CN103361050A - A kind of Sb3+ activated LED green phosphor and preparation method thereof - Google Patents

Abstract

The invention discloses a Sb ³⁺ activated Cd _1-x WO ₄ :Sb ³⁺ _x system LED green fluorescent powder and a preparation method thereof, wherein 0.001≦x≦0.03. First, weigh the raw materials according to the stoichiometric ratio of each element in the chemical expression of the fluorescent powder, dissolve the compound containing Sb ³⁺ into an antimony nitrate solution under the condition of heating and stirring in a water bath, and dissolve the compound containing Cd ²⁺ and WO ₄ ^2- Dissolve the compounds into their respective solutions, fully mix the antimony nitrate and the solution containing Cd ²⁺ , then add dropwise to the tungstate solution, filter the formed precipitate and dry it, grind the prepared precursor and put it in the crucible Calcined in the air, cooled to room temperature, taken out and ground to obtain the green fluorescent powder of the system. The prepared fluorescent powder has strong emission at 450-600nm, and can be used as green fluorescent powder for LEDs excited by ultraviolet or near ultraviolet chips.

Description

A kind of Sb3+ activated LED green phosphor and preparation method thereof

technical field

The invention relates to an inorganic luminescent material and a preparation method thereof, in particular to a Sb ³⁺ activated LED green fluorescent powder and a preparation method thereof.

Background technique

Light-emitting diode (LED) has the advantages of high brightness, low energy consumption, long life, small size, shock resistance, environmental protection, and fast response. It is a new type of solid-state light source and has great application prospects in the field of lighting and display. Using blue LED chips to excite yellow YAG:Ce ³⁺ phosphor is the most mature way to realize white light at present, but the luminous color of this type of white light is greatly affected by the current, and due to the lack of red light components, the display of this white light The color index is low. In order to solve this problem, people have begun to use ultraviolet-near ultraviolet chips to excite three primary color phosphors to realize white light LED. Since the human eye is not sensitive to ultraviolet-near-ultraviolet light, the luminous color of this type of LED is only determined by the luminous color of the phosphor, but currently there are few green phosphors that can be excited by light in the 350-410 nm band, and the commonly used sulfide The chemical properties of the series of green phosphors are unstable, and the synthesis temperature of the aluminate system green phosphors is high. Therefore, the development of green phosphors suitable for effective excitation of 350-410 nm ultraviolet-near ultraviolet light has important practical significance and theoretical value. On the one hand, green phosphor can be used to prepare pure green LEDs, and its luminous efficiency is higher than that of green LED chips; on the other hand, it can be used to form the green part of white LEDs. .

Contents of the invention

The object of the present invention is to provide a novel Sb ³⁺ activated LED green phosphor with stable chemical properties and a preparation method thereof.

In order to achieve the above purpose, the technical solution adopted by the present invention is to provide a tungstate LED phosphor powder excited by trivalent antimony ions Sb ³⁺ , the chemical formula is a kind of Sb ³⁺ activated LED green phosphor powder, and the chemical formula is Cd _{1- x} WO ₄ :Sb ³⁺ _x , where 0.001≦x≦0.03.

The present invention provides the preparation method of the LED green fluorescent powder activated by this Sb ³⁺ , comprising the following steps:

1) Weigh the raw materials according to the molar ratio of each element in the chemical expression Cd _1-x WO ₄ :Sb ³⁺ _x , wherein, 0.001≦x≦0.03; the raw materials contain antimony ions Sb ³⁺ and cadmium ions Cd ^{2 +} , compound of tungstate ion WO ₄ ^2- ;

2) Dissolve ^the compounds _containing antimony ions in concentrated nitric acid or distilled ^water under the condition of 30-90 ℃ water-soluble heating and stirring to form an antimony nitrate solution; dissolved into their respective solutions;

3) Mix the antimony nitrate and zinc salt solutions thoroughly, add the tungstate solution drop by drop under constant stirring, after the dropwise addition is completed, continue to stir for 20-60 min, and filter the precipitate of tungstate at 40-100°C drying to prepare a precursor;

4) After grinding the precursor, put it into an alumina crucible, sinter in an air atmosphere at 400-900°C for 6-24 hours, cool to room temperature, take it out and grind it to obtain a Sb ³⁺ activated LED green phosphor.

Compared with prior art, the present invention has following beneficial effect:

1. The Sb ³⁺ activated tungstate LED green phosphor of the present invention not only has strong absorption in the ultraviolet region of 230nm-320nm, but also can absorb near-ultraviolet light of 320-370nm.

2. The emission spectrum of the tungstate LED green phosphor activated by Sb ³⁺ in the present invention is very wide, and it has strong emission in the blue-green light region of 450nm-600nm.

3. The tungstate LED green phosphor activated by Sb ³⁺ of the present invention has stable chemical properties and low synthesis temperature, which is beneficial to reduce energy consumption and product cost.

Description of drawings

Figure 1 is the excitation spectrum of a material sample Cd _0.999 WO ₄ :Sb ³⁺ _0.001 prepared according to the technique of Example 1 of the present invention. In Figure 1, the abscissa is the wavelength (nm), and the ordinate is the intensity (au).

Fig. 2 is the emission spectrum of the material sample Cd _0.999 WO ₄ :Sb ³⁺ _0.001 prepared according to the technique of Example 1 of the present invention. In Fig. 2, the abscissa is the wavelength (nm), and the ordinate is the intensity (au).

Fig. 3 is a chromaticity diagram of a material sample prepared according to the technique of Embodiment 1 of the present invention. In Figure 3, the abscissa is X color coordination, and the ordinate is Y color coordination.

Detailed ways

Example 1: Preparation of Cd _0.999 WO ₄ :Sb ³⁺ _0.001 LED green phosphor

1) Weigh 0.0029g antimony oxide (Sb ₂ O ₃ ), 6.1632g cadmium nitrate (Cd(NO ₃ ) ₂ ·4H ₂ O), 6.5974g sodium tungstate (Na ₂ WO ₄ ·2H ₂ O).

2) Use concentrated nitric acid to completely dissolve antimony oxide (Sb ₂ O ₃ ) to prepare antimony nitrate solution, and mix cadmium nitrate (Cd(NO ₃ ) ₂ 4H ₂ O) and sodium tungstate (Na ₂ WO ₄ 2H ₂ O) were dissolved in distilled water to prepare their own solutions.

3) Fully mix the antimony nitrate solution and the cadmium nitrate solution, add the sodium tungstate solution drop by drop under continuous stirring, and continue stirring for 20 minutes after the dropwise addition is completed, the tungstate precipitate will be formed by suction filtration, and dried at 60°C to prepare into a precursor.

4) After grinding the precursor, put it into an alumina crucible, sinter in air at 400 °C for 6 hours, take it out after cooling to room temperature, and grind it to obtain the Sb ³⁺ activated LED green phosphor.

Example 2: Preparation of Cd _0.998 WO ₄ : Sb ³⁺ _0.002 LED Green Phosphor Powder

1) Weigh 0.0058g antimony oxide (Sb ₂ O ₃ ), 6.1517g cadmium nitrate (Cd(NO ₃ ) ₂ ·4H ₂ O), 6.5974g sodium tungstate (Na ₂ WO ₄ ·2H ₂ O).

2) Use concentrated nitric acid to completely dissolve antimony oxide (Sb ₂ O ₃ ) to prepare antimony nitrate solution, and mix cadmium nitrate (Cd(NO ₃ ) ₂ 4H ₂ O) and sodium tungstate (Na ₂ WO ₄ 2H ₂ O) were dissolved in distilled water to obtain their respective solutions.

3) Fully mix the antimony nitrate solution and the cadmium nitrate solution, add the sodium tungstate solution drop by drop under continuous stirring, and continue stirring for 40 minutes after the dropwise addition is completed, the formed tungstate precipitate is sucked and filtered, and dried at 60°C to prepare into a precursor.

4) After grinding the precursor, put it into an alumina crucible, sinter it in the air at 500 °C for 6 hours, take it out after cooling to room temperature, and grind it to obtain the Sb ³⁺ activated LED green phosphor.

Example 3: Preparation of Cd _0.997 WO ₄ : Sb ³⁺ _0.003 LED green phosphor

1) Weigh 0.0087g antimony oxide (Sb ₂ O ₃ ), 6.1509g cadmium nitrate (Cd(NO ₃ ) ₂ ·4H ₂ O), 6.5974g sodium tungstate (Na ₂ WO ₄ ·2H ₂ O).

2) Use concentrated nitric acid to completely dissolve antimony oxide (Sb ₂ O ₃ ) to prepare antimony nitrate solution, and mix cadmium nitrate (Cd(NO ₃ ) ₂ 4H ₂ O) and sodium tungstate (Na ₂ WO ₄ 2H ₂ O) were dissolved in distilled water to obtain their respective solutions.

3) Fully mix the antimony nitrate solution and the cadmium nitrate solution, add the sodium tungstate solution drop by drop under continuous stirring, and continue stirring for 40 minutes after the dropwise addition is completed, the formed tungstate precipitate is sucked and filtered, and dried at 80°C to prepare into a precursor.

4) After grinding the precursor, put it into an alumina crucible, sinter in the air at 600 °C for 10 hours, cool to room temperature, take it out and grind it to obtain the Sb ³⁺ activated LED green phosphor.

Example 4: Preparation of Cd _0.996 WO ₄ :Sb ³⁺ _0.004 LED Green Phosphor Powder

1) Weigh 0.0117g antimony oxide (Sb ₂ O ₃ ), 6.1447g cadmium nitrate (Cd(NO ₃ ) ₂ ·4H ₂ O), 6.5974g sodium tungstate (Na ₂ WO ₄ ·2H ₂ O).

2) Use concentrated nitric acid to completely dissolve antimony oxide (Sb ₂ O ₃ ) to prepare antimony nitrate solution, and mix cadmium nitrate (Cd(NO ₃ ) ₂ 4H ₂ O) and sodium tungstate (Na ₂ WO ₄ 2H ₂ O) were dissolved in distilled water to obtain their respective solutions.

3) Fully mix the antimony nitrate solution and the cadmium nitrate solution, add the sodium tungstate solution drop by drop under constant stirring, and continue stirring for 60 minutes after the dropwise addition is completed, the tungstate precipitate will be formed by suction filtration, and dried at 100°C to prepare into a precursor.

4) After grinding the precursor, put it into an alumina crucible, sinter it in the air at 800 °C for 12 hours, take it out after cooling to room temperature and grind it to get the Sb ³⁺ activated LED green phosphor.

Example 5: Preparation of Cd _0.97 WO ₄ :Sb ³⁺ _0.03 LED Green Phosphor Powder

1) Weigh 0.0874g antimony oxide (Sb ₂ O ₃ ), 5.9843g cadmium nitrate (Cd(NO ₃ ) ₂ ·4H ₂ O), 6.5974g sodium tungstate (Na ₂ WO ₄ ·2H ₂ O).

2) Use concentrated nitric acid to completely dissolve antimony oxide (Sb ₂ O ₃ ) to prepare antimony nitrate solution, and mix cadmium nitrate (Cd(NO ₃ ) ₂ 4H ₂ O) and sodium tungstate (Na ₂ WO ₄ 2H ₂ O) were dissolved in distilled water to obtain their respective solutions.

3) Fully mix the antimony nitrate solution and the cadmium nitrate solution, add the sodium tungstate solution drop by drop under constant stirring, and continue stirring for 60 minutes after the dropwise addition is completed, the tungstate precipitate will be formed by suction filtration, and dried at 100°C to prepare into a precursor.

4) After grinding the precursor, put it into an alumina crucible, sinter it in the air at 800 °C for 24 hours, take it out after cooling to room temperature and grind it to get the Sb ³⁺ activated LED green phosphor.

Claims (9)

1. A Sb ³⁺ activated LED green phosphor, characterized in that: the phosphor is activated by trivalent antimony ions Sb ³⁺ , and the chemical expression is Cd _1-x WO ₄ :Sb ³⁺ _x , wherein, 0.001 ≦x≦0.03. 2. The Sb ³⁺ activated LED green phosphor according to claim 1, characterized in that: the matrix of the phosphor is antimony tungstate. 3. according to the described Sb ³⁺ activated LED green fluorescent powder of claim 1, it is characterized in that: the excitation wavelength of Cd _1-x WO ₄ :Sb ³⁺ _x phosphor powder is 220-380 nm, and the emission wavelength is 420-600 nm nm. 4. The Sb ³⁺ activated LED green phosphor according to claim 1, characterized in that: the phosphor can be used as a yellow-green phosphor for white LEDs. 5. according to the preparation method of the described a kind of Sb3 ⁺ activated LED green fluorescent powder of claim 1, it is characterized in that comprising the steps: 1) Weigh the raw materials according to the molar ratio of each element in the chemical expression Cd _1-x WO ₄ :Sb ³⁺ _x , wherein, 0.001≦x≦0.03; the raw materials contain antimony ions Sb ³⁺ and cadmium ions Cd ^{2 +} , compound of tungstate ion WO ₄ ^2- ; 2) Dissolve ^the compounds _containing antimony ions in concentrated nitric acid or distilled ^water under the condition of 30-90 ℃ water-soluble heating and stirring to form an antimony nitrate solution; dissolved into their respective solutions; 3) Fully mix the antimony nitrate and the solution containing cadmium ion Cd ²⁺ , add the tungstate solution drop by drop under continuous stirring, after the dropwise addition is completed, continue to stir for 20-60 min, and form a tungstate precipitate for suction filtration , dried at 40-100°C to prepare a precursor; 4) After grinding the precursor, put it into an alumina crucible, sinter in an air atmosphere at 400-900°C for 6-24 hours, cool to room temperature, take it out and grind it to obtain a Sb ³⁺ activated LED green phosphor. 6. according to the preparation method of the described a kind of Sb ³⁺ activated LED green fluorescent powder of claim 5, it is characterized in that: the described compound containing antimony ion Sb ³⁺ is the organic compound of antimony oxide, antimony nitrate and Bi ³⁺ One of the complexes, or any combination of them. 7. according to the preparation method of the described a kind of Sb ³⁺ activated LED green fluorescent powder of claim 5, it is characterized in that: the described compound containing cadmium ion Cd ²⁺ is the organic compound of cadmium oxide, bismuth nitrate and Cd ²⁺ One of the complexes, or any combination of them. 8 . The method for preparing a Sb ³⁺ -activated LED green phosphor according to claim 5 , wherein the compound containing zinc ions Zn ²⁺ is zinc nitrate. 9. According to the preparation method of a kind of Sb ³⁺ activated LED green fluorescent powder according to claim 5, it is characterized in that: the compound containing tungstate ion WO ₄ ^2- is any of potassium tungstate and sodium tungstate One or any combination of them.

Images