CN100363459C - Red strontium aluminate long afterglow material and preparation method thereof - Google Patents

Abstract

The invention discloses a red strontium aluminate long afterglow material and a preparation method thereof. The material composition is Sr _2A Al _2B O ₈ :Eu ²⁺ , Dy ³⁺ , wherein A is 1.5-3 and B is 1.0; the method comprises a sol-gel method, and the steps are as follows: 1) adding water and urea to strontium nitrate, aluminum nitrate, europium nitrate and dysprosium nitrate according to a molar ratio of strontium nitrate: aluminum nitrate: europium nitrate: dysprosium nitrate: urea: water = 1.5-3:1:0.03:0.03:5:200, and keeping the temperature at 80-130°C for 7-20 hours to obtain a product; or, keeping the temperature at 80-130°C for 7-20 hours according to a molar ratio of water-soluble strontium salt: basic aluminum acetate: water-soluble europium salt: 1) mixing basic aluminum acetate with water at a molar ratio of water-soluble dysprosium salt: water = 1.5-3: 1: 0.03: 0.03: 200 to form a sol at 80-100°C, and then adding water-soluble strontium salt, europium salt and dysprosium salt to further form a sol; 2) first filtering the cooled product or dehydrating the sol into a gel, and then annealing it in a protective gas at 1200-1400°C for 2-4 hours to obtain a red strontium aluminate long afterglow material. It can be widely used in architectural decoration, military facilities, nano-marking and other fields.

Description

Red strontium aluminate long afterglow material and preparation method thereof

technical field

The invention relates to a long afterglow material and a preparation method thereof, in particular to a red strontium aluminate long afterglow material and a preparation method thereof.

Background technique

The aluminate luminescent body activated by rare earth elements such as europium is a new generation of photoluminescent materials. Fields such as consumer goods show broad application prospects. At present, people have made some attempts and efforts to obtain it, such as "a method for preparing a long-lasting luminescent material" disclosed in the Chinese invention patent application publication CN 1380373A published on November 20, 2002. It intends to provide a preparation method of strontium aluminate series light storage type long afterglow luminous powder material; the preparation method uses industrial aluminum as raw material, first makes it into alkoxide aluminum, and then according to the sol-gel characteristics of alkoxide Strontium carbonate, activator, sensitizer, etc. are coated with latex, and then dried and calcined. However, there are shortcomings in this preparation method. First, only long-lasting materials that emit blue and green light can be produced, but no long-lasting materials that emit red light can be prepared; secondly, the prepared long-lasting materials are powders. Or block, it needs to be pulverized, sieved and ground when it is used, which can easily affect the luminous intensity of the material and restrict its scope of application.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the deficiencies in the prior art, and provide a long afterglow material of strontium aluminate capable of emitting red light and a preparation method thereof.

The red strontium aluminate long afterglow material has the following chemical formula: Sr _2A Al _2B O ₈ :Eu ²⁺ , Dy ³⁺ , where A is 1.5-3 and B is 1.0.

The preparation method of red strontium aluminate long afterglow material comprises sol-gel method, especially it is finished in the following steps: (1), according to strontium nitrate: aluminum nitrate: europium nitrate: dysprosium nitrate: urea: water=1.5～ 3:1:0.03:0.03:5:200 molar ratio, first weigh strontium nitrate, aluminum nitrate, europium nitrate and dysprosium nitrate into the container according to the proportion, then add the corresponding amount of water and urea into it according to the proportion, stir After dissolving, keep it in a sealed state at 80-130°C for 7-20 hours to obtain the product, or, according to water-soluble strontium salt: basic aluminum acetate: water-soluble europium salt: water-soluble dysprosium salt: water=1.5-3:1: The molar ratio of 0.03:0.03:200, first weigh basic aluminum acetate, mix it with the corresponding amount of water in proportion to form a sol at 80-100°C, and then add the corresponding amount of water-soluble strontium in the sol Salt, water-soluble europium salt and water-soluble dysprosium salt to further form a sol; (2), first filter the cooled product or dehydrate the sol into a gel, and then place it in a protective gas at 1200-1400°C After annealing for 2 to 4 hours, a red strontium aluminate long afterglow material is obtained.

As a further improvement of the preparation method of red strontium aluminate long afterglow material, the water-soluble strontium salt is strontium nitrate or strontium acetate; the water-soluble europium salt is europium nitrate or europium acetate; the water-soluble dysprosium salt It is dysprosium nitrate or dysprosium acetate; the protective gas is a mixed gas composed of 93-98% argon and 2-7% hydrogen.

Compared with the beneficial effects of the prior art, firstly, the obtained red long afterglow material is analyzed by X-ray diffractometer, and it can be known from the obtained X-ray diffraction pattern that the chemical formula of the material is composed of Sr _2A Al _2B O ₈ : Eu ²⁺ , Dy ³⁺ , wherein, A is 1.5-3, and B is 1.0; second, use a full-featured steady-state/transient fluorescence spectrometer to detect long-lasting materials, and it can be seen from its spectrum , when the excitation light source is excited from ultraviolet to near infrared, the long afterglow material irradiated by the excitation light source will continue to emit light after the excitation light source is removed, and the spectral range of the afterglow light emitted by it is red light; third, in the long afterglow When the material emits red afterglow, it is tested with an afterglow curve measuring instrument. From the obtained afterglow curve, it can be seen that the time for red afterglow to reach the minimum resolution of the human eye is 0.32mcd/ ^m2 for more than 30 minutes Fourth, the preparation method is simple, easy to operate, low in cost, suitable for industrial production, and the finished product can be used directly without crushing, sieving and grinding; fifth, water-soluble strontium salt, europium salt and dysprosium salt Strontium nitrate or strontium acetate, europium nitrate or europium acetate, dysprosium nitrate or dysprosium acetate can be selected respectively, which not only makes the sources of raw materials more abundant, but also makes the preparation process easier and more flexible.

Description of drawings

The preferred modes of the present invention will be further described in detail below in conjunction with the accompanying drawings.

Fig. 1 is the X-ray diffraction diagram of the red long afterglow material measured by Phillips X Pert PRO type X-ray diffractometer CuK _α radiation to the long afterglow material, wherein the abscissa is the 2θ angle, and the ordinate is the intensity;

Figure 2 is the spectrogram obtained by using the FLS920 full-featured steady-state/transient fluorescence spectrometer of Edinburgh Instruments in the United Kingdom to detect long-lasting materials, where the abscissa is the wavelength, the ordinate is the intensity, and the dotted line in the spectrogram is the excitation. Spectrum, the solid line is the afterglow emission spectrum measured after the light excitation stops;

Figure 3 is the results obtained by using the ST-900 weak light photometer of the Beijing Normal University Optoelectronic Instrument Factory to measure the red long afterglow material after being irradiated with Hg lamp ultraviolet rays with a wavelength of 365nm and an intensity of 6mW/ ^cm2 for 10 minutes. Afterglow decay curve, where the abscissa is time and the ordinate is luminous intensity.

Detailed ways

Embodiment 1: The preparation steps are as follows, 1), put 1.5mol of strontium nitrate, 1.0mol of aluminum nitrate, 0.03mol of europium nitrate, and 0.03mol of dysprosium nitrate into the container, then add 200mol of water and 5.0mol of urea to it, after stirring and dissolving The product was obtained by keeping the temperature at 80° C. for 20 hours in a sealed state. Alternatively, mix 1.0 mol of basic aluminum acetate with 200 mol of water to form a sol at 100°C, then add 1.5 mol of strontium nitrate (or 1.5 mol of strontium acetate), 0.03 mol of europium nitrate (or 0.03 mol of europium acetate), Dysprosium nitrate 0.03mol (or dysprosium acetate 0.03mol) to further form a sol. 2), first filter the cooled product or dehydrate the sol into a gel, and then anneal it in a protective gas at 1200°C for 4 hours; wherein, the protective gas is 93% argon and 7% hydrogen Composed of mixed gas, the red strontium aluminate long afterglow material similar to that shown in Figure 1, the solid line in Figure 2 and the curve in Figure 3 is produced.

Example 2: The preparation steps are as follows, 1), put 1.8mol of strontium nitrate, 1.0mol of aluminum nitrate, 0.03mol of europium nitrate, and 0.03mol of dysprosium nitrate into the container, then add 200mol of water and 5.0mol of urea to it, stir and dissolve The product was obtained by keeping the temperature at 90° C. for 17 hours in a sealed state. Alternatively, mix 1.0 mol of basic aluminum acetate with 200 mol of water to form a sol at 95°C, and then add 1.8 mol of strontium nitrate (or 1.8 mol of strontium acetate), 0.03 mol of europium nitrate (or 0.03 mol of europium acetate), Dysprosium nitrate 0.03mol (or dysprosium acetate 0.03mol) to further form a sol. 2), first filter the cooled product or dehydrate the sol into a gel, and then anneal it in a protective gas at 1250°C for 3.5 hours; wherein, the protective gas is 94% argon and 6% hydrogen Composed of mixed gas, the red strontium aluminate long afterglow material similar to that shown in Figure 1, the solid line in Figure 2 and the curve in Figure 3 is produced.

Example 3: The preparation steps are as follows, 1), put 2.3mol of strontium nitrate, 1.0mol of aluminum nitrate, 0.03mol of europium nitrate, and 0.03mol of dysprosium nitrate into the container, then add 200mol of water and 5.0mol of urea, stir and dissolve The product was obtained by keeping the temperature at 100° C. for 13 hours in a sealed state. Alternatively, mix 1.0 mol of basic aluminum acetate with 200 mol of water to form a sol at 90°C, then add 2.3 mol of strontium nitrate (or 2.3 mol of strontium acetate), 0.03 mol of europium nitrate (or 0.03 mol of europium acetate), Dysprosium nitrate 0.03mol (or dysprosium acetate 0.03mol) to further form a sol. 2), first filter the cooled product or dehydrate the sol into a gel, and then anneal it in a protective gas at 1300°C for 3 hours; wherein, the protective gas is 96% argon and 4% hydrogen Composed of mixed gas, the red strontium aluminate long afterglow material similar to that shown in Figure 1, the solid line in Figure 2 and the curve in Figure 3 is produced.

Example 4: The preparation steps are as follows, 1), put 2.7mol of strontium nitrate, 1.0mol of aluminum nitrate, 0.03mol of europium nitrate, and 0.03mol of dysprosium nitrate into the container, then add 200mol of water and 5.0mol of urea, stir and dissolve The product was obtained by keeping the temperature at 115° C. for 10 hours in a sealed state. Alternatively, mix 1.0 mol of basic aluminum acetate with 200 mol of water to form a sol at 85°C, and then add 2.7 mol of strontium nitrate (or 2.7 mol of strontium acetate), 0.03 mol of europium nitrate (or 0.03 mol of europium acetate), Dysprosium nitrate 0.03mol (or dysprosium acetate 0.03mol) to further form a sol. 2), first filter the cooled product or dehydrate the sol into a gel, and then anneal it in a protective gas at 1350°C for 2.5 hours; wherein, the protective gas is 97% argon and 3% hydrogen Composed of mixed gas, the red strontium aluminate long afterglow material similar to that shown in Figure 1, the solid line in Figure 2 and the curve in Figure 3 is produced.

Example 5: The preparation steps are as follows, 1), put 3.0mol of strontium nitrate, 1.0mol of aluminum nitrate, 0.03mol of europium nitrate, and 0.03mol of dysprosium nitrate into the container, then add 200mol of water and 5.0mol of urea, stir and dissolve The product was obtained by keeping the temperature at 130° C. for 7 hours in a sealed state. Alternatively, mix 1.0 mol of basic aluminum acetate with 200 mol of water to form a sol at 80°C, then add 3.0 mol of strontium nitrate (or 3.0 mol of strontium acetate), 0.03 mol of europium nitrate (or 0.03 mol of europium acetate), Dysprosium nitrate 0.03mol (or dysprosium acetate 0.03mol) to further form a sol. 2), first filter the cooled product or dehydrate the sol into a gel, and then anneal it in a protective gas at 1400°C for 2 hours; wherein, the protective gas is 98% argon and 2% hydrogen The mixed gas formed produces the red strontium aluminate long afterglow material as shown by the solid line in Fig. 1 and Fig. 2 and the curve in Fig. 3 .

Apparently, those skilled in the art can make various changes and modifications to the red strontium aluminate long afterglow material and the preparation method thereof without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (3)

1. a red strontium aluminate long-afterglow material is characterized in that having following chemical formula and forms: Sr _2AAl _2BO ₈: Eu ²⁺, Dy ³⁺, wherein, A is 1.5～3, B is 1.0.

2. the preparation method of red strontium aluminate long-afterglow material according to claim 1 comprises sol-gel method, it is characterized in that finishing according to the following steps:

2.1, according to strontium nitrate: aluminum nitrate: europium nitrate: Dysprosium trinitrate: urea: water=1.5～3: 1: 0.03: 0.03: 5: 200 molar ratio, earlier take by weighing strontium nitrate, aluminum nitrate, europium nitrate and Dysprosium trinitrate to scale and put into container, again to the water and the urea that wherein add corresponding amount to scale, under sealed state, obtained product in 7～20 hours after the stirring and dissolving in 80～130 ℃ of insulations

Perhaps, according to strontium nitrate or strontium acetate: eston: europium nitrate or acetic acid europium: Dysprosium trinitrate or acetic acid dysprosium: water=1.5～3: 1: 0.03: 0.03: 200 molar ratio, take by weighing eston earlier, it is mixed the back form colloidal sols with the water of corresponding amount to scale down in 80～100 ℃, in colloidal sol, add the strontium nitrate of corresponding amount to scale or strontium acetate, europium nitrate or acetic acid europium and Dysprosium trinitrate or acetic acid dysprosium again and further form colloidal sol;

2.2, earlier cooled product is filtered or colloidal sol is dehydrated into gel, with annealing 2～4 hours in its protective gas under 1200～1400 ℃, make red strontium aluminate long-afterglow material again.

3. the preparation method of red strontium aluminate long-afterglow material according to claim 2 is characterized in that protective gas is the mixed gas that is made of 93～98% argon gas and 2～7% hydrogen.

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