Co-doped alkaline earth aluminate long-afterglow luminescent material and preparation method thereof
By combining the sol-gel method with the doping modification method, the problems of high temperature and coarse grains in the high-temperature solid-phase method were solved, and a co-doped alkaline earth aluminate long-afterglow luminescent material with uniform composition, high purity and fine particles was prepared, thereby improving the afterglow performance.
Patent Information
- Application Number
- CN202510882538.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-27
- Publication Date
- 2025-10-10
AI Technical Summary
In the prior art, when synthesizing Eu2+-activated alkaline earth aluminate long-lasting luminescent materials by a high-temperature solid-phase method, there are problems such as high synthesis temperature, difficulty in obtaining single-phase compounds, and coarse grains, which lead to a decrease in luminescence brightness.
The sol-gel method is combined with the doping modification method to prepare a co-doped alkaline earth aluminate long-lasting luminescent material with uniform composition, high purity and fine particles by reacting an inorganic salt solution of co-doped strontium, europium and dysprosium with an aluminum isopropoxide solution.
The sintering temperature was lowered, and a long afterglow luminescent material with uniform composition, high purity and fine particles was prepared, thereby improving the afterglow performance.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of long afterglow luminescent material, in particular to a co-doped alkaline earth aluminate long afterglow luminescent material and a preparation method thereof. BACKGROUND
[0002] Long afterglow luminescent material is also called night phosphor. When the long afterglow luminescent material is excited by light, a part of the obtained light energy can be stored, and the light can be maintained for a long time after the light excitation stops. Therefore, the long afterglow luminescent material can be widely used as a passive light source in many aspects such as night emergency indication, instrument display, low-level lighting, home decoration, and national defense and military (such as night map) and the like. Among many afterglow materials, alkaline earth aluminate phosphor has excellent properties such as high afterglow brightness, long afterglow time, stable performance, no toxicity, and no pollution. At present, Eu 2+ The activated alkaline earth aluminate long afterglow luminescent material is very active in research. At present, the most studied method is high-temperature solid-phase method. However, the high-temperature solid-phase method has the defects of high synthesis temperature, difficulty in obtaining single-phase compound, and coarse crystal grains, and the luminous brightness will be greatly reduced after being ground. SUMMARY
[0003] The present application aims to provide a co-doped alkaline earth aluminate long afterglow luminescent material and a preparation method thereof, and solve the technical problems of high synthesis temperature, difficulty in obtaining single-phase compound, and coarse crystal grains in the prior art high-temperature solid-phase method.
[0004] The present application discloses a preparation method of a co-doped alkaline earth aluminate long afterglow luminescent material, comprising the following steps, S1. Dissolving aluminum isopropyl alcohol in anhydrous ethanol to form an aluminum isopropyl alcohol ethanol solution; S2. Dissolving an inorganic salt of strontium in anhydrous ethanol to form an A ethanol solution, dissolving an inorganic salt of europium in anhydrous ethanol to form a B ethanol solution, and dissolving an inorganic salt of dysprosium in anhydrous ethanol to form a C ethanol solution; S3. Adding the A ethanol solution, the B ethanol solution, and the C ethanol solution into the aluminum isopropyl alcohol ethanol solution according to the molar ratio of strontium + europium: aluminum + dysprosium being 4:14; S4. After adding nitric acid and water, the sol is left to stand to make it fully gelate; S5. After drying the gel obtained in step S4, heat treatment is performed in a reducing atmosphere to obtain the product.
[0005] Further, the inorganic salt of strontium is Sr(NO3)2 or SrCl2; the inorganic salt of europium is Eu(NO3)3·6H2O or EuCl2; and the inorganic salt of dysprosium is Dy(NO3)3·5H2O or DyCl3·6H2O.
[0006] Further, the strontium concentration in the A ethanol solution is 0.5-0.8 mol / L; the B ethanol solution concentration is 0.1-0.3 mol / L, and the C ethanol solution concentration is 0.1-0.3 mol / L.
[0007] Further, the aluminum isopropyl alcohol ethanol solution concentration is 0.5-1.2 mol / L.
[0008] Further, the standard addition amount of the nitric acid is H + :Al 3+ The molar ratio is 0.05-0.1.
[0009] Further, the standard addition amount of water in the step S3 is that the molar ratio of water:aluminum is 2-3.
[0010] Further, the drying temperature is 80-100 DEG C.
[0011] Further, the reducing atmosphere heat treatment temperature is 1000-1200 DEG C.
[0012] Further, the heating rate of the reducing atmosphere heat treatment is 5 DEG C / min, and the holding time is 1-2 h.
[0013] A hetero-alkaline earth aluminate long afterglow luminescent material has a molecular formula of: Sr （4-x） Eu x Al （14-y） Dy y O 25 , wherein the value of x is 0.01-0.05, and the value of y is 0.01-0.04.
[0014] Compared with the prior art, the present application has the beneficial effects of: 1. The present application uses a sol-gel method combined with a doping modification method to reduce the sintering temperature of the co-doped alkaline earth aluminate long afterglow luminescent material Sr4Al 14 O 25 :Eu 2+ ,Dy 3+ , and to prepare a long afterglow luminescent material with uniform composition, high purity, and fine particles, and to improve the afterglow performance. DETAILED DESCRIPTION
[0015] To make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application are described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments.
[0016] Example 1 The embodiment discloses a co-doped alkaline earth aluminate long afterglow luminescent material and a preparation method thereof, and comprises the following steps: Step 1: 0.5 mol of aluminum isopropoxide and 0.5 mol of Sr(NO3)2 are weighed and dissolved in 1L of anhydrous ethanol to form an anhydrous ethanol solution of aluminum isopropoxide and strontium nitrate with a concentration of 0.5 mol / L; 0.01 mol of Eu(NO3)3·6H2O and 0.01 mol of Dy(NO3)3·5H2O are weighed and dissolved in 0.1L of anhydrous ethanol to form an ethanol solution of europium nitrate and dysprosium nitrate with a total concentration of 0.1 mol / L.
[0017] Step 2: 279.8ml of the aluminum isopropoxide ethanol solution is taken in a beaker, and 79.8ml of the strontium nitrate ethanol solution, 1ml of the europium nitrate ethanol solution and 1ml of the dysprosium nitrate ethanol solution are added in the stirring process, 0.007 mol of nitric acid is added, and then 0.28 mol of water is added.
[0018] Step 3: the sol is placed for 24h to make it fully gelatinized, then dried in an oven at 80℃, and then placed in a hydrogen furnace to be heated to 1100℃ at a heating rate of 5℃ / min, and kept for 1h to obtain Sr 3.99 Eu 0.01 Al 13.99 Dy 0.01 O 25 powder; finally, afterglow performance testing is conducted.
[0019] Example 2 Step 1: 0.5 mol of aluminum isopropoxide and 0.5 mol of Sr(NO3)2 are weighed and dissolved in 1L of anhydrous ethanol to form an anhydrous ethanol solution of aluminum isopropoxide and strontium nitrate with a concentration of 0.5 mol / L; 0.01 mol of Eu(NO3)3·6H2O and 0.01 mol of Dy(NO3)3·5H2O are weighed and dissolved in 0.1L of anhydrous ethanol to form an ethanol solution of europium nitrate and dysprosium nitrate with a total concentration of 0.1 mol / L.
[0020] Step 2: 279.6ml of the aluminum isopropoxide ethanol solution is taken in a beaker, and 79.6ml of the strontium nitrate ethanol solution, 2ml of the europium nitrate ethanol solution and 2ml of the dysprosium nitrate ethanol solution are added in the stirring process, 0.007 mol of nitric acid is added, and then 0.28 mol of water is added.
[0021] Step 3: the sol is placed for 24h to make it fully gelatinized, then dried in an oven at 80℃, and then placed in a hydrogen furnace to be heated to 1100℃ at a heating rate of 5℃ / min, and kept for 1h to obtain Sr 3.98 Eu 0.02 Al 13.98 Dy 0.02 O25 Powder; finally, the afterglow performance test is carried out.
[0022] Example 3 Step 1: 0.5 mol of aluminum isopropoxide and 0.5 mol of Sr(NO3)2 are weighed into 1 L of anhydrous ethanol to form a 0.5 mol / L aluminum isopropoxide and strontium nitrate anhydrous ethanol solution; 0.01 mol of Eu(NO3)3·6H2O and 0.01 mol of Dy(NO3)3·5H2O are weighed into 0.1 L of anhydrous ethanol to form a 0.1 mol / L europium nitrate and dysprosium nitrate ethanol solution.
[0023] Step 2: 279.4 ml of the aluminum isopropoxide ethanol solution is taken in a beaker, and 79.4 ml of the strontium nitrate ethanol solution, 3 ml of the europium nitrate ethanol solution, and 3 ml of the dysprosium nitrate ethanol solution are added in the stirring process, 0.007 mol of nitric acid is added, and then 0.28 mol of water is added.
[0024] Step 3: The sol is left to stand for 24 h, and after being fully gelled, it is dried in an 80℃ oven, and then it is heated to 1100℃ at a heating rate of 5℃ / min in a hydrogen furnace, and is kept at this temperature for 1 h to obtain Sr 3.97 Eu 0.03 Al 13.97 Dy 0.03 O 25 Powder; finally, the afterglow performance test is carried out.
[0025] Example 4 Step 1: 0.5 mol of aluminum isopropoxide and 0.5 mol of Sr(NO3)2 are weighed into 1 L of anhydrous ethanol to form a 0.5 mol / L aluminum isopropoxide and strontium nitrate anhydrous ethanol solution; 0.01 mol of Eu(NO3)3·6H2O and 0.01 mol of Dy(NO3)3·5H2O are weighed into 0.1 L of anhydrous ethanol to form a 0.1 mol / L europium nitrate and dysprosium nitrate ethanol solution.
[0026] Step 2: 279.2 ml of the aluminum isopropoxide ethanol solution is taken in a beaker, and 79.2 ml of the strontium nitrate ethanol solution, 4 ml of the europium nitrate ethanol solution, and 4 ml of the dysprosium nitrate ethanol solution are added in the stirring process, 0.007 mol of nitric acid is added, and then 0.28 mol of water is added.
[0027] Step 3: The sol is left to stand for 24 h, and after being fully gelled, it is dried in an 80℃ oven, and then it is heated to 1200℃ at a heating rate of 5℃ / min in a hydrogen furnace, and is kept at this temperature for 1 h to obtain Sr 3.96 Eu 0.04 Al 13.96 Dy0.04 O 25 Powder; finally, the afterglow performance test is carried out.
[0028] Example 5 Step 1: 0.5 mol of aluminum isopropoxide and 0.5 mol of Sr(NO3)2 are weighed respectively and dissolved in 1 L of anhydrous ethanol to form an anhydrous ethanol solution of aluminum isopropoxide and strontium nitrate with a concentration of 0.5 mol / L; 0.01 mol of Eu(NO3)3·6H2O and 0.01 mol of Dy(NO3)3·5H2O are weighed respectively and dissolved in 0.1 L of anhydrous ethanol to form an ethanol solution of europium nitrate and dysprosium nitrate with a total concentration of 0.1 mol / L.
[0029] Step 2: 279.4 ml of the aluminum isopropoxide ethanol solution is taken in a beaker, and 79.6 ml of the strontium nitrate ethanol solution, 2 ml of the europium nitrate ethanol solution and 3 ml of the dysprosium nitrate ethanol solution are added in the process of stirring, 0.007 mol of nitric acid is added, and then 0.28 mol of water is added.
[0030] Step 3: the sol is placed for 24 h to make it fully gelatinized, then dried in an oven at 80℃, and then heated to 1200℃ at a heating rate of 5℃ / min in a hydrogen furnace, and kept for 1 h to obtain Sr 3.98 Eu 0.02 Al 13.97 Dy 0.03 O 25 Powder; finally, the afterglow performance test is carried out.
[0031] Comparative Example 1 The only change of this comparative example based on Example 1 is that the amount of the aluminum isopropoxide ethanol solution in Step 2 is 299.8 ml.
[0032] Comparative Example 2 The only change of this comparative example based on Example 1 is that the amount of water in Step 2 is 0.22 mol.
[0033] Comparative Example 3 The only change of this comparative example based on Example 1 is that the sintering temperature in Step 3 is 1300℃.
[0034] The key parameters and afterglow performance test results of the examples of the application are shown in Table 1.
[0035] Table 1
[0036] It can be seen from the test results that the center wavelength of all examples is 407 nm, indicating that the prepared sample is a pure phase and does not contain other structures; the afterglow time is greater than 20 hours, indicating that the afterglow performance of different doping amounts is very good. The amount of aluminum isopropyl alcohol ethanol solution in Comparative Example 1 is too much, and the change of the aluminum strontium ratio causes the center wavelength to shift. The amount of water and the sintering temperature in Comparative Examples 2 and 3 are outside the optimal range, resulting in reduced afterglow performance.
[0037] The above are the embodiments listed in the present embodiment, but the present embodiment is not limited to the above optional embodiments, and those skilled in the art can obtain other various embodiments by arbitrarily combining the above-mentioned modes with each other. The above specific embodiments should not be understood as limiting the protection scope of the present embodiment, and the protection scope of the present embodiment should be defined by the claims, and the specification can be used to explain the claims.
Claims
1. A method for preparing a co-doped alkaline earth aluminate long-lasting luminescent material, characterized in that: The following steps are included: S1. Dissolving aluminum isopropoxide in anhydrous ethanol to form an aluminum isopropoxide ethanol solution; S2. The inorganic salt of strontium is dissolved in anhydrous ethanol to form an ethanol solution A, the inorganic salt of europium is dissolved in anhydrous ethanol to form an ethanol solution B, and the inorganic salt of dysprosium is dissolved in anhydrous ethanol to form an ethanol solution C; S3. Strontium + europium: aluminum + dysprosium in a molar ratio of 4:14 A ethanol solution, B ethanol solution and C ethanol solution were added to aluminum isopropoxide ethanol solution; S4. After adding nitric acid and water, the sol is allowed to stand to fully gel; S5. The gel obtained in step S4 is dried and then heat-treated in a reducing atmosphere.
2. The method for preparing a co-doped alkaline earth aluminate long-lasting luminescent material according to claim 1, characterized in that: The inorganic salt of strontium is Sr(NO3)2 or SrCl2; the inorganic salt of europium is Eu(NO3)3·6H2O or EuCl2; and the inorganic salt of dysprosium is Dy(NO3)3·5H2O or DyCl3·6H2O.
3. The method for preparing a co-doped alkaline earth aluminate long-lasting luminescent material according to claim 1, characterized in that: The strontium concentration in the ethanol solution A is 0.5 mol / L-0.8 mol / L; the concentration in the ethanol solution B is 0.1 mol / L-0.3 mol / L; and the concentration in the ethanol solution C is 0.1 mol / L-0.3 mol / L.
4. The method for preparing a co-doped alkaline earth aluminate long-lasting luminescent material according to claim 1, characterized in that: The concentration of the aluminum isopropoxide ethanol solution is 0.5 mol / L-1.2 mol / L.
5. The method for preparing a co-doped alkaline earth aluminate long afterglow luminescent material according to claim 1, characterized in that: The addition amount of nitric acid is H + :Al 3+ The molar ratio is 0.05-0.
1.
6. The method for preparing a co-doped alkaline earth aluminate long afterglow luminescent material according to claim 1, characterized in that: The amount of water added in step S4 is such that the molar ratio of water to aluminum is 2-3.
7. The method for preparing a co-doped alkaline earth aluminate long afterglow luminescent material according to claim 1, characterized in that: The drying temperature is 80°C-100°C.
8. The method for preparing a co-doped alkaline earth aluminate long afterglow luminescent material according to claim 1, characterized in that: The reducing atmosphere heat treatment temperature is 1000°C-1200°C.
9. The method for preparing a co-doped alkaline earth aluminate long-lasting luminescent material according to claim 1, characterized in that: The heating rate of the reducing atmosphere heat treatment is 5°C / min, and the holding time is 1-2h.
10. A co-doped alkaline earth aluminate long afterglow luminescent material, characterized in that: Its molecular formula is: Sr （4-x） Eu x Al （14-y） Dy y O 25 , where x is between 0.01 and 0.05, and y is between 0.01 and 0.04.