Mn 4+ Activation of high-entropy fluoride red luminescent materials and preparation method and application thereof

Abstract

This application belongs to the field of luminescent materials technology, and particularly relates to a Mn 4+ Activated high-entropy fluoride red luminescent materials, their preparation methods, and applications. Including materials with the molecular formula A2X. 1‑y F6:yMn 4+ BX 1‑ y F6:yMn 4+ C3X 1‑y F6:yMn 4+ D2X 1‑y F7:yMn 4+ At least one luminescent material, wherein the A-site, C-site, and D-site are each independently selected from NH4. + Li + Na + K + 、Rb + Cs + (CH3)4N + At least one of the following: B site is selected from Ba and / or Zn; each luminescent material contains at least four metal elements at the X site, with the molar ratio of each metal element ranging from 5% to 35%, and y in each luminescent material independently satisfies 0 < y < 0.5. Through compositional design, the high-entropy fluoride matrix exhibits high disorder and large lattice distortion, which is Mn 4+ It provides a low-symmetry lattice environment, enhances radiative transitions, and significantly improves the luminescence efficiency and optical performance of various luminescent materials.

Description

Technical Field

[0001] This application belongs to the field of luminescent materials technology, and particularly relates to a Mn 4+ Activated high-entropy fluoride red luminescent materials, their preparation methods, and applications. Background Technology

[0002] White light-emitting diodes (LEDs) are considered a new generation of solid-state lighting sources due to their advantages such as energy efficiency, environmental friendliness, long lifespan, and ease of integration into intelligent lighting systems. They have replaced inefficient incandescent lamps and traditional fluorescent lamps containing harmful mercury, and have broad application prospects in lighting, display, and other fields. Red phosphor is a key material that determines the color quality of white LEDs and has important application value in high-end warm white lighting and wide color gamut displays.

[0003] Currently, there are two main types of mainstream red phosphor systems: one is based on M2Si5N8:Eu 2+ and MSiAlN3:Eu 2+ Eu (M = Ca, Sr, Ba) 2+ Doped nitride red LEDs generally possess high quantum efficiency, excellent thermal stability, and chemical stability. However, their preparation conditions are demanding (requiring high temperature, high nitrogen pressure, and expensive raw materials), resulting in broadband emission, with most emission wavelengths exceeding 650nm, outside the human eye's sensitive region, thus affecting the LED's lumen efficiency and color gamut. Another type is based on A2XF6:Mn... 4+ and A3YF6:Mn 4+ Mn, represented by (A = NH4, Na, K, Cs, Rb; X = Ti, Si, Ge, Sn; Y = Ga, Al, Sc), etc. 4+ Doped fluoride red powder. Compared to the former's stringent synthesis conditions, Mn 4+ Doped fluoride red light is simple to synthesize and can be produced using various methods; it also employs the transition metal Mn as an activator, resulting in low cost. Furthermore, it exhibits efficient narrowband red light emission and broadband blue light absorption, with its emission spectrum falling within the human eye's sensitivity curve. However, in practical applications, Mn... 4+ There is a pressing problem to be solved with activated fluoride red phosphors, namely Mn 4+ The parity-forbidden dd electron transitions result in a relatively low transition rate and low luminescence efficiency, especially absorption efficiency, which makes it difficult to improve the external quantum efficiency.

[0004] Solid solution regulation is an effective means to improve the performance of fluoride phosphors and has been widely reported and studied. However, this strategy is mainly based on binary solid solutions, with limited solid solution components and solubility, restricted regulation space, and insufficient development potential. It has not been very effective in improving the external quantum efficiency of fluoride red phosphors. SUMMARY

[0005] The application aims to provide a Mn 4+ The application discloses an activated high-entropy fluoride red luminescent material, a preparation method and application thereof, and aims to solve the problem of low external quantum efficiency of existing fluoride red fluorescent powder.

[0006] To achieve the above purposes, the application adopts the following technical solutions:

[0007] In a first aspect, the application provides a Mn 4+ The application discloses an activated high-entropy fluoride red luminescent material, a preparation method and application thereof, and aims to solve the problem of low external quantum efficiency of existing fluoride red fluorescent powder. 1-y F6:yMn 4+ , BX 1-y F6:yMn 4+ , C3X 1-y F6:yMn 4+ , D2X 1-y F7:yMn 4+ , wherein A, C and D are independently selected from at least one of NH4 + , Li + , Na + , K + , Rb + , Cs + , (CH3)4N + ; B is selected from Ba and / or Zn; X in each of the luminescent materials independently comprises at least four metal elements, and the molar ratio of each metal element is in the range of 5% to 35%; and y in each of the luminescent materials independently satisfies 0

[0008] In some possible implementation manners, y in each of the luminescent materials independently satisfies 0.01≤y≤0.30.

[0009] In some possible implementation manners, X in each of the luminescent materials independently comprises at least four metal elements selected from Mg, Zn, Al, Ga, Sc, In, Si, Ti, Ge, Sn, Zr, Hf, Nb, Ta, Sb, W, Mo and Te.

[0010] In some possible implementation manners, A, C and D are independently selected from K + or Cs + .

[0011] In some possible implementation manners, B is selected from Ba and / or Zn.

[0012] In some possible implementation manners, the X position in each of the light emitting materials comprises four, five or six metal elements, and each metal element is in an equimolar ratio or a molar ratio within a range from 5% to 35%.

[0013] In some possible implementation manners, the C3X 1-y F6:yMn 4+ In the formula, the A position is K, and the X position comprises four elements of Al, Ga, Sc and In.

[0014] In some possible implementation manners, the A2X 1-y F6:yMn 4+ In the formula, the A position is K, and the X position comprises four elements of Si, Ge, Nb and Ga.

[0015] In some possible implementation manners, the A2X 1-y F6:yMn 4+ In the formula, the A position is K, and the X position comprises five elements of Si, Ti, Ge, Nb and Al.

[0016] In some possible implementation manners, the A2X 1-y F6:yMn 4+ In the formula, the A position is Cs, and the X position comprises four elements of Si, Ti, Ge and Zr.

[0017] In some possible implementation manners, the A2X 1-y F6:yMn 4+ In the formula, the A position is Cs, and the X position comprises five elements of Si, Ti, Ge, Ta and Al.

[0018] In some possible implementation manners, the BX 1-y F6:yMn 4+ In the formula, the B position is Ba, and the X position comprises five elements of Si, Ti, Ge, Sn and Hf.

[0019] In some possible implementation manners, the D2X 1-y F7:yMn 4+ In the formula, the D position is K, and the X position comprises four elements of Si, Ta, Nb and Mo.

[0020] In some possible implementation manners, the D2X 1-y F7:yMn 4+ In the formula, the D position is K, and the X position comprises six elements of Si, Ge, Ta, Nb, W and Mo.

[0021] In some possible implementation manners, the red light emitting material comprises K3(Al 0.25 ,Ga 0.25 ,In 0.25 ,Sc0.25 ) 0.97 F6: 0.03 Mn 4+ , K3(Al 0.30 , Ga 0.30 , In 0.15 , Sc 0.15 , Zn 0.05 , Si 0.05 ) 0.97 F6: 0.03 Mn 4+ , K2(Si 0.25 , Ge 0.25 , Nb 0.25 , Ga 0.25 ) 0.93 F6: 0.07 Mn 4+ , K2(Si 0.20 , Ge 0.20 , Ti 0.20 , Nb 0.20 , Al 0.20 ) 0.95 F6: 0.05 Mn 4+ , Cs2(Si 0.25 , Ge 0.25 , Ti 0.25 , Zr 0.25 ) 0.90 F6: 0.10 Mn 4+ , Cs2(Si 0.35 , Ge 0.35 , Ti 0.20 , Ta 0.05 , Al 0.05 ) 0.90 F6: 0.10 Mn 4+ , Ba(Si 0.30 , Ge 0.30 , Ti 0.20 , Sn 0.10 , Hf 0.10 ) 0.97 F6: 0.03 Mn 4+ , K2(Si 0.15 , Nb 0.35 , Ta 0.35 , W 0.15 ) 0.96 F7: 0.04 Mn 4+ , K2(Si 0.10 , Ge 0.10 , Nb 0.35 , Ta 0.35 , W 0.05 , Mo 0.05 ) 0.97 F7: 0.03 Mn 4 +at least one of the following: Mn

[0022] In a second aspect, the present application provides a Mn 4+ A preparation method of an activated high-entropy fluoride red luminescent material, comprising the following steps:

[0023] The Mn 4+ Obtaining raw material components according to the stoichiometric ratio of each metal element in the X position of the chemical formula of the activated high-entropy fluoride red luminescent material;

[0024] Mixing the raw material components with HF, and then performing a hydrothermal reaction, adding a manganese source and a precipitant, and sequentially performing mixing treatment and a solvothermal reaction after cooling, to obtain a Mn 4+ An activated high-entropy fluoride red luminescent material.

[0025] In some possible implementation manners, the substance type of the raw material components includes at least one of the following: an oxide, a fluoride, and a metal salt.

[0026] In some possible implementation manners, the purity of the raw material components is not less than 99%.

[0027] In some possible implementation manners, the manganese source includes K2MnF6.

[0028] In some possible implementation manners, the precipitant includes the Mn 4+ At least one of the following: a fluoride, a hydrofluoride, and a metal salt corresponding to the elements in the A position, the B position, the C position, and the D position in the activated high-entropy fluoride red luminescent material.

[0029] In some possible implementation manners, the ratio of the added amount of the HF to the raw material components is (1-10) mL: 1 g.

[0030] In some possible implementation manners, the concentration of the HF is 10%-49%.

[0031] In some possible implementation manners, the conditions of the hydrothermal reaction include: reacting in a high-pressure reaction kettle at a temperature of 100-200 ℃ for 1-8 h.

[0032] In some possible implementation manners, the step of the mixing treatment includes: after adding the manganese source to dissolve, adding the HF solution of the precipitant dropwise, and stirring at room temperature for 10-30 min.

[0033] In some possible implementation manners, the conditions of the solvothermal reaction include: reacting in a high-pressure reaction kettle at a temperature of 50-100 ℃ for 1-5 h.

[0034] In some possible implementation manners, after the solvothermal reaction, the reaction product is collected after separation and cooling to room temperature, and then is washed and dried at a temperature of 50-85 DEG C for 4-12 hours.

[0035] In some possible implementation manners, the precipitant comprises at least one of KHF2, KF, K2CO3 and KNO3.

[0036] In a third aspect, the present application provides a light emitting diode comprising the Mn 4+ The high-entropy fluoride red luminescent material or the Mn 4+ The high-entropy fluoride red luminescent material.

[0037] In some possible implementation manners, the light emitting diode comprises the red luminescent material and the yellow luminescent material in a mass ratio of 2:1.

[0038] In some possible implementation manners, the light emitting diode comprises the red luminescent material and the green luminescent material in a mass ratio of 1:1.

[0039] In some possible implementation manners, the light emitting diode is excited by a blue light chip.

[0040] The red luminescent material provided in the first aspect of the present application is a high-entropy system, which is composed of four or more elements in a near-molar ratio. The selectivity and diversity of the structure, composition and proportion of the high-entropy fluoride red luminescent material expand the design range of the red luminescent material and enrich the development space of the red luminescent material. Meanwhile, the high-entropy fluoride red luminescent material has high configuration entropy, which can inhibit the phase separation tendency of the material and easily obtain a single-structure high-entropy solid solution phase. In addition, due to the high disorder and severe lattice distortion effect, the high-entropy fluoride red luminescent material can provide a low-symmetry lattice environment for the activated ions, which helps to improve the luminescent efficiency and performance of the Mn 4+ The high-entropy fluoride red luminescent material activated by the Mn 4+ The design of the components of the A site, the B site, the C site or the D site, and the X site in the high-entropy fluoride red luminescent material activated by the Mn 4+ The design of the components of the A site, the B site, the C site or the D site, and the X site in the high-entropy fluoride red luminescent material activated by the Mn 4+ The design of the components of the A site, the B site, the C site or the D site, and the X site in the high-entropy fluoride red luminescent material activated by the Mn

[0041] The Mn 4+ The preparation method of the high-entropy fluoride red luminescent material activated by the Mn 4+The stoichiometric ratio of each metal element in the X position in the chemical formula of the activated high-entropy fluoride red luminescent material is obtained after the raw material components are mixed with HF to perform a hydrothermal reaction, and then a manganese source and a precipitating agent are added to perform a solvothermal reaction, so that Mn 4+ is doped into the fluoride matrix material, and the product is precipitated by a precipitating agent to obtain Mn 4+ The activated high-entropy fluoride red luminescent material is prepared. The preparation process is simple and easy to operate, and is suitable for industrial large-scale production and application. The prepared high-entropy fluoride red luminescent material is designed by composition, so that the high-entropy fluoride matrix has high disorder and large lattice distortion, which provides a low-symmetry lattice environment for Mn 4+ , enhances the radiation transition, and significantly improves the luminescent efficiency and optical performance of each luminescent material.

[0042] In the light-emitting diode of the present application, the Mn 4+ The activated high-entropy fluoride red luminescent material can be used to prepare an LED device with high lumens efficiency, high color rendering index, and low correlated color temperature after being mixed with other color luminescent materials, thereby improving the luminescent efficiency of the light-emitting diode. BRIEF DESCRIPTION OF DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0044] Figure 1 is the Mn 4+ The flowchart of the preparation method of the activated high-entropy fluoride red luminescent material is shown in the figure.

[0045] Figure 2 is the spectral diagram in the quantum efficiency test provided by the embodiments of the present application;

[0046] Figure 3 is the morphology and element distribution diagram of the high-entropy fluoride red luminescent material provided by the embodiment 3 of the present application;

[0047] Figure 4 is the emission spectrum diagram of the high-entropy fluoride red luminescent material provided by the embodiment 3 of the present application;

[0048] Figure 5 is the Raman spectrum diagram of the high-entropy fluoride red luminescent material and the red luminescent material of the comparative example 2 provided by the embodiment 3 of the present application;

[0049] Figure 6XRD diffraction patterns of the high-entropy fluoride red luminescent materials provided in Examples 3-8 of this application;

[0050] Figure 7 Emission spectra of the high-entropy fluoride red luminescent materials provided in Examples 3-8 of this application;

[0051] Figure 8 The excitation and emission spectra of the high-entropy fluoride red luminescent material provided in Example 10 of this application;

[0052] Figure 9 Excitation and emission spectra of the high-entropy fluoride red luminescent material provided in Example 11 of this application;

[0053] Figure 10 This is the electroluminescence spectrum of a white LED device encapsulated with a high-entropy fluoride red luminescent material and commercial yellow phosphor, as provided in Embodiment 3 of this application.

[0054] Figure 11 This is the electroluminescence spectrum of a white LED device encapsulated from a high-entropy fluoride red luminescent material and commercial green phosphor provided in Embodiment 3 of this application. Detailed Implementation

[0055] To make the technical problems, technical solutions, and beneficial effects of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0056] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0057] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b or c", or "at least one of a, b and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0058] It should be understood that the size of the serial number of the above processes does not mean the order of execution, and part or all of the steps can be executed in parallel or in sequence, and the execution order of the processes should be determined according to their functions and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0059] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a" and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0060] The weight of the related components mentioned in the embodiments of the present application can not only refer to the specific content of each component, but also represent the weight ratio relationship between each component, therefore, as long as the content of the related components in the embodiments of the present application is enlarged or reduced in proportion, it is within the scope disclosed in the embodiments of the present application. Specifically, the mass in the embodiments of the present application can be μg, mg, g, kg and other mass units commonly known in the chemical field.

[0061] The terms "first", "second" are only for the purpose of description, used to distinguish objects such as substances from each other, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. For example, without departing from the scope of the embodiments of the present application, the first XX can also be called the second XX, and similarly, the second XX can also be called the first XX. Therefore, the features limited by "first" and "second" can explicitly or implicitly include one or more of the features.

[0062] The first aspect of the embodiments of the present application provides a Mn 4+ The high-entropy fluoride red luminescent material is activated, including at least one luminescent material with a molecular formula of A2X 1-y F6:yMn 4+ , BX 1-y F6:yMn 4+ , C3X 1-y F6:yMn 4+ , D2X 1-y F7:yMn 4+ , wherein A, C and D are independently selected from NH4 + , Li + , Na + , K + , Rb + , Cs + , (CH3)4N +At least one of the following; the B site is selected from Ba and / or Zn; the X site in each luminescent material independently includes at least four metal elements, and the molar ratio of each metal element is in the range of 5% to 35%, and the y in each luminescent material independently satisfies 0 < y < 0.5.

[0063] The first aspect of the embodiments of this application provides a red luminescent material comprising a molecular formula A2X. 1-y F6:yMn 4+ BX 1-y F6:yMn 4+ C3X 1-y F6:yMn 4+ D2X 1-y F7:yMn 4+ At least one luminescent material is selected, with 0 < y < 0.5, to avoid excessive manganese ion doping that could damage the luminescent material structure. This ensures that these materials are all high-entropy systems, composed of four or more metal elements in near-molar or equimolar ratios. The selectivity and diversity of their structure, composition, and proportion expand the range of red luminescent material composition design and enrich the development space of red luminescent materials. Simultaneously, high-entropy fluoride red luminescent materials possess high configurational entropy, which can suppress the phase separation tendency of materials and easily obtain a single-structure high-entropy solid solution phase. Furthermore, due to their high disorder and severe lattice distortion effect, they can provide a low-symmetry lattice environment for activating ions, which helps to improve the Mn... 4+ This application describes the activation of high-entropy fluoride red luminescent materials to improve luminous efficiency and performance. The embodiments of this application involve the activation of Mn... 4+ The compositional design of the A, B, C or D sites, and X sites in the activated high-entropy fluoride red luminescent material aims to ensure that the radii of the principal ions are as close as possible, the electronegativity of the elements are similar, the charges at the lattice sites are balanced, and the crystal structures of the matrix corresponding to each element are similar. The designed high-entropy fluoride matrix exhibits high disorder and large lattice distortion, and can be used for Mn... 4+ Providing a low-symmetry lattice environment helps enhance radiative transitions, significantly improving the luminescence efficiency and optical performance of various luminescent materials.

[0064] This application's embodiment Mn 4+ In activated high-entropy fluoride red luminescent materials, each luminescent material independently includes at least four metal elements at the X-position, with each metal element having a near-molar ratio or equimolar ratio, and the molar ratio of each metal element being within the range of 5% to 35%. That is, when there are four metal elements at the X-position, the molar ratio of the four metal elements is close to or equal to 25%:25%:25%:25%; when there are five metal elements at the X-position, the molar ratio of the five metal elements is close to or equal to 20%:20%:20%:20%:20%, and so on.

[0065] In some possible implementations, y in each luminescent material independently satisfies 0.01≤y≤0.30. In this case, the designed high-entropy fluoride red luminescent material matrix has better high disorder and lattice distortion, which can provide Mn 4+ The lattice environment with lower symmetry helps to enhance the radiation transition, and better improve the luminescent efficiency of the high-entropy fluoride red luminescent material. For example, y can be 0.01, 0.02, 0.03, etc. typical but non-limiting point values or interval values between any two point values.

[0066] In some possible implementations, the X site in each luminescent material respectively independently includes at least four metal elements selected from Mg, Zn, Al, Ga, Sc, In, Si, Ti, Ge, Sn, Zr, Hf, Nb, Ta, Sb, W, Mo, and Te. These metal elements are beneficial to make the ionic radius of each host element close, the electronegativity of the elements similar, the charge of the lattice site balanced, and the crystal structure of each element corresponding to the matrix similar. Thus, it is beneficial to make the high-entropy fluoride matrix have high disorder and large lattice distortion, which can provide Mn 4+ The lattice environment with lower symmetry helps to enhance the radiation transition, and significantly improves the luminescent efficiency and optical performance of each luminescent material.

[0067] In some possible implementations, the X site in each luminescent material includes four, five or six metal elements, and each metal element is in an equimolar ratio or a molar ratio in the range of 5% to 35%. When each metal element is in an equimolar ratio, each metal element in the X site of each luminescent material has the same molar proportion.

[0068] In some embodiments, the ionic radius of each metal element in the X site should be as close as possible, the electronegativity of the elements similar, the charge of the lattice site balanced, the crystal structure of each element corresponding to the matrix similar, and the molar ratio of each element close to the same proportion and in the range of 5% to 35%. For example, when the X site includes four metal elements, the equimolar ratio of each metal element is 25%:25%:25%:25%; when the X site includes five metal elements, the equimolar ratio of each metal element is 20%:20%:20%:20%:20%.

[0069] In some possible implementations, the A site, the C site and the D site are respectively and independently selected from K + or Cs + .

[0070] In some possible implementations, the B site is selected from Ba and / or Zn.

[0071] In the above embodiments of the present application, different choices of A, C, D, B and X positions will construct high-entropy fluoride red luminescent materials of different chemical formulas. X position can be composed of four or more elements of the same valence or different valence. The structure and element selection are diverse. The doping concentration of Mn 4+ in different fluoride matrix materials is different, which will cause differences in luminescent performance. Therefore, through the exploration of elements in A, C, D, B and X positions, it is found that in the above embodiments, the high-entropy fluoride red luminescent material shows better luminescent efficiency.

[0072] In some possible implementations, C3X 1-y F6:yMn 4+ , wherein A position is K, and X position includes Al, Ga, Sc and In four elements. In some embodiments, the molar fraction of each metal element is 0.25. The luminescent intensity of Mn 4+ ion with different doping concentrations in the high-entropy fluoride matrix activator is determined, and further preferably y is 0.03 to determine the optimal luminescent intensity.

[0073] In some possible implementations, A2X 1-y F6:yMn 4+ , wherein A position is K, and X position includes Si, Ge, Nb and Ga four elements. In some embodiments, the molar ratio of each element is 0.30:0.30:0.20:0.20. The luminescent intensity of Mn 4+ ion with different doping concentrations in the high-entropy fluoride matrix is compared, and further preferably y is 0.07 to determine the optimal luminescent intensity.

[0074] In some possible implementations, A2X 1-y F6:yMn 4+ , wherein A position is K, and X position includes Si, Ti, Ge, Nb and Al five elements. In some embodiments, the molar ratio of each element is 0.20:0.20:0.20:0.20:0.20. The luminescent intensity of Mn 4+ ion with different doping concentrations in the high-entropy fluoride matrix is compared, and further preferably y is 0.05 to determine the optimal luminescent intensity.

[0075] In some possible implementations, A2X 1-y F6:yMn 4+ , wherein A position is Cs, and X position includes Si, Ti, Ge and Zr four elements. In some embodiments, the molar ratio of each element is 0.25:0.25:0.25:0.25. The luminescent intensity of Mn 4+ ion with different doping concentrations in the high-entropy fluoride matrix is compared, and further preferably y is 0.10 to determine the optimal luminescent intensity.

[0076] In some possible implementations, A2X 1-y F6:yMn 4+ In some embodiments, the molar ratio of each element is 0.35:0.20:0.35:0.05:0.05, and the optimal luminescent intensity of the high-entropy fluoride matrix is determined by comparing the luminescent intensity at different Mn 4+ ion doping concentrations, and further preferably y is 0.10.

[0077] In some possible implementations, BX 1-y F6:yMn 4+ In some embodiments, the molar ratio of each element is 0.30:0.20:0.30:0.10:0.10, and the optimal luminescent intensity of the high-entropy fluoride matrix is determined by comparing the luminescent intensity at different Mn 4+ ion doping concentrations, and further preferably y is 0.03.

[0078] In some possible implementations, D2X 1-y F7:yMn 4+ In some embodiments, the molar ratio of each element is 0.15:0.35:0.35:0.15, and the optimal luminescent intensity of the K-based high-entropy fluoride matrix K2XF7 is determined by comparing the luminescent intensity at different Mn 4+ ion doping concentrations, and further preferably y is 0.04.

[0079] In some possible implementations, D2X 1-y F7:yMn 4+ In some embodiments, the molar ratio of each element is 0.10:0.10:0.35:0.35:0.05:0.05, and the optimal luminescent intensity of the K-based high-entropy fluoride matrix K2XF7 is determined by comparing the luminescent intensity at different Mn 4+ ion doping concentrations, and further preferably y is 0.03.

[0080] In some possible implementations, the red luminescent material includes K3(Al 0.25 ,Ga 0.25 ,In 0.25 ,Sc 0.25 ) 0.97 F6:0.03Mn 4+ , K3(Al 0.30 ,Ga0.30 In 0.15 Sc 0.15 Zn 0.05 Si 0.05 ) 0.97 F6: 0.03Mn 4+ , K2(Si 0.25 , Ge 0.25 Nb 0.25 Ga 0.25 ) 0.93 F6: 0.07Mn 4+ , K2(Si 0.20 , Ge 0.20 Ti 0.20 Nb 0.20 Al 0.20 ) 0.95 F6: 0.05Mn 4+ , Cs2(Si 0.25 , Ge 0.25 Ti 0.25 Zr 0.25 ) 0.90 F6: 0.10Mn 4+ , Cs2(Si 0.35 , Ge 0.35 Ti 0.20 Ta 0.05 Al 0.05 ) 0.90 F6: 0.10Mn 4+ , Ba(Si 0.30 , Ge 0.30 Ti 0.20 Sn 0.10 Hf 0.10 ) 0.97 F6: 0.03Mn 4+ , K2(Si 0.15 Nb 0.35 Ta 0.35 W 0.15 ) 0.96 F7: 0.04Mn 4+ , K2(Si 0.10 , Ge 0.10 Nb 0.35 Ta 0.35 W 0.05 Mo 0.05 ) 0.97 F7: 0.03Mn 4+ .

[0081] In the above embodiments of the present application, by adjusting the A-site, B-site, C-site or D-site, X-site, and Mn 4+The doping concentration component design makes the radii of each main element ion as close as possible, the electronegativity of elements similar, the charge of the lattice site balanced, and the crystal structure of each element corresponding to the matrix similar. The designed high-entropy fluoride matrix has high disorder and large lattice distortion, which can provide a low-symmetry lattice environment for Mn 4+ , enhance the radiation transition, and significantly improve the luminescent efficiency and optical performance of each luminescent material.

[0082] In a second aspect, the embodiments of the present application provide a Mn 4+ activated high-entropy fluoride red luminescent material, as shown in the accompanying drawings, comprising the following steps: Figure 1

[0083] S10. The raw material components are obtained according to the stoichiometric ratio of each metal element in the chemical formula of the Mn 4+ activated high-entropy fluoride red luminescent material.

[0084] S20. After mixing the raw material components with HF, hydrothermal reaction is performed, and after cooling, manganese source and precipitant are added for mixing treatment and solvothermal reaction in sequence to obtain the Mn 4+ activated high-entropy fluoride red luminescent material.

[0085] The embodiments of the present application provide a Mn 4+ activated high-entropy fluoride red luminescent material, and the preparation method thereof. 4+ activated high-entropy fluoride red luminescent material, and the preparation method thereof. 4+ activated high-entropy fluoride red luminescent material, and the preparation method thereof. 4+ activated high-entropy fluoride red luminescent material. The preparation process is simple and easy to operate, and is suitable for industrial large-scale production and application. The prepared high-entropy fluoride red luminescent material has high disorder and large lattice distortion through component design, which provides a low-symmetry lattice environment for Mn 4+ , enhances the radiation transition, and significantly improves the luminescent efficiency and optical performance of each luminescent material.

[0086] In the above step S10, the Mn 4+ activated high-entropy fluoride red luminescent material has a chemical formula of A2X 1-y F6:yMn 4+ , BX 1-y F6:yMn 4+ , C3X 1-y F6:yMn 4+ , D2X 1-y F7:yMn 4+ ​At least one luminescent material, wherein the A-site, C-site, and D-site are each independently selected from NH4. + Li + Na + K + 、Rb + Cs + (CH3)4N + At least one of the following; the B site is selected from Ba and / or Zn; in each luminescent material, the X site is independently selected from at least four metal elements selected from Mg, Zn, Al, Ga, Sc, In, Si, Ti, Ge, Sn, Zr, Hf, Nb, Ta, Sb, W, Mo, and Te, and the molar ratio of each metal element is in the range of 5% to 35%, and in each luminescent material, y independently satisfies 0 < y < 0.5.

[0087] In some embodiments, y independently satisfies 0.01 ≤ y ≤ 0.30 in each luminescent material. In some embodiments, the A-site, C-site, and D-site are each independently selected from K. + Or Cs + In some embodiments, the B site is selected from Ba. In some embodiments, the X site in each luminescent material includes four, five, or six metal elements, and the metal elements are in equimolar ratio or in a molar ratio ranging from 5% to 35%.

[0088] In some possible implementations, the raw material components include at least one of oxides, fluorides, and metal salts. Metal salts include nitrates, phosphates, and chlorides.

[0089] In some possible implementations, the purity of the raw material components is not less than 99%; high purity avoids the introduction of impurities and ensures product purity.

[0090] In some embodiments, according to the above-described Mn 4+ The raw material components are obtained by determining the stoichiometric ratio of each metal element at position X in the chemical formula of the activated high-entropy fluoride red luminescent material. The stoichiometric ratio can be the actual ratio of each element.

[0091] In step S20 above, the raw material components are mixed with HF and then subjected to a hydrothermal reaction.

[0092] In some embodiments, the concentration of HF is 10% to 49%. Exemplarily, the concentration of HF can be any typical but non-limiting point value or a range between any two point values, such as 10%, 20%, 30%, 40%, 49%.

[0093] In some embodiments, the ratio of the amount of HF added to the raw material components is (1-10) mL:1 g, which ensures the hydrothermal reaction of the raw material components. For example, the ratio of the amount of HF added to the raw material components can be 1 mL:1 g, 2 mL:1 g, 3 mL:1 g, 4 mL:1 g, 5 mL:1 g, 6 mL:1 g, 7 mL:1 g, 8 mL:1 g, 9 mL:1 g, 10 mL:1 g, or any interval value between any two of the above typical but non-limiting point values.

[0094] In some possible implementations, the conditions of the hydrothermal reaction include: reacting in a high-pressure reactor at a temperature of 100-200℃ for 1-8 h. Under these conditions, the hydrothermal reaction of HF on the raw material components is facilitated, and a fluoride-based high-entropy fluoride is prepared. For example, the reaction temperature can be 100℃, 120℃, 140℃, 150℃, 160℃, 180℃, 200℃, or any interval value between any two of the above typical but non-limiting point values, and the reaction time can be 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, or any interval value between any two of the above typical but non-limiting point values.

[0095] In some possible implementations, the manganese source includes K2MnF6; the manganese source is subjected to a solvothermal reaction to obtain Mn 4+ doped into the fluoride-based matrix material to obtain Mn 4+ activates the high-entropy fluoride red luminescent material.

[0096] The precipitant used in the embodiments of the present application can be a fluoride, a hydrofluoride, or a corresponding metal salt corresponding to the A, B, C, and D site elements. In some possible implementations, for K2X 1-y F6:yMn 4+ The precipitant includes at least one of KHF2, KF, K2CO3, and KNO3.

[0097] In some possible implementations, the mixing step includes: after adding the manganese source for dissolution, adding the HF solution of the precipitant dropwise, and stirring at room temperature for 10-30 min. The manganese source can be fully dissolved by stirring for 2-30 min (which can be 2 min, 5 min, 10 min, 20 min, 30 min, etc.) after the manganese source is added. In addition, the precipitant is dissolved in HF in advance to form a solution, which is added by dropwise addition, which facilitates the uniform precipitation of the product. The stirring time at room temperature can be 10 min, 15 min, 20 min, 25 min, 30 min, etc.

[0098] In some possible implementation manners, the conditions of the solvothermal reaction include: reacting for 1h-5h in a high-pressure reaction kettle at a temperature of 50-100℃; under the reaction conditions, the manganese ions can be doped into the high-entropy fluoride matrix. Exemplarily, the reaction temperature can be 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, or any point value or interval value between any two point values of the typical but non-limiting values, and the reaction time can be 1h, 2h, 3h, 4h, 5h, or any point value or interval value between any two point values of the typical but non-limiting values.

[0099] In some possible implementation manners, after the solvothermal reaction, the reaction product is collected after being separated and cooled to room temperature, and then dried at a temperature of 50-85℃ for 4h-12h after being washed. The by-products are removed by separation and washing, the product is purified, and the solvent is removed by drying to obtain Mn 4+ The high-entropy fluoride red luminescent material is activated.

[0100] In a third aspect, the embodiments of the present application provide a light-emitting diode (LED), which contains the Mn 4+ The high-entropy fluoride red luminescent material or the Mn 4+ The high-entropy fluoride red luminescent material is activated.

[0101] In the light-emitting diode of the embodiments of the present application, the Mn 4+ The high-entropy fluoride red luminescent material is activated, and the light-emitting diode has high luminous efficiency, high color rendering index, and low correlated color temperature.

[0102] In some possible implementation manners, the light-emitting diode contains red luminescent material and yellow luminescent material in a mass ratio of 2:1. In this case, the high-entropy fluoride red luminescent material is combined with commercial yellow luminescent material to prepare a high-luminous-efficiency, high-color-rendering-index, and low-correlated-color-temperature warm white LED device.

[0103] In some possible implementation manners, the light-emitting diode contains red luminescent material and green luminescent material in a mass ratio of 1:1. In this case, the high-entropy fluoride red luminescent material is combined with commercial green luminescent material to prepare a high-quality wide color gamut backlight device.

[0104] In some possible implementation manners, the light-emitting diode is excited by a blue light chip.

[0105] For the above-mentioned implementation details and operations of the present application to be clearly understood by those skilled in the art, and the further performance of the Mn4+ activated high-entropy fluoride red luminescent material and its preparation method embodiment, the following is illustrated by multiple examples to illustrate the above technical solutions.

[0106] Example 1

[0107] A Mn 4+ activated high-entropy fluoride red luminescent material, which comprises a compound composition formula K3(Al 0.25 ,Ga 0.25 ,In 0.25 ,Sc 0.25 ) 0.97 F6:0.03Mn 4+ .

[0108] The preparation steps include: according to the actual ratio of chemical elements in the luminescent material, accurately weighing the corresponding raw materials, first adding nitrate Al(NO3)3·9H2O and oxide Ga2O3, In2O3 and Sc2O3 raw materials into the reaction container in turn, then adding 4mL HF, mechanical stirring for 15min, then transferring the container to the autoclave and placing it into the reaction equipment, and incubating at 180℃ for 5h. After the reaction is completed, cool to room temperature, then add manganese source K2MnF6 to the transparent solution, stir for 2min. Dissolve KHF2 in 3mL HF, add it dropwise to the above solution, and continue to stir at room temperature for 15min, then place the container in the autoclave and transfer it to the reaction equipment, and incubate at 80℃ for 2.5h. After the reaction is completed and cooled to room temperature, collect the yellow product, wash it with 20mL acetic acid and anhydrous ethanol for 2 times respectively, and finally place it in a 65℃ drying box for drying for 6h, and finally obtain the high-entropy fluoride red luminescent material.

[0109] Example 2

[0110] A Mn 4+ activated high-entropy fluoride red luminescent material, which comprises a compound composition formula K3(Al 0.30 ,Ga 0.30 ,In 0.15 ,Sc 0.15 ,Zn 0.05 ,Si 0.05 ) 0.97 F6:0.03Mn 4+ .

[0111] The preparation steps include: according to the actual proportion of chemical elements in the luminescent material, accurately weighing the corresponding raw materials, first adding nitrate Al (NO3) 3·9H2O and oxide Ga2O3, In2O3, Sc2O3, ZnO2 and SiO2 raw materials into the reaction container in turn, then adding 5 mL HF, mechanical stirring for 20 min, then transferring the container to the autoclave and placing it in the reaction equipment, and keeping it at 200 ℃ for 3 h. After the reaction is completed, cool to room temperature, then add manganese source K2MnF6 to the transparent solution, stir for 2 min. Then dissolve KF in 2 mL HF, add it to the above solution dropwise, and continue to stir at room temperature for 25 min, then place the liner in the autoclave and transfer it to the drying box, and keep it at 85 ℃ for 2 h. After the reaction is completed and cooled to room temperature, collect the yellow product, wash it with 25 mL acetic acid and anhydrous ethanol for 2 times respectively, and finally place it in a 65 ℃ drying box for drying for 6 h, and finally obtain the high-entropy fluoride red luminescent material.

[0112] Example 3

[0113] A Mn 4+ activated high-entropy fluoride red luminescent material, which comprises a compound composition formula K2(Si 0.25 ,Ge 0.25 ,Nb 0.25 ,Ga 0.25 ) 0.93 F6:0.07Mn 4+ .

[0114] The preparation steps include: according to the actual proportion of chemical elements in the luminescent material, accurately weighing the corresponding raw materials, first adding oxide SiO2, GeO2, Nb2O5 and Ga2O3 raw materials into the reaction container in turn, then adding 6 mL HF, magnetic stirring for 30 min, then transferring the container to the autoclave and placing it in the reaction equipment, and keeping it at 200 ℃ for 1 h. After the reaction is completed, cool to room temperature, then add manganese source K2MnF6 to the transparent solution, stir for 2 min. Then dissolve KHF2 in 2 mL HF, add it to the above solution dropwise, and continue to stir at room temperature for 10 min, then place the liner in the autoclave and transfer it to the reaction equipment, and keep it at 100 ℃ for 2 h. After the reaction is completed and cooled to room temperature, collect the yellow product, wash it with 20 mL acetic acid and anhydrous ethanol for 3 times respectively, and finally place it in a 70 ℃ drying box for drying for 5 h, and finally obtain the high-entropy fluoride red luminescent material.

[0115] Examples 4-8

[0116] Examples 4-8 respectively provide a Mn 4+ activated high-entropy fluoride red luminescent material, which is different from example 3 in that the doping concentration of Mn 4+ is different, and other preparation and characterization methods remain the same as example 3.

[0117] In Example 4, Mn 4+ The doping concentration was 0.01, and the resulting Mn 4+ Activating high-entropy fluoride red luminescent materials yields materials with the chemical formula K2(Si). 0.25 ,Ge 0.25 ,Nb 0.25 Ga 0.25 ) 0.99 F6:0.01Mn 4+ .

[0118] In Example 5, Mn 4+ The doping concentration was 0.03, and the resulting Mn 4+ Activating high-entropy fluoride red luminescent materials yields materials with the chemical formula K2(Si). 0.25 ,Ge 0.25 ,Nb 0.25 Ga 0.25 ) 0.97 F6:0.03Mn 4+ .

[0119] In Example 6, Mn 4+ The doping concentration was 0.05, and the resulting Mn 4+ Activating high-entropy fluoride red luminescent materials yields materials with the chemical formula K2(Si). 0.25 ,Ge 0.25 ,Nb 0.25 Ga 0.25 ) 0.95 F6:0.05Mn 4+ .

[0120] In Example 7, Mn 4+ The doping concentration was 0.09, and the resulting Mn 4+ Activating high-entropy fluoride red luminescent materials yields materials with the chemical formula K2(Si). 0.25 ,Ge 0.25 ,Nb 0.25 Ga 0.25 ) 0.91 F6:0.09Mn 4+ .

[0121] In Example 8, Mn 4+ The doping concentration was 0.11, and the resulting Mn 4+ Activating high-entropy fluoride red luminescent materials yields materials with the chemical formula K2(Si). 0.25 ,Ge 0.25 ,Nb 0.25 Ga 0.25 ) 0.89 F6:0.11Mn 4+ .

[0122] Example 9

[0123] A Mn 4+ High-entropy fluoride red luminescent material activated by K2(Si 0.20 ,Ge 0.20 ,Ti 0.20 ,Nb 0.20 ,Al 0.20 ) 0.95 F6:0.05Mn 4+ .

[0124] The preparation steps include: according to the actual proportion of chemical elements in the luminescent material, accurately weighing the corresponding raw materials, first adding oxide SiO2, GeO2, TiO2, Nb2O5 and hydroxide Al(OH)3 raw materials into the reaction container in turn, then adding 6 mL of HF, mechanically stirring for 25 min, then transferring the container to an autoclave and placing it in a reaction device, and incubating at 200℃ for 2 h. After the reaction is completed, cool to room temperature, then add manganese source K2MnF6 to the transparent solution and stir for 4 min. Dissolve KHF2 in 2 mL of HF, add it dropwise to the above solution, and continue to stir at room temperature for 15 min, then place the inner liner in an autoclave and transfer it to a reaction device, and incubate at 90℃ for 1.5 h. After the reaction is completed and cooled to room temperature, collect the yellow product, wash it with 20 mL of acetic acid and anhydrous ethanol for 3 times, and finally place it in a 65℃ drying oven for drying for 5 h, and finally obtain a high-entropy fluoride red luminescent material.

[0125] Example 10

[0126] A Mn 4+ High-entropy fluoride red luminescent material activated by Cs2(Si 0.25 ,Ge 0.25 ,Ti 0.25 ,Zr 0.25 ) 0.90 F6:0.10Mn 4+ .

[0127] The preparation steps include: according to the actual proportion of chemical elements in the luminescent material, accurately weighing the corresponding raw materials, first adding oxide SiO2, GeO2, TiO2, ZrO2raw materials into the reaction container in turn, then adding 5mL HF, mechanical stirring for 20min, then transferring the container to the autoclave and placing it into the reaction equipment, and keeping it at 170℃ for 5h. After the reaction is completed, cool to room temperature, then add manganese source K2MnF6to the solution, stir for 5min. Then add CsF directly into the above solution, and continue to stir at room temperature for 30min, then place the container into the autoclave and transfer it to the reaction equipment, and keep it at 100℃ for 2h. After the reaction is completed and cooled to room temperature, collect the yellow product, wash it with 20mL acetic acid and anhydrous ethanol for 3 times respectively, and finally dry it in a 70℃ drying box for 4h, and finally obtain the high-entropy fluoride red luminescent material.

[0128] Example 11

[0129] A Mn 4+ activated high-entropy fluoride red luminescent material, which comprises a compound composition formula of Cs2(Si 0.35 ,Ge 0.35 ,Ti 0.20 ,Ta 0.05 ,Al 0.05 ) 0.90 F6:0.10Mn 4+ .

[0130] The preparation steps include: according to the actual proportion of chemical elements in the luminescent material, accurately weighing the corresponding raw materials, first adding oxide SiO2, GeO2, TiO2, Nb2O5and hydroxide Al(OH)3raw materials into the reaction container in turn, then adding 6mL HF, mechanical stirring for 25min, then transferring the container to the autoclave and placing it into the reaction equipment, and keeping it at 200℃ for 4h. After the reaction is completed, cool to room temperature, then add manganese source K2MnF6to the solution, stir for 3min. Then add CsF directly into the above solution, and continue to stir at room temperature for 20min, then place the container into the autoclave and transfer it to the reaction equipment, and keep it at 95℃ for 1.5h. After the reaction is completed and cooled to room temperature, collect the yellow product, wash it with 30mL acetic acid and anhydrous ethanol for 3 times respectively, and finally dry it in a 70℃ drying box for 5h, and finally obtain the high-entropy fluoride red luminescent material.

[0131] Example 12

[0132] A Mn 4+ activated high-entropy fluoride red luminescent material, which comprises a compound composition formula of Ba(Si 0.30 ,Ge 0.30 ,Ti 0.20 ,Sn 0.10 ,Hf0.10 ) 0.97 F6: 0.03 Mn 4+ .

[0133] The preparation steps include: according to the actual proportion of chemical elements in the luminescent material, accurately weighing the corresponding raw materials, first adding oxide SiO2, GeO2, TiO2, HfO2 and elemental Sn raw materials into the reaction container in turn, then adding 5 mL HF, mechanically stirring for 20 min, then transferring the container to the autoclave and placing it in the reaction equipment, and incubating at 160℃ for 10 h. After the reaction is completed, cool to room temperature, then add manganese source K2MnF6 to the solution, stir for 5 min. Then add BaF directly to the above solution, and continue to stir at room temperature for 20 min, then place the container in the autoclave and transfer it to the reaction equipment, and incubate at 75℃ for 3 h. After the reaction is completed and cooled to room temperature, collect the product, wash it with 20 mL of acetic acid and anhydrous ethanol for 2 times respectively, and finally dry it in a 60℃ drying box for 8 h, and finally obtain a high-entropy fluoride red luminescent material.

[0134] Example 13

[0135] A Mn 4+ activated high-entropy fluoride red luminescent material, which comprises a compound composition formula K2(Si 0.15 , Nb 0.35 , Ta 0.35 , W 0.15 ) 0.96 F7: 0.04 Mn 4+ .

[0136] The preparation steps include: according to the actual proportion of chemical elements in the luminescent material, accurately weighing the corresponding raw materials, first adding oxide SiO2, Nb2O5, Ta2O5 and tungstate K2WO4 raw materials into the reaction container in turn, then adding 5 mL HF, mechanically stirring for 15 min, then transferring the container to the autoclave and placing it in the reaction equipment, and incubating at 150℃ for 9 h. After the reaction is completed, cool to room temperature, then add manganese source K2MnF6 to the solution, stir for 3 min. Then add KF directly to the above solution, and continue to stir at room temperature for 25 min, then place the container in the autoclave and transfer it to the drying box, and incubate at 90℃ for 2.5 h. After the reaction is completed and cooled to room temperature, collect the product, wash it with 25 mL of acetic acid and anhydrous ethanol for 3 times respectively, and finally dry it in a 65℃ drying box for 6 h, and finally obtain a high-entropy fluoride red luminescent material.

[0137] Example 14

[0138] A Mn 4+ activated high-entropy fluoride red luminescent material, which comprises a compound composition formula K2(Si 0.10 , Ge0.10 Nb 0.35 Ta 0.35 W 0.05 Mo 0.05 ) 0.97 F7:0.03Mn 4+ .

[0139] The preparation steps include: according to the actual proportion of chemical elements in the luminescent material, accurately weighing the corresponding raw materials, first adding oxide SiO2, GeO2, Nb2O5, Ta2O5, MoO3 and tungstate K2WO4 raw materials into the reaction container in turn, then adding 8 mL HF, mechanical stirring for 20 min, then transferring the container to the autoclave and placing it in the reaction equipment, and incubating at 160℃ for 6 h. After the reaction is completed, cool to room temperature, then add manganese source K2MnF6 to the solution, stir for 5 min. Then KF is directly added to the above solution, and continue to stir at room temperature for 35 min, then place the container in the autoclave and transfer it to the reaction equipment, and incubate at 80℃ for 2.5 h. After the reaction is completed and cooled to room temperature, collect the product, wash it with 25 mL of acetic acid and anhydrous ethanol for 3 times, and finally dry it in a 70℃ drying oven for 5 h, to obtain a high-entropy fluoride red luminescent material.

[0140] Comparative Example 1

[0141] A red luminescent material comprising a compound with a composition formula of K3Al 0.97 F6:0.03Mn 4+ .

[0142] The preparation steps include: according to the actual proportion of chemical elements in the luminescent material, accurately weighing the corresponding raw materials, first adding Al(NO3)3·9H2O into the reaction container, then adding 4 mL HF, stirring for 5 min, then transferring the reaction container to the autoclave and placing it in the reaction equipment, and incubating at 80℃ for 4 h. After the reaction is completed, cool to room temperature, then add manganese source K2MnF6 to the transparent solution, stir for 2 min. Then dissolve KHF2 in 3 mL HF, add it dropwise to the above solution, and continue to stir at room temperature for 15 min, then place the lining in the autoclave and transfer it to the constant temperature air drying oven, and incubate at 80℃ for 2.5 h. After the reaction is completed and cooled to room temperature, collect the yellow product, wash it with 25 mL of acetic acid and anhydrous ethanol for 2 times, and finally dry it in a 65℃ drying oven for 6 h, to obtain a red luminescent material.

[0143] Comparative Example 2

[0144] A red luminescent material comprising a compound with a composition formula of K2Si 0.93 F6:0.07Mn 4+ .

[0145] The preparation steps include: according to the actual proportion of chemical elements in the luminescent material, accurately weighing the corresponding raw materials, first adding SiO2 in the reaction container, then adding 5 mL HF, stirring for 10 min, then transferring the liner to the autoclave and placing it in the reaction equipment, and incubating at 100°C for 2 h. After the reaction is completed, cool to room temperature, then add manganese source K2MnF6 to the transparent solution, stir for 3 min. Then dissolve KHF2 in 2 mL HF, add it dropwise to the above solution, and continue to stir at room temperature for 20 min, then place the liner in the autoclave and transfer it to the reaction equipment, incubate at 90°C for 2 h. After the reaction is completed and cooled to room temperature, collect the yellow product, wash it with 20 mL of acetic acid and anhydrous ethanol for 3 times, and finally place it in a 70°C drying oven for 5 h, and finally obtain a red luminescent material.

[0146] Comparative Example 3

[0147] A red luminescent material comprising a compound with a composition formula of Cs2Si 0.90 F6:0.10Mn 4+ .

[0148] The preparation steps include: according to the actual proportion of chemical elements in the luminescent material, accurately weighing the corresponding raw materials, first adding SiO2 in the reaction container, then adding 5 mL HF, stirring for 10 min, then transferring the liner to the autoclave and placing it in the reaction equipment, and incubating at 100°C for 2 h. After the reaction is completed, cool to room temperature, then add manganese source K2MnF6 to the transparent solution, stir for 3 min. Then dissolve KHF2 in 2 mL HF, add it dropwise to the above solution, and continue to stir at room temperature for 20 min, then place the liner in the autoclave and transfer it to the reaction equipment, incubate at 90°C for 2 h. After the reaction is completed and cooled to room temperature, collect the yellow product, wash it with 20 mL of acetic acid and anhydrous ethanol for 3 times, and finally place it in a 70°C drying oven for 5 h, and finally obtain a red luminescent material.

[0149] Comparative Example 4

[0150] A red luminescent material comprising a compound with a composition formula of K2Nb 0.96 F7:0.04Mn 4+ .

[0151] The preparation steps include: accurately weighing the corresponding raw materials according to the actual ratio of chemical elements in the luminescent material; first, adding Nb₂O₅ raw material to the reaction vessel, followed by adding 5 mL of HF, stirring for 25 min; then transferring the liner to an autoclave and placing it in the reaction equipment, maintaining the temperature at 200℃ for 2 h. After the reaction is complete and the liner cools to room temperature, adding manganese source K₂MnF₆ to the transparent solution, stirring for 2 min; then dissolving KHF₂ in 3 mL of HF and adding it dropwise to the above solution, continuing to stir at room temperature for 25 min; then placing the vessel in an autoclave and transferring it to a drying oven, maintaining the temperature at 100℃ for 1.5 h. After the reaction is complete and cooled to room temperature, collecting the yellow product, washing it three times with 30 mL of acetic acid and anhydrous ethanol respectively, and finally drying it in a drying oven at 60℃ for 8 h to finally obtain the red luminescent material.

[0152] Furthermore, to verify the progressiveness of the embodiments of this application, the following performance tests were performed on the above embodiments and comparative examples:

[0153] 1. The quantum efficiency of the red luminescent materials prepared in the above embodiments and comparative examples was tested respectively:

[0154] The quantum efficiency of all embodiments in this application was measured using a Hitachi F-7000 fluorescence spectrometer equipped with an integrating sphere, the inner surface of which was uniformly coated with barium sulfate. During testing, a 450W xenon lamp was used as the light source, with both excitation and emission slits at 5.0 nm, a scan step size of 1 nm, and the excitation wavelength being the optimal excitation wavelength for the sample. The spectral acquisition range was 450–700 nm. Spectra of a blank control sample (coated with barium sulfate) and a red phosphor sample were acquired, as exemplarily shown in the attached figure. Figure 2 As shown, the black line represents the excitation spectrum of the blank control sample, the red line represents the excitation spectrum of the red phosphor sample, and the blue line represents the emission spectrum of the red phosphor sample. The final internal quantum efficiency (IQE), absorption efficiency (AE), and external quantum efficiency (EQE) of the samples were determined using the following formulas:

[0155]

[0156] EQE=AE×IQE, formula III;

[0157] Among them, L S E represents the emission spectrum of a red phosphor sample. S E represents the excitation spectrum of a sample containing red phosphor within the integrating sphere. R This represents the excitation spectrum of the integrating sphere with only BaSO4 as a reference.

[0158] The quantum efficiency tests for each embodiment and comparative example are shown in Table 1 below:

[0159] Table 1

[0160]

[0161] As can be seen from the test results in Table 1 above, the Mn prepared in the embodiments of this application... 4+ Activation of high-entropy fluoride red luminescent materials all exhibited better quantum luminescence efficiency. This indicates that the high-entropy fluoride red luminescent material matrix designed in this application has better high disorder and lattice distortion, and can be used for Mn. 4+ Providing a lattice environment with lower symmetry helps to enhance radiative transitions and better improve the luminescence efficiency of high-entropy fluoride red luminescent materials.

[0162] 2. Regarding the Mn prepared in Example 3 4+ Tests were conducted on the morphology and elemental distribution of the activated high-entropy fluoride red luminescent material, as shown in the attached figure. Figure 3 As shown, the crystal structure is complete, the elements are evenly distributed, and the sample has high compositional homogeneity, confirming the successful formation of single-phase high-entropy fluorides.

[0163] 3. Mn prepared in Example 2 4+ Emission spectrum of activated high-entropy fluoride red luminescent material (attached) Figure 4 As shown, after high-entropy design, the emission spectrum of the prepared high-entropy fluoride red phosphor begins to show a significant zero-phonon line peak (ZPL) and fluorescence enhancement at 622 nm, indicating that [MnF6] 2- The distortion of the octahedron reduces the symmetry of its local structure, which helps to improve the luminescence efficiency and performance of fluoride red phosphors.

[0164] 4. The Mn prepared in Example 3 4+ Activation of high-entropy fluoride red luminescent materials (K2(Si) 0.25 ,Ge 0.25 ,Nb 0.25 Ga 0.25 ) 0.93 F6:0.07Mn 4+ The red luminescent material (K2Si) prepared in Comparative Example 2 was compared with that prepared in Comparative Example 2 0.93 F6:0.07Mn 4+ Raman spectroscopy was performed separately, and the Raman spectra are attached. Figure 5 As shown, compared to the single matrix in Comparative Example 2, the Raman bands of the high-entropy fluoride red luminescent material in Example 3 of this application are wider than those of the single matrix because the coexistence of multiple types of cations at the X-position in a chemically disordered state leads to lattice anharmonicity. Furthermore, these broadened Raman modes provide direct evidence that the high-entropy fluoride red luminescent material of this application exhibits severe lattice distortion, with the luminescent unit [MnF6] showing a significant lattice distortion. 2- The local structural symmetry of octahedrons is reduced compared to that of a single matrix.

[0165] 5、Mn 4+ The activated high-entropy fluoride red luminescent material was tested by X-ray diffraction, and the XRD diffraction graph is shown in the following figure. Figure 6 As shown, the different Mn 4+ The high-entropy fluoride red luminescent material with different doping concentrations is consistent with the corresponding standard card, indicating that it is a pure phase, and a single-phase high-entropy fluoride is successfully synthesized.

[0166] 6、Mn 4+ The emission spectrum of the activated high-entropy fluoride red luminescent material is shown in the following figure. Figure 7 As shown, the different Mn 4+ The high-entropy fluoride red luminescent material with different doping concentrations all shows a typical narrow-band red light emission peak, which meets the general expectation of fluoride red fluorescent powder.

[0167] 7、Mn 4+ The excitation and emission spectrum of the activated high-entropy fluoride red luminescent material is shown in the following figure. Figure 8 As shown, the prepared sample has a unique narrow-band red light emission and a wide-band blue light excitation characteristic, which meets the general expectation of fluoride red fluorescent powder.

[0168] 8、Mn 4+ The excitation and emission spectrum of the activated high-entropy fluoride red luminescent material is shown in the following figure. Figure 9 As shown, the prepared sample has a unique narrow-band red light emission and a wide-band blue light excitation characteristic, which meets the general expectation of fluoride red fluorescent powder.

[0169] 9、Mn 4+ The activated high-entropy fluoride red luminescent material and the commercial yellow fluorescent powder YAG:Ce 3 + The two are combined and packaged into a white light LED device at a mass ratio of 2:1, and the electroluminescence spectrum of the device is shown in the following figure. Figure 10 The CRI (color rendering index) of the device is 95.3, the CCT (correlated color temperature) is 3753K, and the LE (luminous flux) is 154.46 lm / w. As shown, the prepared high-entropy fluoride red fluorescent powder can be used to prepare a warm white light LED device with high luminous efficiency, high color rendering index, and low correlated color temperature, which is an excellent red light material for ideal white light LED.

[0170] 10、Mn 4+ The activated high-entropy fluoride red luminescent material and the commercial green fluorescent powder β-Sialon:Eu 2+The white LED device was packaged by combining the phosphors in a mass ratio of 1:1, and the electroluminescence spectrum of the device is shown in FIG. 8. Figure 11 As shown in FIG. 8, the comparison results of the color gamut of the display device with the NTSC color gamut and the Rec.2020 color gamut are 1931 Gamut (NTSC%) = 122.2%, and 1931 Gamut (Rec.2020%) = 91.3%. It can be seen that the prepared high-entropy fluoride red phosphor can be used to prepare a high-quality wide color gamut backlight device.

[0171] The preferred embodiments of the present application have been described above with the aid of drawings, but the present application is not limited to these preferred embodiments, and any modifications, equivalent replacements, and improvements made within the spirit and principle of the present application shall fall within the protection scope of the present application.

Claims

1. A Mn 4+ high-entropy fluoride red-emitting material activated by, at least one luminescent material selected from the group consisting of A2X 1-y F6:yMn 4+ , BX 1-y F6:yMn 4+ , C3X 1-y F6:yMn 4+ , D2X 1-y F7: yMn 4+ , wherein A, C and D are independently selected from K + or Cs + ; B is selected from Ba and / or Zn; X in each of the luminescent materials independently comprises four, five or six metal elements selected from Mg, Zn, Al, Ga, Sc, In, Si, Ti, Ge, Sn, Zr, Hf, Nb, Ta, Sb, W, Mo and Te, the ion radii of the metal elements in X are close to each other, the electronegativities of the metal elements in X are similar, the charges of the lattice sites are balanced, the crystal structures of the metal elements in X are similar to the matrix, and the molar ratio of each metal element is in the range of 5% to 35%; and y in each of the luminescent materials independently satisfies 0.01≤y≤0.

30.

2. The Mn of claim 1 4+ activating high-entropy fluoride red luminescent material, characterized by, The metal elements in the X position of each of the luminescent materials are in equimolar ratio.

3. The Mn of claim 2 4+ activating high-entropy fluoride red luminescent material, characterized by, The C3X 1-y F6: yMn 4+ In which the C position is K, and the X position includes four elements of Al, Ga, Sc, and In. Alternatively, the A2X 1-y F6: yMn 4+ In this case, the A site is K, and the X site includes four elements of Si, Ge, Nb, and Ga. Alternatively, the A2X 1-y F6: yMn 4+ In this case, the A site is K, and the X site includes five elements of Si, Ti, Ge, Nb, and Al. Alternatively, the A2X 1-y F6: yMn 4+ In this case, A is Cs, and X includes Si, Ti, Ge, and Zr. Alternatively, the A2X 1-y F6: yMn 4+ In this case, A is Cs, and X includes five elements of Si, Ti, Ge, Ta, and Al. Alternatively, the BX 1-y F6: yMn 4+ In this case, the B site is Ba and the X site includes five elements of Si, Ti, Ge, Sn, and Hf. Or, the D2X 1-y F7: yMn 4+ In the formula, the D position is K, and the X position includes Si, Ta, Nb, and Mo. Alternatively, the D2X 1-y F7: yMn 4+ In this case, the D position is K, and the X position includes six elements of Si, Ge, Ta, Nb, W, and Mo.

4. The Mn of any one of claims 1-3 4+ Activating high-entropy fluoride red luminescent material, characterized in that, The red luminescent material comprises K3(Al 0.25 ,Ga 0.25 ,In 0.25 ,Sc 0.25 ) 0.97 F6:0.03Mn 4+ , K3(Al 0.30 ,Ga 0.30 ,In 0.15 ,Sc 0.15 ,Zn 0.05 ,Si 0.05 ) 0.97 F6:0.03Mn 4+ , K2(Si 0.25 ,Ge 0.25 ,Nb 0.25 ,Ga 0.25 ) 0.93 F6:0.07Mn 4+ , K2(Si 0.20 ,Ge 0.20 ,Ti 0.20 ,Nb 0.20 ,Al 0.20 ) 0.95 F6:0.05Mn 4+ , Cs2(Si 0.25 ,Ge 0.25 ,Ti 0.25 ,Zr 0.25 ) 0.90 F6:0.10Mn 4+ , Cs2(Si 0.35 ,Ge 0.35 ,Ti 0.20 ,Ta 0.05 ,Al 0.05 ) 0.90 F6:0.10Mn 4+ , Ba(Si 0.30 ,Ge 0.30 ,Ti 0.20 ,Sn 0.10 ,Hf 0.10 ) 0.97 F6:0.03Mn 4+ , K 2. (Si 0.15 ,Nb 0.35 ,Ta 0.35 ,W 0.15 ) 0.96 F7:0.04Mn 4+ , K2(Si 0.10 ,Ge 0.10 ,Nb 0.35 ,Ta 0.35 ,W 0.05 ,Mo 0.05 ) 0.97 F7:0.03Mn 4+ at least one of F7 and F8.

5. A Mn 4+ A method for preparing an activated high-entropy fluoride red luminescent material, characterized by, The method comprises the following steps: Mn according to any one of claims 1 to 4 4+ The stoichiometric ratio of each metal element in the chemical formula of the activated high-entropy fluoride red luminescent material is obtained as the raw material component; After mixing the raw material components with HF, hydrothermal reaction is carried out, and after cooling, manganese source and precipitant are added to carry out mixing treatment and solvothermal reaction in sequence to obtain Mn 4+ Activate high-entropy fluoride red luminescent material; The conditions of the hydrothermal reaction include: reacting in a high-pressure reaction kettle at a temperature of 100-200 DEG C for 1-8 hours; and the conditions of the solvothermal reaction include: reacting in a high-pressure reaction kettle at a temperature of 50-100 DEG C for 1-5 hours.

6. The Mn of claim 5 4+ A method for preparing an activated high-entropy fluoride red luminescent material, characterized by comprising the following steps: The material type of the raw material component includes at least one of an oxide, a fluoride and a metal salt; And / or, the purity of the raw material component is not less than 99%; And / or, the manganese source includes K2MnF6; and / or, the precipitant comprises the Mn 4+ activating at least one of a fluoride, a fluorohydride, a metal salt corresponding to the A-site, B-site, C-site and D-site elements in the high-entropy fluoride red luminescent material. And / or, the ratio of the amount of HF to the raw material component is (1-10) mL:1 g; And / or, the concentration of the HF is 10-49%.

7. The Mn of claim 6 4+ A method for preparing an activated high-entropy fluoride red luminescent material, characterized by comprising the following steps: The mixing process comprises: after adding the manganese source for dissolution, adding the HF solution of the precipitant dropwise, and stirring at room temperature for 10-30 minutes; And / or, the conditions of the solvothermal reaction include: reacting in a high-pressure reaction kettle at a temperature of 50-100 DEG C for 1-5 hours; And / or, the precipitant includes at least one of KHF2, KF, K2CO3 and KNO3.

8. A light emitting diode, comprising: The light emitting diode contains the Mn as claimed in any one of claims 1 to 4 4+ activating the high-entropy fluoride red luminescent material or the Mn prepared by the method as claimed in any one of claims 5 to 7 4+ activating the high-entropy fluoride red luminescent material.

9. The light-emitting diode as described in claim 8, characterized in that, In the light-emitting diode, the red luminescent material and the yellow luminescent material are included in a mass ratio of 2:1; And / or, in the light-emitting diode, the red luminescent material and the green luminescent material are included in a mass ratio of 1:1; And / or, the light-emitting diode is excited by a blue light chip.

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