CN102925145A - aluminate compound fluorescent powder - Google Patents

Abstract

The invention discloses an aluminate compound phosphor and a preparation method thereof. It is found that partially replacing the Al/F element with Si/O elements can improve its optical properties. The general formula of this aluminate phosphor is Ca _a Sr _b Ba _c Al _d Si _e O _f F _g R _h , where R is one selected from the lanthanide series metal elements. In addition, the structure of the phosphor disclosed in the present invention can be fine-tuned by partially replacing the Al/F element with Si/O to change the proportion of different valences of lanthanide metals in the phosphor, thereby regulating its light-emitting properties.

Description

Aluminate Compound Phosphor Powder

technical field

The invention relates to a phosphor material, in particular to an aluminate compound phosphor powder in which Si/O elements are partially substituted for Al/F elements, which can improve its optical properties.

Background technique

With the evolution of civilization and the enhancement of energy conservation, carbon reduction and environmental protection awareness, countries are gradually replacing traditional light sources with light emitting diodes (Light Emitting Diode, LED), because light emitting diodes are small in size and low in power consumption (besides white light bulbs) One-tenth, one-half of fluorescent lamps), long life, good luminous efficiency, fast operation response, etc., can solve the problems that traditional light sources are difficult to overcome, so it has been used in signal lights, automotive light sources, displays, etc. Components, because they conform to the concept of green environmental protection emphasized today, are known as the "green lighting source" of the 21st century.

Nichia Chemical Company of Japan proposed in 1996 to excite cerium-doped yttrium aluminum garnet (Cerium-doped yttrium aluminum garnet; YAG:Ce) phosphor to produce yellow fluorescence by blue light LED, which can produce yellow fluorescence when mixed with blue light. Cool white light, this is the first white light diode, but because this white light lacks red light components, its color rendering is low, and this patent is restricted by Nichia patent. Since white light diodes must emit light in the full spectrum to achieve high color rendering and ideal color temperature, in addition to blue light diodes paired with YAG and red phosphors, there are also blue light diodes paired with green and red phosphors, and UV-LEDs paired with blue-green-red phosphors. In order to produce ideal color temperature (warm white light), UV-LEDs combined with three-color phosphors have better light emission efficiency, so the development of blue, green, and red phosphors suitable for ultraviolet light excitation Powder is currently the primary research topic.

In addition to the development of new host lattices, it is also a common research direction to dope the host lattices with other elements to replace the original host lattice elements so as to improve the luminescence. For example, Duan et al. The journal Chemistry of materials (Chemistry Materials, dx.doi.org/10.1021/cm103495j) published research on Re ₂ Si ₄ N ₆ C (RE=Lu, Y, Gd) series phosphors, that is, using RE/C to replace the original The M/N (M=Ba, Sr, Ca) in MRESi ₄ N ₇ uses the covalency of the C element and its rigid bonding characteristics to improve the stability of the host lattice, so the substitution of different elements To adjust the luminous properties and stability of the phosphor is also the main research goal at present.

Yu et al. published the preparation method and single crystal structure of Ca ₁₂ Al ₁₄ O ₃₂ F ₂ in the journal Cement and Concrete Research (Cement ConcreteRes, 1997, 27, 1439-1449) in 1997. The structure is represented by [AlO ₄ ] The tetrahedral structure, its unit cell belongs to the square crystal system, the space group is I43d, the oxygen atoms are used as bridges between the tetrahedrons, and the calcium atom coordinates with six oxygen and one fluorine atom, which belongs to the seven coordination, due to the formation in the structure The vacancies in the crystals are filled by fluorine atoms. Compared with the structure of Ca ₁₂ A ₇ , this crystal will be more stable and suitable for phosphors.

Contents of the invention

The object of the present invention is to provide a more stable phosphor.

The second object of the present invention is to provide a phosphor that can improve color rendering.

Another object of the present invention is to provide a simplified manufacturing method and reduce the cost of phosphor powder.

In order to achieve the above purpose, the aluminate compound phosphor powder disclosed by the present invention is synthesized by solid state reaction method under the conditions of sintering temperature T and sintering pressure P, and its formula is Ca _a Sr _b Ba _c Al _d Si _e O _f F _g R _h , where 10≤a+b+c+h≤12 (0≤a<12;0≤b<12;0≤c<12;0<h≤1),12<d+e≤14(12≦d<14;0<e≦2),30≦f≦34;,0<g≦2, R is a lanthanide metal element, and serves as the luminescent center of the phosphor. Wherein, the sintering temperature T used in the solid state reaction method is 1000-1400° C., and the sintering pressure Y is 0.1-0.9 MPa. The fluorescent powder can be excited by a light-emitting diode with a wavelength of 200-400nm, and its emission wavelength is 400-700nm. Wherein, the lanthanide metal element R is one of Ce, Eu, Pr, Nd, Sm, Tb, Er, Yb, Dy, so as to cause light emission in different ranges.

The phosphor powder disclosed by the present invention can be excited by ultraviolet light with a chip wavelength of 200-400nm, and the structure can be fine-tuned by partially replacing Al/F with Si/O, and the lanthanide series can be modulated by changing the coordination environment of the light-emitting center The proportion of different valences of metals in the crystal lattice controls its optical properties, and its light emission range can cover blue-green light and red light at the same time. It can improve its color rendering when combined with UV-LED synthetic white light, and use fewer types The powder can also simplify the production process and reduce the cost, which has great application potential and academic value.

Description of drawings

Fig. 1 is the diffraction pattern of its X-ray powder of preferred embodiment (A)～(E) of the present invention;

Fig. 2 is the emission spectrogram of preferred embodiment (A)～(E) of the present invention;

Figure 3A is the excitation spectrum (1) of the preferred embodiments (A)-(E) of the present invention;

Fig. 3B is the excitation spectrum diagram (2) of preferred embodiments (A) to (E) of the present invention;

Fig. 4 is a chromaticity coordinate diagram of preferred embodiments (A) to (E) of the present invention.

Detailed ways

The above and other technical features and advantages of the present invention will be described in more detail below in conjunction with the accompanying drawings, examples and test data.

The aluminate compound fluorescent powder of the present invention is prepared by a solid-state reaction method, its sintering temperature T is 1000-1400° C., and its sintering pressure P is 0.1-0.9 MPa. Represented by the chemical formula Ca _a Sr _b Ba _c Al _d Si _e O _f F _g R _h , where 10≤a+b+c+h≤12 (0≤a<12;0≤b<12;0≤c<12;0<h≤1),12<d+e≤14(12≤d<14;0<e≤2),30≤f≤34;,0<g≤2, wherein R is the lanthanide metal element Ce , Eu, Pr, Nd, Sm, Tb, Er, Yb, Dy one of them. The preferred embodiments (A) to (E) of the present invention are samples of Ca _11.9 Al _{14-x Six} O _32+X F _2-x :Eu _0.1 (x=0.1, 0.2, 0.3, 0.5, 0.6), and the formula is as follows As shown in the table:

As shown in FIG. 1 , it is the X-ray powder diffraction pattern of preferred embodiments (A) to (E) of the present invention. Ca _11.9 Al _14-x Six _{O 32+X} F _2-x :Eu _0.1 (x=0.1, 0.2, 0.3, 0.5, 0.6) samples prepared according to Examples (A)-(E) of the present invention, with The X-ray powder diffraction pattern identifies the purity of its crystal phase, and it can be found that the phosphor powder synthesized by the present invention is a pure phase.

3A and 3B are the excitation spectrum diagrams (1) and (2) of the preferred embodiments (A)-(E) of the present invention. The Ca _11.9 Al _14-x Six _{O 32+X} F _2-x :Eu _0.1 (x=0.1, 0.2, 0.3, 0.5, 0.6) samples prepared in Examples (A)-(E) of the present invention can be Excited by light-emitting diodes with a wavelength of 200-400nm, especially as the amount of Si/O increases, the spectral excitation effect near the wavelength of 250nm and 325nm is more significant.

FIG. 2 and FIG. 4 are emission spectrum diagrams and chromaticity coordinate diagrams of preferred embodiments (A)-(E) of the present invention. As shown in the figure, it can be known that the Ca _11.9 Al _{14-x Six} O _32+X F _2-x :Eu _0.1 (x=0.1, 0.2, 0.3 ^{. _} For the light intensity in the light range, with the slight increase of Si/O and the corresponding decrease of Al/F, the intensity of blue-green light shows a great increase, while the intensity of red light decreases accordingly. In addition, the emission spectrum data is converted with the chromaticity coordinate diagram formulated by the International Commission on Illumination to obtain the chromaticity coordinates of each phosphor, which are respectively marked on the coordinate diagram, so that the Ca _11.9 Al synthesized in this preferred embodiment can be seen. _{14-x Six} O _32+X F _2-x : Eu _0.1 can adjust the light emission from the red range to the blue range as the value of x increases.

Accordingly, the phosphor powder disclosed in the present invention can fine-tune the structure by partially replacing Al/F with Si/O, and adjust the existence of different valence numbers of lanthanide metals in the crystal lattice by changing the coordination environment of the light-emitting center. Ratio, and then control its optical properties, and its light emission range can cover blue-green light and red light at the same time, with UV-LED synthetic white light can improve its color rendering, and the aluminate compound phosphor Ca in this preferred embodiment _11.9 Al _14-x Six _{O 32+X} F _2-x :Eu _0.1 , the raw materials used include CaCO ₃ , Al ₂ O ₃ , SiO ₂ , CaF ₂ , Eu ₂ O ₃ After uniformly mixing and grinding with a mortar, place it at 1250° C. and sinter for 6 hours in an atmosphere of hydrogen (5%)-nitrogen (95%) to obtain the product. The production process is simple, which is conducive to mass production, and the use of fewer types of powder can also simplify the production process and reduce costs, which has great application potential and academic value.

The various embodiments listed in this application are only preferred specific embodiments of the present invention, and are not intended to limit the scope of the present invention. Any modifications or changes made by anyone without departing from the spirit of the present invention shall fall within the patent scope of the present invention.

Claims (6)

1. an aluminate class compound fluorescent material is synthetic with solid state reaction under the condition of sintering temperature T and sintering pressure P, and its prescription is Ca _aSr _bBa _cAl _dSi _eO _fF _gR _h, (0≤a＜12,10≤a+b+c+h≤12 wherein; 0≤b＜12; 0≤c＜12; 0＜h≤1), (12≤d＜14,12＜d+e≤14; 0＜e≤2), 30≤f≤34; , 0＜g≤2, wherein R is lanthanide element.

2. fluorescent material as claimed in claim 1 is characterized in that: described lanthanide element R is a kind of among Ce, Eu, Pr, Nd, Sm, Tb, Er, Yb or the Dy.

3. fluorescent material as claimed in claim 1, it is characterized in that: the sintering temperature T of described solid state reaction is 1000～1400 ℃.

4. fluorescent material as claimed in claim 1, it is characterized in that: the sintering pressure P of described solid state reaction is 0.1～0.9MPa.

5. fluorescent material as claimed in claim 1 is characterized in that: described fluorescent material can be that the photodiode of 200～400nm excites by wavelength.

6. fluorescent material as claimed in claim 1, it is characterized in that: the radiation wavelength of described fluorescent material is 400～700nm.

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