material.

[0063] Example 4

[0064] This embodiment provides a Cr 3+ A new type of fluorosulfate-based deep-red luminescent material doped with only trivalent ions In 3+ The luminescence spectrum is regulated. That is, a=0, 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 SO4F3:0.5at%Cr 3+ .

[0065] The preparation method is as follows:

[0066] S1: Calculate the stoichiometric ratio of each substance according to the molecular formula, and use potassium sulfate, aluminum fluoride, indium fluoride, and chromium fluoride of AR purity or above as raw materials, with masses of 1.3264g, 0.6041g, 0.0654g, and 0.0041g respectively. Add an appropriate amount of anhydrous ethanol in an agate mortar and grind and mix evenly to obtain a precursor;

[0067] S2: The precursor in S1 was ground in an agate mortar for 1 hour until it was evenly ground, then placed in an alumina crucible, heated to 500°C at a rate of 5°C / min in an air atmosphere, kept warm and calcined for 2 hours, and then cooled to room temperature with the furnace to obtain a pre-sintered sample;

[0068] S3: The pre-sintered sample in S2 was placed in an agate mortar and ground for 0.5 hours until it was evenly ground, then placed in an alumina crucible again, heated to 650°C at a rate of 5°C / min in an air atmosphere, kept warm and calcined for 10 hours, then cooled to room temperature with the furnace, and the obtained product was ground into a powder without granularity;

[0069] S4: The ground product in S3 was added to an appropriate amount of deionized water and ultrasonically vibrated for 30 minutes, then placed in a centrifuge tube, centrifuged at a speed of 11000 r / min for 15 minutes, dried at 100°C and sieved to obtain K2Al 0.945 In 0.05 Cr 0.005 SO4F3:0.5at%Cr 3+ Deep red luminescent material.

[0070] Example 5

[0071] This embodiment provides a Cr 3+ A new type of fluorosulfate-based deep red luminescent material doped with only monovalent ions Cs + The luminescence 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 Cs 0.1 Al 0.995 Cr 0.005 SO4F3:0.5at%Cr 3+ .

[0072] The preparation method is as follows:

[0073] S1: Calculate the stoichiometric ratio of each substance according to the molecular formula, and use potassium sulfate, cesium sulfate, aluminum fluoride, and chromium fluoride of AR purity or above as raw materials, with masses of 1.2366g, 0.1352g, 0.6242g, and 0.0041g respectively. Add an appropriate amount of anhydrous ethanol in an agate mortar and grind and mix evenly to obtain a precursor;

[0074] S2: The precursor in S1 was ground in an agate mortar for 1 hour until it was evenly ground, then placed in an alumina crucible, heated to 500°C at a rate of 5°C / min in an air atmosphere, kept warm and sintered for 2 hours, and then cooled to room temperature with the furnace to obtain a pre-sintered sample;

[0075] S3: The pre-sintered sample was placed in an agate mortar and ground for 0.5 hours until it was evenly ground, then placed in an alumina crucible again, heated to 650°C at a rate of 5°C / min in an air atmosphere, kept warm and calcined for 10 hours, then cooled to room temperature with the furnace, and the obtained product was ground into a powder without granularity;

[0076] S4: The ground product in S3 was added to an appropriate amount of deionized water and ultrasonically vibrated for 30 minutes, then placed in a centrifuge tube, centrifuged at a speed of 11000 r / min for 15 minutes, dried at 100°C and sieved to obtain K 1.9 Cs 0.1 Al 0.995 Cr 0.005 SO4F3:0.5at%Cr3+ Deep red luminescent material.

[0077] Example 6

[0078] This embodiment provides a Cr 3+ A new type of fluorosulfate-based deep red luminescent material doped with only monovalent ions Rb + The luminescence 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 R 0.1 Al 0.995 Cr 0.005 SO4F3:0.5at%Cr 3+ .

[0079] The preparation method is as follows:

[0080] S1: Calculate the stoichiometric ratio of each substance according to the molecular formula, and use potassium sulfate, rubidium sulfate, aluminum fluoride, and chromium fluoride of AR purity or above as raw materials, with masses of 1.2589g, 0.1015g, 0.6354g, and 0.0041g respectively. Add an appropriate amount of anhydrous ethanol in an agate mortar and grind and mix evenly to obtain a precursor;

[0081] S2: The precursor in S1 was ground in an agate mortar for 1 hour until it was evenly ground, then placed in an alumina crucible, heated to 500°C at a rate of 5°C / min in an air atmosphere, kept warm and calcined for 2 hours, and then cooled to room temperature with the furnace to obtain a pre-calcined sample;

[0082] S3: The pre-calcined sample in S2 was placed in an agate mortar and ground for 0.5 hours until it was evenly ground, then placed in an alumina crucible again, heated to 650°C at a rate of 5°C / min in an air atmosphere, kept warm and calcined for 10 hours, then cooled to room temperature with the furnace, and the obtained product was ground into a powder without granularity;

[0083] S4: The ground product in S3 was added to an appropriate amount of deionized water and ultrasonically vibrated for 30 minutes, then placed in a centrifuge tube, centrifuged at a speed of 11000 r / min for 15 minutes, dried at 100°C and sieved to obtain K 1.9 R 0.1 Al 0.995 Cr 0.005 SO4F3:0.5at%Cr 3+ Deep red luminescent material.

[0084] Example 7

[0085] This embodiment provides a Cr 3+ A new type of fluorosulfate-based deep red luminescent material doped with only monovalent ions Na +The luminescence 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 SO4F3:0.5at%Cr 3+ .

[0086] The preparation method is as follows:

[0087] S1: Calculate the stoichiometric ratio of each substance according to the molecular formula, and use potassium sulfate, sodium sulfate, aluminum fluoride, and chromium fluoride with AR purity or above as raw materials, with masses of 1.2896g, 0.0553g, 0.6509g, and 0.0042g respectively. Add an appropriate amount of anhydrous ethanol in an agate mortar and grind and mix evenly to obtain a precursor;

[0088] S2: The precursor in S1 was ground in an agate mortar for 1 hour until it was evenly ground, then placed in an alumina crucible, heated to 500°C at a rate of 5°C / min in an air atmosphere, kept warm and calcined for 2 hours, and then 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 ground for 0.5 hours until it was evenly ground, then placed in an alumina crucible again, heated to 650°C at a rate of 5°C / min in an air atmosphere, kept warm and calcined for 10 hours, then cooled to room temperature with the furnace, and the obtained product was ground into a powder without granularity;

[0090] S4: The ground product in S3 was added to an appropriate amount of deionized water and ultrasonically vibrated for 30 minutes, then placed in a centrifuge tube, centrifuged at a speed of 11000 r / min for 15 minutes, dried at 100°C and sieved to obtain K 1.9 Na 0.1 Al 0.995 Cr 0.005 SO4F3:0.5at%Cr 3+ Deep red luminescent material.

[0091] Example 8

[0092] This embodiment provides a Cr 3+ A new type of fluorosulfate-based deep red luminescent material doped with only monovalent ions Na + The luminescence spectrum is regulated. 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 SO4F3:0.5at%Cr 3+ .

[0093] The preparation method is as follows:

[0094] S1: Calculate the stoichiometric ratio of each substance according to the molecular formula, and use potassium sulfate, sodium sulfate, aluminum fluoride, and chromium fluoride with AR purity or above as raw materials, with masses of 0.7193g, 0.5863g, 0.6898g, and 0.0045g respectively. Add appropriate amount of anhydrous ethanol in an agate mortar and grind and mix evenly to obtain a precursor;

[0095] S2: The precursor in S1 was ground in an agate mortar for 1 hour until it was evenly ground, then placed in an alumina crucible, heated to 550°C at a rate of 5°C / min in an air atmosphere, kept warm and sintered for 2 hours, and then cooled to room temperature with the furnace to obtain a calcined sample;

[0096] S3: The calcined sample in S2 was placed in an agate mortar and ground for 0.5 hours until it was evenly ground, then placed in an alumina crucible again, heated to 700°C at a rate of 5°C / min in an air atmosphere, kept warm and sintered for 10 hours, then cooled to room temperature with the furnace, and the obtained product was ground into a powder without granularity;

[0097] S4: The ground product in S3 was added with an appropriate amount of deionized water and ultrasonically vibrated for 30 minutes, then placed in a centrifuge tube, centrifuged at a speed of 12000 r / min for 20 minutes, dried at 100°C and sieved to obtain KNaAl 0.995 Cr 0.005 SO4F3:0.5at%Cr 3+ Deep red luminescent material.

[0098] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A Cr 3+ A novel doped fluorosulfate matrix deep red luminescent material, characterized in that: Has the following chemical formula: 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%, A is a first main group 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 luminescence center is Cr 3+ .

2. A Cr as claimed in claim 1 3+ A method for preparing a novel doped fluorosulfate matrix deep red luminescent material, characterized in that: The following steps are involved: S1: weigh the raw materials according to the stoichiometric ratio of each substance of the raw materials required for the target product, add anhydrous ethanol and grind them to make them uniformly mixed to obtain a precursor; S2: loading the precursor into an alumina crucible, performing pre-sintering, removing moisture therein, and obtaining a pre-sintered sample; S3: taking out the pre-sintered sample in S2, grinding it again to make the mixture more uniform, and then putting it into the alumina crucible again for calcination to obtain the target compound; S4: The target compound prepared in S3 is ultrasonically shaken in deionized water, centrifuged, dried, and sieved to obtain the desired crystal particles of Cr 3+ New doped fluorosulfate-based deep-red luminescent materials.

3. A Cr according to claim 2 3+ A method for preparing a novel doped fluorosulfate matrix deep red luminescent material, characterized in that: In S1, the raw materials include: one or more of compounds containing first main group elements or monovalent Ag, Cu, Au, trivalent ion compounds containing Ga, In, Ti, Sc, 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 novel doped fluorosulfate matrix deep red luminescent material, characterized in that: The compound containing the first main group element or monovalent Ag, Cu, Au comprises: at least one of oxides, nitrates, carbonates, hydroxides or sulfates containing the first main group element or monovalent Ag, Cu, Au; The trivalent ion compound containing Ga, In, Ti, and Sc includes at least one of an oxide, a nitrate, a carbonate, a hydroxide, or a fluoride containing a trivalent ion of Ga, In, Ti, or Sc; 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 sulfate; The fluorine-containing compound includes at least one of hydrofluoric acid and fluoride.

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

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

7. The Cr according to claim 2 3+ A method for preparing a novel doped fluorosulfate matrix deep red luminescent material, characterized in that: In S2 and S3, the heating rates of pre-sintering and calcination were both 4-6°C / min.

8. The Cr according to claim 2 3+ A method for preparing a novel doped fluorosulfate matrix 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 novel doped fluorosulfate matrix deep red luminescent material, characterized in that: In S4, the drying temperature is 50-250°C.

10. A Cr as claimed in claim 1 3+ Application of a novel doped fluorosulfate matrix deep red luminescent material, characterized in that: This material is used as a fluorescent material in plant lighting growth, display technology, biomedicine, security and anti-counterfeiting, photoelectric detection and sensing.

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