CN1204083C

CN1204083C - Prepn of ion doped yttrium aluminium garnet nano-powder

Info

Publication number: CN1204083C
Application number: CN 02136705
Authority: CN
Inventors: 张俊计; 宁金威; 刘学建; 潘裕柏; 黄莉萍
Original assignee: Shanghai Institute of Ceramics of CAS
Current assignee: Shanghai Institute of Ceramics of CAS
Priority date: 2002-08-28
Filing date: 2002-08-28
Publication date: 2005-06-01
Anticipated expiration: 2022-08-28
Also published as: CN1398817A

Abstract

The present invention relates to a method for preparing nanometer yttrium aluminum garnet ceramic powder by a method of combining solation-gelation and combustion synthesis. Single-phase nanometer grade pure yttrium aluminum garnet powder or doped yttrium aluminum garnet powder can be obtained at lower temperature by using raw materials selected by the method and the technical conditions provided by the method; the nanometer yttrium aluminum garnet ceramic powder of the present invention has a general formula of Y<3-x>Me<x>Al5O12 or Y3Al<5-x>Me<x>O12, wherein Me is a rare earth element, or one or two transition metal elements, and x is more than or equal to 0.01 and is less than or equal to 0.30. The method has the main characteristics that metal nitrate and oxide are used as raw materials, citric acid is used as gelatinizer and fuel, and a precursor is obtained by the processes of solation-gelation and combustion and then is calcined in the temperature range of 800 to 1000 DEG C to obtain single-phase yttrium aluminum garnet ceramic powder with the particle size of 40 to 100 nm. The method has the outstanding characteristics of simple technology, high speed and higher activity of the prepared powder and can be convenient to realize the uniform doping of various activator ions on an ion level.

Description

The preparation method of the nanometer yttrium aluminium garnet powder of ion doping

Technical field

The present invention relates to a kind of preparation method of nanometer yttrium aluminium garnet powder, relate to or rather and a kind ofly prepare nanometer yttrium aluminum garnet based ceramic powder body, belong to field of fine chemical with sol-gel and the synthetic method that combines of burning.

Background technology

Yttrium aluminum garnet (Y ₃Al ₅O ₁₂, it is little that YAG) pottery has creep, high-temperature oxidation resistant, and advantage such as thermal conductivity is low can be used for fields such as insulation and refractory materials.YAG belongs to tesseral system, does not have birefringence effect, can be made into the crystalline ceramics with excellent optical property, has important potential application foreground as solid laser material to replace the YAG monocrystalline.The YAG powder of other ion (mainly being rare earth element ion and transition metal ion) of mixing can be used as the ultrashort afterglow material, is used for fields such as cathode ray tube screen, high resolution projection TV and indicating meter.

Traditionally, the method for the synthetic employing solid state reaction of YAG powder is with mixed uniformly Al ₂O ₃And Y ₂O ₃Powder is heat-treated under the high temperature more than 1600 ℃, and this method technology is simple, easily produces in batches.Shortcoming is easily to introduce impurity in the mechanical milling process, in the calcinate except that principal crystalline phase YAG, often residual a small amount of intermediate phase YAM (Y ₄Al ₂O ₉) and YAP (YAlO ₃).In recent years, wet chemical method successfully is used for the synthetic of YAG powder." method for preparing the YAG powder " (patent No. JP2001270714) as people such as Japanese IKEGAMI TAKAYASU invention, make raw material with yttrium carbonate and dawsonite, make the solution that contains carbonate and sulfonium ion, pH value by regulator solution forms precipitation, throw out is heat-treated at 800-1300, and obtaining particle diameter is the single-phase YAG powder of 40-400nm." a kind of preparation method of nanometer yttrium aluminium garnet powder without coacervate " that Wang Hongzhi, high Lian propose, patent of invention (CN1076010c), be that inorganic salt solution with Y and Al is a raw material, obtain gelatinous precipitate by regulating the pH value and adding tensio-active agent, calcining between 700-1300 ℃, the YAG powder of acquisition crystal grain 20-100 nanometer.Above-mentioned two patents all belong to the precipitator method, shortcomings such as lifetime is long, process is complicated, the easy reunion of powder.If introduce the third ion except that Y and Al, then, make the first postprecipitation of different ions easily and cause powder to become skewness because deposition condition (mainly being the pH value) is difficult to control.

People (Michael Veith, et al, Low temperature synthesisof nanocrystall ine Y such as Michael Veith ₃Al ₅O ₁₂(YAG) and Ce-doped Y ₃Al ₅O ₁₂Via differentsol-gel methods.J.Mater.Chem., 1999 (12) 3069-3079) utilize sol-gel method to prepare nano level yttrium aluminum garnet (YAG) and mix the yttrium aluminum garnet (Ce:YAG) of Ce, it is raw material that this method adopts metal alkoxide.Metal alkoxide preparation process complexity so the cost height costs an arm and a leg, is unsuitable for large-scale production.People (Lauren E.Shea such as Lauren E.Shea, et al, Synthesis ofred-emitting, small particle size luminescent oxides using an optimizedcombustion process, J.Am.Ceram.Soc., 79[12] 3257-65) reported the method for mixing the yttrium aluminum garnet (YAG:Cr) of Cr with the combustion synthesis method preparation, because the severity and the burst of reacting in this method, the shape of prepared powder and size are all wayward.

Summary of the invention

The object of the present invention is to provide a kind of method of the quick YAG of preparation powder.Advantages such as this method has fast, safety, the easy control of process.Another outstanding advantage of the present invention is other ion that can mix easily as required, is implemented in the uniform mixing on the ion concentration, makes dopant ion enter lattice in the mode of solid solution.

The method of the quick YAG of the preparation powder that the present invention proposes is a kind of sol-gel and synthetic the combining of burning to be prepared the method for nano level YAG powder, is to utilize gelling and redox reaction between metal nitrate and the citric acid to realize.The nanometer yttrium aluminium garnet powder of nanometer yttrium aluminium garnet powder provided by the invention or ion doping, its dopant ion can partly replace Y ₃Al ₅O ₁₂In Y ion or Al ion.General formula after the doping can be expressed as: Y _3-xMe _xAl ₅O ₁₂Or Y ₃Al _5-xMe _xO ₁₂, Me is a dopant ion in the formula, is rare earth ion or transition metal ion such as Nd at least, Eu, and Tb, Ce, one or both among the Cr, x are represented the gram molecular weight of dopant ion, common 0.01≤x≤0.30.Metal nitrate provides metal ion required in the final product; Citric acid plays fuel simultaneously as jelling agent.Make between metal nitrate and the citric acid by heating and to have an effect, form fluffy presoma through step of reaction such as colloidal sol, gel, burnings, presoma obtains final oxide powder through Overheating Treatment again.Specifically may further comprise the steps:

1. the selection of raw material: metal ion Y and Al introduce with the form of nitrate, and other dopant ion can be selected corresponding nitrate or oxide compound.Citric acid is commercial analytical pure level.

2. the preparation of solution: with deionized water or Virahol is solvent.Various nitrate and (or) consumption of oxide compound calculates by various ionic content in the desired final product.The consumption of citric acid is the 25%-120% of nitrate weight.

3. the formation of colloidal sol: the solution of configuration is placed on the magnetic stirring apparatus, in 60 ℃ of-70 ℃ of stirred for several that heating does not stop hour until forming colloidal sol.

4. the formation of gel: Heating temperature is elevated to 80 ℃-90 ℃ and continuation stirring, forms transparent gel.

5. the formation of presoma: gel is heated to 120-180 ℃, combustion reactions takes place and supervene tawny smog, form fluffy precursor powder.

6. thermal treatment: heat treated purpose is in order to guarantee to obtain monophasic YAG powder, and eliminates residual a small amount of C and N in the powder.The too high meeting of temperature makes grain growth and form hard aggregation.Because under processing condition of the present invention, promptly form the YAG phase since 800 ℃, so suitable heat treated temperature is 800-1000 ℃.

With the prepared powder of method provided by the invention, because heat treated temperature is lower, powder granularity is little, and the sintering activity height is applicable to the powder as the transparent YAG pottery of preparation; Can add activator ion easily, realize the uniform mixing of activator ion, change thermal treatment temp, can obtain the fluorescent material that different grain size distributes, be used for fields such as cathode ray tube screen, high resolution projection TV and indicating meter at atomic level.

Description of drawings

Fig. 1 presses the XRD figure spectrum of the nanometer YAG powder of example 1 preparation, shows that product is single YAG phase.

Fig. 2 presses the electron diffraction photo of the nanometer YAG powder of example 1 preparation, and demonstrate product and belong to isometric system, and complete crystallization.

Fig. 3 presses the transmission electron microscope photo of the nanometer YAG powder of example 1 preparation, shows that powder is a nano level, epigranular.

Fig. 4 presses the fluorescence spectrum of Eu:YAG nano-powder under ultraviolet excitation of example 5 preparations, and X-coordinate is wavelength (nm), and ordinate zou is a luminous intensity.

Fig. 5 presses the Y of example 6 preparations _2.936Ce _0.004Tb _0.06Al ₅O ₁₂The fluorescence spectrum of nano-powder under ultraviolet excitation, the same Fig. 4 of the physical meaning of its X-coordinate and ordinate zou.

Embodiment

Following example is unrestricted the present invention in order further to illustrate technological process feature of the present invention.

Example 1

Get the 20g aluminum nitrate, the 12.252g Yttrium trinitrate, the 17.9528g citric acid is dissolved in the 30ml deionized water, stirs to form uniform solution.The beaker that fills this solution is placed on the magnetic stirring apparatus, be heated to 60 ℃ and do not stop to stir, form colloidal sol after a few hours.Be warming up to 80 ℃ and continuation stirring, form xanchromatic transparence gel.Gel put into be preheated to 150 ℃ box-type furnace, through the final loose precursor powder that forms oyster that burns.Precursor powder promptly obtained the finished product of white in two hours through 900 ℃ of thermal treatments.Its key technical indexes sees Table 1.

Table 1

Example	Product	Color	Specific surface area (rice ²/ gram)	Particle diameter (nanometer)
Example	Product	Color	Specific surface area (rice ²/ gram)	Particle diameter (nanometer)	?1	?Y ₃Al ₅O ₁₂	White	31	?40
?2	?Y _2.94Nd _0.06Al ₅O ₁₂	White	22	?60	?1	?Y ₃Al ₅O ₁₂	White	31	?40
?2	?Y _2.94Nd _0.06Al ₅O ₁₂	White	22	?60	?3	?Y ₃Al _4.75Cr _0.25O ₁₂	Green	31	?40
?4	?Y _2.85Tb _0.15Al ₅O ₁₂	Faint yellow	28	?45	?3	?Y ₃Al _4.75Cr _0.25O ₁₂	Green	31	?40
?4	?Y _2.85Tb _0.15Al ₅O ₁₂	Faint yellow	28	?45	?5	?Y _2.85Eu _0.15Al ₅O ₁₂	White	15	?90
?6	?Y _2.936Ce _0.004Tb _0.06Al ₅?O ₁₂	Faint yellow	31	?40	?5	?Y _2.85Eu _0.15Al ₅O ₁₂	White	15	?90

Accompanying drawing 1 is the XRD figure spectrum of product, shows that product is single YAG phase.

Accompanying drawing 2 is the electron diffraction photo of prepared powder, demonstrates product and belongs to isometric system, and complete crystallization.

Accompanying drawing 3 is the transmission electron microscope photo of prepared powder, shows that powder is a nano level, epigranular.

Example 2

Get the 0.0538g Neodymium trioxide and be dissolved in the excessive nitric acid, then with the 10g aluminum nitrate, 6.004g Yttrium trinitrate and 8.9629g citric acid together are dissolved in the 20ml Virahol, stir to form lilac homogeneous solution.Place heating and stirring on the magnetic stirring apparatus, process is with example 1.Obtaining Nd content at last is the Nd:YAG nano-powder of 2.0mol% (with respect to Y).Its XRD figure spectrum and images of transmissive electron microscope feature are with example 1.

The key technical indexes sees Table 1.

Example 3

Get the 20g aluminum nitrate, the 12.8979g Yttrium trinitrate, 17.9528g citric acid and 1.1229g chromium nitrate are dissolved in the 30ml deionized water, stir to form blue homogeneous solution.Place heating and stirring on the magnetic stirring apparatus, process is with example 1.The powder of presoma is blue.Thermal treatment is two hours under 900 ℃ condition, and obtaining Cr content is the Cr:YAG nano-powder of 5.0mol% (with respect to Al).Its XRD figure spectrum and images of transmissive electron microscope feature are with example 1.The key technical indexes sees Table 1.

Example 4

Get the 0.299g terbium sesquioxide and be dissolved in the excessive nitric acid, then with the 20g aluminum nitrate, 11.6404g Yttrium trinitrate and 8.9629g citric acid together are dissolved in the 30ml deionized water, stir to form colourless homogeneous solution.Place heating and stirring on the magnetic stirring apparatus, process is with example 1.Obtaining Tb content at last is the Tb:YAG nano-powder of 5.0mol% (with respect to Y).Its XRD figure spectrum and images of transmissive electron microscope feature are with example 1.

The key technical indexes sees Table 1.

Example 5

Get the 0.2815g europium sesquioxide and be dissolved in the excessive nitric acid, then with the 20g aluminum nitrate, 11.6404g Yttrium trinitrate and 35.9056g citric acid together are dissolved in the 30ml deionized water, stir to form colourless homogeneous solution.Place heating and stirring on the magnetic stirring apparatus, process is with example 1.Obtaining Eu content at last is the Eu:YAG nano-powder of 5.0mol% (with respect to Y).Accompanying drawing 4 is the fluorescence spectrum of Eu:YAG nano-powder under ultraviolet excitation, and spectral signature shows Eu ³⁺Form with solid solution has entered the YAG lattice.The key technical indexes sees Table 1.

Example 6

Get 0.011g cerium oxide and 0.1794g terbium sesquioxide and be dissolved in the excessive nitric acid, then with the 30g aluminum nitrate, 17.9875g Yttrium trinitrate and 29.9292g citric acid together are dissolved in the 30ml deionized water, stir to form colourless homogeneous solution.Place heating and stirring on the magnetic stirring apparatus, process is with example 1.Obtaining chemical formula at last is Y _2.936Ce _0.004Tb _0.06Al ₅O ₁₂Nano-powder.Accompanying drawing 5 is the fluorescence spectrum of this powder under ultraviolet excitation.The key technical indexes sees Table 1.

Claims

1. the preparation method of the nanometer yttrium aluminium garnet powder of an ion doping is characterized in that specifically comprising:

(1) solution preparation, wherein Al and Y introduce with the form of nitrate;

(2) form colloidal sol;

(3) form gel and presoma, as jelling agent and fuel, the consumption of citric acid is the 25%-120% of nitrate weight with citric acid;

(4) last, synthetic presoma is heat-treated to burning.

2. press the preparation method of the nanometer yttrium aluminium garnet powder of the described a kind of ion doping of claim 1, it is characterized in that:

(1) formation temperature of colloidal sol is 60 ℃-70 ℃, does not stop to stir;

(2) formation temperature of gel is controlled at 80 ℃-90 ℃ temperature range;

(3) temperature of combustion reactions formation presoma is 120-180 ℃;

(4) the heat treated temperature of presoma is between 800-1000 ℃.

3. press the preparation method of the nanometer yttrium aluminium garnet powder of the described a kind of ion doping of claim 1, it is characterized in that: rare earth or transition metal ion adopt corresponding metal nitrate or oxide compound, and solvent is deionized water or Virahol.