A Mn 4+ Activation of a red-fluorescing fluoride (oxy)fluoride phosphor and method of preparation

Abstract

The application discloses a kind of Mn 4+ Activated fluorine (oxygen) oxide red fluorescent material and its preparation method;The application uses organic-inorganic hybrid fluoride manganese salt material as Mn 4+ Source preparation Mn 4+ Activated fluorine (oxygen) oxide red fluorescent material.The application uses organic-inorganic hybrid fluoride manganese salt material instead of all-inorganic fluoride manganese salt, manganese salt and permanganate as Mn 4+ Source, for preparing Mn 4+ Activated fluorine (oxygen) oxide red fluorescent material, significantly improve the luminescent efficiency of Mn 4+ Activated fluorine (oxygen) oxide red fluorescent material.

Description

Technical Field

[0001] This invention relates to the field of light-emitting functional materials for LEDs, specifically to a Mn 4+ Activated red fluorescent materials of fluoride (oxygen) compounds and their preparation methods. Background Technology

[0002] Compared to traditional lighting sources like incandescent and fluorescent lamps, white light-emitting diodes (LEDs) offer significant advantages such as low heat generation, low power consumption, fast response, flicker-free operation, and long lifespan, earning them the reputation as a next-generation solid-state lighting source. Currently, mainstream commercial white LEDs consist of a blue LED chip and a yellow phosphor (Y3Al5O3). 12 :Ce 3+ (YAG:Ce 3+ This type of white LED is packaged and assembled; however, it lacks red light components in its emission spectrum, resulting in a high color temperature (CCT>4500K) and a low color rendering index (CRI, Ra<80), making it difficult to meet the application requirements of indoor and outdoor lighting and wide color gamut liquid crystal display (LCD) backlights. To improve the light quality of this type of white LED, it is necessary to add an appropriate amount of red phosphor material to the device to supplement the red light emission component. The red light emission component plays a role in reducing the white light color temperature and improving the white light color rendering index.

[0003] Mn 4+ Activated fluoride (oxygen) red phosphors can be effectively excited by 300–400 nm ultraviolet or near-ultraviolet light and 400–500 nm blue light, emitting a narrow band of red light in the 600–650 nm range, which is within the sensitive region of the human eye. Furthermore, its strongest absorption peak matches the emission peak (450–470 nm) of commercially available blue LED chips, making it an ideal red phosphor material for white LEDs. Currently, Mn... 4+ Numerous reports have been published on activated fluoride (oxygen) red fluorescent materials, primarily including A2M. 1-x F6:xMn 4+ A3N 1-x F6:xMn 4+ BM 1-x F6:xMn 4+ A2Z 1-x O2F4:xMn 4+ and A2Q 1-x OF5:xMn 4+ These compound systems hold promise for application in white LED devices (fluoride phosphor materials and their semiconductor light-emitting devices, CN 102827601A; preparation method of fluoride phosphor materials, CN 103980896A). However, Mn... 4+Mn is a parity-forbidden luminescent ion, and achieving high luminous efficiency requires a high doping concentration in the crystal lattice. Currently, Mn... 4+ Mn doped with fluorine (oxide) red fluorescent materials 4+ The doping concentration remains low, generally below 10 mol%, resulting in low absorption efficiency of the phosphor for excitation light (blue light), thus leading to a low external quantum efficiency of phosphor emission. More importantly, current Mn... 4+ The manganese source used in the preparation of activated fluoride (oxygen) red fluorescent materials is an inorganic fluoromanganate, manganate, and permanganate containing alkali metal or alkaline earth metal ions. Alkali metal (Li, Na, K, Rb, Cs) or alkaline earth metal (Ca, Sr, Ba) ions, which are not part of the matrix composition, can easily enter the crystal lattice of the target fluoride (oxygen) red fluorescent material during synthesis, becoming lattice defects—fluorescence quenching sites that lead to decreased luminescence and thus lower luminescence performance. Therefore, increasing Mn... 4+ The improvement of doping levels and reduction of lattice defects during the preparation of fluoride (oxide) red fluorescent materials, thereby enhancing their luminescence performance, promoting their application in the LED industry, and reducing dependence on rare earth materials, is of great practical significance. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a Mn 4+ This paper discloses a method for improving the luminescence performance of Mn(Ⅳ) activated fluoride (oxide) red phosphor materials and their preparation, specifically focusing on an improved method for Mn(Ⅳ) activated fluoride (oxide) red phosphor materials used in blue LED lighting and backlight displays. This method is simple, easy to implement, and universally applicable, and can significantly improve the luminescence performance of Mn(Ⅳ) activated fluoride (oxide) red phosphor materials. 4+ Activate the luminescence properties of fluoride (oxygen) red fluorescent materials, thereby reducing costs.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] A type of Mn 4+ A method for preparing activated fluoride (oxygen) red fluorescent materials, using organic-inorganic hybrid fluoromanganate materials as Mn 4+ Source preparation of Mn 4+ Activation of red fluorescent materials composed of fluoride (oxide) compounds. Specifically, this involves the preparation of Mn... 4+ In the process of activating red fluorescent fluoride materials, organic-inorganic hybrid fluoromanganate materials are used to replace all-inorganic fluoromanganate, manganate, and permanganate as Mn. 4+ The only source.

[0007] Preferably, the Mn 4+ The chemical composition of the activated fluoride (oxygen) red fluorescent material is: A2M1-x F6:xMn 4+ A3N 1-x F6:xMn 4+ BM 1-x F6:xMn 4+ A2Z 1-x O2F4:xMn 4+ A2Q 1-x OF5:xMn 4+ Where A is Li + Na + K + 、Rb + Cs + (NH4) + [(CH3)4N] + One or more combinations of B, where B is Mg 2+ Ca 2+ 、Sr 2+ Ba 2+ Zn 2+ One or more combinations of Si, where M is Si 4+ 、Ge 4+ Sn 4+ Ti 4+ Zr 4+ Hf 4+ Mn 4+ One or more combinations of A and B, where N is Al 3 + Ga 3+ In 3+ Bi 3+ V 3+ and Sc 3+ and Y 3+ Z is a combination of one or more rare earth trivalent ions, where W is the rare earth element. 6+ and Mo 6+ One or a combination of two of them, where Q is Nb 5+ Ta 5+ and V 5+ One or more combinations of Mn, where x is Mn 4+ The molar percentage coefficient relative to the M, N, Z, or Q ions, 0 <x≤1.0。

[0008] More preferably, the Mn 4+ Methods for preparing activated red fluorescent materials of fluoride (oxygen) compounds include liquid-phase coprecipitation and cation exchange methods.

[0009] (1) Prepared by liquid-phase coprecipitation method, including the following steps:

[0010] Compounds containing M, N, Z, or Q ions are added to an HF solution, followed by the addition of an organic-inorganic hybrid fluoromanganate material, and the mixture is stirred for 5-30 minutes. Finally, compounds containing A or B ions are added, and the mixture is stirred for another 5-360 minutes. The resulting precipitate is collected, washed, and dried to obtain the Mn. 4+ Activate fluoride (oxygen) red fluorescent materials;

[0011] (2) Prepared by cation exchange method, including the following steps:

[0012] A compound containing M, N, Z, or Q ions is added to an HF solution, followed by a compound containing A or B ions. The mixture is stirred for 30-360 minutes. The resulting precipitate is collected, washed, and dried to obtain the fluoride (oxygen) matrix precursor. Finally, an organic-inorganic hybrid fluoromanganate material is dissolved in an HF aqueous solution, and then the fluoride (oxygen) matrix precursor is added. The mixture is stirred continuously for 5-360 minutes. The resulting precipitate is collected, washed, and dried to obtain the Mn. 4+ Activate red fluorescent materials containing fluorine (oxygen) compounds.

[0013] More preferably, in the liquid-phase coprecipitation method and the cation exchange method, the compound containing M, N, Z or Q ions is one or more of the elements, oxides, acids and bases containing M, N, Z or Q ions; the compound containing A or B ions is one or more of the bases and salts containing A or B ions.

[0014] More preferably, the compound containing M, N, Z or Q ions in the liquid-phase coprecipitation method and the cation exchange method is one or a combination of two or more of the following: silicon powder, tin powder, silicon dioxide, germanium oxide, hafnium oxide, titanium oxide, tin oxide, zirconium oxide, aluminum oxide, gallium oxide, indium oxide, bismuth oxide, vanadium pentoxide, vanadium trioxide, scandium oxide, yttrium oxide, tungsten oxide, molybdenum oxide, niobium oxide, tantalum oxide, fluorosilicic acid, fluorogermanic acid, fluorotitanic acid, fluorozirconic acid, fluorohafnium acid, tungstic acid, molybdenum acid, fluoroniobic acid, fluorotantalic acid, aluminum hydroxide, and potassium fluoromanganate. The compounds containing A or B ions are lithium hydroxide, potassium hydroxide, sodium hydroxide, rubidium hydroxide, cesium hydroxide, ammonia, tetramethylammonium hydroxide, tetramethylammonium fluoride, tetramethylammonium fluoride tetrahydrate, tetramethylammonium acetate, tetramethylammonium sulfate, lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride, cesium fluoride, ammonium fluoride, lithium hydrofluoride, sodium hydrofluoride, potassium hydrofluoride, ammonium hydrofluoride, lithium carbonate, sodium carbonate, potassium carbonate, rubidium carbonate, cesium carbonate, ammonium carbonate, lithium bicarbonate, sodium bicarbonate, potassium bicarbonate, rubidium bicarbonate, and cesium bicarbonate. Ammonium bicarbonate, lithium bisulfate, sodium bisulfate, potassium bisulfate, rubidium bisulfate, cesium bisulfate, ammonium bisulfate, lithium sulfate, sodium sulfate, potassium sulfate, rubidium sulfate, cesium sulfate, ammonium sulfate, lithium nitrate, sodium nitrate, potassium nitrate, rubidium nitrate, cesium nitrate, ammonium nitrate, lithium phosphate, sodium phosphate, potassium phosphate, rubidium phosphate, cesium phosphate, ammonium phosphate, lithium hydrogen phosphate, sodium hydrogen phosphate, potassium hydrogen phosphate, rubidium hydrogen phosphate, cesium hydrogen phosphate, ammonium hydrogen phosphate, lithium chloride, sodium chloride, potassium chloride, rubidium chloride, cesium chloride, ammonium chloride.

[0015] More preferably, the mass concentration of the HF solution in the liquid-phase coprecipitation method and the cation exchange method is 30-49%.

[0016] Preferably, the chemical composition of the organic-inorganic hybrid fluoromanganate material is: T2MnF6·xH2O; where T is an organic group [C(NH2)3]. + [(CH3)4N] + [(CH3CH2)4N] + [(CH3CH2CH2)4N] + [(CH3CH2CH2CH2)4N] + One or more combinations of the following; x is the water of crystallization contained in the crystal lattice, 0≤x≤5.

[0017] Preferably, the organic-inorganic hybrid fluoromanganate material is an organic-inorganic hybrid fluoromanganate polycrystalline powder material or an organic-inorganic hybrid fluoromanganate single crystal material.

[0018] More preferably, the preparation method of the organic-inorganic hybrid fluoromanganate polycrystalline powder material includes liquid phase method 1 and liquid phase method 2;

[0019] (A) Prepared using liquid phase method 1, including the following steps:

[0020] The compound containing the organic group T, permanganate, or manganate is added to an HF solution and stirred until dissolved. Then, an aqueous H2O2 solution is added dropwise until the solution changes color and an orange-yellow precipitate is formed. After aging, filtration, washing, and drying, the organic-inorganic hybrid fluoromanganate polycrystalline powder material is obtained.

[0021] (B) Prepared using liquid phase method 2, including the following steps:

[0022] Mn-containing 4+ The fluoride is added to the HF solution and stirred to dissolve it. Then, a compound containing the organic group T is added and stirring is continued for 5-360 minutes. The resulting precipitate is washed and dried to obtain the organic-inorganic hybrid fluoromanganate polycrystalline powder material.

[0023] More preferably, the compound containing the organic group T in liquid phase method 1 is a compound containing [C(NH2)3]. + [(CH3)4N] + [(CH3CH2)4N] + [(CH3CH2CH2)4N] + [(CH3CH2CH2CH2)4N] + One or more combinations of halides, acids, bases and salts;

[0024] More preferably, the permanganate or manganate in liquid phase method 1 is one or a combination of two or more of LiMnO4, NaMnO4, KMnO4, Ca(MnO4)2, Li2MnO4, Na2MnO4, K2MnO4, and Mg(MnO4)2; the addition of H2O2 aqueous solution is carried out at 0-5°C.

[0025] More preferably, in liquid phase method 1, the mass concentration of the HF solution is 30-49%; and the mass concentration of the H2O2 aqueous solution is 15-30%.

[0026] More preferably, the compound containing the organic group T is one or a combination of two or more of guanidine carbonate, guanidine hydrochloride, tetramethylammonium fluoride, tetramethylammonium fluoride tetrahydrate, tetramethylammonium acetate, tetramethylammonium sulfate, tetramethylammonium hydroxide, tetraethylammonium fluoride, tetrapropylammonium fluoride, and tetrabutylammonium fluoride.

[0027] More preferably, the compound containing the organic group T in liquid phase method 2 is a compound containing [C(NH2)3]. + [(CH3)4N] + [(CH3CH2)4N] +[(CH3CH2CH2)4N] + [(CH3CH2CH2CH2)4N] + One or more combinations of halides, acids, bases and salts;

[0028] More preferably, the Mn-containing method 2 described in liquid phase method 2 4+ The fluoride is one or a combination of two or more of the following: Li2MnF6, Na2MnF6, K2MnF6, Rb2MnF6, Cs2MnF6, (NH4)2MnF6, and BaMnF6.

[0029] More preferably, the mass concentration of the HF solution in liquid phase method 2 is 30-49%.

[0030] More preferably, the compound containing the organic group T is one or a combination of two or more of guanidine carbonate, guanidine hydrochloride, tetramethylammonium fluoride, tetramethylammonium fluoride tetrahydrate, tetramethylammonium acetate, tetramethylammonium sulfate, tetramethylammonium hydroxide, tetraethylammonium fluoride, tetrapropylammonium fluoride, and tetrabutylammonium fluoride.

[0031] More preferably, the preparation method of the organic-inorganic hybrid fluoromanganate single crystal material includes the following steps: dissolving the organic-inorganic hybrid fluoromanganate polycrystalline powder material in HF solution, adding tetramethylammonium fluoride, heating it to make it a hot saturated solution, and then cooling it to room temperature to obtain the organic-inorganic hybrid fluoromanganate single crystal material.

[0032] More preferably, the HF solution has a mass concentration of 30-49%.

[0033] The Mn prepared by the above method 4+ Activate red fluorescent materials containing fluorine (oxygen) compounds.

[0034] Preferably, the Mn 4+ When activated, red fluorescent fluoride materials emit narrow-band red light with a main peak at 610–650 nm under ultraviolet or near-ultraviolet light at 300–400 nm and blue light at 400–510 nm.

[0035] Compared with the prior art, the advantages and positive effects of this invention are:

[0036] (1) The method of the present invention can effectively improve Mn 4+ Activating the luminescence properties of fluoride (oxygen) red phosphor materials significantly improves their excitation light absorption rate and luminescence efficiency. The improved luminescence properties of fluoride (oxygen) red phosphor materials can effectively improve the color quality of white LEDs when used in white LEDs, thereby enhancing the performance and user experience of products based on white LED devices.

[0037] (2) The organic-inorganic hybrid fluoromanganate material used in this invention has high solubility and is easy to dissolve, and can replace the current all-inorganic fluoromanganate as the sole manganese source precursor for the synthesis of higher Mn content. 4+ Fluoride (oxygen) compound red phosphor materials with higher doping concentrations for more efficient luminescence;

[0038] (3) The method of the present invention includes two liquid-phase synthesis routes. The preparation process is simple, easy to implement, mild and low cost, and can be industrialized on a large scale. Attached Figure Description

[0039] Figure 1 The XRD powder diffraction pattern of the organic-inorganic hybrid guanidine fluoromanganate [C(NH2)3]2MnF6 material prepared in Example 1 and the standard card pattern in the PDF card library are shown.

[0040] Figure 2 This refers to K2SiF6:Mn prepared in Example 5 using an organic-inorganic hybrid fluoromanganate as the manganese source. 4+ XRD powder diffraction pattern of red fluorescent material and standard card pattern of K2SiF6;

[0041] Figure 3 This refers to K2SiF6:Mn prepared in Example 5 using an organic-inorganic hybrid fluoromanganate as the manganese source. 4+ Room temperature excitation and emission spectra of red fluorescent material samples;

[0042] Figure 4 K2SiF6:Mn prepared in Example 5 and Comparative Examples 1, 3, 4, 5, and 6 4+ Comparison of room temperature emission spectral brightness of red fluorescent materials.

[0043] Figure 5 [(CH3)4N]2GeF6:Mn prepared for Example 20 and Comparative Example 20 4+ Comparison of room temperature emission spectral brightness of red fluorescent materials.

[0044] Figure 6 Cs2NbOF5:Mn prepared for Example 23 and Comparative Example 23 4+ Comparison of room temperature emission spectral brightness of red fluorescent materials. Detailed Implementation

[0045] The technical solutions of the present invention will be further described below with reference to specific embodiments and accompanying drawings. However, the following embodiments are only for enhancing the illustration of the technical solutions of the present invention and should not be construed as any limitation on the scope of the claimed invention. Furthermore, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, any modifications, equivalent substitutions, improvements, etc., made by those skilled in the art without creative effort to obtain all other embodiments should be included within the protection scope of the present invention.

[0046] In a specific embodiment of the present invention, Mn 4+ The activated fluoride (oxygen) red fluorescent material was prepared by the following steps:

[0047] (1) Preparation of organic-inorganic hybrid fluoromanganate materials, including two different liquid-phase synthesis methods, specifically including the following steps:

[0048] The first liquid-phase synthesis method:

[0049] The compound containing the organic group T, permanganate, or manganate is added to an HF solution and stirred until dissolved. Then, an aqueous H2O2 solution is added dropwise until the solution changes color and an orange-yellow precipitate is formed. After aging, filtration, washing, and drying, the organic-inorganic hybrid fluoromanganate polycrystalline powder material is obtained.

[0050] Furthermore, the obtained organic-inorganic hybrid fluoromanganate material can be dissolved again in HF solution, and an appropriate amount of compound containing organic group T can be added. The solution is heated by water bath or oil bath to prepare a hot saturated solution, and then cooled to room temperature to obtain organic-inorganic hybrid fluoromanganate single crystal.

[0051] The second liquid-phase synthesis method:

[0052] Mn-containing 4+ The fluoride is added to the HF solution and stirred to dissolve it. Then, a compound containing the organic group T is added and stirring is continued for 5-360 minutes. The resulting precipitate is washed and dried to obtain the organic-inorganic hybrid fluoromanganate polycrystalline powder material.

[0053] Furthermore, the obtained organic-inorganic hybrid fluoromanganate material can be dissolved again in HF solution, and an appropriate amount of compound containing organic group T can be added. The solution is heated by water bath or oil bath to prepare a hot saturated solution, and then cooled to room temperature to obtain organic-inorganic hybrid fluoromanganate single crystal.

[0054] (2)Mn 4+ Preparation of activated fluoride (oxygen) red fluorescent materials, including co-precipitation and cation exchange methods:

[0055] The first coprecipitation method:

[0056] Compounds containing M, N, Z, or Q ions are added to an HF solution, followed by the addition of a pre-prepared organic-inorganic hybrid fluoromanganate material, and the mixture is stirred for 5-30 minutes. Finally, compounds containing A or B ions are added, and the mixture is stirred for another 5-360 minutes. The resulting precipitate is collected, washed, and dried to obtain the Mn. 4+ Activate red fluorescent materials containing fluorine (oxygen) compounds.

[0057] The second cation exchange method:

[0058] A compound containing M, N, Z, or Q ions is added to an HF solution, followed by a compound containing A or B ions. The mixture is stirred for 30-360 minutes. The resulting precipitate is collected, washed, and dried to obtain the fluoride (oxygen) matrix precursor. Finally, a pre-prepared organic-inorganic hybrid fluoromanganate material is dissolved in an HF aqueous solution, and then the prepared fluoride (oxygen) matrix precursor is added. The mixture is stirred continuously for 5-360 minutes. The resulting precipitate is collected, washed, and dried to obtain the Mn. 4+ Activate red fluorescent materials containing fluorine (oxygen) compounds.

[0059] Examples 1 and 2 are for the preparation of manganese-based organic-inorganic hybrid guanidine fluoromanganate [C(NH2)3]2MnF6, and Examples 3 and 4 are for the preparation of manganese-based organic-inorganic hybrid tetramethylammonium fluoromanganate [(CH3)4N]2MnF6.

[0060] Example 1

[0061] 15g of guanidine carbonate was dissolved in 4ml of 49% hydrofluoric acid solution to prepare solution A. Then, 0.6g of K2MnF6 was added to 15ml of 49% hydrofluoric acid solution and stirred until completely dissolved to prepare solution B. Solution A was then added to solution B and stirred for 30 minutes. Finally, the mixture was allowed to stand, aged, and the precipitated sample was collected. After washing three times with acetone or ethanol, the sample was dried at 60℃ for 4 hours to obtain the organic-inorganic hybrid guanidine fluoromanganate [C(NH2)3]2MnF6 material.

[0062] Figure 1 The XRD powder diffraction pattern of the organic-inorganic hybrid guanidine fluoromanganate [C(NH2)3]2MnF6 material prepared in Example 1 is shown. The diffraction peaks of the sample correspond one-to-one with the standard card patterns of the isomorphic [C(NH2)3]2GeF6 in the PDF card library. No diffraction peak signals of any impurity phases were observed, which indicates that the synthesized organic-inorganic hybrid guanidine fluoromanganate [C(NH2)3]2MnF6 material sample is a pure phase.

[0063] Example 2

[0064] Weigh 500g of guanidine carbonate and 5g of KMnO4 and dissolve them in 300ml of 49% hydrofluoric acid solution. Stir until all the solids are dissolved, and then cool the mixed solution to 0℃ using an ice bath. Then, gradually add 30% hydrogen peroxide solution until the solution changes from purple to orange-yellow and stop adding immediately. Let it stand, age, and collect the precipitate sample. Wash it three times with glacial acetic acid, acetone or ethanol, and dry it at 60℃ for 4 hours to obtain the organic-inorganic hybrid guanidine fluoromanganate [C(NH2)3]2MnF6 material.

[0065] The [C(NH2)3]2MnF6 prepared by this method is consistent with that in Example 1.

[0066] Example 3

[0067] Weigh 600g of tetramethylammonium fluoride and 10g of KMnO4 and dissolve them in 500ml of 49% hydrofluoric acid solution. Stir until all the solids are dissolved, and then cool the mixed solution to 0℃ using an ice bath. Then, gradually add 30% hydrogen peroxide solution until the solution changes from purple to orange-yellow, and stop adding immediately. Let it stand, age, and collect the precipitate sample. Wash it three times with glacial acetic acid, acetone or ethanol, and dry it at 60℃ for 4 hours to obtain the [(CH3)4N]2MnF6 organic-inorganic hybrid fluoromanganate polycrystalline powder red fluorescent material.

[0068] Furthermore, the obtained [(CH3)4N]2MnF6 polycrystalline powder material can be converted into a single-crystal material. Weigh 2g of [(CH3)4N]2MnF6 and dissolve it in 15ml of a 49% HF solution. Then add 70g of tetramethylammonium fluoride and heat the solution to 90°C using a water bath or oil bath to make it a hot saturated solution. After cooling to room temperature, the corresponding [(CH3)4N]2MnF6 red fluorescent single-crystal crystal can be obtained.

[0069] Example 4

[0070] 120g of tetramethylammonium fluoride was dissolved in 10ml of 49% hydrofluoric acid solution to prepare solution A. Then, 1g of K2MnF6 was added to 15ml of 49% hydrofluoric acid solution and stirred until completely dissolved to prepare solution B. Solution A was then added to solution B and stirred for 30 minutes. Finally, the mixture was allowed to stand, aged, and the precipitate was collected. The precipitate was washed three times with glacial acetic acid, acetone, or ethanol and dried at 60℃ for 4 hours to obtain the red fluorescent material [(CH3)4N]2MnF6 organic-inorganic hybrid fluoromanganate polycrystalline powder.

[0071] Furthermore, the obtained [(CH3)4N]2MnF6 powder material can be converted into a single crystal material. Weigh 2g of [(CH3)4N]2MnF6 and dissolve it in 20ml of 49% HF solution, then add 50g of tetramethylammonium fluoride, heat to 90℃ in a water bath or oil bath to make it a hot saturated solution, and then let it cool to room temperature to obtain the corresponding [(CH3)4N]2MnF6 red fluorescent single crystal.

[0072] The [(CH3)4N]2MnF6 prepared by this method is consistent with that in Example 3.

[0073] Examples 5-23 illustrate the preparation of Mn with superior luminescence properties using organic-inorganic hybrid fluoromanganate as the manganese source. 4+ Activate red fluorescent materials containing fluorine (oxygen) compounds.

[0074] Example 5

[0075] Using the organic-inorganic hybrid tetramethylammonium fluoromanganate [(CH3)4N]2MnF6 polycrystalline powder prepared in Example 4 as the manganese source, K2SiF6:Mn was prepared by co-precipitation method. 4+ The process for producing red fluorescent materials includes the following steps:

[0076] Measure 2 ml of H₂SiF₆ and add it to 8 ml of 49% hydrofluoric acid solution. Then add 0.1586 g of [(CH₃)₄N]₂MnF₆ and stir for 5 minutes. Next, add 0.6 g of KF and continue stirring for 30 minutes. Collect the precipitate by centrifugation, wash three times with glacial acetic acid, acetone, or ethanol, and dry at 60°C for 4 hours to obtain K₂SiF₆:MnF₆. 4+ Red fluorescent material.

[0077] Appendix Figure 2 The image shows K2SiF6:Mn prepared using an organic-inorganic hybrid fluoromanganate as the manganese source. 4+ The XRD powder diffraction pattern of the red fluorescent material shows that the diffraction peaks of the sample are consistent with the standard K2SiF6 pattern, and no diffraction peak signals of any impurity phases were observed. This indicates that the synthesized K2SiF6:Mn 4+ The red fluorescent material sample is a pure phase.

[0078] Appendix Figure 3 The image shows K2SiF6:Mn 4+The room-temperature excitation and emission spectra of the red fluorescent material sample were obtained. The sample exhibits a strong and broad excitation band in the ultraviolet and near-ultraviolet region (320 nm–420 nm) and the blue light region (420 nm–500 nm). Under 450 nm blue light excitation, the sample emits a narrow band of red light at 630 nm (the strongest emission peak), consisting of multiple sharp peaks, with CIE color coordinates of x = 0.6944, y = 0.3055, and a color purity close to 100%.

[0079] Example 6

[0080] Using the organic-inorganic hybrid guanidine fluoromanganate [C(NH2)3]2MnF6 polycrystalline powder prepared in Example 1 as the manganese source, K2SiF6:Mn was prepared by cation exchange method. 4+ The process for producing red fluorescent materials includes the following steps:

[0081] (1) Preparation of K2SiF6 matrix precursor: 2 ml of H2SiF6 was added to 8 ml of 49% hydrofluoric acid solution, followed by 0.6 g of KF and stirring for 30 minutes. The precipitated sample was collected by centrifugation, washed three times with glacial acetic acid, acetone or ethanol, and dried at 60°C for 4 hours to obtain K2SiF6 matrix.

[0082] (2) K2SiF6:Mn 4+ Preparation of red fluorescent material: Weigh 0.1446 g of [C(NH2)3]2MnF6 and dissolve it in 2 ml of 49% hydrofluoric acid solution. Then add 1.1 g of K2SiF6 matrix precursor and stir continuously for 60 minutes. Collect the precipitate sample by centrifugation, wash it three times with glacial acetic acid, acetone or ethanol, and dry it at 60℃ for 4 hours to obtain K2SiF6:Mn 4+ Red fluorescent material.

[0083] K2SiF6:Mn prepared by ion exchange method 4+ The structure and luminescence properties of the red fluorescent material are the same as those in Example 5.

[0084] Examples 7 to 23

[0085] Except for weighing or measuring the relevant raw materials according to their chemical formula composition and stoichiometry, the other preparation steps are the same as in Example 5. The chemical formula composition, excitation light absorption efficiency, fluorescence lifetime and relative brightness of the sample are shown in Table 1 below.

[0086] To demonstrate the advantages of this invention, the organic-inorganic hybrid fluoromanganate used in this invention was replaced with all-inorganic fluoromanganate, manganate, or permanganate as the tetravalent manganese source to synthesize fluoride (oxide) red fluorescent materials as a corresponding comparative example. During the replacement, the molar number of manganese used (10 mol%) was kept consistent. Then, the corresponding fluoride (oxide) red fluorescent materials were prepared according to the same synthesis steps as in the examples. The luminescence performance of the fluoride (oxide) red fluorescent materials prepared in the examples and comparative examples was tested at the same time, under the same test environment and test conditions, including luminescence brightness (efficiency) and fluorescence lifetime.

[0087] Appendix Figure 4 The image shows K2SiF6:Mn prepared using organic-inorganic hybrid tetramethylammonium fluoromanganate as the manganese source. 4+ Red fluorescent materials and K2SiF6:Mn prepared using K2MnF6, Cs2MnF6, Rb2MnF6, KMnO4, and Na2MnO4 as manganese sources. 4+ Comparison of emission spectral intensities of red fluorescent material samples. Under blue light excitation, all samples emitted narrow-band red light composed of multiple sharp peaks. Among them, K2SiF6:Mn prepared using organic-inorganic hybrid tetramethylammonium fluoromanganate as the manganese source showed the most significant emission. 4+ The luminescence brightness (efficiency) of the sample was significantly higher than that of K2SiF6:Mn prepared using K2MnF6 (Comparative Example 1), Cs2MnF6 (Comparative Example 3), Rb2MnF6 (Comparative Example 4), KMnO4 (Comparative Example 5), and Na2MnO4 (Comparative Example 6) as manganese sources. 4+ sample.

[0088] Appendix Figure 5 The image shows [(CH3)4N]2GeF6:Mn prepared using organic-inorganic hybrid tetramethylammonium fluoromanganate as the manganese source. 4+ Red fluorescent material (Example 20) and [(CH3)4N]2GeF6:Mn prepared using K2MnF6 as the manganese source 4+ Comparison of emission spectral intensities of red fluorescent materials (Comparative Example 20). Under blue light excitation, all samples emitted narrow-band red light composed of multiple sharp-line peaks. Among them, [(CH3)4N]2GeF6:Mn prepared using organic-inorganic hybrid tetramethylammonium fluoromanganate as the manganese source... 4+ The luminescence brightness (efficiency) of the sample was significantly higher than that of [(CH3)4N]2GeF6:Mn prepared using K2MnF6 as the manganese source. 4+ sample.

[0089] Appendix Figure 6 The image shows Cs₂NbOF₅:Mn prepared using organic-inorganic hybrid tetramethylammonium fluoromanganate as the manganese source. 4+Red fluorescent material (Example 23) and Cs2NbOF5:Mn prepared using K2MnF6 as the manganese source 4+ Comparison of emission spectral intensities of red fluorescent materials (Comparative Example 23). Under blue light excitation, all samples emitted narrow-band red light composed of multiple sharp-line peaks. Among them, Cs₂NbOF₅:Mn prepared using organic-inorganic hybrid tetramethylammonium fluoromanganate as the manganese source... 4+ The luminescence brightness (efficiency) of the sample was significantly higher than that of Cs2NbOF5:Mn prepared using K2MnF6 as the manganese source. 4+ sample.

[0090] According to the above liquid-phase method, Mn2 was synthesized using the organic-inorganic hybrid fluoromanganate precursor materials [(CH3)4N]2MnF6 or [C(NH2)3]2MnF6 of this application as the tetravalent manganese source. 4+ The activated fluoride (oxygen) red fluorescent material exhibits superior performance compared to the fluoride (oxygen) red fluorescent materials synthesized using previously reported all-inorganic fluoromanganate, manganate, and permanganate as tetravalent manganese sources in terms of excitation light absorption efficiency and fluorescence quantum yield (luminescence intensity). Specifically, it has higher excitation light absorption efficiency and higher luminescence intensity.

[0091] Table 1 below compares the optical properties of some typical manganese-activated fluoride (oxide) red fluorescent materials synthesized using the synthesized organic-inorganic hybrid fluoromanganate precursor materials [(CH3)4N]2MnF6 or [C(NH2)3]2MnF6 as tetravalent manganese sources with those synthesized using all-inorganic fluoromanganate, permanganate or manganate as tetravalent manganese sources, including excitation light absorption efficiency, fluorescence lifetime, and relative brightness.

[0092] Table 1

[0093] Examples 5-23 compare the excitation light absorption efficiency, fluorescence lifetime, and relative brightness of some typical manganese-activated fluoride (oxide) red fluorescent materials synthesized using organic-inorganic hybrid fluoromanganate precursor materials [(CH3)4N]2MnF6 or [C(NH2)3]2MnF6 as tetravalent manganese sources with those synthesized using all-inorganic fluoromanganate, permanganate, or manganate as tetravalent manganese sources.

[0094]

[0095]

[0096] Note: All the above data were obtained under the same test conditions at the optimal blue light excitation wavelength of the material; the manganese content (in Example 5, the molar percentage of manganese to the total manganese and silicon) and the amount of alkali metal from the manganese source (the amount of alkali metal from the precursor manganese source in the synthesized material, in Comparative Example 3, the Cs content) in the synthesized material were measured by inductively coupled plasma optical emission spectrometry (ICP-OES). The manganese content represents the molar percentage of manganese to the matrix, and the unit of the amount of alkali metal from the manganese source is moles per liter. Blank parts indicate that no test was performed; the molar percentage of tetravalent manganese content in the luminescent center to the total manganese content in the synthesized material was obtained by X-ray photoelectron spectroscopy (XPS) analysis. Blank parts indicate that no test was performed.

[0097] As can be seen from Table 1, the Mn synthesized using the organic-inorganic hybrid fluoromanganate [(CH3)4N]2MnF6 or [C(NH2)3]2MnF6 of this application as tetravalent manganese source precursors... 4+ Compared with the red fluorescent materials of fluoride (oxygen) activated by using the previously reported all-inorganic fluoromanganate, permanganate or manganate as tetravalent manganese source precursors, the red fluorescent materials of fluoride (oxygen) activated by fluoride ...

[0098] Table 1 shows the various Mn values ​​in the comparative examples. 4+ The method for synthesizing activated fluoride (oxygen) red fluorescent materials is as follows.

[0099] Comparative examples of various Mn 4+ The synthesis method for activating red fluorescent materials of fluoride (oxygen) compounds is consistent with the steps in the examples, except that the equimolar number (equimolar manganese content 10 mol%) of organic-inorganic hybrid fluoromanganate is replaced with all-inorganic fluoromanganate, manganate, and permanganate as tetravalent manganese sources.

[0100] Comparative Example 1

[0101] Red fluorescent material K2SiF6:Mn 4+ The synthesis method is as follows:

[0102] Measure 2 ml of H₂SiF₆ and add it to 8 ml of 49% hydrofluoric acid solution. Then add 0.1236 g of K₂MnF₆ and stir for 5 minutes. Next, add 0.6 g of KF and continue stirring for 30 minutes. Collect the precipitate by centrifugation, wash three times with glacial acetic acid, acetone, or ethanol, and dry at 60°C for 4 hours to obtain K₂SiF₆:Mn₆. 4+ Red fluorescent material.

[0103] Comparative Example 2 achieves the same effect as K2SiF6:Mn in Comparative Example 1 by reducing the content of organic-inorganic hybrid fluoromanganate.4 + The manganese content in red fluorescent materials should be as consistent as possible. The synthesis steps are as follows:

[0104] Red fluorescent material K2SiF6:Mn 4+ The synthesis method is as follows:

[0105] Measure 2 ml of H₂SiF₆ and add it to 8 ml of 49% hydrofluoric acid solution. Then add 0.1189 g of [(CH₃)₄N]₂MnF₆ and stir for 30 seconds. Next, add 0.6 g of KF and continue stirring for 30 minutes. Collect the precipitate by centrifugation, wash three times with glacial acetic acid, acetone, or ethanol, and dry at 60°C for 4 hours to obtain K₂SiF₆:MnF₆. 4+ Red fluorescent material.

[0106] Comparative Example 3-22 Mn 4+ The preparation steps for activating red fluorescent fluoride materials are the same as those for Comparative Example 1, except that the relevant raw materials are weighed according to their chemical formula and stoichiometric ratio.

[0107] It should be understood that any modifications, substitutions, or changes made by those skilled in the art based on the true spirit of the present invention and on the specific embodiments thereof should be covered within the protection scope of the present invention.

Claims

1. A type of Mn 4+ A method for preparing activated fluoride or fluoride oxide red fluorescent materials, characterized in that, Using organic-inorganic hybrid fluoromanganate materials as Mn 4+ Source preparation of Mn 4+ Activated red fluorescent materials of fluoride or fluoride oxide; the Mn 4+ The chemical composition of activated fluoride or fluoride oxide red fluorescent materials is: A2M 1-x F6: x Mn 4+ BM 1-x F6: x Mn 4+ A2Q 1-x OF5: x Mn 4+ Where A is Li + Na + K + 、Rb + Cs + (NH4) + [(CH3)4N] + One or more combinations of B, where B is Mg 2+ Ca 2+ 、Sr 2+ Ba 2+ Zn 2+ One or more combinations of Si, where M is Si 4+ 、Ge 4+ Sn 4+ Ti 4+ Zr 4+ Hf 4+ Mn 4+ One or more combinations of Nb, where Q is Nb 5+ Ta 5+ and V 5+ One or more combinations of the following, x For Mn 4+ The molar percentage coefficient relative to M or Q ions, 0 < x ≤ 1.0; The chemical composition of the organic-inorganic hybrid fluoromanganate material is: T2MnF6· x’ H2O; where T is an organic group [C(NH2)3] + [(CH3)4N] + [(CH3CH2)4N] + [(CH3CH2CH2)4N] + [(CH3CH2CH2CH2)4N] + One or more combinations of; x’ The crystal lattice contains water of crystallization, 0 ≤ x’ ≤ 5.

2. The Mn according to claim 1 4+ A method for preparing activated fluoride or fluoride oxide red fluorescent materials, characterized in that, The Mn 4+ Methods for preparing activated red fluorescent materials of fluorides or fluorides include liquid-phase coprecipitation and cation exchange. (1) Prepared by liquid-phase coprecipitation method, including the following steps: Compounds containing M or Q ions are added to HF solution, followed by the addition of an organic-inorganic hybrid fluoromanganate material, and the mixture is stirred for 5-30 minutes. Finally, compounds containing A or B ions are added, and the mixture is stirred for another 5-360 minutes. The resulting precipitate is collected, washed, and dried to obtain the Mn. 4+ Activate red fluorescent materials containing fluorides or fluorides; (2) Prepared by cation exchange method, including the following steps: A compound containing M or Q ions is added to an HF solution, followed by a compound containing A or B ions. The mixture is stirred for 30-360 minutes. The resulting precipitate is collected, washed, and dried to obtain a fluoride or fluoride oxide matrix precursor. Finally, an organic-inorganic hybrid fluoromanganate material is dissolved in an HF aqueous solution, and then the fluoride or fluoride oxide matrix precursor is added. The mixture is stirred continuously for 5-360 minutes. The resulting precipitate is collected, washed, and dried to obtain the Mn. 4+ Activate red fluorescent materials containing fluorides or fluorides.

3. The Mn according to claim 2 4+ A method for preparing activated fluoride or fluoride oxide red fluorescent materials, characterized in that, In the liquid-phase coprecipitation method and the cation exchange method, the compound containing M or Q ions is one or more of the elements, oxides, acids and bases containing M or Q ions; the compound containing A or B ions is one or more of the bases and salts containing A or B ions.

4. The Mn according to claim 3 4+ A method for preparing activated fluoride or fluoride oxide red fluorescent materials, characterized in that, In the liquid-phase coprecipitation method and the cation exchange method, the compound containing M or Q ions is one or a combination of two or more of the following: silicon powder, tin powder, silicon dioxide, germanium oxide, hafnium oxide, titanium oxide, tin oxide, zirconium oxide, niobium oxide, tantalum oxide, fluorosilicic acid, fluorogermanic acid, fluorotitanic acid, fluorozirconic acid, fluorohafnium acid, fluoroniobic acid, fluorotantalic acid, and potassium fluoromanganate; the compound containing A or B ions is lithium hydroxide, potassium hydroxide, sodium hydroxide, rubidium hydroxide, cesium hydroxide, ammonia, tetramethylammonium hydroxide, tetramethylammonium fluoride, tetramethylammonium fluoride tetrahydrate, tetramethylammonium acetate, tetramethylammonium sulfate, lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride, cesium fluoride, ammonium fluoride, lithium hydrofluoride, sodium hydrofluoride, and hydrofluoric acid. Potassium, ammonium fluoride, lithium carbonate, sodium carbonate, potassium carbonate, rubidium carbonate, cesium carbonate, ammonium carbonate, lithium bicarbonate, sodium bicarbonate, potassium bicarbonate, rubidium bicarbonate, cesium bicarbonate, ammonium bicarbonate, lithium bisulfate, sodium bisulfate, potassium bisulfate, rubidium bisulfate, cesium bisulfate, ammonium bisulfate, lithium sulfate, sodium sulfate, potassium sulfate, rubidium sulfate, cesium sulfate, ammonium sulfate, lithium nitrate, sodium nitrate, potassium nitrate, rubidium nitrate, cesium nitrate, ammonium nitrate, lithium phosphate, sodium phosphate, potassium phosphate, rubidium phosphate, cesium phosphate, ammonium phosphate, lithium hydrogen phosphate, sodium hydrogen phosphate, potassium hydrogen phosphate, rubidium hydrogen phosphate, cesium hydrogen phosphate, ammonium hydrogen phosphate, lithium chloride, sodium chloride, potassium chloride, rubidium chloride, cesium chloride, ammonium chloride.

5. The Mn according to claim 1 4+ A method for preparing activated fluoride or fluoride oxide red fluorescent materials, characterized in that, The organic-inorganic hybrid fluoromanganate material is either an organic-inorganic hybrid fluoromanganate polycrystalline powder material or an organic-inorganic hybrid fluoromanganate single crystal material.

6. The Mn according to claim 5 4+ A method for preparing activated fluoride or fluoride oxide red fluorescent materials, characterized in that, The preparation methods of the organic-inorganic hybrid fluoromanganate polycrystalline powder material include liquid phase method 1 and liquid phase method 2; (A) Prepared using liquid phase method 1, including the following steps: The compound containing the organic group T, permanganate or manganate are added together to the HF solution and stirred to dissolve. Then, H2O2 aqueous solution is added dropwise until the solution changes color and an orange-yellow precipitate is produced. After aging, filtration, washing and drying, the organic-inorganic hybrid fluoromanganate polycrystalline powder material is obtained. (B) Prepared using liquid phase method 2, including the following steps: Mn-containing 4+ The fluoride is added to the HF solution and stirred to dissolve it. Then, a compound containing an organic group T is added and stirring is continued for 5-360 minutes. The resulting precipitate is washed and dried to obtain the organic-inorganic hybrid fluoromanganate polycrystalline powder material. The preparation method of the organic-inorganic hybrid fluoromanganate single crystal material includes the following steps: The organic-inorganic hybrid fluoromanganate polycrystalline powder material is dissolved in HF solution, tetramethylammonium fluoride is added, and the solution is heated to make it a hot saturated solution. Then it is cooled to room temperature to obtain the organic-inorganic hybrid fluoromanganate single crystal material.

7. The Mn according to claim 6 4+ A method for preparing activated fluoride or fluoride oxide red fluorescent materials, characterized in that, The compound containing the organic group T mentioned in liquid phase method 1 is one containing [C(NH2)3]. + [(CH3)4N] + [(CH3CH2)4N] + [(CH3CH2CH2)4N] + [(CH3CH2CH2CH2)4N] + One or more combinations of halides, acids, bases and salts; In liquid phase method 1, the permanganate or manganate is one or a combination of two or more of LiMnO4, NaMnO4, KMnO4, Ca(MnO4)2, Li2MnO4, Na2MnO4, K2MnO4, and Mg(MnO4)2; the addition of H2O2 aqueous solution is carried out at 0 ~ 5 ℃. The compound containing the organic group T mentioned in liquid phase method 2 is one containing [C(NH2)3]. + [(CH3)4N] + [(CH3CH2)4N] + [(CH3CH2CH2)4N] + [(CH3CH2CH2CH2)4N] + One or more combinations of halides, acids, bases and salts; The Mn-containing liquid phase method 2 4+ The fluoride is one or a combination of two or more of Li2MnF6, Na2MnF6, K2MnF6, Rb2MnF6, Cs2MnF6, and (NH4)2MnF6.

8. The Mn according to claim 7 4+ A method for preparing activated fluoride or fluoride oxide red fluorescent materials, characterized in that, The compounds containing the organic group T mentioned in liquid phase method 1 and liquid phase method 2 are one or more of the following: guanidine carbonate, guanidine hydrochloride, tetramethylammonium fluoride, tetramethylammonium fluoride tetrahydrate, tetramethylammonium acetate, tetramethylammonium sulfate, tetramethylammonium hydroxide, tetraethylammonium fluoride, tetrapropylammonium fluoride, and tetrabutylammonium fluoride.

9. Mn prepared by the preparation method according to any one of claims 1-8 4+ Activate red fluorescent materials containing fluorides or fluorides.

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