Sodium-rich titanium-based garnet red-light fluorescent powder and preparation method thereof

Abstract

The invention discloses red light NaGd2Ga2InTi2O12: Sm < 3 + > fluorescent powder and a preparation method thereof. The invention relates to red light NaGd2Ga2InTi2O12: Sm < 3 + > fluorescent powder, the chemical composition expression formula of which is NaGd2 (1-x) Ga2InTi2O12: 2xSm < 3 >, and x is less than or equal to 0.10. The invention provides red light NaGd2Ga2InTi2O12: Sm < 3 + > fluorescent powder and a preparation method thereof. The red light NaGd2Ga2InTi2O12: Sm < 3 + > fluorescent powder can be efficiently excited by 400-410 nm near ultraviolet light and 455-475 nm blue light, emits red light with the strongest main peak being 616 nm, simultaneously emits multi-peak narrow-band light in the range from 565-660 nm orange to dark red light, and has the color coordinate being (0.59, 0.41) and the fluorescence lifetime being in the magnitude of 1 millisecond.

Description

Technical Field

[0001] The present invention relates to the technical field of luminescent materials, in particular to a red light emitting NaGd2Ga2InTi2O 12 :Sm 3+ Phosphor and preparation method thereof. Background Art

[0002] As the quality of life improves, people's requirements for the quality of indoor light sources are also increasing. 3+ The color rendering index of the white light source designed by garnet phosphor is low, and the ability to render the true color of the illuminated object is weak. The root cause is that the spectrum coverage of the red light region in the white light source is insufficient. The simplest way to improve this problem is to add additional red light components to the spectrum. Therefore, the acquisition of new red light phosphors has always been the focus of research in this field. 3+ It is an activator of common inorganic red phosphors. In many inorganic compound systems composed of different elements, efficient narrow-band luminescence in the spectral region from orange to red can be obtained. However, if you want to obtain high-quality red light that is conducive to improving the color rendering index, Sm 3+ The position and peak ratio of the main emission peak in the matrix compound are very important. 3+ The red light peak should be concentrated in the wavelength range of 600-630nm. If the wavelength is shorter than 600nm, the luminous color will be orange and cannot fully supplement the lack of red light components in the spectrum. If the wavelength is greater than 630nm, the luminous color is red, but it is too far from the visually perceptible high-sensitivity center area, the perceptible luminous intensity decreases, and the lumen efficiency cannot be taken into account. 3+ There are many reports on garnet-based phosphors as activators, including Y3Al5O 12 :Sm 3+ 、Y3Ga5O 12 :Sm 3+ But in these Sm 3+ In activated garnet-based phosphors, 4 G 5 / 2 - 6 H 7 / 2 The optimal red light peak corresponding to the transition not only accounts for a low proportion, but also has a weak excitation intensity in the blue light region. In terms of spectral performance, it is difficult to fully supplement the red light in practical applications and improve the color rendering ability of the corresponding light-emitting device. In addition, the reported samarium garnet-based phosphors also face many problems that are not conducive to actual industrial applications, such as high synthesis temperature (>1400℃), high requirements for production equipment, high cost of raw materials of the elements involved, and poor economic benefits. Summary of the invention

[0003] The present invention provides a red light NaGd2Ga2InTi2O 12 :Sm 3+ phosphor and a preparation method thereof. The red light NaGd2Ga2InTi2O 12 :Sm 3+ phosphor can be efficiently excited by near-ultraviolet light of 400 - 410 nm and blue light of 455 - 475 nm, emits red light with the strongest main peak at 616 nm, and is accompanied by multi-peak narrow-band luminescence in the orange to deep red light region of 565 - 660 nm. The color coordinates are located at (0.59, 0.41), and the fluorescence lifetime is on the order of 1 millisecond.

[0004] The object of the present invention is to propose a red light NaGd2Ga2InTi2O 12 :Sm 3+ phosphor, and its chemical composition representation formula is: NaGd 2(1-x) Ga2InTi2O 12 :2xSm 3 , where: 0 < x ≤ 0.10.

[0005] Another object of the present invention is to propose a preparation method of the above-mentioned red light NaGd2Ga2InTi2O 12 :Sm 3+ phosphor, including the following steps: Weigh raw materials containing sodium, gadolinium, gallium, indium, titanium and samarium elements according to the chemical composition. Among them, the molar ratio of each element is Na:Gd:Ga:In:Ti:Sm = 1:2 - 2x:2:1:2:2x, where: 0 < x ≤ 0.10. During the synthesis process, 10% of Ga2O3 and 10% of In2O3 need to be additionally added to compensate for the loss of Ga and In during the high-temperature reaction. Grind them充分均匀混合 and put them into a reaction vessel, sinter in an atmospheric air atmosphere, and then cool to room temperature. Grind the product to obtain the above-mentioned red light NaGd2Ga2InTi2O 12 :Sm 3+ phosphor.

[0006] The red light NaGd2Ga2InTi2O 12 :Sm 3+ phosphor proposed by the present invention充分利用了 Sm 3+ 在含钠富钛石榴石基质中强烈的 4 G 5 / 2 - 6 H 7 / 2 跃迁获取高品质红光。本发明提出的红光NaGd2Ga2InTi2O 12 :Sm 3 +Phosphors, using a new garnet matrix constructed with sodium, titanium, gallium, and indium, have a significantly lower reaction temperature for solid-phase synthesis compared to the traditional garnet isomorphic system containing aluminum, silicon, and alkaline earth metals, and the synthesis process has no specific pressure or atmosphere requirements; compared to the traditional germanium-containing garnet isomorphic system, it is more economical in terms of reactant raw material costs.

[0007] Preferably, the raw material containing sodium element is selected from one or more of sodium carbonate, sodium bicarbonate and sodium oxalate.

[0008] Preferably, the raw material containing the gadolinium element is selected from at least one of gadolinium oxide, gadolinium oxalate, gadolinium carbonate and gadolinium nitrate.

[0009] Preferably, the raw material containing gallium element is selected from gallium oxide.

[0010] Preferably, the raw material containing the indium element is selected from indium oxide.

[0011] Preferably, the raw material containing titanium element is selected from titanium oxide.

[0012] The raw material containing samarium element is selected from at least one of samarium oxide, samarium oxalate, samarium carbonate and samarium nitrate.

[0013] Preferably, the sintering procedure is as follows: heating from room temperature to 1100-1300° C. at a rate of 5° C. / min, and maintaining the temperature constant for 3-5 hours after heating.

[0014] The present invention also protects the above-mentioned near-infrared NaGd2Ga2InTi2O 12 :Sm 3+ Application of phosphor in light-emitting devices. The near-infrared phosphor proposed by the present invention has a wide effective excitation range and a wide emission coverage range, and can be applied in the fields of health lighting, plant lighting, temperature detection, infrared recognition, etc.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] (1) The red light NaGd2Ga2InTi2O 12 :Sm 3+ The phosphor can be sintered in one step at a temperature as low as 1100°C and only needs 3-5 hours of reaction to form a phase. It has good crystallinity, high luminous brightness, and short fluorescence lifetime. It can be used as a red light material excited by ultraviolet, near-ultraviolet, and blue light LED chips.

[0017] (2) The red light NaGd2Ga2InTi2O 12 :Sm 3+Phosphors have the advantages of a wide excitation range, excellent red light peak position, cheap raw materials, simple manufacturing process, short synthesis time, low energy consumption, and easy industrialization.

[0018] (3) The red light NaGd2Ga2InTi2O 12 :Sm 3+ Phosphor red NaGd2Ga2InTi2O 12 :Sm 3+ The phosphor can be efficiently excited by 400-410nm near-ultraviolet light and 455-475nm blue light, emitting red light with the strongest main peak at 616nm, accompanied by multi-peak narrow-band luminescence in the orange to deep red light region of 565-660nm. The color coordinates are at (0.59, 0.41), and the fluorescence lifetime is on the order of 1 millisecond. It can be used in many fields such as full-spectrum healthy lighting, fluorescent temperature measurement, and fluorescent anti-counterfeiting. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The red light NaGd2Ga2InTi2O prepared in Example 1 12 :Sm 3+ X-ray powder diffraction pattern of

[0020] Figure 2 The red light NaGd2Ga2InTi2O prepared in Example 1 12 :Sm 3+ Fluorescence emission spectrum of phosphors;

[0021] Figure 3 The red light NaGd2Ga2InTi2O prepared in Example 1 12 :Sm 3+ Fluorescence excitation spectrum of phosphors;

[0022] Figure 4 The red light NaGd2Ga2InTi2O prepared in Example 1 12 :Sm 3+ Chromaticity coordinates of phosphor.

[0023] Figure 5 The red light NaGd2Ga2InTi2O prepared in Example 1 12 :Sm 3+ Fluorescence decay curve of phosphor. DETAILED DESCRIPTION

[0024] The following examples are provided to further illustrate the present invention, but are not intended to limit the present invention. Unless otherwise specified, the equipment and reagents used in the present invention are conventional commercial products in the art.

[0025] Example 1

[0026] Weigh 0.0265g of sodium carbonate (Na2CO3), 0.1722g of gadolinium oxide (Gd2O3), 0.1031g of gallium oxide (Ga2O3), 0.0763g of indium oxide (In2O3), 0.0799g of titanium oxide (TiO2), and 0.0087g of samarium oxide (Sm2O3) respectively, grind the above raw materials in an agate mortar, grind them evenly, and then conduct solid phase reaction. After heating to 1200℃ at a rate of 5℃ / min under normal pressure air atmosphere, keep the temperature constant for 4h, wait for it to cool after the end, grind it evenly to obtain red light NaGd2Ga2InTi2O 12 :Sm 3+ Phosphor.

[0027] Example 2

[0028] Weigh 0.0265g of sodium carbonate (Na2CO3), 0.1722g of gadolinium oxide (Gd2O3), 0.1031g of gallium oxide (Ga2O3), 0.0763g of indium oxide (In2O3), 0.0799g of titanium oxide (TiO2), and 0.0087g of samarium oxide (Sm2O3) respectively, grind the above raw materials in an agate mortar, grind them evenly, and then conduct solid phase reaction. After heating to 1100℃ at a rate of 5℃ / min under normal pressure air atmosphere, keep the temperature constant for 5h, wait for it to cool after the end, grind it evenly to obtain red light NaGd2Ga2InTi2O 12 :Sm 3+ Phosphor.

[0029] Example 3

[0030] Weigh 0.0265g of sodium carbonate (Na2CO3), 0.1722g of gadolinium oxide (Gd2O3), 0.1031g of gallium oxide (Ga2O3), 0.0763g of indium oxide (In2O3), 0.0799g of titanium oxide (TiO2), and 0.0087g of samarium oxide (Sm2O3) respectively, grind the above raw materials in an agate mortar, grind them evenly, and then conduct solid phase reaction. After heating to 1300℃ at a rate of 5℃ / min under normal pressure air atmosphere, keep the temperature constant for 3h, wait for it to cool after the end, grind it evenly to obtain red light NaGd2Ga2InTi2O 12 :Sm 3+ Phosphor.

[0031] Example 4

[0032] Weigh 0.0265g of sodium carbonate (Na2CO3), 0.1631g of gadolinium oxide (Gd2O3), 0.1031g of gallium oxide (Ga2O3), 0.0763g of indium oxide (In2O3), 0.0799g of titanium oxide (TiO2), and 0.0173g of samarium oxide (Sm2O3) respectively, grind the above raw materials in an agate mortar, grind them evenly, and then conduct solid phase reaction. After heating to 1250℃ at a rate of 5℃ / min under normal pressure air atmosphere, keep the temperature constant for 4h, wait for it to cool after the end, grind it evenly to obtain red light NaGd2Ga2InTi2O 12 :Sm 3+ Phosphor.

[0033] Example 5

[0034] Weigh 0.0265g of sodium carbonate (Na2CO3), 0.1631g of gadolinium oxide (Gd2O3), 0.1031g of gallium oxide (Ga2O3), 0.0763g of indium oxide (In2O3), 0.0799g of titanium oxide (TiO2), and 0.0173g of samarium oxide (Sm2O3) respectively, grind the above raw materials in an agate mortar, grind them evenly, and then conduct solid phase reaction. After heating to 1250℃ at a rate of 5℃ / min under normal pressure air atmosphere, keep the temperature constant for 4h, wait for it to cool after the end, grind it evenly to obtain red light NaGd2Ga2InTi2O 12 :Sm 3+ Phosphor.

[0035] Example 6

[0036] Weigh 0.0265g of sodium carbonate (Na2CO3), 0.1794g of gadolinium oxide (Gd2O3), 0.1031g of gallium oxide (Ga2O3), 0.0763g of indium oxide (In2O3), 0.0799g of titanium oxide (TiO2), and 0.0017g of samarium oxide (Sm2O3) respectively, grind the above raw materials in an agate mortar, grind them evenly, and then conduct solid phase reaction. After heating to 1250℃ at a rate of 5℃ / min under normal pressure air atmosphere, keep the temperature constant for 4h, wait for it to cool after the end, grind it evenly to obtain red light NaGd2Ga2InTi2O 12 :Sm 3+ Phosphor.

[0037] Example 7

[0038] Weigh 0.0420g of sodium bicarbonate (NaHCO3), 0.1794g of gadolinium oxide (Gd2O3), 0.1031g of gallium oxide (Ga2O3), 0.0763g of indium oxide (In2O3), 0.0799g of titanium oxide (TiO2), and 0.0017g of samarium oxide (Sm2O3) respectively, grind the above raw materials in an agate mortar, grind them evenly, and then conduct solid phase reaction. After heating to 1150℃ at a rate of 5℃ / min under normal pressure air atmosphere, keep the temperature constant for 5h, wait for it to cool after the end, grind it evenly to obtain red light NaGd2Ga2InTi2O 12 :Sm 3+ Phosphor.

[0039] Example 8

[0040] Weigh 0.0420g of sodium bicarbonate (NaHCO3), 0.1794g of gadolinium oxide (Gd2O3), 0.1031g of gallium oxide (Ga2O3), 0.0763g of indium oxide (In2O3), 0.0799g of titanium oxide (TiO2), and 0.0017g of samarium oxide (Sm2O3) respectively, grind the above raw materials in an agate mortar, grind them evenly, and then conduct solid phase reaction. After heating to 1300℃ at a rate of 5℃ / min under normal pressure air atmosphere, keep the temperature constant for 3h, wait for it to cool after the end, grind it evenly to obtain red light NaGd2Ga2InTi2O 12 :Sm 3+ Phosphor.

[0041] The above are only preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be based on the scope defined by the claims. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A red light NaGd2Ga2InTi2O 12 :Sm 3+ Phosphor, its chemical composition is expressed as: NaGd 2(1-x) Ga2InTi2O 12 :2xSm 3+ ,in: 0<x≤0.10。 2. The red light NaGd2Ga2InTi2O according to claim 1 12 :Sm 3+ The method for preparing phosphor is characterized in that: It includes the following steps: Weigh the raw materials containing sodium, gadolinium, gallium, indium, titanium and samarium elements according to their chemical compositions respectively. Among them, the molar ratio of each element is Na:Gd:Ga:In:Ti:Sm = 1:2 - 2x:2:1:2:2x, where 0 < x ≤ 0.

10. During the synthesis process, 10% of Ga2O3 and 10% of In2O3 need to be additionally added to compensate for the loss of Ga and In during the high-temperature reaction. Grind them充分研磨使其混合均匀 and put them into a reaction vessel, sinter them in an atmospheric air atmosphere, and then cool them to room temperature. Grind the product to obtain the red light NaGd2Ga2InTi2O 12 :Sm 3+ phosphor. It should be noted that there is an unclear part "充分研磨使其混合均匀" in the original Chinese text. I have tried to translate it as best as possible while keeping the context. If there is a more accurate expression for this part, it can be adjusted accordingly.

3. The red light NaGd2Ga2InTi2O according to claim 2 12 :Sm 3+ The method for preparing phosphor is characterized in that: The raw material containing sodium element is selected from one or more of sodium carbonate, sodium bicarbonate and sodium oxalate.

4. The red light NaGd2Ga2InTi2O according to claim 2 12 :Sm 3+ The method for preparing phosphor is characterized in that: The raw material containing gadolinium element is selected from one or more of gadolinium oxide, gadolinium oxalate, gadolinium carbonate and gadolinium nitrate.

5. The red light NaGd2Ga2InTi2O according to claim 2 12 :Sm 3+ The method for preparing phosphor is characterized in that: The raw material containing gallium element is selected from gallium oxide.

6. The red light NaGd2Ga2InTi2O according to claim 2 12 :Sm 3+ The method for preparing phosphor is characterized in that: The raw material containing indium element is selected from indium oxide.

7. The red light NaGd2Ga2InTi2O according to claim 2 12 :Sm 3+ The method for preparing phosphor is characterized in that: The raw material containing titanium element is selected from titanium oxide.

8. The red light NaGd2Ga2InTi2O according to claim 2 12 :Sm 3+ The method for preparing phosphor is characterized in that: The raw material containing samarium element is selected from one or more of samarium oxide, samarium oxalate, samarium carbonate and samarium nitrate.

9. The red light NaGd2Ga2InTi2O according to claim 2 12 :Sm 3+ The method for preparing phosphor is characterized in that: The specific sintering steps are: only one-step sintering, the temperature is 1100-1300°C, the time is 3-5h, the heating rate is 5°C / min, and the use of Ga2O3 and In2O3 in the reaction process requires a superstoichiometric ratio to compensate for the loss of Ga and In during the high-temperature reaction.

10. The red light NaGd2Ga2InTi2O according to claim 1 12 :Sm 3+ Application of phosphors in light-emitting devices.

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