KR20180110126A - A method for producing a red light emitting material excited by blue light - Google Patents

Abstract

The present invention provides a method for producing a red light emitting material excited by blue light without using hydrofluoric acid, wherein the chemical composition of the red light emitting material is A ₂ X _{1 -y} F _6: yMn ⁴⁺ , wherein A Is at least one selected from alkali metal elements; X is at least one selected from Ti, Si, Ge and Zr; y represents the molar percentage coefficient of the Mn ⁴⁺ ion relative to the X ⁴⁺ ion, 0 < y? 0.10; The method comprises the steps of mixing a substrate material containing X and a reaction solvent containing formic acid, a mixture of at least one of acetic acid and fluoroacetic acid with anhydrous ethanol or formic acid, and at least one of acetic acid and fluoroacetic acid, ; ^Adding a fluoride of Mn ⁴⁺ to a first mixed solution to obtain a second mixed solution; And a fluoride of A in a second mixed solution to obtain a precipitate to obtain a red luminescent material. This method does not affect environmental pollution.

Description

A method for producing a red light emitting material excited by blue light

The present invention relates to a method for manufacturing a red light emitting material excited by blue light, and more particularly, to a method for manufacturing a red light emitting material of Mn ⁴⁺ ion doped fluoride for a blue light semiconductor light emitting diode (LED).

The Mn ⁴⁺ -doped fluoride red light emitting material is strong in the blue light region and has a wide excitation band and a strong red light narrow band, so it can be applied to GaN base white light LED illumination. Typically, a large amount of hydrofluoric acid is used to prepare a Mn ⁴⁺ -doped fluoride red light emitting material. For example, in the patent document with the disclosure number US2006169998A1, a method for producing A ₂ MF ₆ (A is Na, K, Rb and the like and M is Ti, Si, Sn, Ge, etc.) is disclosed. The method includes the steps of dissolving various raw materials in a high concentration of hydrofluoric acid and obtaining a sample through the crystal; This method has a disadvantage that the operation time is long, the amount of hydrofluoric acid used is large, and the appearance of the product is not uniform. In addition, A ₂ MF ₆ (A is a combination of one or more of Li, Na, K, Rb and Cs; M is one or more of Ti, Si, Sn, Ge, Zr Wherein the method comprises using a potassium hexafluoro man- netate or sodium hexafluoro-man- netate as the Mn ⁴⁺ source and pre-treating it with a hydrofluoric acid solution A ₂ MF ₆ substrate material to obtain a sample. However, hydrofluoric acid is used in the production of A ₂ MF ₆ , but hydrofluoric acid is a corrosive and toxic chemical reagent. Therefore, how to reduce the use amount of hydrofluoric acid to obtain a high-efficiency fluoride red light emitting material has important research significance and application prospects.

An object of the present invention is to provide a method for producing a red light emitting material excited by blue light without using hydrofluoric acid.

There is provided a method of producing a red light emitting material excited by blue light in an exemplary embodiment of the present invention, wherein the chemical composition of the red light emitting material is A ₂ X _{1 -y} F _6: yMn ⁴⁺ , wherein A is At least one selected from alkali metal elements; X is at least one selected from Ti, Si, Ge and Zr; y represents the molar percentage coefficient of the Mn ⁴⁺ ion relative to the X ⁴⁺ ion, 0 < y? 0.10;

The method comprises the steps of mixing a substrate material containing X and a reaction solvent containing formic acid, a mixture of at least one of acetic acid and fluoroacetic acid with anhydrous ethanol or formic acid, and at least one of acetic acid and fluoroacetic acid, ; ^Adding a fluoride of Mn ⁴⁺ to a first mixed solution to obtain a second mixed solution; And a fluoride of A in a second mixed solution to obtain a precipitate to obtain a red luminescent material.

According to an exemplary embodiment of the present invention, the substrate material containing X is selected from the group consisting of an aqueous solution of hexafluorosilicic acid, an aqueous solution of hexafluorotitanic acid, an aqueous solution of hexafluorozirconic acid, (Ammonium hexafluoro germanate). &Lt; / RTI &gt;

According to an exemplary embodiment of the present invention, the mass percentage of the hexafluorosilicic acid aqueous solution, the hexafluorotitanic acid aqueous solution or the hexafluorozirconic acid aqueous solution may be 30 to 50%.

According to an exemplary embodiment of the present invention, the volume ratio of at least one of formic acid, acetic acid, and fluoroacetic acid to anhydrous ethanol may be 1 to 100: 1.

According to an exemplary embodiment of the present invention, the fluoride of Mn ⁴⁺ may comprise one of Potassium hexafluoro mangeate and Sodium heparafluoro mannate.

According to an exemplary embodiment of the present invention, the fluoride of A may comprise at least one of Sodium fluoride, Potassium fluoride, Rubidium fluoride and Cesium fluoride.

According to an exemplary embodiment of the present invention, the step of mixing a substrate material containing X with a reaction solvent includes mixing a substrate material containing X and a reaction solvent at room temperature and uniformly stirring to obtain a first mixed solution . &Lt; / RTI &gt;

In accordance with the illustrative embodiment of the invention, the steps for loading a fluoride of Mn ⁴⁺ to the first mixed solution is stirred after inserting a fluoride of Mn ⁴⁺ to the first mixture for 20 to 60 minutes to obtain a second mixed solution Step &lt; / RTI &gt;

According to an exemplary embodiment of the present invention, the step of putting the fluoride of A into the second mixed solution may include a step of adding the fluoride of A to the second mixed solution and stirring for 1 to 12 hours to obtain a precipitate.

According to an exemplary embodiment of the present invention, the method may further comprise washing and drying the precipitate to obtain a red luminescent material.

According to the method of the present invention, since the red light emitting material excited by blue light is produced without using hydrofluoric acid, the method of the present invention does not affect environmental pollution.

In addition, according to the method of the present invention, the appearance of the red light emitting material prepared using a mixture of at least one of formic acid, acetic acid, and fluoroacetic acid with anhydrous ethanol or at least one of formic acid, acetic acid, and fluoroacetic acid as a reaction solvent It is uniform.

Besides, the manufacturing process according to the method of the present invention is simple, easy to operate, and applied to large scale industrial production.

In addition, the red light emitting material produced according to the method of the present invention has a strong red light emission peak (for example, the emission peak is located at about 627 nm or 632 nm) under blue light excitation, Excellent purity; The emission spectrum color coordinate value of the obtained red light emitting material is close to the color coordinate value x = 0.67, y = 0.33 of the ideal red light.

1 is a flow chart of a method of manufacturing a red light emitting material according to an exemplary embodiment of the present invention;
2 is an XRD diffraction diagram of Na ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 1 of the present invention;
3 is a chart of the room temperature excitation spectrum (monitoring wavelength is 627 nm) and emission spectrum (excitation wavelength is 460 nm) of Na ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 1 of the present invention;
4 is an electroluminescence spectrogram of an LED device made of Na ₂ TiF ₆ : Mn ⁴⁺ and a blue light LED chip obtained in Example 1 of the present invention under excitation of 20 mA current;
5 is an XRD diffraction diagram of Na ₂ SiF ₆ : Mn ⁴⁺ obtained in Example 2 of the present invention;
6 is a ^chart of the room temperature excitation spectrum (monitoring wavelength is 627 nm) and emission spectrum (excitation wavelength is 460 nm) of Na ₂ SiF ₆ : Mn ⁴⁺ obtained in Example 2 of the present invention;
7 is an electroluminescence spectrogram of an LED device made of Na ₂ SiF ₆ : Mn ⁴⁺ and a blue light LED chip obtained in Example 2 of the present invention under excitation of 20 mA current;
8 is an XRD diffraction diagram of K ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 3 of the present invention;
9 is a chart of the room temperature excitation spectrum (monitoring wavelength is 632 nm) and emission spectrum (excitation wavelength is 460 nm) of K ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 3 of the present invention;
10 is an electroluminescence spectrogram of an LED device made of K ₂ TiF ₆ : Mn ⁴⁺ and a blue light LED chip obtained in Example 3 of the present invention under excitation of 20 mA current;
11 is an XRD diffraction diagram of K ₂ GeF ₆ : Mn ⁴⁺ obtained in Example 4 of the present invention;
12 is a chart of the room temperature excitation spectrum (monitoring wavelength is 631 nm) and emission spectrum (excitation wavelength is 460 nm) of K ₂ GeF ₆ : Mn ⁴⁺ obtained in Example 4 of the present invention;
13 is an electroluminescence spectrogram of an LED device made of K ₂ GeF ₆ : Mn ⁴⁺ and a blue light LED chip obtained in Example 4 of the present invention under excitation of 20 mA current;
14 is an XRD diffraction diagram of Rb ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 5 of the present invention;
15 is a chart of the room temperature excitation spectrum (monitoring wavelength is 631 nm) and the emission spectrum (excitation wavelength is 465 nm) of Rb ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 5 of the present invention;
16 is an electroluminescence spectrogram of an LED device made of Rb ₂ TiF ₆ : Mn ⁴⁺ and a blue light LED chip obtained in Example 5 of the present invention under excitation of 20 mA current;
17 is an XRD diffraction diagram of Cs ₂ ZrF ₆ : Mn ⁴⁺ obtained in Example 6 of the present invention;
18 is a chart of a room temperature excitation spectrum (monitoring wavelength is 630 nm) and emission spectrum (excitation wavelength is 480 nm) of Cs ₂ ZrF ₆ : Mn ⁴⁺ obtained in Example 6 of the present invention; And
19 is an electroluminescence spectrogram of an LED device made of Cs ₂ ZrF ₆ : Mn ⁴⁺ and a blue light LED chip obtained in Example 6 of the present invention under excitation of 20 mA current.

BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the technical solution of the present invention, the principles of the present invention will now be described in more detail by way of example embodiments.

In the prior art, a red light emitting material is prepared using hydrofluoric acid as a reaction solvent, but the use of a large amount of hydrofluoric acid causes environmental pollution. On the basis thereof, the present invention provides a method for producing a red light emitting material without using hydrofluoric acid.

There is provided a method of manufacturing a red light emitting material according to an exemplary embodiment of the present invention, wherein a chemical composition of a red light emitting material can be expressed by the following equation (1)

&Quot; (1) &quot;

A ₂ X _1-y F _6: yMn ⁴⁺

In the formula (1), A is at least one selected from alkali metal elements; X is at least one selected from Ti, Si, Ge and Zr; y represents the molar percentage coefficient of the ion for the Mn ⁴⁺ ion to the X ⁴⁺ ion, and 0 < y? 0.10.

In an exemplary embodiment of the invention, A may be selected from at least one of Na, K, Rb and Cs. Optionally, A may be Na and / or K.

In an exemplary embodiment of the present invention, X may be selected from at least one tetravalent element of Ti, Si, Ge, and Zr. Optionally, X may be Si or Ti.

In the present invention, since the red light emitting material has a structure in which the X component in A ₂ X _{1 -y} F ₆ is partially replaced with Mn ⁴⁺ , such a red light emitting material can be referred to as a Mn-activated fluoride red light emitting material have. The red light emitting material according to the present invention has a strong red light emission peak (for example, the emission peak is located at about 627 nm or about 632 nm) under blue light excitation and has a high luminous efficiency; The emission spectrum color coordinate value of the obtained red light emitting material is close to the color coordinate value x = 0.67, y = 0.33 of the ideal red light.

Hereinafter, a method of manufacturing a red light emitting material excited by blue light will be described in detail with reference to FIG.

1 is a flow chart of a method of manufacturing a red light emitting material excited by blue light according to an exemplary embodiment of the present invention.

Referring to FIG. 1, a method of preparing a red light emitting material excited by blue light according to an exemplary embodiment of the present invention includes mixing a substrate material containing X with a reaction solvent to obtain a first mixed solution (S100 ); ^Adding a fluoride of Mn ⁴⁺ to the first mixed solution to obtain a second mixed solution (S200); Adding a fluoride of A to a second mixed solution to obtain a precipitate (S300); And washing and drying the precipitate to obtain a red light emitting material (S400).

In step (S100) of mixing a substrate material containing X and a reaction solvent, a substrate material containing X and a reaction solvent are mixed under a room temperature condition and uniformly stirred to obtain a first mixed solution. Here, X may be the same as X described above, and will not be described further herein.

In an exemplary embodiment of the present invention, the substrate material containing X may comprise at least one of an aqueous solution of hexafluorosilicic acid, an aqueous solution of hexafluorotitanic acid, an aqueous solution of hexafluorozirconic acid, and ammonium hexafluoroarsenic acid. In addition, in an exemplary embodiment of the present invention, the mass percentage of the hexafluorosilicic acid aqueous solution, the hexafluorotitanic acid aqueous solution, or the hexafluorozirconic acid aqueous solution may be 30 to 50%. In a non-limiting embodiment of the present invention, when ammonium hexafluoroarsenate is used, the ammonium hexafluoroarsenate can be mixed directly with the reaction solvent.

In a non-limiting embodiment of the present invention, the ratio relationship of the substrate material containing X to the reaction solvent is not particularly limited, and the reaction solvent includes any suitable amount capable of completely dissolving the substrate material containing X can do.

In an exemplary embodiment of the invention, the reaction solvent may comprise a mixture of at least one of formic acid, acetic acid, and fluoroacetic acid with anhydrous ethanol or at least one of formic acid, acetic acid, and fluoroacetic acid. Optionally, the reaction solvent is a mixture of formic acid and anhydrous ethanol, a mixture of acetic acid and anhydrous ethanol, a mixture of fluoroacetic acid and anhydrous ethanol, a mixture of formic acid and acetic acid and anhydrous ethanol, a mixture of acetic acid and fluoroacetic acid and anhydrous ethanol, Or a mixture of formic acid and fluoroacetic acid with anhydrous ethanol.

In an exemplary embodiment of the present invention, the volume ratio of at least one of formic acid, acetic acid, and fluoroacetic acid to anhydrous ethanol may be between 1 and 100: 1. Optionally in the range of 5 to 90: 1, 10 to 80: 1, 20 to 70: 1, 30 to 60: 1 or 40 to 50: 1, For example, from 1 to 10: 1.

In the present invention, environmental pollution can be reduced by replacing hydrofluoric acid with a mixture of at least one of formic acid, acetic acid and fluoroacetic acid with anhydrous ethanol or at least one of formic acid, acetic acid and fluoroacetic acid to form a reaction solvent.

In step S200 of introducing the fluoride of Mn ⁴⁺ into the first mixed solution, the fluoride of Mn ⁴⁺ is added to the first mixture and stirred for 20 to 60 minutes to obtain the second mixed solution.

In an exemplary embodiment of the present invention, the fluoride of Mn ⁴⁺ may comprise one of potassium hexafluoromanganate and sodium hexafluoromanganate.

In the present invention, one of potassium hexafluoromanganate and sodium hexafluoromanganate is added to the first mixed solution, and then Mn ⁴⁺ is ion-exchanged with X ⁴⁺ in the first mixed solution. In an exemplary embodiment of the present invention, Mn ⁴⁺ is a luminescent center, its content directly affecting the luminescence efficiency of the sample, if the content is too low, the luminescent efficiency is very low; If the content is too high, the concentration may be lowered and the emission efficiency of the sample may be reduced. Therefore, the content of Mn ⁴⁺ in the light emitting material should be controlled and controlled. In the present invention, the molar ratio of Mn ⁴⁺ to X ⁴⁺ is 0.01 to 0.1: 1.

In step S300 of introducing the fluoride of A into the second mixed solution, the fluoride of A is put into the second mixed solution and stirred for 1 to 12 hours to obtain a precipitate. Here, A may be the same as A described above, and is not further described here.

In an exemplary embodiment of the present invention, the fluoride of A may comprise at least one of sodium fluoride, potassium fluoride, rubidium fluoride, and cesium fluoride.

In the present invention, when the fluoride of A is put into the second mixed solution, the second mixed solution can be precipitated, thereby obtaining a red luminescent material.

In an exemplary embodiment of the present invention, the molar ratio of the fluoride of A to the substrate material containing X may be from 0.5 to 10: 1 and, optionally, from 1 to 9: 1, from 2 to 8: 1, from 3 to 6 : 1 or 4 to 5: 1, or within any range defined by the values set forth above, and may be, for example, 2 to 7: 1. If the amount of fluoride used in A is too small, the sample is difficult to precipitate; If the amount of fluoride used in A is excessively large, other foreign matter is generated and the phase of the sample becomes impure.

In an exemplary drying step S400 of the present invention, the precipitate can be washed with anhydrous methanol or anhydrous ethanol, and dried in vacuum for 10 to 30 hours to obtain a red light emitting material excited by blue light.

In the method of producing the red light emitting material excited by the blue light of the present invention, each step proceeds under room temperature.

In addition, a red light emitting material excited by blue light was obtained by using ion exchange-coprecipitation method without using hydrofluoric acid.

In a non-limiting embodiment of the present invention, the excitation wavelength of the blue light may be between 420 and 480 nm.

The method of producing a red light emitting material excited by blue light according to the present invention can achieve at least one of the following effects.

1. According to the method of the present invention, by producing a red light emitting material excited by blue light without using hydrofluoric acid, the method of the present invention does not affect environmental pollution.

2. According to the method of the present invention, the appearance of the red light-emitting material prepared using a mixture of at least one of formic acid, acetic acid, and fluoroacetic acid with anhydrous ethanol or at least one of formic acid, acetic acid, and fluoroacetic acid as a reaction solvent, Do.

3. The manufacturing process according to the method of the present invention is simple, easy to operate, and applied to large-scale industrialization.

4. The red light emitting material produced according to the method of the present invention has a strong red light emission peak (for example, the emission peak is located at about 627 nm or about 632 nm) under blue light excitation, has a high luminous efficiency, &Lt; / RTI &gt; The emission spectrum color coordinate value of the obtained red light emitting material is close to the color coordinate value x = 0.67, y = 0.33 of the ideal red light.

Hereinafter, a method for producing a red light emitting material excited by blue light according to the present invention will be described in more detail by combining the following embodiments.

Example 1:

2.5 ml of a 50% aqueous hexafluorotitanic acid solution was dissolved in a reaction solvent of 18 ml of formic acid and 2 ml of anhydrous ethanol; 0.12 g of sodium hexafluoromanganate was added and stirred for 20 minutes; Finally, 1.05 g of sodium fluoride is added and stirring is continued for 2 hours. The obtained precipitate was washed several times with anhydrous methanol and dried in a vacuum drying oven for 24 hours to obtain red luminescent material Na ₂ TiF ₆ : Mn ⁴⁺ ; Besides, Mn ⁴⁺ in the sample measured by atomic absorption spectra is 0.049 mol. The results of the detection are shown in Figs.

2 is an XRD diffraction diagram of Na ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 1 of the present invention. 3 is a chart of the room temperature excitation spectrum (monitoring wavelength is 627 nm) and the emission spectrum (excitation wavelength is 460 nm) of Na ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 1 of the present invention. 4 is an electroluminescence spectrogram of an LED device made of Na ₂ TiF ₆ : Mn ⁴⁺ and a blue light LED chip obtained in Example 1 of the present invention under excitation of 20 mA current.

As shown in FIG. 2, when Na ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 1 is compared with the standard card JCPDS 15-0581 (Na ₂ TiF ₆ ), they are completely matched and diffraction of arbitrary impurity phase No peak was observed, indicating that the red light emitting material produced had a single crystal phase.

As shown in Fig. 3, the obtained red light emitting material has strong broadband excitation in both the ultraviolet region and the blue light region. Under the optical excitation at 460 nm, the emission wavelength of the red light emitting material is centered on the red light emission wavelength and the emission wavelength is about 627 nm, which corresponds to a transition of ² E _g to ⁴ A _{2 g} of Mn ⁴⁺ .

4 is a spectrogram obtained by applying the obtained red light emitting material to an LED device on a blue light LED chip and then exciting it under a current of 20 mA. 4, the emission peak of about 460 nm is the blue light emitted from the LED chip. The emission peak of the red light emitting material obtained in the present invention is located in the red light region, and its strongest emission peak is located at 627 nm do.

Example 2:

5 ml of a 30% aqueous hexafluorosilicic acid solution was dissolved in a reaction solvent of 15 g of fluoroacetic acid and 5 ml of anhydrous ethanol; 0.12 g of sodium hexafluoromanganate was added and stirred for 30 minutes; Finally, 1.05 g of sodium fluoride is added and stirring is continued for 4 hours. The obtained precipitate was washed several times with anhydrous methanol and dried in a vacuum drying oven for 24 hours to obtain a red luminescent material Na ₂ SiF ₆ : Mn ⁴⁺ ; Besides, the Mn ⁴⁺ in the sample measured by atomic absorption spectra is 0.041 mol. The results of the detection are shown in Figs.

5 is an XRD diffraction diagram of Na ₂ SiF ₆ : Mn ⁴⁺ obtained in Example 2 of the present invention. 6 is a ^chart of the room temperature excitation spectrum (monitoring wavelength is 627 nm) and emission spectrum (excitation wavelength is 460 nm) of Na ₂ SiF ₆ : Mn ⁴⁺ obtained in Example 2 of the present invention. 7 is an electroluminescence spectrogram of an LED device made of Na ₂ SiF ₆ : Mn ⁴⁺ and a blue light LED chip obtained in Example 2 of the present invention under excitation of 20 mA current.

As shown in FIG. 5, when Na ₂ SiF ₆ : Mn ⁴⁺ obtained in Example 2 was compared with the standard card JCPDS 33-1280, they were completely matched and no diffraction peak of any impurity phase was observed , Indicating that the prepared red light emitting material has a single crystal phase.

As shown in Fig. 6, the obtained red light emitting material has strong broadband excitation in both the ultraviolet region and the blue light region. Under light excitation at 460 nm under 460 nm of light excitation, the emission wavelength of the red luminescent material is centered on the red light emission wavelength and the emission wavelength is about 627 nm, which corresponds to ² E _g to ⁴ A _{2 g} transition of Mn ⁴⁺ .

7 is a spectrogram obtained by applying the obtained red light emitting material to an LED device on a blue light LED chip and then exciting it under a current of 20 mA. 7, the emission peak of about 460 nm is the blue light emitted from the LED chip. The emission peak of the red light emitting material obtained in the present invention is located in the red light region, and its strongest emission peak is located at 627 nm do.

Example 3:

2.5 ml of a 50% aqueous hexafluorotitanic acid solution was dissolved in a reaction solvent of 18 ml of acetic acid and 2 ml of anhydrous ethanol; 0.15 g of potassium hexafluoromanganate was added and stirred for 40 minutes; Finally, 1.52 g of potassium fluoride is added and stirring is continued for 1 hour. The obtained precipitate was washed several times with anhydrous methanol and dried in a vacuum drying oven for 24 hours to obtain a red light emitting material K ₂ TiF ₆ : Mn ⁴⁺ ; Besides, Mn ⁴⁺ in the sample measured by atomic absorption spectra is 0.045 mol. The results of the detection are shown in Figs.

8 is an XRD diffraction diagram of K ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 3 of the present invention. 9 is a chart of the room temperature excitation spectrum (monitoring wavelength is 632 nm) and emission spectrum (excitation wavelength is 460 nm) of K ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 3 of the present invention. 10 is an electroluminescence spectrogram of an LED device made of K ₂ TiF ₆ : Mn ⁴⁺ and a blue light LED chip obtained in Example 3 of the present invention under excitation of 20 mA current.

As shown in Fig. 8, when the K ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 3 was compared with the standard card JCPDS 08-0488, they were completely matched and no diffraction peak of any impurity phase was observed , Indicating that the prepared red light emitting material has a single crystal phase.

As shown in Fig. 9, the obtained red light emitting material has strong broadband excitation in both the ultraviolet light region and the blue light region. Under the optical excitation of 460 nm, the emission wavelength of the red light emitting material is centered on the red light emission wavelength and the emission wavelength is about 632 nm, which corresponds to a transition of ² E _g to ⁴ A _{2 g} of Mn ⁴⁺ .

10 is a spectrogram obtained by applying the obtained red light emitting material to an LED element on a blue light LED chip and then exciting it under a current of 20 mA. 10, the emission peak of about 460 nm is the blue light emitted from the LED chip. The emission peak of the red light emitting material obtained in the present invention is located in the red light region, and its strongest emission peak is located at 632 nm do.

Example 4:

2.21 g of ammonium hexafluoroarsenic ammonium was dissolved in a reaction solvent of 10 g of fluoroacetic acid and 10 ml of anhydrous ethanol; 0.15 g of potassium hexafluoromanganate was added and stirred for 60 minutes; Finally, 2.52 g of potassium fluoride is added and stirring is continued for 12 hours. The obtained precipitate was washed several times with anhydrous methanol and dried in a vacuum drying oven for 24 hours to obtain a red light emitting material K ₂ GeF ₆ : Mn ⁴⁺ ; Besides, Mn ⁴⁺ in the sample measured by atomic absorption spectra is 0.042 mol. The results of the detection are shown in Figs.

11 is an XRD diffraction pattern of K ₂ GeF ₆ : Mn ⁴⁺ obtained in Example 4 of the present invention. 12 is a chart of the room temperature excitation spectrum (monitoring wavelength is 631 nm) and the emission spectrum (excitation wavelength is 460 nm) of K ₂ GeF ₆ : Mn ⁴⁺ obtained in Example 4 of the present invention. 13 is an electroluminescence spectrogram of an LED device made of K ₂ GeF ₆ : Mn ⁴⁺ and a blue light LED chip obtained in Example 4 of the present invention under excitation of 20 mA current.

As shown in FIG. 11, when comparing the K ₂ GeF ₆ : Mn ⁴⁺ obtained in Example 4 with the standard card JCPDS 07-0241, they were completely matched and no diffraction peak of any impurity phase was observed , Indicating that the prepared red light emitting material has a single crystal phase.

As shown in Fig. 12, the obtained red light emitting material has strong broadband excitation in both the ultraviolet light region and the blue light region. Under light excitation at 460 nm under 460 nm of light excitation, the emission wavelength of the red luminescent material is centered on the red light emission wavelength and the emission wavelength is about 631 nm, which corresponds to ² E ^g to ⁴ A _{2 g} transition of Mn ⁴⁺ .

13 is a spectrogram obtained by applying the obtained red light emitting material to an LED element on a blue light LED chip and then exciting it under a current of 20 mA. 13, the emission peak of about 460 nm is the blue light emitted from the LED chip. The emission peak of the red light emitting material obtained in the present invention is located in the red light region, and its strongest emission peak is located at 631 nm do.

Example 5:

2.5 ml of 50% aqueous solution of hexafluorotitanic acid was dissolved in a reaction solvent of 15 ml of formic acid and 5 ml of anhydrous ethanol; 0.12 g of potassium hexafluoromanganate was added and stirred for 30 minutes; Finally, 2.58 g of rubidium fluoride is added and stirring is continued for 3 hours. The obtained precipitate was washed several times with anhydrous methanol and dried in a vacuum drying oven for 24 hours to obtain a red light emitting material Rb ₂ TiF ₆ : Mn ⁴⁺ ; Besides, the Mn ⁴⁺ in the sample measured by atomic absorption spectra is 0.052 mol. The results of the detection are shown in FIG. 14 to FIG.

14 is an XRD diffraction pattern of Rb ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 5 of the present invention. 15 is a chart of the room temperature excitation spectrum (monitoring wavelength is 631 nm) and emission spectrum (excitation wavelength is 465 nm) of Rb ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 5 of the present invention. 16 is an electroluminescence spectrogram of an LED device manufactured from Rb ₂ TiF ₆ : Mn ⁴⁺ and a blue light LED chip obtained in Example 5 of the present invention under excitation of 20 mA current.

As shown in FIG. 14, when Rb ₂ TiF ₆ : Mn ⁴⁺ obtained in Example 5 was compared with the standard card JCPDS 51-0611, they were completely matched and no diffraction peak of any impurity phase was observed , Indicating that the prepared red light emitting material has a single crystal phase.

As shown in Fig. 15, the obtained red light emitting material has a strong broadband excitation in both the ultraviolet light region and the blue light region. Under photoexcitation at 465 nm under 460 nm of light excitation, the emission wavelength of the red light emitting material is centered on the red light emission wavelength and the emission wavelength is about 631 nm, which corresponds to ² E _g to ⁴ A _{2 g} transition of Mn ⁴⁺ .

16 is a spectrogram obtained by applying the obtained red light emitting material to an LED device on a blue light LED chip and then exciting the LED device under a current of 20 mA. 16, the emission peak of about 465 nm is blue light emitted from the LED chip. The emission peak of the red light emitting material obtained in the present invention is located in the red light region, and its strongest emission peak is located at 631 nm do.

Example 6:

3.9 ml of 45% hexafluorozirconic acid aqueous solution was dissolved in a reaction solvent of 15 ml of formic acid and 5 ml of anhydrous ethanol; 0.11 g of potassium hexafluoromanganate was stirred for 30 minutes; Finally, 3.88 g of cesium fluoride is added and stirring is continued for 8 hours. The obtained precipitate was washed several times with anhydrous methanol and dried in a vacuum drying oven for 24 hours to obtain a red light emitting material Cs ₂ ZrF ₆ : Mn ⁴⁺ ; Besides, the Mn ⁴⁺ in the sample measured by atomic absorption spectra is 0.056 mol. The results of the detection are shown in Figs.

17 is an XRD diffraction diagram of Cs ₂ ZrF ₆ : Mn ⁴⁺ obtained in Example 6 of the present invention. 18 is a chart of the room temperature excitation spectrum (monitoring wavelength is 630 nm) and emission spectrum (excitation wavelength is 480 nm) of Cs ₂ ZrF ₆ : Mn ⁴⁺ obtained in Example 6 of the present invention. 19 is an electroluminescence spectrogram of an LED device made of Cs ₂ ZrF ₆ : Mn ⁴⁺ and a blue light LED chip obtained in Example 6 of the present invention under excitation of 20 mA current.

As shown in FIG. 17, when the Cs ₂ ZrF ₆ : Mn ⁴⁺ obtained in Example 6 and the standard card JCPDS 74-0173 were compared with each other, they were completely matched and no diffraction peak of any impurity phase was observed , Indicating that the prepared red light emitting material has a single crystal phase.

As shown in Fig. 18, the obtained red light emitting material has strong broadband excitation in both the ultraviolet light region and the blue light region. Under the light excitation of 460 nm under 480 nm of light excitation, the emission wavelength of the red light emitting material is centered on the red light emission wavelength and the emission wavelength is about 630 nm, which corresponds to ² E _g to ⁴ A _{2 g} transition of Mn ⁴⁺ .

19 is a spectrogram obtained by applying the obtained red light emitting material to an LED element on a blue light LED chip and then exciting it under a current of 20 mA. 19, the emission peak of about 460 nm is the blue light emitted from the LED chip. The emission peak of the red light emitting material obtained in the present invention is located in the red light region, and its strongest emission peak is located at 630 nm do.

As described above, according to the method of the present invention, a mixture of at least one of formic acid, acetic acid, and fluoroacetic acid with a mixture of anhydrous ethanol or a mixture of formic acid, acetic acid, and fluoroacetic acid is used as a reaction solvent. Appearance is uniform. In addition, the red light emitting material produced according to the method of the present invention has a very strong red light emission peak (for example, the emission peak is located at about 627 nm or 632 nm) under blue light excitation, and has a high luminous efficiency.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, those skilled in the art will readily appreciate that many modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents. , And can be varied in form and detail. The embodiments are to be considered in all respects as illustrative and not restrictive. Therefore, the scope of the present invention should not be limited by the specific embodiments of the present invention but should be limited by the claims, and all differences within the range will be construed as being included in the present invention.

Claims (10)

In the method for producing a red light emitting material excited by blue light, the chemical composition of the red light emitting material is A ₂ X _{1 -y} F _6: yMn ⁴⁺ , A is at least one selected from alkali metal elements; X is at least one selected from Ti, Si, Ge and Zr; y represents the molar percentage coefficient of the Mn ⁴⁺ ion relative to the X ⁴⁺ ion, 0 < y? 0.10;
A step of mixing a substrate material containing X with a reaction solvent to obtain a first mixed solution, wherein the reaction solvent comprises at least one of formic acid, a mixture of at least one of acetic acid and fluoroacetic acid and anhydrous ethanol or formic acid, acetic acid and fluoroacetic acid Included -;
^Adding a fluoride of Mn ⁴⁺ to a first mixed solution to obtain a second mixed solution; And
And a step of adding a fluoride of A to a second mixed solution to obtain a precipitate to obtain a red light emitting material.
The method according to claim 1,
The substrate material containing X may be at least one selected from the group consisting of Hexafluorosilicic acid aqueous solution, Hexafluorotitanic acid aqueous solution, Hexafluorozirconic acid aqueous solution and Ammonium hexafluoro Germanate And excited by blue light including at least one of the blue light and the blue light.
3. The method of claim 2,
Wherein the mass ratio of the hexafluorosilicic acid aqueous solution, the hexafluorotitanic acid aqueous solution, or the hexafluorozirconic acid aqueous solution is 30 to 50% by the blue light.
The method according to claim 1,
Wherein the volume ratio of at least one of formic acid, acetic acid, and fluoroacetic acid to anhydrous ethanol is 1 to 100: 1.
The method according to claim 1,
Wherein the fluoride of Mn ⁴⁺ is excited by blue light comprising one of Potassium hexafluoro manganate and Sodium heparafluoro managnetate.
The method according to claim 1,
Wherein the fluoride of A is excited by blue light comprising at least one of sodium fluoride, potassium fluoride, rubidium fluoride and cesium fluoride.
The method according to claim 1,
The step of mixing the substrate material containing X with the reaction solvent comprises:
A method for producing a red light emitting material excited by blue light comprising the step of mixing a substrate material containing X at a room temperature with a reaction solvent and uniformly stirring to obtain a first mixed solution.
The method according to claim 1,
The step of introducing the fluoride of Mn ⁴⁺ into the first mixed solution comprises:
^Adding a fluoride of Mn ⁴⁺ to the first mixture, and stirring the mixture for 20 to 60 minutes to obtain a second mixed solution.
The method according to claim 1,
The step of introducing the fluoride of A into the second mixed solution comprises:
A is added to the second mixed solution, followed by stirring for 1 to 12 hours to obtain a precipitate. The method for producing a red light emitting material excited by blue light.
The method according to claim 1,
And washing and drying the precipitate to obtain a red light emitting material.

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