CN102618266A - Blue and violet light-excited yellow light fluorescent material and preparation method and application thereof - Google Patents

Abstract

The invention discloses a blue and violet light-excited yellow light fluorescent material. The chemical expression of the blue and violet light-excited yellow light fluorescent material is SrxCa3-1.5n-xAl1-2ySiyMgyO4F, wherein n is more than or equal to 0.005 and less than or equal to 0.1; x is more than or equal to 1.6 and less than or equal to 3-1.5n; and y is more than or equal to 0 and less than or equal to 0.4. In a preparation method of the fluorescent material, Sr3AlO4F is taken as a substrate, Ce is doped for replacing Sr for causing a crystal lattice defect serving as a luminous center, Sr is replaced by Ca, and Al is replaced by Si and Mg, so that the crystal lattice environment is improved, the light color is changed, an exciting main peak waveband is adjustable, and the strength is enhanced. The blue and violet light-excited yellow light fluorescent material disclosed by the invention is safe and nontoxic, has stable chemical property and stable fluorescent performance, and is easy to store for a long time; and the method disclosed by the invention has the advantages of low sintering temperature, simple process, suitability for industrial production and wide application prospect.

Description

Yellow fluorescent material excited by blue-violet light and its preparation method and application

technical field

The invention belongs to the technical field of luminescent materials, and in particular relates to a yellow-light fluorescent material excited by blue-violet light and a preparation method thereof.

Background technique

Since 1993, it took the lead in making breakthroughs in blue GaInN-LED technology, and then introduced white LEDs to the market, which has attracted great attention from insiders and outsiders. Because, compared with traditional lighting sources, white LEDs have many advantages, such as small size, low energy consumption, fast response, long life, and no pollution, so they are called the fourth generation of lighting sources. As the most commonly used commercial blue light excitation LED phosphor, YAG:Ce phosphor needs to use a large amount of rare earths in production, resulting in high cost, lack of red light components in the emission spectrum, and low color rendering index after matching with blue LED chips. These disadvantages greatly limit the application and development of blue light-excited LEDs.

At present, two effective methods to directly improve the fluorescent luminous efficiency are improving the power of the LED chip and modifying the phosphor powder. At present, the emission wavelength of traditional commercialized blue LED chips is between 460nm and 470nm. Due to the limitation of input power, if there is no major breakthrough, there is no room for increase in output power. The newly developed high-power blue-violet LED chip emits at a wavelength of 395-440nm, and its wavelength is shorter, and the power is 1.2 times that of the traditional blue-ray chip under the same energy input. However, the absorption peak of the light conversion material based on the blue LED is mainly required to be located at 440-470nm, and there are very few fluorescent materials that can meet the requirement of blue-violet light excitation at 395-440nm. Traditional blue light excitation phosphors are directly combined with high-power blue-violet light chips. Extremely inefficient due to excitation matching problems.

Therefore, the current main direction of LED research and development is to search for phosphors that can be effectively excited by high-power blue-violet LED chips at 395nm to 440nm. Strontium haloaluminate system as a new fluorescent matrix has been reported as ①Sr _3-x Al ₂ O ₅ Cl ₂ :Eux red light ②Sr _2.975 Ce _0.025 AlO ₄ F blue light ③Sr _2.975-x Ba/Ca _x Ce _0.025 AlO4F green light Light ④Sr ₃ AlO ₄ F:RE ³⁺ (RE=Tm/Tb, Eu, Ce) red, green, blue light. ⑤Sr ₃ Al _0.9 In _0.1 O _4-R F _1-δ self-activated blue-green light. Yellow light emission is rarely seen, and the intensity is too low to be commercially applied. In this patent, the strontium fluoroaluminate (Sr ₃ AlO ₄ F) matrix with a cubic structure can be adjusted from 405 nm to 430 nm by replacing Sr with Ca; the emission wavelength can be adjusted from 515 to 430 nm after Si-Mg is replaced by Al doping modification 545nm. The final product is a yellow fluorescent material with a main peak excited at 430nm and a broadband emission at 545nm. It has high chemical and thermal stability, color rendering and temperature quenching effect, and can be excited efficiently at 395nm-440nm. Compared with commercial YAG, the process requirements are simpler and the sintering temperature is lower. After matching with the blue-violet LED chip, the light color is 4500K white light, which is more warm white than the commercial YAG phosphor 9000K. The invention may be used as an important coating powder for white LED chips excited by blue-violet light, and fills the gap in this field.

Contents of the invention

The object of the present invention is to address the defects of the prior art, to propose a safe, stable chemical property, easy long-term preservation, and stable fluorescent performance of phosphor, and to provide a new phosphor material with low cost, simple process and suitable for industrial production. Preparation.

In order to achieve the above object, the present invention adopts the following technical solutions:

A yellow light fluorescent material excited by blue-violet light is characterized in that its chemical expression is as follows:

Sr _x Ca _3-1.5nx Al _1-2y Si _y Mg _y O ₄ F:nCe, wherein 0.005≤n≤0.1, 1.6≤x≤3-1.5n, 0≤y≤0.4, preferably, n=0.02, 1.8≤x≤2.8, 0.1≤y≤0.4.

The preparation method of the yellow fluorescent material excited by the above-mentioned blue-violet light, the specific steps are as follows:

1) Weigh according to the stoichiometric ratio of Sr, Ca, Al, Si, Mg, F and Ce elements in Sr _x Ca _3-1.5nx Al _1-2y Si _y Mg _y O ₄ F:nCe: strontium salt, fluoride strontium, calcium salts, aluminum oxide, silicon dioxide, magnesium oxide and cerium oxide;

2) Grinding and mixing the above-mentioned raw materials evenly at room temperature;

3) Under N ₂ /H ₂ atmosphere, raise the temperature to 900°C-1300°C at a rate of 3-4°C, keep the temperature for 4-8h, and grind again to obtain the target product.

Step 1) The strontium salt is selected from one or both of strontium carbonate and strontium nitrate, and the calcium salt is selected from one or both of calcium carbonate and calcium nitrate.

In step 2), absolute ethanol is added to assist in grinding, and the material powder is dried after grinding; the amount of absolute ethanol added is 20% to 50% of the mass of the mixture.

The N ₂ /H ₂ atmosphere in step 3) is preferably 95% N ₂ /5% H ₂ , and the holding time is preferably 5 h.

The inorganic fluorescent material prepared by the above scheme is based on Sr ₃ AlO ₄ F as the matrix, the lattice defects are formed by replacing Sr with Ce as the luminescent center, and the Sr in the matrix is replaced by Ca, and the Al in the matrix is replaced by Si and Mg to form a eutectic , to improve the lattice environment, so that the light color changes, the excitation main peak band can be adjusted, and the intensity can be increased. The material obtained by the invention has uniform and fine particle size, stable chemical, optical and thermal properties, and can be used for yellow light and white light LEDs.

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

1) The excitation wavelength of the obtained fluorescent material is 400nm-440nm, which is well matched with the 430nm purple LED chip; the emission peak is 500nm-570nm; after matching, the color temperature can be adjusted from 5300K to 4500K, the absorption efficiency is good and the performance is stable, and the The fluorescence intensity at ℃ is 88% of that at room temperature, with excellent temperature quenching effect and color rendering; compared with the commercial YAG phosphor 9000K, it is more warm white light, adding a new variety to blue-violet light-excited yellow light-emitting materials; (these should be illustrated in the corresponding graph in the examples)

2) The product of the present invention adopts the grinding method combined with the _H2 reduction method, the sintering temperature is low, and the fine and efficient long-wave band excitation fluorescent powder material can be obtained with a little grinding, which is safe, non-toxic, stable in chemical properties, easy to store for a long time, and stable in fluorescence performance and other beneficial effects;

3) The preparation process of the present invention is simple and easy to operate, the raw materials are cheap and easy to obtain, there is no industrial waste in the reaction process, it has the characteristics of low sintering temperature, energy saving, etc., and is suitable for industrial production, especially its blue-violet light excitation performance makes the material have a wide range of application prospects.

Description of the drawings (see the attached drawings for the modification description)

FIG. 1 is a fluorescence spectrum diagram of the yellow fluorescent material excited by blue-violet light prepared in Examples 1-3.

Fig. 2 is the X-ray diffraction pattern of the fluorescence of the blue-violet light-excited yellow fluorescent material prepared in Examples 1-16 and the Sr ₃ AlO ₄ F standard card JCPDS No. 89-4485.

3 is a fluorescence spectrum diagram of the blue-violet light-excited yellow fluorescent material prepared in Example 3 and the commercial YAG phosphor powder excited at a wavelength of 430 nm.

Fig. 4 is the fluorescence spectrum diagram of the yellow fluorescent material excited by blue-violet light prepared in Examples 2, 4, 5 and 6.

Fig. 5 is the fluorescence spectrum diagram of the yellow fluorescent material excited by blue-violet light prepared in Examples 3, 7, 8, 9 and 10.

FIG. 6 is a graph showing the performance test of the blue-violet light-excited yellow fluorescent material prepared in Example 3 and commercial YAG with respect to the temperature-decay test.

7 is a graph showing the stability test of the blue-violet light-excited yellow fluorescent material prepared in Example 3 with respect to ultraviolet-natural sunlight-fluorescence intensity.

Fig. 8 is a fluorescence spectrum diagram of yellow fluorescent materials excited by blue-violet light prepared in Example 3 and Examples 11-16.

Fig. 9 is a comparison diagram of the peak intensity of the highest emission peak of the fluorescence spectrum of yellow fluorescent materials excited by blue-violet light prepared in Example 3 and Examples 11-16.

FIG. 10 is a graph of color coordinates and color temperature of commercial YAG and yellow fluorescent materials excited by blue-violet light prepared in Example 2 and Example 3.

Detailed ways

Below in conjunction with specific embodiment, further illustrate the present invention.

Example 1:

The preparation method of the yellow fluorescent material excited by blue-violet light provided in this example, the specific steps are as follows:

(1) Weigh 3.6465g (24.7mmol) SrCO ₃ , 0.6281g (5mmol) SrF ₂ and 0.5098g (5mmol) Al ₂ O ₃ , 0.03442g (0.2mmol) CeO ₂ , the doping ratio is Sr: Ce = 297 : 2;

(2) In a fume hood, mix the above precursors, add 50% absolute ethanol of the total mass of the sample, grind and mix;

(3) drying at 80°C in a blast oven;

(4) Put the above precursors into a tube furnace, raise the temperature to 1200°C at a rate of 3-4°C/min in a 95% N ₂ /5% H ₂ atmosphere, and continue sintering at 1200°C for 5 hours. obtain the target product.

(1) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

Example 2:

The preparation method of this example is the same as that described in Example 1, except that in step 1) 0.1020g (1mmol) Al ₂ O ₃ , 0.2403g (4mmol) SiO ₂ and 0.1612g (4mmol) MgO are used to replace 0.5098 g (5 mmol) Al ₂ O ₃ .

(2) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

Example 3:

The preparation method of this embodiment is the same as that described in Example 1, except that in step 1), 1.8749g (12.7mmol) _SrCO3 and 1.20108g (12mmol) _CaCO3 are used to replace 3.6465g (24.7mmol) _SrCO3 ; 0.1020 g (1 mmol) Al ₂ O ₃ , 0.2403 g (4 mmol) SiO ₂ and 0.1612 g (4 mmol) MgO replaced 0.5098 g (5 mmol) Al ₂ O ₃ .

(3) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

Fig. 1 is the fluorescence spectrogram of the yellow fluorescent material excited by blue-violet light prepared in Examples 1 to 3; From the figure, it can be seen that the main peak of excitation wavelength of the material prepared in Example 1: 405nm; the main peak of emission wavelength: 460nm; the main peak of emission wavelength: 460nm; The main peak of excitation wavelength of the obtained material: 424nm; the main peak of emission wavelength: 545nm; the main peak of excitation wavelength of the material prepared in Example 3: 430nm; the main peak of emission wavelength: 545nm. It can be proved that the presence of Si and Mg can replace Al in the matrix, improve the lattice environment, change the light color, adjust the main excitation peak band, and increase the intensity; Ca can replace Sr in the matrix to redshift the excitation wavelength.

Fig. 3 is the fluorescence spectrogram of the blue-violet light-excited yellow fluorescent material prepared in this example and the commercial YAG phosphor under excitation at a wavelength of 430nm. It can be seen that the blue-violet light-excited yellow fluorescent material prepared in this example is more fluorescent than YAG Powder has a better matching ability for long-wave ultraviolet chips.

Example 4:

The preparation method of this example is _the same _as that described in Example ₁ , except that in step 1), 0.5098 g (5 mmol) Al ₂ O ₃ .

The fluorescence spectrum of the yellow fluorescent material excited by blue-violet light prepared in this example is shown in Fig. 4; it can be seen from the figure that the main peak of the excitation wavelength is 424nm; the main peak of the emission wavelength is 527nm.

(4) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

Example 5

The preparation method of this example is the same as that described in Example 1, except that in step 1) 0.3768g (3mmol) Al ₂ O ₃ , 0.1202g (2mmol) SiO ₂ and 0.0806g (2mmol) MgO are used to replace 0.5098 g (5 mmol) Al ₂ O ₃ .

The fluorescence spectrum of the yellow fluorescent material excited by the blue-violet light prepared in this embodiment is shown in Fig. 4; it can be seen from the figure that the main peak of the excitation wavelength is 424nm; the main peak of the emission wavelength is 523nm.

(5) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

Example 6

The preparation method of this example is the same as that described in Example 1, except that in step 1) 0.4078g (4mmol) Al ₂ O ₃ , 0.0601g (1mmol) SiO ₂ and 0.0403g (1mmol) MgO are used to replace 0.5098 g (5 mmol) Al ₂ O ₃ .

The fluorescence spectrum of the yellow fluorescent material excited by blue-violet light prepared in this example is shown in Fig. 4; it can be seen from the figure that the main peak of the excitation wavelength is 424nm; the main peak of the emission wavelength is 520nm.

(6) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

It can be seen from Figure 4 that by increasing the proportion of Si-Mg replacing Al and improving its internal covalency, the emission band can be obviously red-shifted to the long wavelength direction, and the intensity can also be significantly improved.

Example 7

The preparation method of this embodiment is the same as that described in Example 1, except that in step 1), 2.1702g (14.7mmol) _SrCO3 and 1.0008g (10mmol) _CaCO3 are used to replace 3.6465g (24.7mmol) _SrCO3 ; 0.5098 g (5 mmol) of Al ₂ O 3 was replaced by 0.1020 g (1 mmol) _of Al 2 O ₃ , 0.2403 g (4 mmol) _of SiO ₂ and 0.1612 g (4 mmol) of MgO.

The fluorescence spectrum of the yellow fluorescent material excited by the blue-violet light prepared in this embodiment is shown in Fig. 5; it can be seen from the figure that the main peak of the excitation wavelength is 423nm; the main peak of the emission wavelength is 545nm.

(7) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

Example 8

The preparation method of this embodiment is the same as that described in Example 1, except that in step 1), 2.4654g (16.7mmol) _SrCO3 and 0.8006g (8mmol) _CaCO3 are used to replace 3.6465g (24.7mmol) _SrCO3 ; 0.5098 g (5 mmol) of Al ₂ O 3 was replaced by 0.1020 g (1 mmol) _of Al 2 O ₃ , 0.2403 g (4 mmol) _of SiO ₂ and 0.1612 g (4 mmol) of MgO.

The fluorescence spectrum of the yellow fluorescent material excited by blue-violet light prepared in this example is shown in Fig. 5; it can be seen from the figure that the main peak of the excitation wavelength is 420nm; the main peak of the emission wavelength is 545nm.

(8) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

Example 9

The preparation method of this embodiment is the same as that described in Example 1, except that in step 1), 2.7607g (18.7mmol) _SrCO3 and 0.6005g (6mmol) _CaCO3 are used to replace 3.6465g (24.7mmol) _SrCO3 ; 0.1020 g (1 mmol) Al ₂ O ₃ , 0.2403 g (4 mmol) SiO ₂ and 0.1612 g (4 mmol) MgO replaced 0.5098 g (5 mmol) Al ₂ O ₃ .

The fluorescence spectrum of the yellow fluorescent material excited by blue-violet light prepared in this example is shown in Fig. 5; it can be seen from the figure that the main peak of the excitation wavelength is 418nm; the main peak of the emission wavelength is 545nm.

(9) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

Example 10

The preparation method of this example is the same as that described in Example 1, except that 3.0559g (20.7mmol) SrCO3 and _0.4004g (4mmol) _CaCO3 are used in step 1) to replace 3.6465g (24.7mmol) _SrCO3 ; 0.1020 g (1 mmol) Al ₂ O ₃ , 0.2403 g (4 mmol) SiO ₂ and 0.1612 g (4 mmol) MgO replaced 0.5098 g (5 mmol) Al ₂ O ₃ .

The fluorescence spectrum of the yellow fluorescent material excited by blue-violet light prepared in this embodiment is shown in Fig. 5; it can be seen from the figure that the main peak of the excitation wavelength is 416nm; the main peak of the emission wavelength is 545nm.

(10) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

It can be seen from Figure 5 that by replacing Sr in the original matrix with Ca with a smaller radius and changing the lattice size, the excitation band can be broadened and red-shifted, and the intensity can also be significantly increased.

Example 11:

The preparation method of this example is the same as that described in Example 1, except that in step 1) 1.9081g (12.925mmol) SrCO ₃ , 0.008605g (0.05mmol) CeO ₂ and 1.20108g (12mmol) CaCO ₃ are replaced 3.6465g (24.7mmol) SrCO ₃ and 0.03442g (0.2mmol) CeO ₂ ; 0.1020g (1mmol) Al ₂ O ₃ , 0.2403g (4mmol) SiO ₂ and 0.1612g (4mmol) MgO replaced 0.5098g (5mmol) Al ₂ O ₃ .

The fluorescence spectrum of the yellow fluorescent material excited by blue-violet light prepared in this example is shown in Fig. 8; it can be seen from the figure that the main peak of the excitation wavelength is 416nm; the main peak of the emission wavelength is 545nm.

(11) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

Example 12:

The preparation method of this example is the same as that described in Example 1, except that in step 1) 1.89705g (12.85mmol) SrCO ₃ , 0.01721g (0.1mmol) CeO ₂ and 1.20108g (12mmol) CaCO ₃ are replaced 3.6465g (24.7mmol) SrCO ₃ and 0.03442g (0.2mmol) CeO ₂ ; 0.1020g (1mmol) Al ₂ O ₃ , 0.2403g (4mmol) SiO ₂ and 0.1612g (4mmol) MgO replaced 0.5098g (5mmol) Al ₂ O ₃ .

The fluorescence spectrum of the yellow fluorescent material excited by blue-violet light prepared in this example is shown in Fig. 8; it can be seen from the figure that the main peak of the excitation wavelength is 416nm; the main peak of the emission wavelength is 545nm.

(12) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

Example 13:

The preparation method of this example is the same as that described in Example 1, except that in step 1) 1.8306g (12.4mmol) SrCO ₃ , 0.06884g (0.4mmol) CeO ₂ and 1.20108g (12mmol) CaCO ₃ are used instead 3.6465g (24.7mmol) SrCO ₃ and 0.03442g (0.2mmol) CeO ₂ ; 0.1020g (1mmol) Al ₂ O ₃ , 0.2403g (4mmol) SiO ₂ and 0.1612g (4mmol) MgO replaced 0.5098g (5mmol) Al ₂ O ₃ .

The fluorescence spectrum of the yellow fluorescent material excited by blue-violet light prepared in this example is shown in Fig. 8; it can be seen from the figure that the main peak of the excitation wavelength is 416nm; the main peak of the emission wavelength is 545nm.

(13) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

Example 14:

The preparation method of this example is the same as that described in Example 1, except that in step 1) 1.7863g (12.1mmol) SrCO ₃ , 0.10326g (0.6mmol) CeO ₂ and 1.20108g (12mmol) CaCO ₃ are used instead 3.6465g (24.7mmol) SrCO ₃ and 0.03442g (0.2mmol) CeO ₂ ; 0.1020g (1mmol) Al ₂ O ₃ , 0.2403g (4mmol) SiO ₂ and 0.1612g (4mmol) MgO replaced 0.5098g (5mmol) Al ₂ O ₃ .

The fluorescence spectrum of the yellow fluorescent material excited by blue-violet light prepared in this example is shown in Fig. 8; it can be seen from the figure that the main peak of the excitation wavelength is 416nm; the main peak of the emission wavelength is 545nm.

(14) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

Example 15:

The preparation method of this example is the same as that described in Example 1, except that in step 1) 1.74203g (11.8mmol) SrCO ₃ , 0.13768g (0.8mmol) CeO ₂ and 1.20108g (12mmol) CaCO ₃ are used instead 3.6465g (24.7mmol) SrCO ₃ and 0.03442g (0.2mmol) CeO ₂ ; 0.1020g (1mmol) Al ₂ O ₃ , 0.2403g (4mmol) SiO ₂ and 0.1612g (4mmol) MgO replaced 0.5098g (5mmol) Al ₂ O ₃ .

The fluorescence spectrum of the yellow fluorescent material excited by blue-violet light prepared in this example is shown in Fig. 8; it can be seen from the figure that the main peak of the excitation wavelength is 416nm; the main peak of the emission wavelength is 545nm.

(15) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

Example 16:

The preparation method of this example is the same as that described in Example 1, except that in step 1), 1.69775g (11.5mmol) SrCO ₃ , 0.1721g (1mmol) CeO ₂ and 1.20108g (12mmol) CaCO ₃ are used to replace 3.6465 g (24.7mmol) SrCO ₃ and 0.03442g (0.2mmol) CeO ₂ ; 0.1020g (1mmol) Al ₂ O ₃ , 0.2403g (4mmol) SiO ₂ and 0.1612g (4mmol) MgO to replace 0.5098g (5mmol) Al ₂ O ₃ .

The fluorescence spectrum of the yellow fluorescent material excited by the blue-violet light prepared in this example is shown in Fig. 8, from which it can be seen that the main peak of the excitation wavelength is 416nm; the main peak of the emission wavelength is 545nm.

(16) in FIG. 2 is the X-ray diffraction pattern of the yellow fluorescent material excited by blue-violet light prepared in this embodiment.

It can be seen from Fig. 2 that the materials prepared in Examples 1-16 have the same lattice structure as Sr ₃ AlO ₄ F, and there are no obvious raw material phases and non-target product phases.

It can be seen from Figure 6 that the half-life temperature quenching point has not been reached at 250°C, and the temperature decay resistance performance is greatly improved compared with commercial YAG phosphors.

It can be seen from Figure 7 that the intensity remains basically unchanged after being irradiated by ultraviolet light and sunlight, indicating that it can remain stable under ultraviolet light and sunlight.

It can be seen from Fig. 8 that in the range of nCe addition 0.005≤n≤0.1, the brightness reaches the highest when n=0.02, and the Ce concentration is the concentration quenching point of the phosphor at this time.

It can be seen intuitively from FIG. 9 that in Example 3, that is, when the addition amount of nCe=0.02, the fluorescence intensity reaches the maximum. When the concentration is higher than or lower than this concentration, due to the concentration quenching effect; the energy transfer distance is too far, resulting in a decrease in fluorescence intensity.

It can be seen from Figure 10 that compared with the commercial YAG phosphor 9000K, it is more inclined to warm white light, which adds a new variety to blue-violet light-excited yellow light-emitting materials.

In addition, experiments have proved that: the inorganic salt of the doping element may be a combination of strontium nitrate, aluminum nitrate, calcium nitrate, cerium nitrate, and strontium fluoride in any proportion.

The above-mentioned embodiments should be understood as only for illustrating the present invention but not for limiting the protection scope of the present invention. After reading the contents of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent changes and modifications also fall within the scope defined by the claims of the present invention.

Claims (8)

1. the light activated gold-tinted fluorescent material of royal purple is characterized in that its chemical expression is following: Sr _xCa _3-1.5n-xAl _1-2ySi _yMg _yO ₄F:nCe, 0.005≤n≤0.1,1.6≤x≤3-1.5n wherein, 0≤y≤0.4.

2. the light activated gold-tinted fluorescent material of royal purple is characterized in that n=0.02,1.8≤x≤2.8,0.1≤y≤0.4.

3. the preparation method of claim 1 or the light activated yellow fluorescent material of 2 described royal purple is characterized in that concrete steps are following:

1) according to Sr _xCa _3-1.5n-xAl _1-2ySi _yMg _yO ₄The stoichiometric ratio of Sr, Ca, Al, Si, Mg, F and Ce element takes by weighing among the F:nCe: strontium salt, strontium fluoride, calcium salt, aluminium sesquioxide, silicon-dioxide, Natural manganese dioxide and cerium oxide;

2) at ambient temperature that the above-mentioned raw materials ground and mixed is even;

3) at N ₂/ H ₂Under the atmosphere, be warming up to 900 ℃～1300 ℃ with 3～4 ℃ speed, insulation 4～8h, regrinding promptly obtains title product.

4. the preparation method of the light activated yellow fluorescent material of the described royal purple of claim 3 is characterized in that, the said strontium salt of step 1) is selected from one or both in Strontium carbonate powder and the strontium nitrate, and said calcium salt is selected from one or both in lime carbonate and the nitrocalcite.

5. the preparation method of the light activated yellow fluorescent material of the described royal purple of claim 3 is characterized in that step 2) in, add absolute ethyl alcohol and assist to grind, oven dry material powder after grinding is accomplished.

6. the preparation method of the light activated yellow fluorescent material of the described royal purple of claim 5 is characterized in that, the add-on of absolute ethyl alcohol is 20～50% of a mixture quality.

7. the preparation method of the light activated yellow fluorescent material of the described royal purple of claim 3 is characterized in that, the gas atmosphere in the step 3) is 95%N ₂/ 5%H ₂Atmosphere, soaking time are 5h.

8. claim 1 or the light activated yellow fluorescent material of 2 described royal purple are in the application in gold-tinted and white light LEDs field.

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