CN103834387A - Fluorescent material crystal and preparation method thereof - Google Patents

Abstract

The invention relates to a fluorescent material crystal, which has a chemical composition expression of Sr0.946Si2O2N2:Eu0.05, Ho0.002, Na0.002, and has X ray powder diffraction pattern at 2 theta of 12.6, 13.6, 16.5, 20.3 and 24.1. The fluorescent material crystal has high color purity and improved brightness, and can be excited by optical radiation in required wavelength range. The invention also provides an optical device and a display device including the above fluorescent crystal.

Description

A kind of fluorescent material crystal and preparation method thereof

Technical field

The present invention relates to luminescent material technical field, relate in particular to a kind of fluorescent material crystal and preparation method thereof.

Background technology

The distinguishing feature such as that white light emitting diode (LED) has is energy-conservation, long service life, environmental protection, start time are short, sound construction, volume are little is to have in recent years one of new and high technology of development prospect most.Along with the progress of technology, be expected to replace incandescent light, luminescent lamp, the lamp etc. of receiving becomes lighting source of new generation.

The method of light conversion is to manufacture at present the most frequently used also proven technique comparatively of white light LEDs, sees the earliest first commercial white light LEDs of Japanese Ya chemical company in 1996 invention, and it is by conjunction with InGaN base blue-ray LED chip and YAG:Ce ³⁺yellow fluorescent powder is realized.YAG:Ce ³⁺fluorescent material is the generally acknowledged the highest semiconductor lighting fluorescent material of luminous efficiency, and production cost is low, technical maturity, still, and YAG:Ce ³⁺in the emmission spectrum of fluorescent material, lack red wave band, color developing is poor, is difficult to meet the requirement of low colour temperature illumination, meanwhile, its poor heat stability, luminous efficiency sharply declines with the increase of temperature.The oxynitride fluorescent powder occurring recently shows good calorifics, chemical stability and the matching with LED chip, is subject to people and more and more pays close attention to.CaSi ₂o ₂n ₂: Eu ²⁺as a kind of novel yellow-green fluorescence powder, be expected to replace YAG:Ce ³⁺.But, with YAG:Ce ³⁺compare CaSi ₂o ₂n ₂: Eu ²⁺the luminous intensity of fluorescent material need further raising.

At present, the method that improves light-emitting phosphor intensity mainly contains following two kinds: a kind of is that preparation technology by optimizing fluorescent material realizes, the Ca-α-SiAION:Yb making as high-temperature solid phase reaction method ²⁺fluorescent material grinds again, and then secondary calcination 24h at 1700 DEG C makes the luminous intensity of fluorescent material improve approximately 80% (J. Phys. Chem. B, 2005,9490-9494).But this method production cycle is long, energy consumption is large, and easily causes fluorescent powder grain excessively to be grown up;

Another kind is by ion co-doped method, as passes through Li doped ⁺, Na ⁺or K ⁺ion makes SrZnO ₂: Eu ³⁺the luminous intensity of fluorescent material is improved.

Summary of the invention

Therefore, the object of this invention is to provide technical problem to be solved by this invention and be to provide a kind of new fluor crystal and preparation method thereof, the luminous strength ratio CaSi of this fluorescent material ₂o ₂n ₂: Eu ²⁺being significantly increased of fluorescent material; The each method technique of this system is simple, and required production unit is simple, is easy to realize suitability for industrialized production, has a good application prospect.

The chemical constitution expression of described fluorescent material is: Sr _0.946si ₂o ₂n ₂: Eu _0.05, Ho _0.002, Na _0.002, it has 2 θ at approximately 12.6,13.6,16.5,20.3 and 24.1 X-ray powder diffraction figure.

According to a second aspect of the present invention, a kind of preparation method of fluorescent material crystal is provided, comprise the following steps:

(1) after in molar ratio Strontium carbonate powder, silicon-dioxide, silicon nitride, europium sesquioxide, Holmium trioxide and sodium carbonate being mixed, grind, be dried, sieve; Again under nitrogen atmosphere with 1400 ~ 1500 DEG C of calcination 5 ~ 10h;

(2) above-mentioned burning forging product pulverized, wash, be dried, to obtain final product.

The concrete technology of the mixing described in described step (1) for to mix Strontium carbonate powder, silicon-dioxide, silicon nitride, europium sesquioxide, Holmium trioxide and sodium carbonate in 10 ~ 20mL dehydrated alcohol; 1 ~ 4h is ground in described being ground in planetary ball mill, and rotating speed is 300 ~ 350r/min.

The order number sieving in described step (1) is 150 ~ 200 orders.

In described step (1), in nitrogen atmosphere, stream of nitrogen gas amount is 250 ~ 300mL/min.

Temperature rise rate when the middle calcination of described step (1) is 2 ~ 3 DEG C/min, is incubated 0.5 ~ 1h while rising to 800 DEG C.

Dry concrete technology in described step (1) and (2) is 600 ~ 800 DEG C of drying temperatures, time of drying 8 ~ 12h.

Pulverizing in described step (2) is to pulverize in agate mortar.

Washing in described step (2) is pickling 1 ~ 2h, then successively with distilled water and each centrifugal the washing 3 times of absolute ethanol washing.

In described pickling, pickle solution is the hydrochloric acid soln of volumetric concentration 5 ~ 10%.

The preparation method of fluorescent material crystal of the present invention, technique is simple, with low cost, and the fluorescent material crystal of stating making is not introduced other impurity, and quality product is high, can be widely used in the manufacture of luminescent material.

Brief description of the drawings

Fig. 1 is Sr prepared by the embodiment of the present invention 1 _0.946si ₂o ₂n ₂: Eu _0.05, Ho _0.002, Na _0.002fluorescent material crystal (representing with 1) and commercially available CaSi ₂o ₂n ₂: Eu ²⁺the emmission spectrum comparison diagram of (representing with 2).

Wherein, utilizing emitted light spectrogram is to obtain through 200 ~ 250nm optical excitation.

Fig. 2 is the characteristic X-ray powder diagram of embodiment 1 fluorescent material crystal.

Embodiment

In powder X-ray ray diffraction (XRD), use Cu K α 1 as X x ray tube, at room temperature use powder X-ray ray diffraction device RINT2200/Ultima+ (RIGAKU) or X'Pert Pro MPD (PANalytical) to measure within the scope of the 2 θ diffraction angle of 2 ° to 35 °.For used each diffraction instrument, measuring condition is as follows.

Diffraction instrument: RINT2200/Ultima+ (RIGAKU)

Tube current: 40mA, tube voltage: 40kV, sweep velocity: 4 °/minute

Diffraction instrument: X'Pert Pro MPD (PANalytical)

Tube current: 40 mA, tube voltage: 45kV, sweep velocity: 40.1 °/minute

Although 2 θ values generally illustrate 0.2 ° of about scholar's error, may cause larger error due to measuring condition etc.

Use thermogravimetric/differential thermal analyzer TG/SDTA851e (TG/DTA) (Mettler Toledo) or differential scanning calorimeter DSC821e (DSC), in the dry nitrogen air-flow of 40ml/ minute and under the intensification degree speed of 10 DEG C/min, carry out heat analysis.

Embodiment 1:

Sr _0.946si ₂o ₂n ₂: Eu _0.05, Ho _0.002, Na _0.002the preparation of fluorescent material crystal

By Strontium carbonate powder 0. 0189mol, silicon-dioxide 0.01mol, silicon nitride 0.01mol, europium sesquioxide 0. 0005mol, Holmium trioxide 0.00002mol, sodium carbonate 0.00002mol and 12mL dehydrated alcohol are added on ball milling 4h in planetary ball mill, and rotating speed is 300r/min, after mixing by raw material in 80 DEG C of oven drying 12h.After being sieved by 200 object standard sieves, the batching obtaining puts into aluminum oxide porcelain boat; be placed in tube-type atmosphere furnace; under nitrogen atmosphere, be warming up to 800 DEG C; nitrogen flow is 280m l/min; heat-up rate is 3 DEG C/min; at this temperature, be incubated 1h, then be warming up to 1400 DEG C with identical heat-up rate, insulation 6h; Then, cool to room temperature rapidly, after grinding in the auspicious mortar of agate, powder being distributed to volumetric concentration is in 10% hydrochloric acid soln, magnetic agitation 1h, then with distilled water and each centrifugal the washing 3 times of dehydrated alcohol is finally dried 8h and get final product in the baking oven of 80 DEG C.

Fig. 1 is Sr prepared by the embodiment of the present invention 1 _0.946si ₂o ₂n ₂: Eu _0.05, Ho _0.002, Na _0.002fluorescent material crystal and commercially available CaSi ₂o ₂n ₂: Eu ²⁺emmission spectrum comparison diagram.As shown in Figure 1, in figure, 1 is the emmission spectrum of the fluorescent material crystal prepared of the embodiment of the present invention 1, the 2nd, and the emmission spectrum of commercially available fluorescent material.Can find out fluorescent material crystal and the CaSi of the embodiment of the present invention 1 by contrast ₂o ₂n ₂: Eu ²⁺fluorescent material is compared, and luminous intensity is approximately 2.3 times of the latter.

Claims (2)

1. a fluorescent material crystal, is characterized in that its chemical constitution expression is: Sr _0.946si ₂o ₂n ₂: Eu _0.05, Ho _0.002, Na _0.002, it has 2 θ at approximately 12.6,13.6,16.5,20.3 and 24.1 X-ray powder diffraction figure.

2. a light-emitting device, comprises fluorescent material crystal claimed in claim 1.

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