Mn² + ,Dy³ + ,Tm³ + Preparation process of NaRe(WO4)2 single matrix fluorescent powder

Abstract

This invention discloses Mn² for white LED applications. + ,Dy³ + ,Tm³ + Preparation process of NaRe(WO4)2 single-matrix phosphor, with the general chemical formula: NaRe1- x --2(WO4)2:xTm³ + ,yDy³ + ,zMn² + Where Re is at least one of Y, Gd, and Lu; x is Tm³ + The molar doping concentration is 0.01 ≤ x ≤ 0.08; y is Dy³ + The molar doping concentration is 0.02 ≤ y ≤ 0.15; z is Mn² + With a molar doping concentration of 0.02 ≤ z ≤ 0.12, this Mn²⁺ for white LED applications + ,Dy³ + ,Tm³ + The preparation process of NaRe(WO4)2 single-matrix phosphor involves single-doping Tm³ into the NaRe(WO4)2 matrix. + Dy³ + and Mn² + Under near-ultraviolet chip excitation, a single component can simultaneously generate blue, yellow, and red light, which, when mixed, form white light, completely solving the problems of reabsorption and color shift caused by multiphase phosphor mixing and encapsulation.

Description

Technical Field

[0001] This invention relates to the field of luminescent materials and related products, specifically Mn² for white LED applications. + ,Dy³ + Tm³ + Preparation process of NaRe(WO4)2 single-matrix phosphor. Background Technology

[0002] White LEDs are hailed as the fourth generation of lighting sources due to their small size, long lifespan, energy efficiency, and environmental friendliness. Currently, commercially available white LEDs primarily utilize a combination of blue LED chips and yellow YAG:Ce³ light. + The packaging method uses "phosphor", but this solution has problems such as low color rendering index (Ra<80), high color temperature (cool white light) and poor color reproduction of objects due to lack of red light component, which makes it difficult to meet the needs of high-quality indoor lighting and backlight display.

[0003] To address these issues, a common approach is to use a combination of ultraviolet / near-ultraviolet chips and red, green, and blue phosphors. However, using a mixture of multi-phase phosphors presents several critical drawbacks, including varying aging rates among components, color shift, and severe light reabsorption between different phosphors (e.g., blue light being absorbed by red phosphor), leading to reduced luminous efficiency. Furthermore, the complex encapsulation process for multiphase mixtures increases production costs. Summary of the Invention

[0004] The purpose of this invention is to provide Mn² for white LED applications. + ,Dy³ + Tm³ + A process for preparing NaRe(WO4)2 single-matrix phosphor is proposed to address the problems mentioned in the background section.

[0005] To achieve the above objectives, the present invention provides the following technical solution: Mn² for white LED applications. + ,Dy³ + Tm³ + The preparation process of NaRe(WO4)2 single-matrix phosphor, with the general chemical formula: NaRe1- x - -2(WO4)2:xTm³ + ,yDy³ + ,zMn² + Where Re is at least one of Y, Gd, and Lu; x is Tm³ + The molar doping concentration is 0.01 ≤ x ≤ 0.08; y is Dy³ + The molar doping concentration is 0.02 ≤ y ≤ 0.15; z is Mn² +The molar doping concentration is 0.02≤z≤0.12.

[0006] As a preferred embodiment of the present invention, x = 0.02~0.05, y = 0.05~0.10, and z = 0.04~0.08.

[0007] As a preferred embodiment of the present invention, the phosphor simultaneously generates Tm³ under near-ultraviolet light excitation. + Blue light emission, Dy³ + Yellow light emission and Mn² + The red light emission of Mn² + The red light emission originates from Tm³ + and Dy³ + To Mn² + Energy transfer.

[0008] A method for preparing phosphor, employing a high-temperature solid-state method, includes the following steps: S1. According to the general chemical formula NaRe 1-x- -2 (WO4)2:xTm³ + ,yDy³ + ,zMn² + The sodium source, Re source, tungsten source, thulium source, dysprosium source and manganese source are weighed according to their stoichiometric ratios. S2. Mix and grind the raw materials evenly to obtain the precursor mixture; S3. Pre-calcine the precursor mixture in air at 400-500℃ for 2-4 hours, then grind it after cooling; S4. Sinter the ground material at 900-1100℃ in air for 4-8 hours, then cool, crush, and sieve to obtain the finished product.

[0009] As a preferred embodiment of the present invention, in step S1, the sodium source is Na2CO3 or NaNO3; the Re source is Y2O3, Gd2O3 or Lu2O3; the tungsten source is WO3; the thulium source is Tm2O3; the dysprosium source is Dy2O3; and the manganese source is MnCO3 or MnO2.

[0010] As a preferred embodiment of the present invention, in step S1, the actual amount of sodium source weighed is 2%-5% excess over the stoichiometric ratio to compensate for sodium volatilization during the high-temperature sintering process.

[0011] As a preferred embodiment of the present invention, in step S2, anhydrous ethanol is added as a grinding medium, and wet grinding is performed for 30-60 minutes. After the anhydrous ethanol has completely evaporated, a precursor mixture is obtained.

[0012] As a preferred embodiment of the present invention, in step S4, the high-temperature sintering temperature is 950-1050℃, the holding time is 5-6 hours, and the heating rate is 3-5℃ / min.

[0013] Compared with the prior art, the beneficial effects of the present invention are: This Mn² for white LED applications + ,Dy³ + Tm³ + The preparation process of NaRe(WO4)2 single-matrix phosphor involves single-doping Tm³ into the NaRe(WO4)2 matrix. + Dy³ + and Mn² + Under near-ultraviolet chip excitation, a single component can simultaneously generate blue, yellow, and red light, which, when mixed, form white light, completely solving the problems of reabsorption and color shift caused by multiphase phosphor mixing and encapsulation.

[0014] Clever use of Tm³ + and Dy³ + As a sensitizer, Mn² is directed towards the red light emission center. + Dual energy transfer significantly enhances Mn² + The red light emission intensity at ~610 nm compensates for the lack of red light in traditional white LEDs. Attached Figure Description

[0015] Figure 1 Mn² for white LED applications of the present invention + ,Dy³ + Tm³ + A schematic diagram of the process for preparing NaRe(WO4)2 single-matrix phosphor. Detailed Implementation

[0016] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0017] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0018] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0019] Please see Figure 1 The embodiments provided by the present invention are as follows: Example 1 Mn² for white LED applications + , Dy³ + , Tm³ + NaY(WO4)2 single-matrix phosphor, with the general chemical formula NaY 00 . 83 (WO4)2: 0.03Tm³ + 0.08Dy³ + 0.06Mn² + The preparation steps are as follows: S1. Weigh the raw materials according to the stoichiometric ratio: Na2CO3 (3% excess to compensate for volatilization) 0.534g, Y2O3 1.928g, WO3 9.582g, Tm2O3 0.122g, Dy2O3 0.304g, MnCO3 0.074g; S2. Place the above raw materials in an agate mortar, add 15 mL of anhydrous ethanol, grind for 45 minutes until evenly mixed, and wait for the anhydrous ethanol to completely evaporate. S3. Load the mixture into a corundum crucible, place it in a muffle furnace, heat it to 450°C at 3°C / min in air atmosphere, hold it for 3 hours, and then cool it with the furnace. S4. Grind the pre-burned material again for 25 minutes; S5. Reload the ground material into the corundum crucible, place it in the muffle furnace, heat it to 1000 ℃ at 4 ℃ / min in air atmosphere, hold it for 6 hours, and then cool it to room temperature with the furnace. S6. Grind and pulverize the sintered product, pass it through a 200-mesh sieve, and obtain a white powder, which is the finished product.

[0020] Example 2 The general chemical formula is NaGd 00 . 85 (WO4)2: 0.02Tm³ + 0.05Dy³ + 0.08Mn² +The preparation method is the same as in Example 1, except that the Re source is Gd2O3, the doping ratio of each ion is different, and the sintering temperature in step S5 is 950 ℃, and the holding time is 7 hours.

[0021] Due to Mn² + With increased concentration, the red light component is enhanced, the color coordinates are redder (0.352, 0.325), the color temperature is 4650 K, and the color rendering index Ra=95, making it suitable for medical lighting applications where red light color rendering is extremely important.

[0022] Example 3 The general chemical formula is NaLu 00 . 80 (WO4)2: 0.05Tm³ + , 0.10Dy³ + 0.05Mn² + The preparation method is the same as in Example 1, except that the Re source is Lu2O3, the doping ratio of each ion is different, and the sintering temperature in step S5 is 1050 ℃, and the holding time is 4 hours.

[0023] The blue and yellow light components are relatively enhanced, the color coordinates are (0.295, 0.350), the color temperature is 7200 K, the color rendering index Ra=85, and it is a cool white light, suitable for backlight display applications.

[0024] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. Mn² for white LED applications + ,Dy³ + Tm³ + The preparation process of NaRe(WO4)2 single-matrix phosphor is characterized by: The general chemical formula is: NaRe1- x - -2(WO4)2:xTm³ + ,yDy³ + ,zMn² + Where Re is at least one of Y, Gd, and Lu; x is Tm³ + The molar doping concentration is 0.01 ≤ x ≤ 0.08; y is Dy³ + The molar doping concentration is 0.02 ≤ y ≤ 0.15; z is Mn² + The molar doping concentration is 0.02≤z≤0.

12.

2. The Mn² for white LED applications as described in claim 1 + ,Dy³ + Tm³ + The preparation process of NaRe(WO4)2 single-matrix phosphor is characterized by: The values ​​are x = 0.02~0.05, y = 0.05~0.10, and z = 0.04~0.

08.

3. The Mn² for white LED applications as described in claim 1 + ,Dy³ + Tm³ + The preparation process of NaRe(WO4)2 single-matrix phosphor is characterized by: The phosphor, when excited by near-ultraviolet light, simultaneously generates Tm³ + Blue light emission, Dy³ + Yellow light emission and Mn² + The red light emission of Mn² + The red light emission originates from Tm³ + and Dy³ + To Mn² + Energy transfer.

4. A method for preparing the phosphor according to any one of claims 1-3, characterized in that, The high-temperature solid-state method includes the following steps: S1. According to the general chemical formula NaRe 1-x- -2 (WO4)2:xTm³ + ,yDy³ + ,zMn² + The sodium source, Re source, tungsten source, thulium source, dysprosium source and manganese source are weighed according to their stoichiometric ratios. S2. Mix and grind the raw materials evenly to obtain the precursor mixture; S3. Pre-calcine the precursor mixture in air at 400-500℃ for 2-4 hours, then grind it after cooling; S4. Sinter the ground material at 900-1100℃ in air for 4-8 hours, then cool, crush, and sieve to obtain the finished product.

5. The Mn² for white LED applications according to claim 1 + ,Dy³ + Tm³ + The preparation process of NaRe(WO4)2 single-matrix phosphor is characterized by: In step S1, the sodium source is Na2CO3 or NaNO3; the Re source is Y2O3, Gd2O3 or Lu2O3; the tungsten source is WO3; the thulium source is Tm2O3; the dysprosium source is Dy2O3; and the manganese source is MnCO3 or MnO2.

6. The Mn² for white LED applications according to claim 1 + ,Dy³ + Tm³ + The preparation process of NaRe(WO4)2 single-matrix phosphor is characterized by: In step S1, the actual amount of sodium source weighed is 2%-5% excess over the stoichiometric ratio to compensate for sodium volatilization during the high-temperature sintering process.

7. The Mn² for white LED applications according to claim 1 + ,Dy³ + Tm³ + The preparation process of NaRe(WO4)2 single-matrix phosphor is characterized by: In step S2, anhydrous ethanol is added as a grinding medium and wet-ground for 30-60 minutes. After the anhydrous ethanol has completely evaporated, the precursor mixture is obtained.

8. The Mn² for white LED applications according to claim 1 + ,Dy³ + Tm³ + The preparation process of NaRe(WO4)2 single-matrix phosphor is characterized by: In step S4, the high-temperature sintering temperature is 950-1050℃, and the holding time is 5-6 hours. The heating rate is 3-5℃ / min.

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