An orange-red sodium niobate-calcium titanate stress luminescence material and a preparation method thereof

Abstract

This invention provides an orange-red sodium niobate-calcium titanate stress luminescent material and its preparation method. The material is composed of a mixture of phosphor and resin, wherein the phosphor has the chemical formula: Na... 0.985‑x Ca x Pr 0.005 Nb 1‑x Ti x O3, where x represents the mole fraction, 0.01 ≤ x ≤ 0.09. Its preparation method is as follows: 1) Mix Na2CO3 and Pr6O... 11 The process involves: 1) Using CaCO3, TiO2, and Nb2O5 as raw materials, mixing them according to their chemical formulas, ball milling, drying, first firing, first grinding, second firing, and second grinding to obtain phosphor; 2) Mixing epoxy resin and alicyclic amine according to a specific ratio to obtain a resin mixture; 3) Allowing the phosphor and resin mixture to stand, drying, and demolding to obtain the stress-luminescent material. The stress-luminescent material prepared by this invention exhibits excellent luminescent properties.

Description

Technical Field

[0001] This invention relates to the field of inorganic luminescent materials technology, specifically to an orange-red sodium niobate-calcium titanate stress luminescent material and its preparation method. Background Technology

[0002] Photoluminescence refers to the phenomenon where a solid material emits light by irradiating it with an external light source, thereby exciting electrons within the material. Stress luminescence, on the other hand, refers to the luminescence induced by mechanical stimuli such as friction and compression in solid materials. Currently, stress-luminescent materials based on refined grinding and compression conditions are widely used to monitor the stress distribution of structural objects, thereby manufacturing high-sensitivity sensors, as well as flexible display technologies and optical devices.

[0003] Currently available stress-luminescent materials, such as ZnS:Cu 2+ Research and Application of Mechanical Properties of Stress-Luminescent Thin Films (Journal of Yancheng Institute of Technology (Natural Science Edition), 2023, 36(04):64-69), and also "K x Na 1-x NbO3:Pr 3+ The stress-luminescent material disclosed in "Photoluminescence and Stress-Luminescence Properties of Ferroelectrics" (Acta Physica Sinica, 2022, 71(16):167801) produces the harmful gas sulfur dioxide, which not only poses a threat to the environment and human health, but also affects the service life of the material itself. For example, SrAl2O4:Eu emits green light... 2+ ,Dy 3+ However, it has the drawback of being unstable when exposed to water and undergoing a hydrolysis reaction.

[0004] Sodium niobate-based stress-luminescent materials can emit visible or ultraviolet light when subjected to stress, but the luminescence performance of sodium niobate-based stress-luminescent materials currently under study is poor. Summary of the Invention

[0005] This invention provides a high-strength, orange-red sodium niobate-calcium titanate stress luminescent material and its preparation method.

[0006] The technical solution provided by this invention is an orange-red sodium niobate-calcium titanate stress luminescent material, which is composed of a mixture of phosphor and resin. The chemical formula of the phosphor is: Na 0.985-x Ca x Pr 0.005 Nb 1-x Ti x O3, where x represents the mole fraction, 0.01 ≤ x ≤ 0.09;

[0007] The resin mixture is composed of epoxy resin and alicyclic amine, with a mass ratio of 3 to 10:1.

[0008] The weight ratio of the phosphor to the resin mixture is 1:1 to 5.

[0009] The phosphor has an orthorhombic phase structure, Ca 2+ and Pr 3+ Replace Na + The site enters the crystal lattice and has photoluminescence properties. Under the condition of excitation wavelength of 290nm, it emits orange-red light with a wavelength of 580-650nm.

[0010] The stress-luminescent material of the present invention has good stress-luminescent properties under friction conditions, emitting orange-red light with an emission wavelength of 580-650nm and an emission center position of 611nm.

[0011] As a preferred value, 0.03≤x≤0.05.

[0012] More preferably, x = 0.03.

[0013] This invention also provides a method for preparing an orange-red sodium niobate-calcium titanate stress-luminescent material, comprising the following steps:

[0014] 1) Add Na2CO3 and Pr6O 11 Using CaCO3, TiO2, and Nb2O5 as raw materials, according to the chemical formula Na 0.985-x Ca x Pr 0.005 Nb 1- x Ti x O3 is used as an ingredient, and the mixture is ball-milled with anhydrous ethanol as a solvent. After drying, it is calcined for the first time, ground for the first time, calcined for the second time, and ground for the second time to obtain the phosphor.

[0015] 2) Mix epoxy resin and alicyclic amine according to the specified ratio to obtain a resin mixture;

[0016] 3) Pour the formulated amount of phosphor and resin mixture into the mold in sequence, let it stand, dry it, and demold it to obtain the stress luminescent material.

[0017] In step 1), the ball milling is carried out at a ball milling speed of 100-300 r / min for 2-12 hours.

[0018] In step 1), the first firing involves heating to 700-900°C at a rate of 3-10°C / min and holding at that temperature for 3-9 hours.

[0019] The second firing is carried out at 1050-1200℃ for 2-6 hours.

[0020] The first and second grinding times were both 30 to 60 minutes.

[0021] The present invention has the following beneficial effects:

[0022] 1. This invention uses ball milling and high-temperature solid-phase synthesis to prepare samples, which greatly reduces the particle size, making it easier to mix the materials evenly. The high-temperature solid-phase synthesis method has the advantages of being simple to operate, low cost, high product purity, and good particle characteristics, and has therefore been widely used in the field of inorganic material preparation.

[0023] 2. The present invention adds praseodymium and calcium titanate to sodium niobate, and the resulting composite material has good stress luminescence performance, emitting orange-red light with an emission wavelength of 580-650nm. Attached Figure Description

[0024] Figure 1 The XRD patterns of the phosphors in Examples 1-5 and Control Example 1 are shown.

[0025] Figure 2 The PLE and PL plots are normalized to NPN-0.01CT in Example 1;

[0026] Figure 3 The photoluminescence spectrum of the phosphor in Example 1;

[0027] Figure 4 The triboluminescence spectrum of the stress-luminescent material in Example 1;

[0028] Figure 5 The photoluminescence spectrum of the phosphor in Example 2;

[0029] Figure 6 The triboluminescence spectrum of the stress-luminescent material in Example 2;

[0030] Figure 7 The photoluminescence spectrum of the phosphor in Example 3;

[0031] Figure 8 The triboluminescence spectrum of the stress-luminescent material in Example 3;

[0032] Figure 9 The photoluminescence spectrum of the phosphor in Example 4;

[0033] Figure 10 The triboluminescence spectrum of the stress-luminescent material in Example 4;

[0034] Figure 11 The photoluminescence spectrum of the phosphor in Example 5;

[0035] Figure 12 The triboluminescence spectrum of the stress-luminescent material in Example 5;

[0036] Figure 13 The photoluminescence spectrum of the phosphor in Comparative Example 1 is shown below.

[0037] Figure 14 The triboluminescence spectrum of the stress-luminescent material in Comparative Example 1 is shown. Detailed Implementation

[0038] The present invention will be further described below with reference to the embodiments, but the present invention is not limited to these embodiments.

[0039] Example 1

[0040] 1) Add Na2CO3 and Pr6O 11 Using CaCO3, TiO2, and Nb2O5 as raw materials, according to the chemical formula Na 0.975 Ca 0.01 Pr 0.005 Nb 0.99 Ti 0.01 O3 is used in the preparation, namely: 5.1670g Na2CO3, 0.0851g Pr6O 11 0.1001g CaCO3, 0.0799g TiO2, and 13.1576g Nb2O5 were placed in an agate ball mill jar, and 80ml of anhydrous ethanol was added. The mixture was ball-milled at 100r / min for 2 hours. After removal, it was dried at 80℃. It was then sintered in an oven, heated to 700℃ at a rate of 3℃ / min and held for 3 hours. After cooling to room temperature, it was removed and ground for 30 minutes. It was then sintered again in an oven at 1050℃ for 2 hours and ground for 30 minutes to obtain the phosphor (abbreviated as NPN-0.01CT).

[0041] 2) Mix epoxy resin and alicyclic amine at a mass ratio of 3:1 until no bubbles are generated to obtain a resin mixture. Prepare the phosphor and resin mixture by mixing them at a mass ratio of 1:1.

[0042] 3) Apply petroleum jelly to the inner surface of the polytetrafluoroethylene mold, pour the phosphor prepared in step 2) into the bottom of the mold and spread it evenly, then pour the resin mixture prepared in step 2) into the mold, let it stand in air for 5 minutes, then transfer it to an oven and dry it at 60°C for 4 hours. Take it out, demold it, and you will get the stress luminescent material.

[0043] To verify the phase structure of NPN-0.01CT, XRD tests were performed. The test results are as follows: Figure 1 As shown, the diffraction peak of NPN-0.01CT is consistent with the standard peak of sodium niobate, exhibiting a typical perovskite structure. The crystal structure is an orthorhombic perovskite structure. The doping of CaTiO3 did not affect the synthesis of the crystal phase, and no second phase or other impurity phases were observed.

[0044] To demonstrate the photoluminescence properties of NPN-0.01CT, excitation and emission spectra were tested. The test results are as follows: Figure 2 As shown. The excitation spectrum was obtained by NPN-0.01CT measurement at a wavelength of 611 nm. Using the optimal excitation wavelength of 290 nm, the emission wavelength spectrum of 580–650 nm was obtained. (The last part, "Pr," appears to be a separate, unrelated statement and is left as is.) 3+ of 1 D2→ 3 H4 transition is achieved, emitting an orange-red light.

[0045] The photoluminescence properties of NPN-0.01CT are as follows: Figure 3 As shown, under 290nm light excitation, orange-red emission centered at 611nm was observed, emitting orange-red light.

[0046] To demonstrate the stress-luminescence properties of the stress-luminescent material, its tribo-stress luminescence performance was tested under conditions of 15N frictional force and ultraviolet lamp radiation (365nm, 5min). Figure 4 These are the results of friction stress testing.

[0047] Example 2

[0048] 1) Add Na2CO3 and Pr6O 11 Using CaCO3, TiO2, and Nb2O5 as raw materials, according to the chemical formula Na 0.955 Ca 0.03 Pr 0.005 Nb 0.97 Ti 0.03 O3 is used as an ingredient, namely: 5.0610g Na2CO3, 0.0851g Pr6O 11 0.3002g CaCO3, 0.2396g TiO2, and 12.8918g Nb2O5 were placed in an agate ball mill jar, and 80ml of anhydrous ethanol was added. The mixture was ball-milled at 300r / min for 12h. After removal, it was dried at 80℃. It was then sintered in an oven, heated to 900℃ at a rate of 10℃ / min and held for 9h. After cooling to room temperature, it was ground for 60min. It was then placed in the oven again, held at 1200℃ for 6h, and ground for 60min to obtain the phosphor (abbreviated as NPN-0.03CT).

[0049] 2) Mix epoxy resin and alicyclic amine at a weight ratio of 10:1 until no bubbles are generated to obtain a resin mixture. Prepare the phosphor and resin mixture by mixing them at a weight ratio of 1:5.

[0050] 3) Apply petroleum jelly to the inner surface of the polytetrafluoroethylene mold, pour the phosphor prepared in step 2) into the bottom of the mold and spread it evenly, then pour the resin mixture prepared in step 2) into the mold, let it stand in air for 5 minutes, then transfer it to an oven and dry it at 60°C for 4 hours. Take it out, demold it, and you will get the stress luminescent material.

[0051] To demonstrate the phase structure of NPN-0.03CT, XRD tests were performed, such as... Figure 1 The diffraction peaks are consistent with the standard peaks of sodium niobate, and the test results are consistent with those of Example 1.

[0052] The photoluminescence properties of NPN-0.03CT are as follows: Figure 5 As shown, under 290nm light excitation, orange-red emission centered at 611nm was observed. The emission position did not change significantly compared with Example 1, and orange-red light was emitted.

[0053] Figure 6 The results of the triboluminescence test of the stress-luminescent material are shown. The test conditions are the same as in Example 1, and the triboluminescence intensity is 421.77 au.

[0054] Example 3

[0055] 1) Add Na2CO3 and Pr6O 11 Using CaCO3, TiO2, and Nb2O5 as raw materials, according to the chemical formula Na 0.935 Ca 0.05 Pr 0.005 Nb 0.95 Ti 0.05 O3 is used as an ingredient, namely: 4.9550g Na2CO3, 0.0851g Pr6O 11 0.5004g CaCO3, 0.3994g TiO2, and 12.6260g Nb2O5 were placed in an agate ball mill jar, and 80ml of anhydrous ethanol was added. The mixture was treated at 200r / min for 6h, then dried at 80℃. The mixture was then placed in an oven for sintering, heated to 800℃ at a rate of 8℃ / min and held for 5h. After cooling to room temperature, the mixture was ground for 50min. The mixture was then placed in the oven again, held at 1100℃ for 4h, and ground for 45min to obtain the phosphor (abbreviated as NPN-0.05CT).

[0056] 2) Mix epoxy resin and alicyclic amine at a weight ratio of 6:1 until no bubbles are generated to obtain a resin mixture. Prepare the phosphor and resin mixture by mixing them at a weight ratio of 1:2.5.

[0057] 3) Apply petroleum jelly to the inner surface of the polytetrafluoroethylene mold, pour the phosphor prepared in step 2) into the bottom of the mold and spread it evenly, then pour the resin mixture prepared in step 2) into the mold, let it stand in air for 5 minutes, then transfer it to an oven and dry it at 60°C for 4 hours. Take it out, demold it, and you will get the stress luminescent material.

[0058] To demonstrate the phase structure of NPN-0.05CT, XRD tests were performed, such as... Figure 1 The diffraction peaks are consistent with the standard peaks of sodium niobate, and the test results are consistent with those of Example 1.

[0059] The photoluminescence properties of NPN-0.05CT are as follows: Figure 7 As shown, under 290nm light excitation, orange-red emission centered at 611nm was observed. The emission position did not change significantly compared with Example 1, and orange-red light was emitted.

[0060] Figure 8 The results of the triboluminescence test of the stress-luminescent material are shown. The test conditions are the same as in Example 1, and the triboluminescence intensity is 411.81 au.

[0061] Example 4

[0062] 1) Add Na2CO3 and Pr6O 11 Using CaCO3, TiO2, and Nb2O5 as raw materials, according to the chemical formula Na 0.915 Ca 0.07 Pr 0.005 Nb 0.93 Ti 0.07 O3 is used as an ingredient, namely: 4.8490g Na2CO3, 0.0851g Pr6O 11 0.7006g CaCO3, 0.5592g TiO2, and 12.3602g Nb2O5 were placed in an agate ball mill jar, and 80ml of anhydrous ethanol was added. The mixture was ball-milled at 100r / min for 12h. After removal, it was dried at 80℃. It was then sintered in an oven, heated to 900℃ at a rate of 3℃ / min and held for 3h. After cooling to room temperature, it was ground for 60min. It was then placed in the oven again, held at 1050℃ for 6h, and ground for 30min to obtain the phosphor (abbreviated as NPN-0.07CT).

[0063] 2) Mix epoxy resin and alicyclic amine at a weight ratio of 10:1 until no bubbles are generated to obtain a resin mixture. Prepare the phosphor and resin mixture by mixing them at a weight ratio of 1:1.

[0064] 3) Apply petroleum jelly to the inner surface of the polytetrafluoroethylene mold, pour the phosphor prepared in step 2) into the bottom of the mold and spread it evenly, then pour the resin mixture prepared in step 2) into the mold, let it stand in air for 5 minutes, then transfer it to an oven and dry it at 60°C for 4 hours. Take it out, demold it, and you will get the stress luminescent material.

[0065] To demonstrate the phase structure of NPN-0.07CT, XRD tests were performed, such as... Figure 1 The diffraction peaks are consistent with the standard peaks of sodium niobate, and the test results are consistent with those of Example 1.

[0066] The photoluminescence properties of NPN-0.07CT are as follows: Figure 9 As shown, under 290nm light excitation, a strong red emission centered at 611nm was observed. The emission position did not change significantly compared with Example 1, and it emitted orange-red light.

[0067] Figure 10 The results are from the triboluminescence test of the stress-luminescent material, and the test conditions are the same as in Example 1.

[0068] Example 5

[0069] 1) Add Na2CO3 and Pr6O 11 Using CaCO3, TiO2, and Nb2O5 as raw materials, according to the chemical formula Na 0.895 Ca 0.09 Pr 0.005 Nb 0.91 Ti 0.09 O3 is used in the preparation, namely: 4.7430g Na2CO3, 0.0851g Pr6O 11 0.9008g CaCO3, 0.7189g TiO2, and 12.0943g Nb2O5 were placed in an agate ball mill jar, and 80ml of anhydrous ethanol was added. The mixture was treated at 300r / min for 2h, then dried at 80℃. The mixture was then placed in an oven for sintering, heated to 700℃ at a rate of 10℃ / min and held for 9h. After cooling to room temperature, the mixture was ground for 30min. The mixture was then placed in the oven again, held at 1200℃ for 2h, and ground for 60min to obtain the phosphor (abbreviated as NPN-0.07CT).

[0070] 2) Mix epoxy resin and alicyclic amine at a weight ratio of 3:1 until no bubbles are generated to obtain a resin mixture. Prepare the phosphor and resin mixture by mixing them at a weight ratio of 1:5.

[0071] 3) Apply petroleum jelly to the inner surface of the polytetrafluoroethylene mold, pour the phosphor prepared in step 2) into the bottom of the mold and spread it evenly, then pour the resin mixture prepared in step 2) into the mold, let it stand in air for 5 minutes, then transfer it to an oven and dry it at 60°C for 4 hours. Take it out, demold it, and you will get the stress luminescent material.

[0072] To demonstrate the phase structure of NPN-0.09CT, XRD tests were performed, such as... Figure 1 The diffraction peaks are consistent with the standard peaks of sodium niobate, and the test results are consistent with those of Example 1.

[0073] The photoluminescence properties of NPN-0.09CT are as follows: Figure 11 As shown, under 290nm light excitation, orange-red emission centered at 611nm was observed. The emission position did not change significantly compared with Example 1, and orange-red light was emitted.

[0074] Figure 12 The results are from the triboluminescence test of the stress-luminescent material, and the test conditions are the same as in Example 1.

[0075] Compare with Example 1

[0076] 1) Add Na2CO3 and Pr6O 11 Using Nb2O5 as raw material according to the chemical formula Na 0.985 Pr 0.005 The ingredients are NbO3, specifically: 5.2199g Na2CO3 and 0.0851g Pr6O3. 11 13.2905g of Nb2O5 was placed in an agate ball mill jar, and 80ml of anhydrous ethanol was added. The mixture was treated at 100r / min for 2h. After being removed and dried, it was placed in an oven for sintering. The temperature was increased to 700℃ at a rate of 3℃ / min and held for 3h. After cooling to room temperature, it was ground for 30min. The mixture was then placed in the oven again and held at 1050℃ for 2h. After grinding for 30min, the phosphor (NPN) was obtained.

[0077] 2) Mix epoxy resin and alicyclic amine at a weight ratio of 3:1 until no bubbles are generated to obtain a resin mixture. Prepare the phosphor and resin mixture by mixing them at a weight ratio of 1:1.

[0078] 3) Apply petroleum jelly to the inner surface of the polytetrafluoroethylene mold, pour the phosphor prepared in step 2) into the bottom of the mold and spread it evenly, then pour the resin mixture prepared in step 2) into the mold, let it stand in air for 5 minutes, then transfer it to an oven and dry it at 60°C for 4 hours. Take it out, demold it, and you will get the stress luminescent material.

[0079] To demonstrate the phase structure of NPN, XRD tests were performed, such as... Figure 1 The diffraction peaks are consistent with the standard peaks of sodium niobate, and the test results are consistent with those of Example 1.

[0080] The photoluminescence properties of NPN, such as Figure 13 As shown, under 290nm light excitation, orange-red emission centered at 611nm was observed. The emission position did not change significantly compared with Example 1, and orange-red light was emitted.

[0081] Figure 14 The results of the triboluminescence test of the stress-luminescent material are shown. The test conditions are the same as in Example 1. The luminescence intensity of this stress-luminescent material is poor.

Claims

1. A method for preparing an orange-red sodium niobate-calcium titanate stress luminescent material, characterized in that: Includes the following steps: 1) Add Na2CO3 and Pr6O 11 Using CaCO3, TiO2, and Nb2O5 as raw materials, according to the chemical formula Na 0.985-x Ca x Pr 0.005 Nb 1-x Ti x O3 is used as an ingredient, and the mixture is ball-milled using anhydrous ethanol as a solvent. After drying, it undergoes a first firing, a first grinding, a second firing, and a second grinding to obtain the phosphor. Here, x represents the mole fraction, and 0.03 ≤ x ≤ 0.

05. 2) Mix epoxy resin and alicyclic amine at a mass ratio of 3 to 10:1 to obtain a resin mixture; 3) Pour a mixture of phosphor and resin in a mass ratio of 1:1 to 5 into the mold, let it stand, dry it, and demold it to obtain the stress luminescent material.

2. The method for preparing the orange-red sodium niobate-calcium titanate stress luminescent material according to claim 1, characterized in that: x=0.03。 3. The method for preparing the orange-red sodium niobate-calcium titanate stress luminescent material according to claim 1, characterized in that: In step 1), the ball milling is carried out at a ball milling speed of 100-300 r / min for 2-12 hours.

4. The method for preparing the orange-red sodium niobate-calcium titanate stress luminescent material according to claim 1, characterized in that: In step 1), the first firing involves heating to 700-900°C at a rate of 3-10°C / min and holding at that temperature for 3-9 hours.

5. The method for preparing the orange-red sodium niobate-calcium titanate stress luminescent material according to claim 1, characterized in that: In step 1), the second firing is carried out at 1050-1200℃ for 2-6 hours.

6. The method for preparing the orange-red sodium niobate-calcium titanate stress luminescent material according to claim 1, characterized in that: In step 1), the first and second grinding times are both 30 to 60 minutes.

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