CN109370588B - Nitride phosphor powder for semiconductor light emitting, its preparation method and light emitting device - Google Patents

Abstract

The invention belongs to the technical field of luminescent materials, and particularly relates to a semiconductor luminescent materialThe nitride fluorescent powder, a preparation method thereof and a light-emitting device. The chemical general formula of the nitride fluorescent powder is A_{3‑x‑y‑z}M_xD₆(N_11‑xC_x) (yCe, zR); wherein, A is selected from at least one of La, Y, Lu and Gd, M is selected from at least one of Ca, Sr and Ba, D is selected from at least one of Si, Ge, Ti, Se and Hf, R is selected from at least one of Pr, Tb, Nd and Dy, and x is more than or equal to 0.001 and less than or equal to 2, Y is more than or equal to 0.005 and less than or equal to 0.2, and z is more than or equal to 0.001 and less than or equal to 0.1. The nitride fluorescent powder has high luminous efficiency and good thermal stability, and is very suitable for being applied to high-power LED devices.

Description

Nitride phosphor powder for semiconductor light emitting, its preparation method and light emitting device

technical field

The invention belongs to the technical field of light-emitting materials, and in particular relates to a nitride fluorescent powder for semiconductor light-emitting, a preparation method thereof, and a light-emitting device.

Background technique

High-power light-emitting diodes (Light Emitting Diode, LED) have excellent characteristics such as small size, long life, high electro-optical conversion efficiency, fast response, energy saving, and environmental protection, and are widely used in commercial lighting, street lights, car lights, searchlights and other fields. In recent years, white LEDs have been widely popularized in the field of low-power lighting, and both technology and application fields have reached a relatively mature stage. However, in the field of high-power technology and application, it is still in its infancy and development stage. The main reason is that under high-energy excitation, high thermal radiation and strong ray radiation cause great irreversible damage to the phosphor, which reduces the service life and stability of the device. sex and light effects. Therefore, the development of LED phosphors with high energy density resistance is the key to realize high light efficiency, high stability and high power LED devices.

La ₃ Si ₆ N ₁₁ : Ce ³⁺ phosphor has obvious advantages in high-power LED applications because of its high thermal stability. However, due to the relatively harsh preparation conditions, and the thermal stability and external quantum efficiency still need to be further improved, it has not yet been widely used in high-power LEDs. Therefore, it is very important to develop nitride phosphors with simple preparation method, high thermal stability and high external quantum efficiency that can be applied to high-power LED devices.

Contents of the invention

The purpose of the present invention is to overcome the above-mentioned deficiencies of the prior art, to provide a nitride phosphor powder for semiconductor light-emitting and its preparation method and a light-emitting device, aiming to solve the low light efficiency and poor resistance to high energy density of the existing phosphor powder technology question.

For realizing above-mentioned purpose of the invention, the technical scheme that the present invention adopts is as follows:

One aspect of the present invention provides a nitride phosphor, the general chemical formula of the nitride phosphor is A _{3-xy- z} M _x D ₆ (N _11-x C _x ):(yCe,zR); wherein, A is selected from at least one of La, Y, Lu and Gd, M is selected from at least one of Ca, Sr and Ba, D is selected from at least one of Si, Ge, Ti, Se and Hf, and R is selected from At least one of Pr, Tb, Nd and Dy, and 0.001≤x≤2, 0.005≤y≤0.2, 0.001≤z≤0.1.

In the nitride phosphor powder provided by the present invention, A ³⁺ and N ^3- are replaced by an appropriate amount of M ²⁺ and C ^4- ions, respectively, thereby improving the lattice stability and crystal field environment around the luminescent center of the phosphor powder, making the fluorescence The light color performance of the powder is controllable and adjustable, and the thermal stability is greatly improved; at the same time, the introduction of R ³⁺ into the nitride phosphor powder of the present invention further improves the luminous efficiency of the phosphor powder (external quantum efficiency ), finally, based on the synergistic effect of each element in the general chemical formula, the nitride phosphor has higher luminous efficiency and better thermal stability, and is very suitable for application in high-power LED devices.

Another aspect of the present invention provides a method for preparing the above-mentioned nitride phosphor, comprising the following steps:

Mixing the nitride of the first A, the nitride of the first D and CeN, under the reduction of _N2 and _H2 , performing the first sintering treatment to obtain the intermediate;

Add the second nitride of A, the second carbide of D, the nitride of M and the nitride or fluoride of R into the intermediate, and carry out the second sintering treatment under the reducing atmosphere of C to obtain the nitrogen Compound phosphor;

Wherein, the total molar weight of A of the nitride of the first A and the nitride of the second A, and the total molar weight of D of the nitride of the first D and the nitride of the second D are respectively The molar amounts of A and D in the general chemical formula of the nitride phosphor.

The nitride phosphor powder provided by the present invention is prepared by a two-step method. The preparation method is simple in process and low in cost. First, the nitride of the first A, the nitride of the first D and CeN are mixed to form an intermediate, and then the intermediate It is mixed with the nitride of the second A, the carbide of the second D, the nitride of M and the nitride or fluoride of R to make the final nitride phosphor, so that the nitride phosphor made in two steps is not only High light efficiency, good thermal stability, and better crystallization effect.

Finally, the present invention provides a light-emitting device, including an excitation light source and a fluorescent substance excited by the excitation light source, and the fluorescent substance is the nitride phosphor powder described in the present invention or the nitride phosphor obtained by the preparation method described in the present invention Phosphor.

In the light-emitting device of the present invention, the fluorescent substance excited by the excitation light source is the unique nitride phosphor powder of the present invention. The nitride has high light efficiency and good thermal stability, and finally improves the light efficiency and stability of the light-emitting device. .

Description of drawings

Fig. 1 is the excitation spectrogram (detection wavelength 540nm) of the embodiment of the present invention 40;

Fig. 2 is the emission spectrogram (excitation wavelength 450nm) of embodiment 40 of the present invention

Fig. 3 (a) is the scanning electron micrograph of the nitride phosphor obtained by the two-step method of Example 40 of the present invention;

Fig. 3 (b) is the scanning electron micrograph of the nitride phosphor obtained by the one-step method of Example 44 of the present invention;

Fig. 4 is a thermal stability comparison chart of Example 40 of the present invention and Comparative Example 1.

Detailed ways

In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention will be further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

The terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features.

On the one hand, the embodiment of the present invention provides a nitride phosphor, the general chemical formula of the nitride phosphor is A _3-xyz M _x D ₆ (N _11-x C _x ):(yCe,zR); Among them, A is selected from at least one of La (lanthanum), Y (yttrium), Lu (lutetium) and Gd (gadolinium), and M is selected from at least one of Ca (calcium), Sr (strontium) and Ba (barium). One, D is selected from at least one of Si (silicon), Ge (germanium), Ti (titanium), Se (selenium) and Hf (hafnium), R is selected from Pr (praseodymium), Tb (terbium), Nd (neodymium) and Dy (dysprosium), and 0.001≤x≤2, 0.005≤y≤0.2, 0.001≤z≤0.1.

In the nitride phosphor powder provided by the embodiment of the present invention, A ³⁺ and N ^3- are replaced by an appropriate amount of M ²⁺ and C ^4- ions, respectively, thereby improving the lattice stability and crystal field environment around the luminescent center of the phosphor, The light color performance of the phosphor is controllable and adjustable, and the thermal stability is greatly improved; at the same time, the introduction of R ³⁺ into the nitride phosphor of the present invention further improves the luminous efficiency of the phosphor through the energy transfer method (external Quantum efficiency), finally, based on the synergistic effect of each element in the general chemical formula, the nitride phosphor has high light efficiency and good thermal stability, and is very suitable for high-power LED devices.

Further, in the general chemical formula of the nitride phosphor, M is Ca, this is because the Ca ²⁺ radius is smaller than the La ³⁺ radius, and the C ^4- ion radius is greater than the N ^3- radius, when Ca-C simultaneously replaces La -N element, the stability of its crystal structure will be higher, the field emission of the crystal around the luminescent center will change, the light color performance is easy to control, and the thermal stability is greatly improved; further, A is La and/or Lu, first when When A is La or Lu, the phase purity of the prepared phosphor is higher, and its luminous efficiency is higher; when an appropriate amount of Lu replaces La element, that is, when both La and Lu are contained, the phosphor has better crystallization performance and higher luminous efficiency. The density is enhanced and the stability is improved; furthermore, R is Pr and/or Tb, and when Pr and/or Tb is selected, energy transfer will occur, and the luminous efficiency of the phosphor will be further improved.

Further, in the general chemical formula of the nitride phosphor, D is selected from at least one of Si, Ge, Ti, and Se, and D includes Si. That is, D must contain Si, preferably, D is Si and Ge, or D is Si and Se. Assuming that the molar percentage of D is 100%, the molar content of Si is 80-90%. When the molar content of Si is 100%, that is, when D is only Si, the nitride phosphor has better luminous intensity; but when the Si content is too high, the substitution amount of Se or Ge is too small, which is not conducive to the morphology of the phosphor With the improvement of crystallization properties, the light color performance of the phosphor powder is not significantly improved. Therefore, in order to improve the overall performance of the phosphor powder, it is necessary to appropriately reduce the molar content of Si. However, when the Si content is too low, the structure of the phosphor powder will be distorted, and the luminous efficiency And the stability will decrease; therefore, the molar content of Si is selected to be between 80-90%, so that the phosphor not only improves the light color performance but also improves the luminous efficiency.

Further, in the general chemical formula of the nitride phosphor, in the general chemical formula of the nitride phosphor, A is La and Lu, and the molar ratio of La and Lu is (4-10):1. By adjusting the ratio of La and Lu, the stability of the phosphor lattice can be better improved. The thermal stability of the nitride phosphor composed of A in this ratio range is the best; when the La/Lu ratio is too low, the phosphor structure changes, the luminous efficiency of the phosphor will decrease. When the La/Lu ratio is too high, the crystallization and structural stability of the phosphor will not be significantly improved, and the light and color performance will not be significantly improved. Therefore, the molar ratio of La to Lu is between (4-10) : In the range of 1, the phosphor not only improves the light color performance but also improves the luminous efficiency.

Further, in the general chemical formula of the nitride phosphor, 0.01≤x≤1.5, 0.01≤y≤0.1, 0.005≤z≤0.05; when the x value is too high, the phase purity of the phosphor decreases, and the luminous efficiency and stability When the value of x is too low, the change of phosphor microstructure is not obvious enough, the control of light color performance is not obvious, and the improvement effect of its luminous efficiency and thermal stability is small, so the effect in the range of 0.01≤x≤1.5 is the best. Excellent; when the y value is too high, there will be non-radiative energy transfer between Ce ³⁺ and Ce ³⁺ , which will lead to a decrease in the luminous efficiency and stability of the phosphor. When the y value is too low, the concentration of luminescent centers in the phosphor will Too low, the luminous efficiency is relatively low, so the effect is optimal in the range of 0.01≤y≤0.1; in addition, a large z value will lead to non-radiative energy transfer between activators, concentration quenching, and more absorption of blue light , will lead to a decrease in Ce ³⁺ emission intensity, and a small z value, the effect of energy transfer from R ions to Ce ions is not obvious, and the luminous efficiency is not significantly improved, so the effect is best in the range of 0.005≤z≤0.05.

On the other hand, the embodiment of the present invention also provides a method for preparing the above-mentioned nitride phosphor, comprising the following steps:

S01: Mix the nitride of the first A, the nitride of the first D and CeN, and perform the first sintering treatment under the reduction of _N2 and _H2 to obtain an intermediate;

S02: Add the second nitride of A, the second carbide of D, the nitride of M and the nitride or fluoride of R into the intermediate, and carry out the second sintering treatment under the reducing atmosphere of C to obtain the obtained The nitride phosphor powder;

Wherein, the total molar weight of A of the nitride of the first A and the nitride of the second A, and the total molar weight of D of the nitride of the first D and the nitride of the second D are respectively The molar amounts of A and D in the general chemical formula of the nitride phosphor.

The preparation method of the nitride phosphor provided by the embodiment of the present invention is simple in process and low in cost. The nitride of the second A; the nitride of the raw material D is divided into two parts: the nitride of the first D and the nitride of the second D; then the nitride of the first A, the nitride of the first D and CeN are mixed to make Intermediate, and then mix the intermediate with the second A nitride, the second D carbide, M nitride and R nitride or fluoride to make the final nitride phosphor, which is made in two steps The nitride phosphor not only has higher light efficiency and better thermal stability, but also has better crystallization effect.

Further, in the above step S01, the sum of the molar weights of the A element in the nitride of the first A and the Ce element in the CeN and the molar weight of the D element in the first D nitride The ratio is 1:3. Within this ratio range, intermediates can be better produced, which is beneficial to the subsequent production of nitride phosphors.

Furthermore, the temperature of the first sintering treatment is 1300-1500°C, and the time is 5-7h; the temperature of the second sintering treatment is 1500-1700°C, and the time is 7-9h. Within the above range of temperature and time, the intermediate and the final nitride phosphor can be better sintered.

In a specific embodiment, the preparation method of the nitride phosphor comprises:

(1) Mix a certain proportion of nitrides of A, nitrides of D and CeN powder uniformly according to a certain stoichiometric ratio, and put them into a tungsten crucible, and keep it at 1400°C under the reduction of N ₂ /H ₂ mixed gas 6h sintering, after crushing to obtain an intermediate; wherein A is any one or more of La, Y, Lu, Gd, and D is any one or more of Si, Ge, Ti, Se, Hf;

(2) Add nitrides of A, nitrides of M, carbides of D, and nitrides or fluorides of R to the obtained intermediate, mix according to a certain ratio, and sinter at 1600°C for 8 hours in a reducing atmosphere of C , crushing, washing and drying the obtained fluorescent substance to finally obtain the target nitride phosphor.

Finally, an embodiment of the present invention provides a light-emitting device, including an excitation light source and a fluorescent substance excited by the excitation light source. The fluorescent substance is the nitride phosphor powder described in the embodiment of the present invention or the phosphor powder described in the embodiment of the present invention. The nitride phosphor powder obtained by the preparation method.

In the light-emitting device of the embodiment of the present invention, the fluorescent substance excited by the excitation light source is the unique nitride phosphor powder of the embodiment of the present invention. The nitride phosphor has high light efficiency and good thermal stability, and finally improves the light emission of the light-emitting device. efficiency and stability.

Further, the excitation light source is a semiconductor chip with an emission wavelength range of 330-480 nm.

The present invention has been tested many times successively, and a part of the test results are given as a reference to further describe the invention in detail, and will be described in detail below in conjunction with specific examples.

Example 1

A high-power nitride fluorescent material with a chemical formula of La _2.445 Ba _0.5 Si ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride fluorescent material comprises the following steps: uniformly mixing a certain proportion of LaN, Si ₃ N ₄ and CeN according to a certain molar ratio, putting them into a tungsten crucible, and reducing the N ₂ /H ₂ mixed gas sintering at 1400°C for 6 hours, and the intermediate was obtained after crushing; then the obtained intermediate was uniformly mixed with LaN, Ba ₃ N ₂ , Si ₃ N ₄ , TbN, and SiC according to a certain molar ratio, and the intermediate was mixed in a reducing atmosphere of C sintering at 1600° C. for 8 hours, crushing, washing and drying the obtained fluorescent substance to finally obtain La _2.445 Ba _0.5 Si ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb) phosphor. The fluorescence emission characteristics of the obtained phosphor powder are shown in Table 1.

Example 2

A high-power nitride fluorescent material with a chemical formula of La _2.445 Sr _0.5 Si ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride fluorescent material comprises the following steps: uniformly mixing a certain proportion of LaN, Si ₃ N ₄ and CeN according to a certain molar ratio, putting them into a tungsten crucible, and reducing the N ₂ /H ₂ mixed gas sintering at 1400°C for 6 hours, and the intermediate was obtained after crushing; then the obtained intermediate was uniformly mixed with LaN, Sr ₃ N ₂ , Si ₃ N ₄ , TbN, and SiC in a certain molar ratio, and the intermediate was mixed in a reducing atmosphere of C sintering at 1600°C for 8 hours, crushing, washing and drying the obtained fluorescent material to finally obtain La _2.445 Sr _0.5 Si ₆ N _10.5 C _0.5 :(0.05Ce, 0.005Tb) fluorescent powder. The fluorescence emission characteristics of the obtained phosphor powder are shown in Table 1.

Example 3

A high-power nitride fluorescent material with a chemical formula of La _2.445 Ca _0.5 Si ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material comprises the following steps: uniformly mixing a certain proportion of LaN, Si ₃ N ₄ and CeN according to a certain molar ratio, putting them into a tungsten crucible, and mixing them in a N ₂ /H ₂ mixed gas Under the reduction of 1400°C for 6 hours, the intermediate was obtained after crushing; then the obtained intermediate was uniformly mixed with LaN, Ca ₃ N ₂ , Si ₃ N ₄ , TbN, and SiC according to a certain molar ratio, and heated at C Under reducing atmosphere, sintering at 1600°C for 8 hours, crushing, washing, and drying the obtained fluorescent substance to finally obtain La _2.445 Ca _0.5 Si ₆ N _10.5 C _0.5 :(0.05Ce, 0.005Tb) phosphor. The fluorescence emission characteristics of the obtained phosphor powder are shown in Table 1.

Example 4

A high-power nitride fluorescent material with a chemical formula of Y _2.445 Ca _0.5 Si ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material includes the following steps: uniformly mix a certain proportion of YN, Si ₃ N ₄ and CeN according to a certain molar ratio, put them into a tungsten crucible, and mix them in a N ₂ /H ₂ mixed gas Under the reduction of 1400°C for 6 hours, the intermediate was obtained after crushing; then the obtained intermediate was uniformly mixed with YN, Ca ₃ N ₂ , Si ₃ N ₄ , TbN, and SiC according to a certain molar ratio, and heated at C Under reducing atmosphere, heat preservation at 1600° C. for 8 hours for sintering, crush, wash and dry the obtained fluorescent substance to finally obtain Y _2.445 Ca _0.5 Si ₆ N _10.5 C _0.5 :(0.05Ce, 0.005Tb) phosphor. The fluorescence emission characteristics of the obtained phosphor powder are shown in Table 1.

Example 5

A high-power nitride fluorescent material with a chemical formula of Lu _2.445 Ca _0.5 Si ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material comprises the following steps: uniformly mixing a certain proportion of LuN, Si ₃ N ₄ and CeN according to a certain molar ratio, putting them into a tungsten crucible, and mixing them in a N ₂ /H ₂ mixed gas Under the reduction of 1400°C for 6 hours, the intermediate was obtained after crushing; then the obtained intermediate was uniformly mixed with LuN, Ca ₃ N ₂ , Si ₃ N ₄ , TbN, and SiC according to a certain molar ratio, and heated at C Under a reducing atmosphere, heat preservation at 1600°C for 8 hours for sintering, crushing, washing and drying the obtained fluorescent substance to finally obtain Lu _2.445 Ca _0.5 Si ₆ N _10.5 C _0.5 :(0.05Ce, 0.005Tb) fluorescent powder. The fluorescence emission characteristics of the obtained phosphor powder are shown in Table 1.

Example 6

A high-power nitride fluorescent material with a chemical formula of Gd _2.445 Ca _0.5 Si ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material comprises the following steps: uniformly mixing a certain proportion of GdN, Si ₃ N ₄ and CeN according to a certain molar ratio, putting them into a tungsten crucible, and mixing them in a N ₂ /H ₂ mixed gas Under the reduction of 1400°C for 6 hours, the intermediate was obtained after crushing; then the obtained intermediate was uniformly mixed with GdN, Ca ₃ N ₂ , Si ₃ N ₄ , TbN, and SiC according to a certain molar ratio, and heated at C Under reducing atmosphere, heat preservation at 1600°C for 8 hours for sintering, crush, wash and dry the obtained fluorescent substance to finally obtain Gd _2.445 Ca _0.5 Si ₆ N _10.5 C _0.5 :(0.05Ce, 0.005Tb) fluorescent powder. The fluorescence emission characteristics of the obtained phosphor powder are shown in Table 1.

Example 7

A high-power nitride fluorescent material with a chemical formula of La _2.445 Ca _0.5 Ge ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material comprises the following steps: uniformly mixing a certain proportion of LaN, Ge ₃ N ₄ and CeN according to a certain molar ratio, putting them into a tungsten crucible, and mixing them in a N ₂ /H ₂ mixed gas Under the reduction of 1400°C for 6 hours, the intermediate was obtained after crushing; then the obtained intermediate was uniformly mixed with LaN, Ca ₃ N ₂ , Ge ₃ N ₄ , TbN, and SiC according to a certain molar ratio, and heated at C Under reducing atmosphere, sintering at 1600°C for 8 hours, crushing, washing, and drying the obtained fluorescent substance to finally obtain La _2.445 Ca _0.5 Ge ₆ N _10.5 C _0.5 :(0.05Ce, 0.005Tb) phosphor. The fluorescence emission characteristics of the obtained phosphor powder are shown in Table 1.

Example 8

A high-power nitride fluorescent material with a chemical formula of La _2.445 Ca _0.5 Ti ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 9

A high-power nitride fluorescent material with a chemical formula of La _2.445 Ca _0.5 Se ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 10

A high-power nitride fluorescent material with a chemical formula of La _2.445 Ca _0.5 Hf ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 11

A high-power nitride fluorescent material with a chemical formula of La _1.956 Lu _0.489 Ca _0.5 Si ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 12

A high-power nitride fluorescent material with a chemical formula of La _2.2005 Lu _0.2445 Ca _0.5 Si ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 13

A high-power nitride fluorescent material with a chemical formula of La _2.145 Lu _0.3 Ca _0.5 Si ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 14

A high-power nitride fluorescent material with a chemical formula of La _1.845 Lu _0.6 Ca _0.5 Si ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 15

A high-power nitride fluorescent material with a chemical formula of La _2.345 Lu _0.1 Ca _0.5 Si ₆ N _10.5 C _0.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 16

A high-power nitride fluorescent material with a chemical formula of La _2.935 Ca _0.01 Si ₆ N _10.99 C _0.01 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 17

A high-power nitride fluorescent material with a chemical formula of La _2.845 Ca _0.1 Si ₆ N _10.9 C _0.1 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 18

A high-power nitride fluorescent material with a chemical formula of La _2.645 Ca _0.3 Si ₆ N _10.7 C _0.3 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 19

A high-power nitride fluorescent material with a chemical formula of La _2.145 Ca _0.8 Si ₆ N _10.2 C _0.8 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 20

A high-power nitride fluorescent material, the chemical formula is La _1.945 CaSi ₆ N ₁₀ C: (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 21

A high-power nitride fluorescent material with a chemical formula of La _1.445 Ca _1.5 Si ₆ N _9.5 C _1.5 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 22

A high-power nitride fluorescent material, the chemical formula is LaCa ₂ Si ₆ N ₉ C ₂ : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 23

A high-power nitride fluorescent material with a chemical formula of La _1.9305 Y _0.2145 Ca _0.8 Si ₆ N _10.2 C _0.8 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 24

A high-power nitride fluorescent material with a chemical formula of La _1.9305 Gd _0.2145 Ca _0.8 Si ₆ N _10.2 C _0.8 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 25

A high-power nitride fluorescent material with a chemical formula of La _1.9305 Lu _0.2145 Ca _0.8 Si ₆ N _10.2 C _0.8 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 26

A high-power nitride fluorescent material with a chemical formula of La _1.9305 Lu _0.2145 Ca _0.8 Si ₅ GeN _10.2 C _0.8 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 27

A high-power nitride fluorescent material with a chemical formula of La _1.9305 Lu _0.2145 Ca _0.8 Si ₅ SeN _10.2 C _0.8 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 28

A high-power nitride fluorescent material with a chemical formula of La _1.9305 Lu _0.2145 Ca _0.8 Si ₅ TiN _10.2 C _0.8 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 29

A high-power nitride fluorescent material with a chemical formula of La _1.9305 Lu _0.2145 Ca _0.8 Si ₅ HfN _10.2 C _0.8 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 30

A high-power nitride fluorescent material with a chemical formula of La _1.9305 Lu _0.2145 Ca _0.8 Si _4.8 Se _1.2 N _10.2 C _0.8 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 31

A high-power nitride fluorescent material with a chemical formula of La _1.9305 Lu _0.2145 Ca _0.8 Si _4.5 Se _1.5 N _10.2 C _0.8 : (0.05Ce, 0.005Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 32

A high-power nitride fluorescent material with a chemical formula of La _1.9795 Lu _0.2145 Ca _0.8 Si ₅ SeN _10.2 C _0.8 : (0.005Ce, 0.001Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 33

A high-power nitride fluorescent material with a chemical formula of La _1.9545 Lu _0.2145 Ca _0.8 Si ₅ SeN _10.2 C _0.8 : (0.03Ce, 0.001Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 34

A high-power nitride fluorescent material with a chemical formula of La _1.9045 Lu _0.2145 Ca _0.8 Si ₅ SeN _10.2 C _0.8 : (0.08Ce, 0.001Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 35

A high-power nitride fluorescent material with a chemical formula of La _1.8845 Lu _0.2145 Ca _0.8 Si ₅ SeN _10.2 C _0.8 : (0.1Ce, 0.001Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 36

A high-power nitride fluorescent material with a chemical formula of La _1.8345 Lu _0.2145 Ca _0.8 Si ₅ SeN _10.2 C _0.8 : (0.15Ce, 0.001Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 37

A high-power nitride fluorescent material with a chemical formula of La _1.7845 Lu _0.2145 Ca _0.8 Si ₅ SeN _10.2 C _0.8 : (0.2Ce, 0.001Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 38

A high-power nitride fluorescent material, the chemical formula is La _1.9345 Lu _0.2145 Ca _0.8 Si ₅ GeN _10.2 C _0.8 : (0.05Ce, 0.001Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 39

A high-power nitride fluorescent material with a chemical formula of La _1.9255 Lu _0.2145 Ca _0.8 Si ₅ GeN _10.2 C _0.8 : (0.05Ce, 0.01Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 40

A high-power nitride fluorescent material with a chemical formula of La _1.9055 Lu _0.2145 Ca _0.8 Si ₅ GeN _10.2 C _0.8 : (0.05Ce, 0.03Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescence emission characteristics of the obtained phosphor powder are shown in Table 1, the excitation spectrum is as shown in Figure 1, and the emission spectrum is as shown in Figure 2. The scanning electron microscope image of the phosphor powder is shown in Figure 3(a).

Example 41

A high-power nitride fluorescent material with a chemical formula of La _1.8855 Lu _0.2145 Ca _0.8 Si ₅ GeN _10.2 C _0.8 : (0.05Ce, 0.05Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 42

A high-power nitride fluorescent material with a chemical formula of La _1.8555 Lu _0.2145 Ca _0.8 Si ₅ GeN _10.2 C _0.8 : (0.05Ce, 0.08Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 43

A high-power nitride fluorescent material with a chemical formula of La _1.8355 Lu _0.2145 Ca _0.8 Si ₅ GeN _10.2 C _0.8 : (0.05Ce, 0.1Tb). The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Example 44

A high-power nitride fluorescent material with a chemical formula of La _1.9055 Lu _0.2145 Ca _0.8 Si ₅ GeN _10.2 C _0.8 : (0.05Ce, 0.03Tb). The preparation method of the nitride near-infrared fluorescent material comprises the following steps:

Mix a certain proportion of LaN, Si ₃ N ₄ , CeN, LuN, Ca ₃ N ₂ , Ge ₃ N ₄ , TbN, and SiC uniformly according to the stoichiometric ratio, put them into a tungsten crucible, and mix them in N ₂ /H ₂ Under the reduction of gas, sintering at 1600°C for 8 hours, the obtained fluorescent substance was crushed, washed and dried to finally obtain La _1.9055 Lu _0.2145 Ca _0.8 Si ₅ GeN _10.2 C _0.8 : (0.05Ce, 0.03Tb) phosphor. The scanning electron microscope image of the finally obtained nitride phosphor is shown in FIG. 3( b ), and the luminescence characteristics are shown in Table 1.

Comparative Example 5

A high-power nitride fluorescent material with a chemical formula of La _1.9355 Lu _0.2145 Ca _0.8 Si ₅ GeN _10.2 C _0.8 :0.05Ce. The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Comparative example 4

A high-power nitride fluorescent material with a chemical formula of La _1.9355 Lu _0.2145 Ca _0.8 Si ₅ SeN _10.2 C _0.8 :0.05Ce. The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Comparative example 3

A high-power nitride fluorescent material with a chemical formula of La _1.9355 Lu _0.2145 Ca _0.8 Si ₆ N _10.2 C _0.8 :0.05Ce. The preparation method of the nitride near-infrared fluorescent material is basically the same as that of Examples 1-7; the fluorescent properties of the obtained phosphor powder are shown in Table 1.

Comparative example 2

A high-power nitride fluorescent material with the formula: La _2.95 Si ₆ N ₁₁ :0.05Ce. The preparation method of the nitride near-infrared fluorescent material includes the following steps: uniformly mix a certain proportion of LaN, Si ₃ N ₄ and CeN according to the stoichiometric ratio, put them into a tungsten crucible, and mix them in N ₂ /H ₂ Under the reduction of the gas, it was sintered at 1600°C for 8 hours, and the obtained fluorescent substance was crushed, washed and dried to finally obtain La _2.95 Si ₆ N ₁₁ :0.05Ce phosphor. The fluorescence emission characteristics of the obtained phosphor powder are shown in Table 1.

Comparative example 1

A high-power nitride fluorescent material with the chemical formula: La _2.95 Si ₆ N ₁₁ :0.05Ce. The preparation method of the nitride near-infrared fluorescent material comprises the following steps: uniformly mixing a certain proportion of LaN, Si ₃ N ₄ and CeN according to a certain molar ratio, putting them into a tungsten crucible, and mixing them in a N ₂ /H ₂ mixed gas Under the reduction of 1400°C for 6 hours, the intermediate was obtained after crushing; then the obtained intermediate was uniformly mixed with LaN and Si ₃ N ₄ according to a certain molar ratio, and sintered at 1600°C for 8 hours in a reducing atmosphere of C , crushing, washing and drying the obtained fluorescent substance to finally obtain La _2.95 Si ₆ N ₁₁ :0.05Ce fluorescent powder. The fluorescence emission characteristics of the obtained phosphor powder are shown in Table 1.

Table 1

Figure 1 and Figure 2 are the excitation and emission spectra of Example 40. It can be seen from the figures that the nitride phosphor powder of this embodiment can be effectively excited in the ultraviolet and blue light regions, and the emission peak wavelength is located at 540nm, and the half maximum width is relatively large. Broad, with a shoulder around 580nm. According to Comparative Example 1 and Comparative Example 2, it can be seen that the initial strength and thermal stability of the sample prepared by the two-step method of the embodiment of the present invention have obvious advantages relative to the sample prepared by the traditional method. The scanning electron micrograph of the nitride phosphor obtained by the method, Fig. 3 (b) is the scanning electron micrograph of the nitride phosphor obtained according to the one-step method of Example 44, as can be seen from the comparison of (a) and (b) in Fig. 3 The crystallinity of the two-step method is better. Fig. 4 is a comparison chart of thermal stability between Comparative Example 1 and Example 40. It can be seen that the thermal stability of Example 40 of the present invention has been significantly improved.

It can be seen from Example 30 and Example 31 that when the molar content of Si is greater than or equal to 80%, the phosphor has better luminous intensity. It can be seen from Example 13 and Example 14: when the molar ratio of La and Lu is greater than 4:1, the phosphor improves the luminous intensity. It can be seen from Examples 33-37 or Examples 38-43 that when the molar ratio of La and Lu The effect is best when the ratio is between (4:10)-1.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (8)

1. The nitride fluorescent powder is applied to a high-power LED device and is characterized in that the chemical general formula of the nitride fluorescent powder is A_3-x-y-zM_xD₆(N_11-xC_x/2) (yCe, zR); wherein,

a is La and Lu, and the molar ratio of La to Lu is (4-10): 1,

m is at least one selected from Ca, Sr and Ba,

d is selected from at least one of Si, Ge, Ti, Se and Hf, and D includes Si; based on the mol percentage content of D as 100 percent, the mol content of Si is 80 to 90 percent,

r is at least one of Pr, Tb, Nd and Dy,

x is more than or equal to 0.001 and less than or equal to 2, y is more than or equal to 0.005 and less than or equal to 0.2, and z is more than or equal to 0.001 and less than or equal to 0.1.

2. The nitride phosphor according to claim 1, wherein in the chemical formula of the nitride phosphor, M is Ca; and/or

R is Pr and/or Tb.

3. The nitride phosphor of claim 1, wherein in the chemical formula of the nitride phosphor, D is at least one selected from the group consisting of Si, Ge, Ti, and Se, and D comprises Si.

4. The nitride phosphor of claim 3, wherein D is Si and Ge or D is Si and Se.

5. A method of preparing a nitride phosphor according to any of claims 1 to 4, comprising the steps of:

mixing nitride of first A, nitride of first D and CeN at N₂And H₂Performing a first sintering treatment under the reduction of (1) to obtain an intermediate;

adding a nitride of a second A, a carbide of a second D, a nitride of M and a nitride or fluoride of R into the intermediate, and performing second sintering treatment in a reducing atmosphere of C to obtain the nitride fluorescent powder;

wherein, the total molar amount of A of the nitride of the first A and the nitride of the second A, and the total molar amount of D of the nitride of the first D and the nitride of the second D are respectively the molar amounts of A and D in the chemical general formula of the nitride fluorescent powder.

6. The production method according to claim 5, wherein a ratio of a sum of a molar amount of the element A in the nitride of the first A and the element Ce in the CeN to a molar amount of the element D in the nitride of the first D is 1: 3; and/or

The temperature of the first sintering treatment is 1300-1500 ℃, and the time is 5-7 h; and/or

The temperature of the second sintering treatment is 1500-1700 ℃, and the time is 7-9 h.

7. A light-emitting device comprising an excitation light source and a fluorescent substance excited by the excitation light source, wherein the fluorescent substance is the nitride phosphor according to any one of claims 1 to 4 or the nitride phosphor obtained by the production method according to claim 5 or 6.

8. The light-emitting device according to claim 7, wherein the excitation light source is a semiconductor chip having an emission wavelength range of 330 to 480 nm.