CN111100639A - Green light emitting fluorescent material - Google Patents

Abstract

The invention provides a green light emitting fluorescent material, the chemical general formula of which is Sr_xBa_yY_zCe_aLu_bAl_cGa_dSi_eO₁₂Wherein x, y, z, a, b, c, d and e are molar coefficients, x is 0-0.5, y is 0.5-1.2, z is 1.6-1.95, a is 0-0.1, b is 0-0.6, c is 2-2.4, d is 1.8-2.0, e is 0.6-1.2, x + y + z + a + b is 3, c + d + e is 5. The fluorescent material can be effectively excited by light of about 450nm and can emit green light with peak wavelength of 513-530 nm; at room temperature, the fluorescence quantum efficiency is 76.81-83.57%; at 150 ℃, the luminous intensity of the fluorescent material can be maintained between 78.64 and 87.12 percent at room temperature, the quantum efficiency is high, and the fluorescent thermal stability is excellent.

Description

Green light emitting fluorescent material

Technical Field

The invention relates to the technical field of luminescent materials, in particular to a green light emitting fluorescent material.

Background

In the past two or more years, phosphor-converted white Light Emitting Diodes (LEDs) have been widely developed by virtue of their excellent properties, such as long life, good reliability and high efficiency, and are widely used in the lighting and display industries. Generally, white LEDs with a high Color Rendering Index (CRI) are more popular because they can more realistically restore the inherent color of an object. It is well known that the most common method of manufacturing a high CRI white LED is to coat green and red emitting phosphors on a blue LED chip with an organic binder. The principle is as follows: when the blue LED is electrified, a part of blue light emitted by the blue LED is absorbed by the fluorescent powder emitting green light and red light and is converted into green light and red light; the other part of the blue light penetrates through the fluorescent powder layer; thus, white light is obtained after the blue light emitted by the blue LED and the green light and the red light emitted by the fluorescent powder are mixed. It follows that a green emitting phosphor plays an essential role in the fabrication of high CRI white LEDs.

At present, researchers have reported many green-emitting phosphors, but there are few white LEDs available for blue pumping, such as (Sr, Ba)₂SiO₄:Eu²⁺，β-SiAlON:Eu²⁺，Y₃(Al,Ga)₅O₁₂:Ce³⁺And Lu₃Al₅O₁₂:Ce³⁺. Although these green phosphors have been commercialized, they all have their own drawbacks. (Sr, Ba)₂SiO₄:Eu²⁺The raw materials are rich and easy to obtain, the emission spectrum is narrow, the quantum efficiency is high, but when the environmental temperature is higher than 125 ℃, the resistance to fluorescence thermal quenching is very poor, and the phase at 150 ℃ is very poorFor brightness value of only about 65% at room temperature β -SiAlON: Eu²⁺The physical and chemical properties are very stable, but the synthesis is difficult, high temperature and high pressure are required, and the quantum efficiency is not high. Lu (Lu)₃Al₅O₁₂:Ce³⁺High quantum efficiency and excellent resistance to fluorescence thermal quenching, but because of its raw material Lu₂O₃Is a very rare earth oxide, and Lu₂O₃The content exceeds 70 wt%, thus resulting in a very expensive price. Y is₃(Al,Ga)₅O₁₂:Ce³⁺The phosphor has high quantum efficiency, but has the greatest disadvantage that the thermal stability of fluorescence is sharply reduced with the increase of gallium content. In view of the current situation, it is very necessary to develop a green light emitting fluorescent material with high quantum efficiency, excellent fluorescence thermal stability, and abundant and readily available raw materials, so as to replace the existing green fluorescent material.

Disclosure of Invention

In view of the above problems in the prior art, an object of the present invention is to provide a fluorescent material that can be efficiently excited by blue light, has high quantum efficiency, and has excellent thermal stability of fluorescence.

In order to achieve the above purpose, the invention provides the following technical scheme:

4. a green light-emitting fluorescent material having a chemical formula: sr_xBa_yY_zCe_aLu_bAl_cGa_dSi_eO₁₂Wherein x, y, z, a, b, c, d and e are molar coefficients, x is 0-0.5, y is 0.5-1.2, z is 1.6-1.95, a is 0-0.1, b is 0-0.6, c is 2-2.4, d is 1.8-2.0, e is 0.6-1.2, x + y + z + a + b is 3, c + d + e is 5.

In a preferred embodiment, x is 0, y is 1.0, z is 1.95, a is 0.05, b is 0, c is 2.0, d is 2.0, and e is 1.0.

Further, the fluorescent material can be effectively excited by light of 410-475nm and can emit green light with the peak wavelength of 513-530 nm; at room temperature, the fluorescence quantum efficiency is 76.81-83.57%; at 150 ℃, the luminous intensity can keep 78.64-87.12% of the luminous intensity at room temperature.

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

the fluorescent material provided by the invention can be effectively excited by light of about 450nm, and has high quantum efficiency and excellent fluorescence thermal stability.

Drawings

FIG. 1 shows a phosphor Sr obtained in example 1_0.5Ba_0.5Y_1.95Ce_0.05Al₂Ga₂S_iO₁₂X-ray diffraction pattern of the powder;

FIG. 2 shows the phosphor Sr obtained in example 1_0.5Ba_0.5Y_1.95Ce_0.05Al₂Ga₂S_iO₁₂An excitation spectrum graph (a), an emission spectrum graph (b), a fluorescence quantum efficiency graph (c) and a relation graph (d) between the emission spectrum and fluorescence intensity and temperature of the powder;

FIG. 3 shows Ba as a phosphor prepared in example 2_0.8Y_1.8Ce_0.1Lu_0.3Al_2.2Ga₂Si_0.8O₁₂X-ray diffraction pattern of the powder;

FIG. 4 shows Ba as a phosphor prepared in example 2_0.8Y_1.8Ce_0.1Lu_0.3Al_2.2Ga₂Si_0.8O₁₂An excitation spectrum graph (a), an emission spectrum graph (b), a fluorescence quantum efficiency graph (c) and a relation graph (d) between the emission spectrum and fluorescence intensity and temperature of the powder;

FIG. 5 shows a fluorescent material BaY obtained in example 3_1.6Ce_0.1Lu_0.3Al_2.2Ga_1.8SiO₁₂X-ray diffraction pattern of the powder;

FIG. 6 shows a fluorescent material BaY obtained in example 3_1.6Ce_0.1Lu_0.3Al_2.2Ga_1.8SiO₁₂An excitation spectrum graph (a), an emission spectrum graph (b), a fluorescence quantum efficiency graph (c) and a relation graph (d) between the emission spectrum and fluorescence intensity and temperature of the powder;

FIG. 7 shows Ba as a phosphor prepared in example 4_0.6Y_1.75Ce_0.05Lu_0.6Al_2.4Ga₂Si_0.6O₁₂X-ray diffraction pattern of the powder;

FIG. 8 shows Ba as a phosphor prepared in example 4_0.6Y_1.75Ce_0.05Lu_0.6Al_2.4Ga₂Si_0.6O₁₂An excitation spectrum graph (a), an emission spectrum graph (b), a fluorescence quantum efficiency graph (c) and a relation graph (d) between the emission spectrum and fluorescence intensity and temperature of the powder;

FIG. 9 shows a fluorescent material BaY obtained in example 5_1.95Ce_0.05Al₂Ga₂SiO₁₂X-ray diffraction pattern of the powder;

FIG. 10 shows a fluorescent material BaY obtained in example 5_1.95Ce_0.05Al₂Ga₂SiO₁₂An excitation spectrum graph (a), an emission spectrum graph (b), a fluorescence quantum efficiency graph (c) and a relation graph (d) between the emission spectrum and fluorescence intensity and temperature of the powder;

FIG. 11 shows Ba as a fluorescent material prepared in example 6_1.2Y_1.65Ce_0.05Lu_0.1Al₂Ga_1.8Si_1.2O₁₂X-ray diffraction pattern of the powder;

FIG. 12 shows Ba as a fluorescent material prepared in example 6_1.2Y_1.65Ce_0.05Lu_0.1Al₂Ga_1.8Si_1.2O₁₂An excitation spectrum graph (a), an emission spectrum graph (b), a fluorescence quantum efficiency graph (c) and a relation graph (d) between the emission spectrum and fluorescence intensity and temperature of the powder;

FIG. 13 shows a phosphor Sr obtained in comparative example 1_0.97Ba_0.98Eu_0.05SiO₄X-ray diffraction pattern of the powder;

FIG. 14 shows a phosphor Sr obtained in accordance with comparative example 1_0.97Ba_0.98Eu_0.05SiO₄An excitation spectrum graph (a), an emission spectrum graph (b), a fluorescence quantum efficiency graph (c) and a relation graph (d) between the emission spectrum and fluorescence intensity and temperature of the powder;

FIG. 15 shows comparative example 2The obtained fluorescent material Y_2.95Ce_0.05Al₂Ga₃O₁₂X-ray diffraction pattern of the powder;

FIG. 16 shows a fluorescent material Y obtained in comparative example 2_2.95Ce_0.05Al₂Ga₃O₁₂The excitation spectrum (a), the emission spectrum (b), the fluorescence quantum efficiency (c) and the relationship graph (d) between the emission spectrum and the fluorescence intensity and the temperature of the powder.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the following examples and comparative examples, the instruments used for the measurement of the relevant properties of the prepared samples were as follows:

1. the crystal structure and phase analysis of the sample are carried out by using a German Bruker D8 advanced X-ray diffractometer with a Cu target K α 1 radiation source

Scanning voltage: 40kV, scanning current: 40mA, scanning angle range: 10-90 °, scanning speed: 10 degree/min;

2. the excitation spectrum and the emission spectrum of the sample are tested by a FluoroSONS-9000 type fluorescence spectrometer produced by Beijing Touhehan light instrument company, the excitation light source is a 450W xenon lamp, and the measurement slit is as follows: 1.0nm, scanning resolution: 1 nm;

3. the data of the change of the emission spectrum and the fluorescence intensity of the sample along with the temperature are tested by adopting a Hangzhou remote photoelectric HASS-2000 high-precision rapid spectrum radiometer, and the internal quantum efficiency of the sample is tested by matching HASS-2000 with an integrating sphere with the diameter of 500 mm.

Example 1

Weighing BaCO₃3.9546g，Y₂O₃8.8570g，Al₂O₃4.0964g，SrCO₃2.9898g，SiO₂2.4118g，CeO₂0.3482g，Ga₂O₃7.5353g, mixing the above raw materials uniformly, grinding to mix the raw materials uniformly, placing the mixed raw materials into a corundum crucible, and placing into a reducing atmosphere (10% by volume of H)₂And 90% of N₂) Composition, the components and content of the reducing atmosphere in the following examples are the same as those of the reducing atmosphere in the examples), heating to 1325 ℃ at a heating rate of 5 ℃/min, preserving heat for 4h, naturally cooling to below 200 ℃ along with the furnace, taking out, sintering to obtain a block product, crushing, screening and grinding the block product to obtain a sample M1.

The obtained sample M1 was analyzed for its crystal structure and phase, XRD was as shown in FIG. 1, and it can be seen from FIG. 1 that the sample M1 obtained in this example was Sr as the main crystal phase_0.5Ba_0.5Y_1.95Ce_0.05Al₂Ga₂S_iO₁₂Has garnet crystal structure and no obvious impurity phase.

The fluorescence property of the prepared sample M1 is tested, the test result is shown in fig. 2, fig. 2 is a fluorescence property spectrum of the sample M1 prepared in this embodiment, and as can be seen from fig. 2(a), the sample M1 prepared in this embodiment can be effectively excited by blue light of about 432 nm; as shown in FIG. 2(b), the sample M1 prepared in this example can emit green light with a peak wavelength of 513nm when excited by 432nm blue light; as can be seen from FIG. 2(c), the fluorescence quantum efficiency of the sample M1 prepared in this example is as high as 76.81% under the excitation of 450nm blue light; as shown in FIG. 2(d), the fluorescence quenching resistance of the sample M1 obtained in this example is excellent, and the emission intensity at 150 ℃ can be maintained at 78.64% at room temperature.

Example 2

Weighing BaCO₃4.1628g，Y₂O₃5.3788g，，Lu₂O₃1.5786g，Al₂O₃2.9645g，SiO₂1.2694g，CeO₂0.4582g，Ga₂O₃4.9574g, mixing the above raw materials, grinding to get the final productThe materials are mixed more uniformly, then the mixture is put into a corundum crucible, and then the corundum crucible is put into a reducing atmosphere box type furnace, the mixture is heated to 1325 ℃ at the heating rate of 5 ℃/min, the temperature is kept for 4h, the mixture is naturally cooled to below 200 ℃ along with the furnace and taken out, and a block product obtained by sintering is crushed, screened and ground to obtain a sample M2.

The obtained sample was subjected to crystal structure and phase analysis, XRD was as shown in FIG. 3, and it can be seen from FIG. 3 that the sample M2 obtained in this example had Ba as the main crystal phase_0.8Y_1.8Ce_0.1Lu_0.3Al_2.2Ga₂Si_0.8O₁₂Having a garnet crystal structure;

the fluorescence property of the prepared sample M2 is tested, the test result is shown in fig. 4, fig. 4 is a fluorescence property spectrum of the sample M2 prepared in this example, and as can be seen from fig. 4(a), the sample M2 prepared in this example can be effectively excited by blue light of about 442 nm; as shown in FIG. 4(b), the sample M2 prepared in this example can emit green light with a peak wavelength of 530nm when excited by 442nm blue light; as can be seen from FIG. 4(c), the sample M2 prepared in this example has a fluorescence quantum efficiency as high as 77.55% under the excitation of 450nm blue light; as shown in FIG. 4(d), the fluorescence quenching resistance of the sample M2 obtained in this example is excellent, and the emission intensity at 150 ℃ can be maintained at 84.01% at room temperature.

Example 3

Weighing BaCO₃5.2034g，Y₂O₃4.7811g，Lu₂O₃1.5786g，Al₂O₃2.9645g，SiO₂1.5867g，CeO₂0.4582g，Ga₂O₃4.4617g, mixing the raw materials uniformly, grinding to mix the raw materials more uniformly, then placing the mixture into a corundum crucible, then placing the corundum crucible into a box type furnace in a reducing atmosphere, heating to 1325 ℃ at a heating rate of 5 ℃/min, preserving heat for 4 hours, naturally cooling to below 200 ℃ along with the furnace, taking out, crushing, screening and grinding the sintered product to obtain a sample M3.

When the crystal structure and phase of the obtained sample M3 were analyzed, XRD was as shown in FIG. 5, and it can be seen from FIG. 5 that the main crystal phase of the sample M3 obtained in this example was BaY_1.6Ce_0.1Lu_0.3Al_2.2Ga_1.8SiO₁₂Has garnet crystal structure and no obvious impurity phase.

The fluorescence property of the prepared sample M3 is tested, the test result is shown in fig. 6, fig. 6 is a fluorescence property spectrum of the sample M3 prepared in this embodiment, and as can be seen from fig. 6(a), the sample M3 prepared in this embodiment can be effectively excited by blue light of about 440 nm; FIG. 6(b) shows that the sample M3 prepared in this example can emit green light with a peak wavelength of 528nm after being excited by 440nm blue light; as can be seen from FIG. 6(c), the fluorescence quantum efficiency of the sample M3 prepared in this example is up to 79.71% under the excitation of 450nm blue light; as is clear from FIG. 6(d), sample M3 obtained in this example is excellent in fluorescence quenching resistance, and its emission intensity at 150 ℃ can be maintained at 85.43% at room temperature.

Example 4

Weighing BaCO₃1.5018g，Y₂O₃2.5154g，Lu₂O₃1.5187g，Al₂O₃1.5556g，SiO₂0.4579g，CeO₂0.1102g，Ga₂O₃2.3846g, uniformly mixing the raw materials, grinding to uniformly mix the raw materials, then putting the mixed raw materials into a corundum crucible, putting the corundum crucible into a box-type furnace in a reducing atmosphere, heating to 1325 ℃ at the heating rate of 5 ℃/min, preserving heat for 4 hours, naturally cooling to below 200 ℃ along with the furnace, taking out, crushing, screening and grinding the sintered product to obtain the sample M4.

When the crystal structure and phase of the obtained sample M4 were analyzed, XRD was as shown in FIG. 7, and it can be seen from FIG. 7 that the main crystal phase of the sample M4 obtained in this example was Ba_0.6Y_1.75Ce_0.05Lu_0.6Al_2.4Ga₂Si_0.6O₁₂Has garnet crystal structure and no obvious impurity phase.

The fluorescence property test of the prepared sample M4 is carried out, the test result is shown in FIG. 8, FIG. 8 is the fluorescence property spectrum of the sample M4 prepared in the embodiment, and as can be seen from FIG. 8(a), the sample M4 prepared in the embodiment can be effectively excited by blue light of about 437 nm; FIG. 8(b) shows that the sample M4 prepared in this example can emit green light with a peak wavelength of 515nm when excited by 437nm blue light; from FIG. 8(c), it can be seen that the fluorescence quantum efficiency of the sample M4 prepared in this example is as high as 76.87% under the excitation of 450nm blue light; FIG. 8(d) shows that the sample M4 obtained in this example has excellent fluorescence quenching resistance, and the emission intensity at 150 ℃ can be maintained at 84.85% at room temperature.

Example 5

Weighing BaCO₃7.6050g，Y₂O₃8.5164g，Al₂O₃3.9390g，SiO₂2.3190g，CeO₂0.3348g，Ga₂O₃7.2456g, uniformly mixing the raw materials, grinding the mixture to enable the raw materials to be uniformly mixed, then putting the mixed raw materials into a corundum crucible, putting the corundum crucible into a reduction atmosphere box type furnace, heating the corundum crucible to 1325 ℃ at the heating rate of 5 ℃/min, preserving heat for 4 hours, naturally cooling the corundum crucible to below 200 ℃ along with the furnace, taking out the corundum crucible, sintering the corundum crucible to obtain a block product, crushing and screening the block product, and grinding the block product to obtain the sample M5.

The obtained sample M5 was subjected to crystal structure and phase analysis, and XRD was as shown in FIG. 9; as can be seen from FIG. 9, sample M5 obtained in this example had a BaY main crystal phase_1.95Ce_0.05Al₂Ga₂SiO₁₂Has garnet crystal structure and no obvious impurity phase.

The fluorescence property of the sample M5 was measured, and the results are shown in FIG. 10, in which FIG. 10 shows BaY obtained in this example_1.95Ce_0.05Al₂Ga₂SiO₁₂(ii) a fluorescence spectrum of; as can be seen from fig. 10(a), the sample M5 prepared in this example can be effectively excited by blue light around 430 nm; FIG. 10(b) shows that the sample M5 prepared in this example can emit green light with a peak wavelength of 518nm when excited by 430nm blue light; as can be seen from FIG. 10(c), the fluorescence quantum efficiency of the sample M5 prepared in this example is as high as 83.57% under the excitation of 450nm blue light; FIG. 10(d) shows that the sample M5 obtained in this example has excellent fluorescence quenching resistance, and the emission intensity at 150 ℃ can be maintained at 87.12% at room temperature.

Example 6:

weighing BaCO₃3.0035g，Y₂O₃2.3717g，Al₂O₃1.2963g，Lu₂O₃0.2531g，SiO₂0.9159g，CeO₂0.1102g，Ga₂O₃2.1461g, mixing the raw materials uniformly, grinding to mix the raw materials more uniformly, then placing the mixture into a corundum crucible, placing the corundum crucible into a reduction atmosphere box furnace, heating to 1325 ℃ at the heating rate of 5 ℃/min, keeping the temperature for 4h, naturally cooling to below 200 ℃ along with the furnace, taking out, sintering to obtain a block product, crushing, screening and grinding the block product to obtain the sample M6. Ba_1.2Y_1.65Ce_0.05Lu_0.1Al₂Ga_1.8Si_1.2O₁₂And (3) powder.

When the crystal structure and phase of the obtained sample M6 were analyzed, XRD was as shown in FIG. 11, and it can be seen from FIG. 11 that the main crystal phase of the sample M6 obtained in this example was Ba_1.2Y_1.65Ce_0.05Lu_0.1Al₂Ga_1.8Si_1.2O₁₂Has garnet crystal structure and no obvious impurity phase.

The fluorescence property of the prepared sample M6 is tested, and the test result is shown in FIG. 12, where FIG. 12 is the fluorescence property spectrum of the sample M6 prepared in this example; as can be seen from fig. 12(a), the sample M6 prepared in this example can be effectively excited by blue light around 430 nm; FIG. 12(b) shows that the sample M6 prepared in this example can emit green light with a peak wavelength of 518nm when excited by 430nm blue light; as can be seen from FIG. 12(c), the fluorescence quantum efficiency of the sample M6 prepared in this example is up to 81.01% under the excitation of 450nm blue light; FIG. 12(d) shows that the sample M6 obtained in this example has excellent fluorescence quenching resistance, and the emission intensity at 150 ℃ can be maintained at 86.96% at room temperature.

Comparative example 1

Weighing SrCO₃3.5541g，BaCO₃4.7494g，Eu₂O₃0.2167g，SiO₂1.4778g, mixing the above raw materials uniformly, grinding to mix the raw materials uniformly, placing the mixed raw materials into a corundum crucible, and placing into a reduction atmosphere box furnace (10% by volume of H)₂And 90% of N₂) The components and the contents of the reducing atmosphere in the following examples are the same as those of the reducing atmosphere in the comparative example), then the sample is heated to 1275 ℃ at the heating rate of 5 ℃/min, the temperature is kept for 4h, the sample is taken out after being naturally cooled to below 200 ℃ along with the furnace, and the product obtained after sintering is crushed, screened and ground to obtain a sample N1.

The crystal structure and phase analysis were performed on the obtained sample N1, XRD was as shown in FIG. 13, and it can be seen from FIG. 13 that the main crystal phase of sample N1 obtained in this comparative example was Sr_0.97Ba_0.98Eu_0.05SiO₄。

The fluorescence property of the sample N1 is tested, the test result is shown in FIG. 14, and FIG. 14 is the fluorescence property spectrum of the sample N1 prepared by the comparative example; from FIG. 14(a), it can be seen that the sample N1 prepared in this comparative example can be efficiently excited by blue light around 430 nm; FIG. 14(b) shows that sample N1, excited by 430nm blue light, emits green light with a peak wavelength of 525 nm; from FIG. 14(c), it can be seen that the fluorescence quantum efficiency of sample N1 prepared in this comparative example is 71.71% under the excitation of 450nm blue light; as can be seen from FIG. 14(d), the emission intensity of the sample N1 obtained in this comparative example can be maintained at 75.25% at room temperature at 150 ℃.

Comparative example 2

Weighing Y₂O₃4.5950g，CeO₂0.1194g，Al₂O₃1.4048g，Ga₂O₃3.8762g, mixing the raw materials uniformly, grinding to mix the raw materials more uniformly, then placing the mixture into a corundum crucible, placing the corundum crucible into a reduction atmosphere box furnace, heating to 1450 ℃ at a heating rate of 5 ℃/min, keeping the temperature for 4h, naturally cooling to below 200 ℃ along with the furnace, taking out, sintering to obtain a block product, crushing, screening and grinding the block product to obtain a sample N2.

The crystal structure and phase analysis were performed on the obtained sample N2, XRD was as shown in FIG. 15, and it can be seen from FIG. 15 that the main crystal phase of sample N2 obtained in this comparative example was Y_2.95Ce_0.05Al₂Ga₃O₁₂Has garnet crystal structure and no obvious impurity phase.

The fluorescence property of the prepared sample N2 is tested, the test result is shown in FIG. 16, and FIG. 16 is the fluorescence property spectrum of the sample N2 prepared by the comparative example; from FIG. 16(a), it is understood that the sample N2 obtained in this example is efficiently excited by blue light around 437 nm; as shown in FIG. 16(b), the sample N2 can emit green light with a peak wavelength of 525nm after being excited by 437nm blue light; from FIG. 16(c), it can be seen that the fluorescence quantum efficiency of sample N2 prepared in this comparative example is 75.61% under the excitation of 450nm blue light; as can be seen from FIG. 16(d), the emission intensity of the sample N2 obtained in this comparative example can be maintained at 62.67% at room temperature at 150 ℃.

It should be noted that the samples of comparative example 1 and comparative example 2 are respectively matched with the commercial silicate green light emitting fluorescent material (Sr, Ba) which is currently the mainstream on the market₂SiO₄:Eu²⁺And aluminate green light emitting phosphor Y₃Al₂Ga₃O₁₂:Ce³⁺Have very close chemical compositions.

As can be seen from the test results of examples 1-6 and comparative examples 1-2, the fluorescent material provided by the present invention has higher fluorescence quantum efficiency (as low as 76.81% and as high as 83.57% compared to the conventional fluorescent material, which is currently (Sr, Ba)₂SiO₄:Eu²⁺The quantum efficiency of the material is 71.71%, the prior Y₃Al₂Ga₃O₁₂:Ce³⁺The quantum efficiency of the material is 75.61 percent), the fluorescence thermal stability is excellent (at 150 ℃, the lowest luminescence property still maintains 78.64 percent at room temperature, and the highest luminescence property still maintains 87.12 percent at room temperature), compared with the prior (Sr, Ba)₂SiO₄:Eu²⁺Retention of material 75.25%, conventional Y₃Al₂Ga₃O₁₂:Ce³⁺Retention of material 62.67%); in addition, from the test results of the samples in the examples, it can be seen that when the chemical formula of the fluorescent material is BaY_1.95Ce_0.05Al₂Ga₂SiO₁₂In the meantime, the fluorescence quantum efficiency and the anti-fluorescence thermal quenching performance are optimal, the fluorescence quantum efficiency is as high as 83.57%, and the fluorescence intensity at 150 ℃ can still keep 87.12% of that at room temperature, so that example 5 is the optimal embodiment of the invention.

While the present invention has been described with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (3)

1. A green light-emitting fluorescent material characterized by having a chemical formula: sr_xBa_yY_zCe_aLu_bAl_cGa_dSi_eO₁₂Wherein x, y, z, a, b, c, d and e are molar coefficients, x is 0-0.5, y is 0.5-1.2, z is 1.6-1.95, a is 0-0.1, b is 0-0.6, c is 2-2.4, d is 1.8-2.0, e is 0.6-1.2, x + y + z + a + b is 3, c + d + e is 5.

2. The green-emitting phosphor of claim 1, wherein x is 0, y is 1.0, z is 1.95, a is 0.05, b is 0, c is 2.0, d is 2.0, and e is 1.0.

3. The green light-emitting fluorescent material as claimed in claim 1, wherein the fluorescent material can be effectively excited by light of 410-475nm and can emit green light with a peak wavelength of 513-530 nm; at room temperature, the fluorescence quantum efficiency is 76.81-83.57%; at 150 ℃, the luminous intensity can keep 78.64-87.12% of the luminous intensity at room temperature.

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