CN110452697A - A luminescent material capable of emitting both red light and blue-green light and a preparation method thereof - Google Patents

Abstract

The invention belongs to the technical field of luminescent material preparation, and in particular relates to a luminescent material capable of emitting both red light and blue-green light and a preparation method thereof. The chemical composition of the luminescent material is xSm ₂ O ₃ ·(1-1.5x)ZrO ₂ ·(1-2.5y)SiO ₂ ·yP ₂ O ₅ (x=0.002~0.12; y=0.001~0.1). The preparation method adopts a preparation process of nanometer material coating sol-gel combined with high-temperature calcination. After being irradiated by light, the luminescent material can emit bright red light, and after the light is stopped, it can be observed to emit blue-green light in the dark for more than 12 hours. The fluorescence spectrum shows that the emission peak band of the luminescent material is very broad. The material of the invention has stable chemical properties and excellent luminous performance, and can be developed as a fluorescent material or as a light-storage ceramic material or a material with both fluorescence and light-storage functions.

Description

A luminescent material capable of emitting both red light and blue-green light and a preparation method thereof

technical field

The invention relates to a luminescent ceramic material and a preparation method thereof, in particular to a luminescent material capable of emitting both red light and blue-green light and a preparation method thereof, belonging to the technical field of luminescent material preparation.

Background technique

Luminescent material, also known as long afterglow luminescent material, is a special photoluminescent material that can integrate energy storage and energy release. It is considered to be a new type of lighting and display material that is pollution-free, environmentally friendly and energy-saving, and is deeply loved by people. focus on. It is more and more widely used in the fields of transportation, military, security, electrical appliances, construction, and information storage. People's research on light storage materials began in the early 20th century. At that time, Mrs. Curie discovered that the element radium had a long afterglow phenomenon. It was used as a lighting material, but it was stopped because of the radioactivity of the element radium. At present, common light storage materials mainly include sulfide, aluminate, silicate, phosphate and so on. Silicate-based long-lasting luminescent materials have the advantages of stable system, low-cost and easy-to-obtain materials, and low sintering temperature, so they are often used as the matrix of long-lasting luminescent materials. Chinese invention patent CN104073255A discloses a preparation method and application of Eu ³⁺ doped A ₂ ZrSi ₂ O ₇ (where A is an alkali metal) blue-green zirconium silicate fluorescent powder; Chinese invention patent CN107129801A discloses a Li ⁺ The method of co-doping to improve the long afterglow characteristics of silicate phosphors, its chemical expression is Sr ₂ MgSiO ₇ :xEu ²⁺ yDy ³⁺ zLi ⁺ , the doping of Li ⁺ increases the oxygen vacancies, making the trapped electrons increase, thereby increasing the persistence time. For long-lasting luminescent materials, it is very important to choose a suitable matrix. The luminescent material of the present invention is x(Sm ₂ O ₃ )·(1-1.5x)ZrO ₂ ·(1-2.5y)SiO ₂ ·yP ₂ O ₅ (x=0.002~0.12; y=0.001~0.1), expressed as Sm ³⁺ and Zr ⁴⁺ are common luminescent centers, which can emit both red light and blue-green light, with stable chemical properties and excellent luminescent performance. Appropriate doping of P ⁵⁺ and Sm ³⁺ , using NaF as a mineralizer and high-temperature calcination in a reducing atmosphere are beneficial to improving the luminescent properties of the material and improving the stability and crystallization properties of the material.

Contents of the invention

The object of the present invention is to provide a luminescent material capable of emitting both red light and blue-green light and a preparation method thereof.

To achieve the above object, the present invention adopts the following technical solutions:

A luminescent material capable of emitting both red light and blue-green light, the chemical composition of which is xSm ₂ O ₃ ·(1-1.5x)ZrO ₂ ·(1-2.5y)SiO ₂ ·yP ₂ O ₅ (x=0.002 ~0.12; y= 0.001~0.1).

The preparation method comprises the following steps:

1) Weigh the raw materials ZrO ₂ , tetraethyl orthosilicate, (NH ₄ ) ₂ HPO ₄ , Sm ₂ O ₃ respectively according to the stoichiometric ratio, and weigh them according to xSm ₂ O ₃ ·(1-1.5x)ZrO ₂ ·(1 -2.5y) SiO ₂ ·yP ₂ O ₅ (x=0.002~0.12; y=0.001~0.1) molar percentage is 0.3-1.0 mol%, and the mineralizer boric acid is weighed;

2) Mix ethyl orthosilicate and absolute ethanol at a volume ratio of 1:1-5, add appropriate water to dilute after mixing, and form a clear solution;

3) Dissolve the water-soluble (NH ₄ ) ₂ HPO ₄ raw material in step 1) in water to make a concentration of 2M for later use; slowly add concentrated nitric acid to the Sm ₂ O ₃ powder and stir while adding Until it is completely dissolved, add distilled water to dilute 3-5 times, then add flux agent boric acid to make a clear solution for later use;

4) Mix the nano-ZrO ₂ weighed in the above step 1), the clear solution of step 2), the (NH ₄ ) ₂ HPO ₄ solution of step 3), and the clear solution prepared by Sm ₂ O ₃ and boric acid, and adjust the pH The value is between 1-6. Stir continuously in a water bath at 60-95°C, take it out after forming a gel, and dry it in a drying oven at 100-120°C for 4-8 hours;

5) Put the dry gel in step 4) into a crucible and put it into a high-temperature furnace, and calcinate it at 1100-1300°C for 2-4 hours in a weak reducing atmosphere (H ₂ /N ₂ mixed gas or CO). hours, a luminescent material x(Sm ₂ O ₃ )·(1-1.5x)ZrO ₂ ·(1-2.5y)SiO ₂ ·yP ₂ O ₅ (x =0.002~0.12; y= 0.001~0.1).

Significant advantage of the present invention is:

After the material prepared by the present invention is irradiated by light, the luminescent material can emit bright red light, and after the light is stopped, it can be observed in the dark for more than 12 hours to emit blue-green light, and the fluorescence spectrum shows that the emission peak band of the luminescent material is very Wide, it has both the characteristic emission of Zr ⁴⁺ and the characteristic emission of Sm ³⁺ , and Sm ³⁺ and Zr ⁴⁺ serve as the common luminescent center. The introduction of a small amount of P ^{5 +} and Sm ³⁺ doping plays a significant role in improving the luminescence performance of the material. The material prepared by the invention has stable chemical properties and excellent luminous performance, and can be developed as a fluorescent material or as a light-storage ceramic material or a material with both fluorescence and light-storage functions.

Description of drawings

Figure 1: X-ray diffraction patterns of 0.02Sm ₂ O ₃ ·0.97ZrO ₂ ·0.875SiO ₂ ·0.05P ₂ O ₅ and 0.02Sm ₂ O ₃ ·0.97ZrO ₂ ·SiO ₂ ;

Figure 2: Fluorescence spectrum of 0.02Sm ₂ O ₃ ·0.97ZrO ₂ ·0.875SiO ₂ ·0.05P ₂ O ₅ ;

Figure 3: Afterglow decay curves of 0.02Sm ₂ O ₃ ·0.97ZrO ₂ ·0.875SiO ₂ ·0.05P ₂ O ₅ and ZrO ₂ ·SiO ₂ ;

Figure 4: Thermal release curves of 0.02Sm ₂ O ₃ ·0.97ZrO ₂ ·0.875SiO ₂ ·0.05P ₂ O ₅ and ZrO ₂ ·SiO ₂ .

Detailed ways

In order to further disclose rather than limit the present invention, the present invention will be further described in detail below in conjunction with examples.

Example 1

A luminescent material capable of emitting both red light and blue-green light. Its chemical composition is 0.01Sm ₂ O ₃ ·0.985ZrO ₂ ·0.75SiO ₂ ·0.1P ₂ O ₅ .

The preparation method comprises the following steps:

1) Weigh the raw materials ZrO ₂ , tetraethyl orthosilicate, (NH ₄ ) ₂ HPO ₄ , Sm ₂ O ₃ respectively according to the stoichiometric ratio, and weigh them according to 0.01Sm ₂ O ₃ 0.985ZrO ₂ 0.75SiO ₂ 0.1P _The molar percentage of ₂ O is 0.3 mol% and takes mineralizer boric acid;

2) Mix ethyl orthosilicate and absolute ethanol at a volume ratio of 1:5, add appropriate water to dilute after mixing, and form a clear solution;

3) Dissolve the water-soluble (NH ₄ ) ₂ HPO ₄ raw material in step 1) in water to make a concentration of 2M for later use; slowly add concentrated nitric acid to the Sm ₂ O ₃ powder and stir while adding Until it is completely dissolved, add distilled water to dilute 3-5 times, then add flux agent boric acid to make a clear solution for later use;

4) Mix the nano-ZrO ₂ weighed in the above step 1), the clear solution of step 2), the (NH ₄ ) ₂ HPO ₄ solution of step 3), and the clear solution prepared by Sm ₂ O ₃ and boric acid, and adjust the pH The value is 6. Stir continuously in a water bath at 60°C, take it out after forming a gel, and dry it in a drying oven at 100°C for 4 hours;

5) Put the xerogel in step 4) into a crucible and put it into a high-temperature furnace, and calcinate it at 1100°C for 4 hours in a weak reducing atmosphere (H ₂ /N ₂ mixed gas or CO) to obtain A luminescent material capable of emitting both red light and blue-green light: 0.01Sm ₂ O ₃ ·0.985ZrO ₂ ·0.75SiO ₂ ·0.1P ₂ O ₅ . After being irradiated by light, the luminescent material can emit bright red light, and after the light is stopped, it can be observed to emit blue-green light in the dark for more than 6 hours.

Example 2

A luminescent material capable of emitting both red light and blue-green light, its chemical composition is 0.1Sm ₂ O ₃ ·0.85ZrO ₂ ·0.975SiO ₂ ·0.01P ₂ O ₅ .

The preparation method comprises the following steps:

1) Weigh the raw materials ZrO ₂ , tetraethyl orthosilicate, (NH ₄ ) ₂ HPO ₄ , and Sm ₂ O ₃ according to the stoichiometric ratio, and weigh them according to 0.1Sm ₂ O ₃ 0.85ZrO ₂ 0.975SiO ₂ 0.01P _The molar percentage of ₂ O is 1.0 mol% and takes mineralizer boric acid;

2) Mix tetraethyl orthosilicate and absolute ethanol at a volume ratio of 1:4, add appropriate water to dilute after mixing, and form a clear solution;

3) Dissolve the water-soluble (NH ₄ ) ₂ HPO ₄ raw material in step 1) in water to make a concentration of 2M for later use; slowly add concentrated nitric acid to the Sm ₂ O ₃ powder and stir while adding Until it is completely dissolved, add distilled water to dilute it 5 times, then add the fluxing agent boric acid to make a clear solution for later use;

4) Mix the nano-ZrO ₂ weighed in the above step 1), the clear solution of step 2), the (NH ₄ ) ₂ HPO ₄ solution of step 3), and the clear solution prepared by Sm ₂ O ₃ and boric acid, and adjust the pH The value is between 3, stir continuously in a water bath at 80°C, take it out after forming a gel, and dry it in a drying oven at 110°C for 6 hours;

5) Put the dry gel in step 4) into a crucible and put it into a high-temperature furnace, and calcinate it at 1300°C for 2 hours in a weak reducing atmosphere (H ₂ /N ₂ mixed gas or CO) to obtain A luminescent material capable of emitting both red light and blue-green light: 0.1Sm ₂ O ₃ ·0.85ZrO ₂ ·0.975SiO ₂ ·0.01P ₂ O ₅ . After being irradiated by light, the luminescent material can emit bright red light, and after the light is stopped, it can be observed to emit blue-green light in the dark for more than 9 hours.

Example 3

A luminescent material capable of emitting both red light and blue-green light, the chemical composition of which is 0.02Sm ₂ O ₃ ·0.97ZrO ₂ ·0.875SiO ₂ ·0.05P ₂ O ₅ .

The preparation method comprises the following steps:

1) Weigh the raw materials ZrO ₂ , tetraethyl orthosilicate, (NH ₄ ) ₂ HPO ₄ , Sm ₂ O ₃ respectively according to the stoichiometric ratio, and weigh them according to 0.02Sm ₂ O ₃ 0.97ZrO ₂ 0.875SiO ₂ 0.05P _The molar percentage of ₂ O is 1.0 mol% and takes mineralizer boric acid;

2) Mix ethyl orthosilicate and absolute ethanol at a volume ratio of 1:5, add appropriate water to dilute after mixing, and form a clear solution;

3) Dissolve the water-soluble (NH ₄ ) ₂ HPO ₄ raw material in step 1) in water to make a concentration of 2M for later use; slowly add concentrated nitric acid to the Sm ₂ O ₃ powder and stir while adding Until it is completely dissolved, add distilled water to dilute 3-5 times, then add flux agent boric acid to make a clear solution for later use;

4) Mix the nano-ZrO ₂ weighed in the above step 1), the clear solution of step 2), the (NH ₄ ) ₂ HPO ₄ solution of step 3), and the clear solution prepared by Sm ₂ O ₃ and boric acid, and adjust the pH The value is 5. Stir continuously in a water bath at 95°C, take it out after forming a gel, and dry it in a drying oven at 120°C for 6 hours;

5) Put the dry gel in step 4) into a crucible and put it into a high-temperature furnace, and calcinate it at 1200°C for 4 hours in a weak reducing atmosphere (H ₂ /N ₂ mixed gas or CO) to obtain A luminescent material capable of emitting both red light and blue-green light: 0.02Sm ₂ O ₃ ·0.97ZrO ₂ ·0.875SiO ₂ ·0.05P ₂ O ₅ . After being irradiated by light, the luminescent material can emit bright red light, and after the light is stopped, it can be observed to emit blue-green light in the dark for more than 12 hours.

Fig. 1 is an X-ray diffraction diagram of 0.02Sm ₂ O ₃ ·0.97ZrO ₂ ·0.875SiO ₂ ·0.05P ₂ O ₅ and 0.02Sm ₂ O ₃ ·0.97ZrO ₂ ·SiO ₂ . It was characterized by X-ray powder diffractometer, and the results showed that the XRD spectrum of the long-lasting luminescent material was basically consistent with the standard spectrum PDF#06-0266. After being irradiated by light, the luminescent material can emit bright red light, and after the light is stopped, blue-green light can be continuously observed in the dark for more than 12 hours. Figure 2 is the fluorescence spectrum of 0.02Sm ₂ O ₃ ·0.97ZrO ₂ ·0.875SiO ₂ ·0.05P ₂ O ₅ . The fluorescence spectrum in the figure shows that the emission peak band of the luminescent material is very wide, among which 453, 466, and 481 nm belong to the characteristic emission peaks of Zr ⁴⁺ , which belong to the blue light category; while the emission peak of ⁵⁶⁷ nm belongs to the ⁶ H _{5/ 2} - ⁴ G _5/2 energy level transition, located in the green light range; 603 nm and 615 nm emission peaks are attributed to the ⁶ H _7/2 - ⁴ G _5/2 energy level transition of Sm ³⁺ , while 650 nm and 660 nm The emission peaks belong to the ⁶ H _9/2 - ⁴ G _5/2 energy level transition of Sm ³⁺ , which belong to the red light category.

Fig. 3 is the afterglow decay curves of 0.02Sm ₂ O ₃ ·0.97ZrO ₂ ·0.875SiO ₂ ·0.05P ₂ O ₅ and ZrO ₂ ·SiO ₂ . It can be seen from the figure that the introduction of doping ions Sm ³⁺ and P ⁵⁺ can significantly improve the afterglow performance of the material. Fig. 4 shows the thermal release curves of 0.02Sm ₂ O ₃ ·0.97ZrO ₂ ·0.875SiO ₂ ·0.05P ₂ O ₅ and ZrO ₂ ·SiO ₂ . It can be seen from the figure that the introduction of doping ions Sm ³⁺ and P ⁵⁺ can significantly improve the low-temperature defect concentration of the material, which is beneficial to the improvement of the luminescent performance of the material.

The above descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope of the present invention.

Claims (5)

1. A luminescent material capable of emitting both red light and blue-green light, characterized in that: the chemical composition of the luminescent material is xSm ₂ O ₃ ·(1-1.5x)ZrO ₂ ·(1-2.5y)SiO ₂ ·yP ₂ O ₅ , x=0.002~0.12, y=0.001~0.1. 2. A method for preparing a luminescent material capable of emitting both red light and blue-green light as claimed in claim 1, characterized in that: comprising the following steps: 1) Weigh the raw materials ZrO ₂ , tetraethyl orthosilicate, (NH ₄ ) ₂ HPO ₄ , Sm ₂ O ₃ respectively according to the stoichiometric ratio, and weigh them according to xSm ₂ O ₃ ·(1-1.5x)ZrO ₂ ·(1 -2.5y) The molar percentage of SiO ₂ ·yP ₂ O ₅ is 0.3-1.0 mol% and the mineralizer boric acid is weighed; 2) Mix ethyl orthosilicate and absolute ethanol at a volume ratio of 1:1-5, add appropriate water to dilute after mixing, and form a clear solution; 3) Dissolve the water-soluble (NH ₄ ) ₂ HPO ₄ raw material in step 1) in water to make a concentration of 2M for later use; slowly add concentrated nitric acid to the Sm ₂ O ₃ powder and stir while adding Until it is completely dissolved, add distilled water to dilute 3-5 times, then add flux agent boric acid to make a clear solution for later use; 4) Mix the nano-ZrO ₂ weighed in the above step 1), the clear solution of step 2), the (NH ₄ ) ₂ HPO ₄ solution of step 3), and the clear solution prepared by Sm ₂ O ₃ and boric acid, and adjust the pH The value is between 1-6. Stir continuously in a water bath at 60-95°C. After forming a gel, take it out and dry it in a drying oven; 5) Put the xerogel in step 4) into a crucible and put it into a high-temperature furnace, and calcinate it in a weak reducing atmosphere to prepare the luminescent material capable of emitting both red light and blue-green light. 3 . The preparation method according to claim 2 , wherein the drying in step (4) is specifically drying at 100-120° C. for 4-8 hours. 4 . 4. The preparation method according to claim 2, characterized in that the weak reducing atmosphere in step (5) is a mixed gas of H ₂ and N ₂ , or CO gas. 5 . The preparation method according to claim 2 , wherein the calcination in step (5) is specifically calcination at 1100-1300° C. for 2-4 hours.