CN100554370C - A kind of nitride luminescent material and preparation method thereof - Google Patents

Abstract

A kind of nitride luminescent material and preparation method thereof belongs to the luminescent material technical field.The chemical general formula of material is: Y _1-xM _x ^Y+Si ₃N _5-3x+xyO _3x-xy, wherein, M is Ce or Eu, y=3 or 2,0＜X＜1; M ^Y+Be luminescence center, at YSi ₃(N, O) ₅Mix rare-earth luminescent center M in the matrix ^Y+By the arc melting alloy Y _aSi _bWith Ce _cSi _d, grind; Get an amount of Y in proportion _aSi _b, Si ₃N ₄With Ce _cSi _dFull and uniform mixing, or Y _aSi _b, Si ₃N ₄With Eu ₂O ₃Full and uniform mixing places the high temperature solid state reaction stove with high temperature 1600-1800 ℃ sintering 1 to 10 hour after compressing tablet, and with the N of 1 to 10 atmospheric pressure ₂Atmosphere protection.Make thus and contain specific luminescence center M ^Y+With the nitride material of X value, its advantage is: have good fluorescence property in the visible light wave range scope, when being the optical excitation of 350～510nm with wavelength, can obtain the emission wavelength of wavelength between 400～600nm.

Description

A kind of nitride luminescent material and preparation method thereof

Technical field

The present invention relates to the luminescent material technical field, a kind of nitride luminescent material and preparation method thereof particularly is provided, with high purity Ln (Ln is La or Y), Si, Ce, Eu ₂O ₃With Si ₃N ₄Be raw material,, prepare nitride material with good luminescent properties by arc melting and high temperature solid-phase sintering.

Background technology

Up to now, multiple luminescent material has appearred, fields of society performance vital role.But great majority are with oxide compound, and sulfide or oxysulfide are matrix, and mix in these matrix a spot of transition metal ion or rare earth ion are luminescence center.The poor chemical stability of these compounds, after particularly comprehensive luminous efficiency and the temperature quenching characteristic, really material that can be practical is also few.Along with the development of society, they more and more are difficult to adapt to white light-emitting diodes illumination and the requirement of development such as modern plasma and Field Emission Display technology to material.

When with Ce ³⁺Or Eu ²⁺During as activator, its absorb and emission band be by

Transition causes.Because the 5d track exposes at skin, influenced greatly by residing crystalline environment on every side.Studies show that,

Excite and emission band position that transition causes depend primarily on 5d energy level position of centre of gravity and crystal field splitting.Mainly by the decision of chemical bond character, the 5d engery level cracking depends on crystal field intensity to 5d energy level position of centre of gravity.Along with rare earth activation ion and coordination anion covalent linkage composition increase on every side, the center of gravity of 5d energy level reduces, and excites accordingly with the emission band position and moves to the long wave direction.

Existing research points out that in all compounds, nitride has the strongest covalent linkage.And at present international and domestic research about nitride phosphor is reported seldom.Therefore, exploring novel long emission wavelength material in the nitride system of the prevailing stable chemical performance of covalent linkage is a kind of new research tendency.At present, also do not have about at LnSi ₃(N, O) ₅Doped Ce in the matrix ³⁺Or Eu ²⁺The report of luminescent properties.

Summary of the invention

The object of the present invention is to provide a kind of nitride luminescent material and preparation method thereof, obtained to have the nitride luminescent material of good luminescent properties.

Nitride luminescent material chemical general formula of the present invention is: Ln _1-xM _x ^Y+Si ₃N _5-3x+xyO _3x-xy, wherein, Ln is La or Y, M is Ce or Eu, y=3 or 2,0＜X＜1.Its excitation wavelength is positioned between 350 ~ 510nm, and emission wavelength is positioned between 400 ~ 600nm.

The present invention selects Ce for use ³⁺With Eu ²⁺Be luminescence center, with LnSi ₃(N, O) ₅Be matrix, with highly purified Ln, Si, Ce, Eu ₂O ₃And Si ₃N ₄Be raw material, utilize arc melting and high temperature solid-phase sintering prepared to go out a kind of Ce of containing ³⁺Or Eu ²⁺Nitride luminescent material Ln _1-xM _x ^Y+Si ₃N _5-3x+xyO _3x-xy(Ln is La or Y, and M is Ce or Eu, y=3 or 2).

The present invention is with chemical general formula Ln _1-xM _x ^Y+Si ₃N _5-3x+xyO _3x-xyIn X, i.e. rare-earth luminescent center Ce ³⁺Or Eu ²⁺Different percentage compositions, be to select the parameter batching of parameter point, wherein 0＜X＜1.

The objective of the invention is to implement by following method.With Ce ³⁺Or Eu ²⁺Be luminescence center, utilize purity to be higher than 99.5% metal Ln, simple substance Si, nanometer Si ₃N ₄Powder, metal Ce and Eu ₂O ₃Powder is a raw material, by arc melting, grind, compressing tablet, technologies such as high temperature solid-phase sintering, the nitride luminescent material that obtains the luminescent properties excellence with and preparation method thereof.

When luminescence center M is Ce, during y=3, concrete processing step is:

(1) be 5: 3 with molar ratio, 5: 4,1: 1,2: 3, the Ln and the Si of 3: 5 or 1: 2 placed electric arc furnace, carried out melting, the alloy Ln that makes when galvanic current is 70A ~ 120A _aSi _bFully grind to form powder subsequently, wherein, a and b are alloy Ln _aSi _bThe variable of middle element Ln and Si.

(2) be 5: 3 with molar ratio, 3: 2,5: 4,1: 1, the Ce and the Si of 3: 5 or 1: 2 placed electric arc furnace, carried out melting, the alloy Ce that makes when galvanic current is 70A～120A _cSi _dFully grind to form powder subsequently, wherein, c and d are alloy Ce _cSi _dThe variable of middle Elements C e and Si.

(3) according to general formula Ln _1-xM _x ^Y+Si ₃N _5-3x+xyO _3x-xy, with Ln _aSi _b, Ce _cSi _dAnd Si ₃N ₄According to molar ratio

Place mortar; With alcohol is dispersion agent, fully grinds, to be mixed evenly after, oven dry, compressing tablet; Then the sheet sample is loaded in the graphite furnace, in 1～10 atmospheric N ₂Protection down, with 1600 ~ 1800 ℃ of sintering 1～10 hour, furnace cooling.

When luminescence center M is Eu, during y=2, concrete processing step is:

(1) be 5: 3 with molar ratio, 5: 4,1: 1,2: 3, the Ln and the Si of 3: 5 or 1: 2 placed electric arc furnace, carried out melting, the alloy Ln that makes when galvanic current is 70A～120A _aSi _bFully grind to form powder subsequently, wherein, a and b are alloy Ln _aSi _bThe variable of middle element Ln and Si.

(2) according to general formula Ln _1-xM _x ^Y+Si ₃N _5-3x+xyO _3x-xy, with Ln _aSi _b, Eu ₂O ₃And Si ₃N ₄According to molar ratio

Place mortar; With alcohol is dispersion agent, fully grinds, to be mixed evenly after, oven dry, compressing tablet; Then the sheet sample is loaded in the graphite furnace, in 1～10 atmospheric N ₂Protection down, with 1600～1800 ℃ of sintering 1～10 hour, furnace cooling.

Advantage of the present invention is:

1, prepares with LnSi first ₃(N, O) ₅Luminescent material Ln for matrix _1-xM _x ^Y+Si ₃N _5-3x+xyO _3x-xy(Ln is La or Y; M is Ce or Eu, y=3 or 2,0＜X＜1), it has good luminescent properties, and excitation wavelength is positioned between 350 ~ 510nm, and emission wavelength is positioned between 400 ~ 600nm, is Ce ³⁺Or Eu ²⁺Wide emission peak.

2, utilize arc melting to make the raw material of LnSi and the final nitride material of CeSi alloy conduct.

3, adopt nano-powder Si ₃N ₄, increase speed of reaction, reduce the experimental installation requirement.

4, this nitride stable chemical performance, long service life.

Description of drawings

The nitride luminescent material that Fig. 1 obtains for embodiment 1 provided by the invention, the excitation spectrum when emission wavelength is 555nm.

The nitride luminescent material that Fig. 2 obtains for embodiment 1 provided by the invention, the emission spectrum when excitation wavelength is 420nm.

The nitride luminescent material that Fig. 3 obtains for embodiment 1 provided by the invention, the emission spectrum when excitation wavelength is 470nm.

The nitride luminescent material that Fig. 4 obtains for embodiment 2 provided by the invention, the excitation spectrum when emission wavelength is 555nm.

The nitride luminescent material that Fig. 5 obtains for embodiment 2 provided by the invention, the emission spectrum when excitation wavelength is 397nm.

The nitride luminescent material that Fig. 6 obtains for embodiment 3 provided by the invention, the excitation spectrum when emission wavelength is 510nm.

The nitride luminescent material that Fig. 7 obtains for embodiment 3 provided by the invention, the emission spectrum when excitation wavelength is 360nm.

The nitride luminescent material that Fig. 8 obtains for embodiment 4 provided by the invention, the excitation spectrum when emission wavelength is 550nm.

The nitride luminescent material that Fig. 9 obtains for embodiment 4 provided by the invention, the emission spectrum when excitation wavelength is 397nm.

Embodiment

Embodiment 1

Purity is higher than 99.5% Y and Si places electric arc furnace by 1: 1 molar ratio, melting under the electric current of 100A, (a=1 b=1), grinds to obtain alloy Y Si; Purity is higher than 99.5% Ce and Si, and the molar ratio by 1: 1 places electric arc furnace, melting under the electric current of 80A, and (c=1 d=1), grinds to obtain alloy CeSi.Select batching point X=0.05, with YSi, CeSi, Si ₃N ₄Powder 57: 3: 40 in molar ratio places mortar, is dispersion medium with the dehydrated alcohol, fully is ground to evenly oven dry, compressing tablet.Be loaded into then in the graphite furnace, at 1 atmospheric N ₂Under the atmosphere protection, 1800 ℃ of sintering of high temperature 2 hours, back furnace cooling.It is Y that the nitride that obtains finally embodies formula _0.95Ce _0.05Si ₃N ₅(wherein, Ln is Y, and M is Ce, y=3, X=0.05).Obtained nitride material has good luminescent properties.Its excite with emission spectrum shown in Fig. 1～3.

Embodiment 2

Purity is higher than 99.5% Y and Si places electric arc furnace by 1: 1 molar ratio, melting under the electric current of 100A, (a=1 b=1), grinds to obtain alloy Y Si.Select batching point X=0.1, with YSi, Eu ₂O ₃, Si ₃N ₄Powder was loaded in the mortar in 54: 3: 40 in molar ratio, was dispersion medium with the dehydrated alcohol, fully was ground to evenly oven dry, compressing tablet.Be loaded into then in the graphite furnace, at 1 atmospheric N ₂Under the atmosphere protection, 1800 ℃ of sintering of high temperature 2 hours, it is T that back furnace cooling, the nitride that obtains embody formula _0.9Eu _0.1Si ₃N _4.9O _0.1(wherein, Ln is Y, and M is Eu, y=2, X=0.1).Obtained nitride material has good luminescent properties.Its excite with emission spectrum shown in Fig. 4,5.

Embodiment 3

Purity is higher than 99.5% La and Si places electric arc furnace by 1: 1 molar ratio, melting under the electric current of 80A, (a=1 b=1), grinds to obtain alloy LaSi; Purity is higher than 99.5% Ce and Si, and the molar ratio by 1: 1 places electric arc furnace, melting under the electric current of 80A, and (c=1 d=1), grinds to obtain alloy CeSi.Select batching point X=0.02, with LaSi, CeSi, Si ₃N ₄Powder 147: 3: 100 in molar ratio places mortar, is dispersion medium with the dehydrated alcohol, fully is ground to evenly oven dry, compressing tablet.Be loaded into then in the graphite furnace, at 1 atmospheric N ₂Under the atmosphere protection, 1700 ℃ of sintering of high temperature 2 hours, it is La that back furnace cooling, the nitride that obtains embody formula _0.98Ce _0.02Si ₃N ₅(wherein, Ln is La, and M is Ce, y=3, X=0.02).Obtained nitride material has good luminescent properties.Its excite with emission spectrum shown in Fig. 6,7.

Embodiment 4

Purity is higher than 99.5% La and Si, places electric arc furnace by 1: 1 molar ratio, melting under the electric current of 80A, (a=1 b=1), grinds to obtain alloy Y Si.Select batching point X=0.05, with LaSi, Eu ₂O ₃, Si ₃N ₄The powder material was loaded in the mortar in 114: 3: 82 in molar ratio, was dispersion medium with the dehydrated alcohol, fully was ground to evenly oven dry, compressing tablet.Be loaded into then in the graphite furnace, at 1 atmospheric N ₂Under the atmosphere protection, 1700 ℃ of sintering of high temperature 2 hours, it is La that back furnace cooling, the nitride that obtains embody formula _0.95Eu _0.05Si ₃N _4.95O _0.05(wherein, Ln is La, and M is Eu, y=2, X=0.05).Obtained nitride material has good luminescent properties.Its excite with emission spectrum shown in Fig. 8,9.

Claims (4)

1, a kind of preparation method of nitride luminescent material is characterized in that: when luminescence center M is Ce, during y=3, technology is:

(1) be 5: 3 with molar ratio, 5: 4,1: 1,2: 3, the Ln and the Si of 3: 5 or 1: 2 placed electric arc furnace, carried out melting, the alloy Ln that makes when galvanic current is 70A～120A _aSi _bFully grind to form powder subsequently, wherein, a and b are alloy Ln _aSi _bThe variable of middle element Ln and Si;

(2) be 5: 3 with molar ratio, 3: 2,5: 4,1: 1, the Ce and the Si of 3: 5 or 1: 2 placed electric arc furnace, carried out melting, the alloy Ce that makes when galvanic current is 70A～120A _cSi _dFully grind to form powder subsequently, wherein, c and d are alloy Ce _cSi _dThe variable of middle Elements C e and Si;

(3) according to general formula Ln _1-xM _x ^Y+Si ₃N _5-3x+xyO _3x-xy, with Ln _aSi _b, Ce _cSi _dAnd Si ₃N ₄According to molar ratio $\frac{1-X}{a}:\frac{X}{c}:[1-\frac{b}{3a}(1-X)-\frac{d}{3c}X]$ Place mortar; With alcohol is dispersion agent, fully grinds, to be mixed evenly after, oven dry, compressing tablet; Then the sheet sample is loaded in the graphite furnace, at 1～10 atmospheric N ₂Protection down, with 1600～1800 ℃ of sintering 1～10 hour, furnace cooling;

The chemical general formula of described nitride luminescent material is Ln _1-xM _x ^Y+Si ₃N _5-3x+xyO _3x-xy, wherein, Ln is La or Y, M is Ce or Eu, y=3 or 2,0＜X＜1.

2, by right 1 described nitride luminescent material preparation method, it is characterized in that: raw material Ln, Si, Ce is with nanometer Si ₃N ₄Powder, purity is not less than 99.5%.

3, a kind of preparation method of nitride luminescent material is characterized in that: when luminescence center M is Eu, during y=2, technology is:

(1) be 5: 3 with molar ratio, 5: 4,1: 1,2: 3, the Ln and the Si of 3: 5 or 1: 2 placed electric arc furnace, carried out melting, the alloy Ln that makes when galvanic current is 70A～120A _aSi _bFully grind to form powder subsequently, wherein, a and b are alloy Ln _aSi _bThe variable of middle element Ln and Si;

(2) according to general formula Ln _1-xM _x ^Y+Si ₃N _5-3x+xyO _3x-xy, with Ln _aSi _b, Eu ₂O ₃And Si ₃N ₄According to molar ratio $\frac{1-X}{a}:\frac{X}{2}:[1-\frac{b}{3a}(1-X)]$ Place mortar; With alcohol is dispersion agent, fully grinds, to be mixed evenly after, oven dry, compressing tablet; Then the sheet sample is loaded in the graphite furnace, at 1～10 atmospheric N ₂Protection down, with 1600～1800 ℃ of sintering 1～10 hour, furnace cooling;

The chemical general formula of described nitride luminescent material is Ln _1-xM _x ^Y+Si ₃N _5-3x+xyO _3x-xy, wherein, Ln is La or Y, M is Ce or Eu, y=3 or 2,0＜X＜1.

4, by right 3 described nitride luminescent material preparation methods, it is characterized in that: raw material Ln, Si, Eu ₂O ₃With nanometer Si ₃N ₄Powder, purity is not less than 99.5%.

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