阅读说明：本技术 一种窄带发射绿色氮化物荧光材料及其制备方法和应用 (Narrow-band emission green nitride fluorescent material and preparation method and application thereof ) 是由 解荣军 李淑星 于 2020-05-27 设计创作，主要内容包括：本发明涉及一种窄带发射绿色氮化物荧光材料及其制备方法和应用,所述窄带发射绿色氮化物荧光材料的制备原料由按照重量百分比计的以下组分组成：26.3％≤Si-(3)N-(4)粉体＜100％,0＜Al-(2)O-(3)粉体≤44.7％,0＜AlN粉体≤18.0％,0＜Eu-(2)O-(3)粉体≤11％,所述窄带发射绿色氮化物荧光材料的化学组成为Si-(6-z)Al-(z)O-(z-2y)N-(8-z+2y):yEu(0<z≤4.2,0<y≤0.1),发射光谱峰位位于530-545nm,半峰宽位于45-55nm,中位粒径尺寸小于500nm,在Micro-LED显示领域具有巨大的应用潜力,有望用于实现高分辨率的Micro-LED显示。(The invention relates to a narrow-band emission green nitride fluorescent material and a preparation method and application thereof, wherein the preparation raw materials of the narrow-band emission green nitride fluorescent material comprise the following components in percentage by weight: si of more than or equal to 26.3 percent 3 N 4 Powder is less than 100 percent and Al is more than 0 2 O 3 Not more than 44.7 percent of powder, not more than 0 and not more than 18.0 percent of AlN powder, and not more than 0 and more than Eu 2 O 3 The powder is less than or equal to 11 percent, and the chemical composition of the narrow-band green emitting nitride fluorescent material is Si 6‑z Al z O z‑2y N 8‑z+2y :yEu(0<z≤4.2，0<y is less than or equal to 0.1), the peak position of the emission spectrum is located at 530-545nm, the half-peak width is located at 45-55nm, the median particle size is less than 500nm, the application potential in the Micro-LED display field is huge, and the method is expected to be used for realizing high resolutionMicro-LED display.)

1. A preparation raw material of a narrow-band green emitting nitride fluorescent material is characterized in that: the preparation raw materials of the narrow-band emission green nitride fluorescent material comprise the following components in percentage by weight: si of more than or equal to 26.3 percent₃N₄Powder is less than 100 percent and Al is more than 0₂O₃Not more than 44.7 percent of powder, not more than 0 and not more than 18.0 percent of AlN powder, and not more than 0 and more than Eu₂O₃The powder is less than or equal to 11 percent.

2. The starting material for preparing a narrow-band green nitride fluorescent material according to claim 1, wherein: the grain diameter of each powder is micron, submicron or nanometer.

3. The starting material for preparing a narrow-band green nitride fluorescent material according to claim 1 or 2, wherein: the preparation raw materials of the narrow-band emission green nitride fluorescent material comprise the following components in percentage by weight: si of 60% or more₃N₄Powder is less than 100 percent and Al is more than 0₂O₃Powder is less than or equal to 20 percent, AlN powder is more than 0 and less than or equal to 15 percent, and Eu is more than 0₂O₃The powder is less than or equal to 5 percent.

4. A preparation method of a narrow-band green emitting nitride fluorescent material is characterized by comprising the following steps: the preparation method comprises the steps of mixing the preparation raw materials of the narrow-band green nitride fluorescent material emitting in the narrow band of any one of claims 1 to 3, sintering at high temperature in a nitrogen atmosphere, and carrying out ball milling treatment on the sintered product.

5. The method for preparing a narrow-band green nitride fluorescent material according to claim 4, wherein: the pressure of the nitrogen atmosphere is 0.1-3MPa, the temperature of high-temperature sintering is 1850-2000 ℃, and the heat preservation time is 2-6 h;

optionally, the ball milling treatment comprises putting the sintered product into a high-energy ball mill, selecting silicon nitride pellets and alcohol solution as ball milling media, wherein the mass content of the ball milling media is 30-70 wt%, the ball milling time is 5-20h, and the ball milling speed is 500-1500 rpm.

6. The method for preparing a narrow-band green nitride fluorescent material according to claim 4 or 5, wherein: and performing at least one of surface coating, modification or grading treatment on the ball-milled product to improve the optical performance of the material.

7. A narrow-band green emitting nitride fluorescent material prepared by sintering the preparation raw material of any one of claims 1 to 3 by a high-temperature solid-phase reaction method or by the preparation method of any one of claims 4 to 6, wherein the narrow-band green emitting nitride fluorescent material is characterized in that: the narrow-band green emitting nitride fluorescent material has the chemical composition of Si_6-zAl_zO_z-2yN_8-z+2yyEu, wherein 0<z≤4.2，0<y≤0.1。

8. The narrow-band green nitride fluorescent material according to claim 7, characterized in that: the median particle size of the narrow-band emission green nitride fluorescent material is less than 500 nm;

optionally, the peak position of the emission spectrum of the narrow-band green nitride emission fluorescent material is located at 530-545nm, and the half-peak width is located at 45-55 nm.

9. Use of the narrow-band emissive green nitride fluorescent material according to claim 7 or 8 in Micro-LED displays.

10. A light-emitting device comprising an excitation light source and the narrow-band emission green nitride fluorescent material according to claim 7 or 8, wherein: the excitation light source is a blue light Micro-LED array with the emission wavelength of 440-460 nm.

Technical Field

The invention relates to a fluorescent material, in particular to a narrow-band green emitting nitride fluorescent material and a preparation method and application thereof.

Background

Micro-LEDs (Light-emitting diodes, LEDs) have become one of the most potential display technologies by virtue of the advantages of ultra-low power consumption, ultra-high resolution, ultra-high color saturation, and the like, and are an important component of the ultra-high definition display industry technology in China. At present, the huge transfer of chips is the most important technical bottleneck in practical application of Micro-LED display, and the production efficiency and the product yield are greatly reduced. The technical scheme of obtaining full-color light emission by using the blue light Micro-LED and the fluorescent material (the batch integration of blue light Micro-LED chips is realized by adopting a flip-chip structure packaging and driving IC attaching mode), skillfully avoids mass transfer, and is considered as the optimal alternative scheme for Micro-LED display.

In the technical scheme of 'blue light Micro-LED + fluorescent material', the fluorescent material is one of the most key core materials, and the fluorescent material most expected to be used for Micro-LED display at present is a semiconductor quantum dot and a rare earth doped inorganic fluorescent material. However, the semiconductor quantum dots have the disadvantages of high toxicity, poor stability, short service life, difficulty in mass production and the like, and the practical application of the semiconductor quantum dots in the display field is greatly limited. Rare earth Eu²⁺The doped beta-SiAlON has the characteristics of high luminescent color purity, high quantum yield, good reliability and the like, but the beta-SiAlON is Eu²⁺The particle size of the composite material is usually 10-50 micrometers, and the composite material can be applied to Micro-LED display with the chip spacing smaller than 30 micrometers only by preparing the composite material into a nano-scale, so that a Micro-LED display device with uniform light color can be obtained.

As can be seen from the prior art, research teams at home and abroad make an important progress in the aspect of size control of fluorescent materials. For example, chinese patent publication No. CN1730606A provides a self-combustion preparation method of spherical yttrium silicate nano-phosphor; the Chinese patent with the publication number of CN104357046A provides a preparation method of nano hollow structure silicate-based fluorescent powder; the Chinese invention patent with the publication number of CN101368098A provides a YVO₄:Eu³⁺/YPO₄Core-shell structure nano fluorescent powder and a preparation method thereof; the Chinese patent with the publication number of CN106635007A provides a preparation method of ultra-small-scale rare earth doped yttrium oxide-based nano fluorescent powder; the Chinese patent with the authorization number of CN102061166B provides a preparation method of superfine Sialon luminescent powder. However, the above methods are mainly wet chemical methods, and are mainly suitable for oxide luminescent material systems, and the synthesized samples have poor crystallinity, low phase purity, poor luminescent properties, complex synthesis process, and poor universality.

Disclosure of Invention

The invention aims to overcome the problem that the existing nano fluorescent material is difficult to prepare, and provides a preparation method of a narrow-band green nitride fluorescent material.

The invention also provides a preparation method of the narrow-band green emitting nitride fluorescent material, which comprises mixing, sintering and ball milling. The sintered product is subjected to ball milling, and the cutting design can be carried out on the particle size of the fluorescent material according to different application requirements on the basis of ensuring the excellent optical performance of the high-temperature sintered fluorescent material.

The invention provides a universal method for preparing a nano-scale nitride system luminescent material, the particle size distribution of the prepared nano-scale nitride powder is narrow, and the nitride system fluorescent powder has narrow half-peak width of an emission spectrum and high color purity, so that the nitride system fluorescent powder can be used for Micro-LED display to realize ultra-high resolution future display.

The invention also protects the narrow-band emission green nitride fluorescent material, and the chemical composition is Si6-zAlzOz-2yN8-z +2y: yEu, wherein z is more than 0 and less than or equal to 4.2, and y is more than 0 and less than or equal to 0.1. The material has an emission spectrum peak at 530-545nm, a half-peak width at 45-55nm, a narrow half-peak width and high color purity, and the median particle size is less than 500nm, can be prepared into a uniform fluorescence conversion film, has huge application potential in the Micro-LED display field, and is expected to be used for realizing high-resolution Micro-LED display.

The invention also protects the application of the narrow-band emission green nitride fluorescent material in Micro-LED display, has huge application potential, and is expected to be used for realizing high-resolution Micro-LED display.

Finally, the invention also protects a light-emitting device which comprises an excitation light source and the narrow-band green-emitting nitride fluorescent material.

The specific scheme is as follows:

the preparation raw material of the narrow-band green nitride fluorescent material comprises the following components in percentage by weightThe following components: si of more than or equal to 26.3 percent₃N₄Powder is less than 100 percent and Al is more than 0₂O₃Not more than 44.7 percent of powder, not more than 0 and not more than 18.0 percent of AlN powder, and not more than 0 and more than Eu₂O₃The powder is less than or equal to 11 percent.

Furthermore, the particle size of each powder is micron, submicron or nanometer.

Further, the preparation raw materials of the narrow-band green nitride fluorescent material comprise the following components in percentage by weight: si of 60% or more₃N₄Powder is less than 100 percent and Al is more than 0₂O₃Powder is less than or equal to 20 percent, AlN powder is more than 0 and less than or equal to 15 percent, and Eu is more than 0₂O₃The powder is less than or equal to 5 percent.

The invention also provides a preparation method of the narrow-band emission green nitride fluorescent material, which comprises the steps of mixing the preparation raw materials of the narrow-band emission green nitride fluorescent material, sintering at high temperature in a nitrogen atmosphere, and carrying out ball milling treatment on a sintered product.

Further, the pressure of the nitrogen atmosphere is 0.1-3MPa, the temperature of high-temperature sintering is 1850-2000 ℃, and the heat preservation time is 2-6 h;

optionally, the ball milling treatment comprises putting the sintered product into a high-energy ball mill, selecting silicon nitride pellets and alcohol solution as ball milling media, wherein the mass content of the ball milling media is 30-70 wt%, the ball milling time is 5-20h, and the ball milling speed is 500-1500 rpm.

Further, the method also comprises at least one of surface coating, modification or grading treatment of the ball-milled product to improve the optical performance of the material.

The invention also provides a narrow-band emission green nitride fluorescent material which is prepared by sintering the preparation raw materials by a high-temperature solid-phase reaction method or by the preparation method, wherein the chemical composition of the narrow-band emission green nitride fluorescent material is Si_6-zAl_zO_z-2yN_8-z+2yyEu, wherein 0<z≤4.2，0<y≤0.1。

Further, the median particle size of the narrow-band green nitride emission fluorescent material is less than 500 nm;

optionally, the peak position of the emission spectrum of the narrow-band green nitride emission fluorescent material is located at 530-545nm, and the half-peak width is located at 45-55 nm.

The invention also protects the application of the narrow-band green-emitting nitride fluorescent material in Micro-LED display.

The invention also provides a light-emitting device, which comprises an excitation light source and the narrow-band emission green nitride fluorescent material, wherein the excitation light source is a blue light Micro-LED array with the emission wavelength of 440-.

Has the advantages that:

the invention utilizes a high-energy ball milling method to prepare the nano-scale narrow-band-emission Si_6-zAl_zO_z-2yN_8-z+2y:yEu(0<z≤4.2，0<y is less than or equal to 0.1), overcomes the defect that Si can not be controlled from a synthesis angle_6-zAl_zO_z-2yN_8-z+2yyEu the difficulty of grain size, and the method for obtaining Si with controllable grain size distribution_6-zAl_zO_z-2yN_8-z+2y:yEu(0<z≤4.2，0<y is less than or equal to 0.1) nano green fluorescent material.

On the other hand, in order to avoid the quenching effect of the surface defects of the nano fluorescent particles obtained by ball milling on fluorescence, the quantum yield of the nano fluorescent particles can be improved by surface modification.

The small-particle-size narrow-band-emission Si provided by the invention_6-zAl_zO_z-2yN_8-z+2y:yEu(0<z≤4.2，0<y is less than or equal to 0.1), simple operation and easy mass production.

Drawings

In order to illustrate the technical solution of the present invention more clearly, the drawings will be briefly described below, and it is apparent that the drawings in the following description relate only to some embodiments of the present invention and are not intended to limit the present invention.

FIG. 1 shows narrow-band emitted Si according to examples 1 to 8 of the present invention_6-zAl_zO_z-2yN_8-z+2y:yEu(0<z≤4.2，0<y is less than or equal to 0.1) the particle size distribution curve of the green fluorescent material;

FIG. 2 shows narrow-band hair of examples 1 to 8 of the present inventionIrradiated Si_6-zAl_zO_z-2yN_8-z+2y:yEu(0<z≤4.2，0<y is less than or equal to 0.1) the emission spectrum of the green fluorescent material under the excitation of blue light;

FIG. 3 shows Si with nanometer-scale and narrow-band emission in example 6 of the present invention_6-zAl_zO_z-2yN_8-z+2y:yEu(0<z≤4.2，0<y is less than or equal to 0.1) a topography of the green fluorescent material;

FIG. 4 shows a nanometer-scale, narrow-band emitted Si in accordance with example 6 of the present invention_6-zAl_zO_z-2yN_8-z+2y:yEu(0<z≤4.2，0<y is less than or equal to 0.1) preparing a real image of the green fluorescent film;

FIG. 5 is a diagram of nanoscale, narrow-band emissive Si of the present invention_6-zAl_zO_z-2yN_8-z+2y:yEu(0<z≤4.2，0<y is less than or equal to 0.1) the green fluorescent film is used for the Micro-LED display.

Detailed Description

The definitions of some of the terms used in the present invention are given below, and other non-mentioned terms have definitions and meanings known in the art:

fluorescent material: is prepared from sulfide of metal (Zn, Cr, etc.) or rare-earth oxide and trace activator through calcining. The prepared fluorescent material is nitride, and the preparation raw materials comprise the following components in percentage by weight: si₃N₄Powder (26.3 wt% or more and less than 100) and Al₂O₃Powder (more than 0 wt% and less than or equal to 44.7), AlN powder (more than 0 wt% and less than or equal to 18.0), Eu₂O₃Powder (more than 0 wt% and less than or equal to 11). Preferably, Si₃N₄Powder (60 wt% or more and less than 100) and Al₂O₃Powder (0 < wt% is less than or equal to 20), AlN powder (0 < wt% is less than or equal to 15), Eu₂O₃Powder (0 wt% is less than or equal to 5). In the raw materials, the components are mixed according to the stoichiometric ratio of a target product, wherein Eu₂O₃The powder provides a luminescence center Eu.

The green nitride fluorescent material can be produced by mixing the above raw materials in a conventional manner and then performing the conventional high-temperature sintering reaction. Preferably, the particle size of each powder is micron, submicron or nanometer. The high-temperature reaction is preferably carried out under nitrogen protection in an atmosphere of normal pressure or slightly positive pressure, for example, 0.1 to 3MPa, preferably 0.5 to 1.5MPa, and more preferably 0.8 to 1 MPa. The temperature of the high-temperature sintering is 1600-2000 ℃, and the heat preservation time is 2-6 h; preferably 1800 ℃ and 2000 ℃, more preferably 1900 ℃ and 1950 ℃.

In the invention, the sintered product is subjected to ball milling treatment, preferably, the sintered product is placed into a high-energy ball mill, silicon nitride spheres and alcohol solution are selected as ball milling media, the mass content of the ball milling media is 30-70 wt%, the ball milling time is 5-20h, and the ball milling rotation speed is 500-1500 rpm. The effect brought by the ball milling treatment is that large aggregates obtained by high-temperature sintering are dispersed, and further, micron-sized large grains obtained by high-temperature sintering are crushed into nano-sized small grains. In the high-energy ball milling and crushing process, the quantum efficiency of a ball-milled product can be influenced by the fact that the surface is not crystallized, the defects are increased and the like caused by crushing, but a sintered product formed by the comprehensive action of raw material powder in the sintering step has excellent optical performance, so that the disadvantage of later crushing can be overcome.

In the invention, in order to avoid the quenching effect of the surface defects of the nano fluorescent particles obtained by ball milling on fluorescence, the quantum yield of the nano fluorescent particles can be improved by surface modification. The ball-milled product may be further subjected to at least one of acid washing, surface coating/modification or classification to improve the optical properties of the material. Wherein, the acid cleaning is to remove the amorphous layer on the surface in the ball milling process by using inorganic acid such as dilute hydrochloric acid, hydrofluoric acid and the like; the surface is coated/modified by coating SiO on the surface₂/Al₂O₃The nano-layer and the like suppress adverse effects of surface defects on light emitting properties.

In the invention, the narrow-band green emitting nitride fluorescent material has the chemical composition of Si_6-zAl_zO_z-2yN_8-z+2yyEu, wherein 0<z≤4.2，0<y is less than or equal to 0.1. Eu is a doping element and is used as a luminescence center. Preferably, 0<z≤2，0<y is 0.05 or less, and more preferably 0<z≤0.75，0<y.ltoreq.0.02, e.g. Si_5.875Al_0.125O_0.105N_7.8950.01Eu, e.g. Si_5.75Al_0.25O_0.23N_7.770.01Eu, e.g. Si_5.25Al_0.75O_0.73N_7.27:0.01Eu。

In the invention, the emission spectrum peak of the narrow-band green nitride emission fluorescent material is positioned at 530-545nm, and the half-peak width is positioned at 45-55 nm. The peak position of the emission spectrum is preferably 530-540nm, more preferably 535-540nm, such as 535nm, such as 538nm, such as 540 nm. The half-peak width is preferably 45-50nm, such as 45nm, such as 46nm, such as 47 nm.

Preferred embodiments of the present invention will be described in more detail below. While the following describes preferred embodiments of the present invention, it should be understood that the present invention may be embodied in various forms and should not be limited by the embodiments set forth herein. The examples do not specify particular techniques or conditions, and are performed according to the techniques or conditions described in the literature in the art or according to the product specifications. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products commercially available. In the following examples, "%" means weight percent, unless otherwise specified.

Example 1

Weighing Si according to the weight percentage in the table 1₃N₄Powder of Al₂O₃Powder, AlN powder and Eu₂O₃The powder is used as a starting material, and each raw material is micron-sized powder (0.1-1 micron). Sintering at 1900 ℃ for 4 hours under the atmosphere of nitrogen with 1MPa, cooling, taking out a sample from the furnace, grinding, putting into a high-energy ball mill, selecting silicon nitride spheres and alcohol solution as ball milling media, and performing ball milling to obtain the narrow-band emission green nitride fluorescent material. Specifically, the mass content of the ball milling medium is 30-70 wt%, the ball milling time is 5-20h, and the ball milling rotating speed is 500-1500 rpm.

TABLE 1 raw material dosage/weight percent

Raw materials

Example 1

Example 2

Example 3

Example 4

Example 5

Example 6

Example 7

Example 8

Si3N4Powder body

83.78％

80.56％

78.23％

75.54％

72.38％

70.26％

68.88％

65.28％

Al2O3Powder body

3.62％

4.05％

4.89％

5.36％

6.62％

7.33％

9.39％

10.77％

AlN powder

9.01％

11.26％

12.63％

13.72％

14.55％

15.49％

17.57％

19.21％

Eu2O3Powder body

3.59％

4.13％

4.25％

5.38％

6.45％

6.92％

4.16％

4.74％

Example 2

The narrow-band emission green nitride fluorescent material was prepared according to the method in example 1, the amounts of the raw materials are shown in table 1, and the specific conditions of the ball milling treatment were as follows: selecting silicon nitride balls and alcohol solution as ball milling media, wherein the mass content of the ball milling media is 30%, the ball milling time is 5h, and the ball milling rotating speed is 600 r/min.

Example 3

The narrow-band emission green nitride fluorescent material was prepared according to the method in example 1, the amounts of the raw materials are shown in table 1, and the specific conditions of the ball milling treatment were as follows: selecting silicon nitride balls and alcohol solution as ball milling media, wherein the mass content of the ball milling media is 40%, the ball milling time is 7h, and the ball milling rotating speed is 800 r/min.

Example 4

The narrow-band emission green nitride fluorescent material was prepared according to the method in example 1, the amounts of the raw materials are shown in table 1, and the specific conditions of the ball milling treatment were as follows: selecting silicon nitride balls and alcohol solution as ball milling media, wherein the mass content of the ball milling media is 50%, the ball milling time is 9h, and the ball milling rotating speed is 900 r/min.

Example 5

The narrow-band emission green nitride fluorescent material was prepared according to the method in example 1, the amounts of the raw materials are shown in table 1, and the specific conditions of the ball milling treatment were as follows: selecting silicon nitride balls and alcohol solution as ball milling media, wherein the mass content of the ball milling media is 60%, the ball milling time is 12h, and the ball milling rotating speed is 1000 r/min.

Example 6

The narrow-band emission green nitride fluorescent material was prepared according to the method in example 1, the amounts of the raw materials are shown in table 1, and the specific conditions of the ball milling treatment were as follows: selecting silicon nitride balls and alcohol solution as ball milling media, wherein the mass content of the ball milling media is 70%, the ball milling time is 15h, and the ball milling rotating speed is 1200 r/min.

Example 7

The narrow-band emission green nitride fluorescent material was prepared according to the method in example 1, the amounts of the raw materials are shown in table 1, and the specific conditions of the ball milling treatment were as follows: selecting silicon nitride balls and alcohol solution as ball milling media, wherein the mass content of the ball milling media is 70%, the ball milling time is 18h, and the ball milling rotating speed is 1400 r/min.

Example 8

The narrow-band emission green nitride fluorescent material was prepared according to the method in example 1, the amounts of the raw materials are shown in table 1, and the specific conditions of the ball milling treatment were as follows: selecting silicon nitride balls and alcohol solution as ball milling media, wherein the mass content of the ball milling media is 70%, the ball milling time is 20h, and the ball milling rotating speed is 1500 r/min.

Comparative example 1

The narrow-band green nitride fluorescent material was prepared according to the method of example 1, and the amounts of the raw materials were the same as those of example 1, except that the sintered product was not subjected to ball milling, and it was found that the high-temperature sintered product had serious particle agglomeration, the particle size was about 15-50 μm, the size was not uniform, and a uniform fluorescent thin film for Micro-LED display could not be prepared. Because the chip spacing in the Micro-LED array is less than 30 micrometers, the particle size of the fluorescent material for Micro-LED display must be Micro-nano scale, and the fluorescent material is prepared into a uniform optical film, otherwise, the light color distribution is not uniform, and the display quality is seriously influenced.

Performance detection

The particle size detection is performed on the products prepared in examples 1 to 8, the result is shown in fig. 1, fig. 1 shows the particle size distribution curve of examples 1 to 8 of the present invention, and it can be seen that a series of nanometer narrow-band green fluorescent materials with uniformly distributed particle sizes and smaller particle sizes can be obtained by optimizing the ball milling process.

The fluorescence detection was performed on the products prepared in examples 1 to 8, and the results are shown in FIG. 2, and FIG. 2 shows the fluorescence spectra of examples 1 to 8 of the present invention. Under the excitation of blue light, the peak position of an emission spectrum is positioned at 540nm, and the half-peak width is narrower at 55 nm. In addition, as the particle size of the phosphor particles decreases, a slight blue shift occurs in the peak position of the emission spectrum, and the half-peak width remains unchanged.

The particle size and fluorescence properties of the products prepared in examples 1-8 are shown in Table 2, where the standard is the median particle size of the ungattled sample (i.e., the sample from example 1 that was removed from the furnace and not ball milled), as can be seen in Table 2: by changing the ball milling process, such as the content of a ball milling medium, the ball milling time and the ball milling rotating speed, a micron-sized sample which is seriously sintered and agglomerated can be ball-milled into a uniform nano-sized sample, and meanwhile, the peak wavelength and the half-peak width of an emission spectrum of the sample are basically kept unchanged, so that the sample has excellent optical performance.

TABLE 2 particle size and fluorescence Properties of the materials

SEM detection is carried out on the product prepared in the example 6, and the result is shown in figure 3, and figure 3 shows the micro-morphology of the product prepared in the example 6 of the invention, and the particle size of the fluorescent particles is nano-scale and is 300 nm.

The preparation product of example 6 was mixed with an organic resin, and a nano-sized narrow band green fluorescent material: the mass ratio of the organic resin is 1: 2, preparing the nano fluorescent film by using the mixture through a scraper method, wherein a substance is shown in fig. 4, and a green fluorescent effect is shown in fig. 4, and the film can be applied to Micro-LED display. FIG. 5 shows a schematic of a nanofluorescent film for a Micro-LED display. The scheme of blue Micro-LED + fluorescent material can be used for realizing high-resolution Micro-LED display, the green nano fluorescent material is prepared into a uniform green fluorescent conversion film to be pasted on the blue Micro-LED, and the green fluorescent film can absorb blue light of the blue LED and convert the blue light into green light with high color purity, so that a green light component with high color purity is provided for Micro-LED display.

The preferred embodiments of the present invention have been described in detail, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. The invention is not described in detail in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.