Multi-element rare earth doped vanadate-based luminescent material and preparation method thereof

Abstract

The invention discloses a multi-element rare earth doped vanadate-based luminescent material and a preparation method thereof, and belongs to the field of rare earth luminescent material preparation. A multi-element rare earth doped vanadate-based luminescent material comprises A, B and C, A, B and C are rare earth elements, A, B and C are different, the chemical formula of the luminescent material is (AxB1-x) 1-yVO4: Cy, x is more than or equal to 0.10 and less than or equal to 1.00, and y is more than or equal to 0.01 and less than or equal to 0.10; the invention can overcome the problems of general luminous intensity, poorer stability and shorter service life of the luminescent material.

Description

Technical Field

[0001] The present invention relates to the technical field of rare earth luminescent material preparation, and in particular to a multi-component rare earth doped vanadate-based luminescent material and a preparation method thereof. Background Art

[0002] Rare earth elements (RE) are a general term for 17 elements in the periodic table, from lanthanum (La), element 57, to lutetium (Lu), scandium (Sc) and yttrium (Y), element 71. Due to the unique 4f shell electronic structure and a large number of energy levels of rare earth elements, rare earth ions can form rare earth coordination compounds with coordination numbers ranging from 3 to 10. In addition, due to their strong spin-orbit coupling ability and large atomic magnetic moment, rare earth compounds can present a variety of crystal structures. Due to these characteristics, rare earth compounds can be used in high-tech industries such as automotive parts, aerospace technology, and precision strike weapons for military equipment, among which rare earth luminescent (fluorescent) materials are an important research and application direction.

[0003] Rare earth luminescent (fluorescent) materials are a general term for luminescent (fluorescent) materials that use 17 rare earth elements as matrices or activators, co-activators, dopants, and sensitizers. Although luminescence is a macroscopic phenomenon, it is inseparable from a series of microscopic properties inside the crystal. These microscopic properties are mainly energy transfer, carrier migration, crystal defects, and band structure. Usually, the luminescence process is that rare earth ions absorb energy, are in an excited state, transition from a low energy level to a high energy level, and then transition from a high energy level back to a low energy ground state through radiative relaxation, releasing energy in the form of radiated photons.

[0004] As the most traditional rare earth luminescent materials with relatively mature preparation technology and excellent luminescent performance, people have conducted relatively in-depth research on rare earth vanadium-doped luminescent materials. As early as 1964, foreign researchers invented the highly efficient red phosphor YVO using rare earth separation technology. 4 :Eu; The selection and design of the rare earth luminescent material matrix is ​​crucial to achieving excellent luminescent performance. According to the requirements of the required light color and luminescent characteristics, the existing rare earth luminescent materials have the advantages of excellent luminescent efficiency, non-toxicity, simple preparation, low cost, etc., but their luminescent intensity is general, the stability is poor, and the lifespan is short during use; on the basis of basic conditions, the composition and structure of the material are modified and designed, and then combined with different preparation processes, the ideal rare earth luminescent material can be obtained. Summary of the invention

[0005] The purpose of the present invention is to solve the problems of general luminous intensity, poor stability and short service life of luminescent materials in the prior art, and to propose a multi-rare earth doped vanadate-based luminescent material and a preparation method thereof.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A multi-element rare earth doped vanadate-based luminescent material, comprising A, B, and C, wherein A, B, and C are all rare earth elements and A, B, and C are different from each other. The chemical formula of the luminescent material is (A x B 1-x ) 1-y VO 4 :C y , where the values ​​of x and y are as follows: 0.10≤x≤1.00, 0.01≤y≤0.10.

[0008] Preferably, the rare earth elements include lanthanum, cerium, neodymium, dysprosium, ytterbium, lutetium, yttrium, gadolinium, erbium, europium, and samarium.

[0009] A method for preparing a multi-element rare earth doped vanadate-based luminescent material comprises the following steps:

[0010] Step 1: Water bath co-precipitation powder preparation: A(NO 3 ) 3 6H 2 O、B(NO 3 ) 3 6H 3 O、C(NO 3 ) 3 6H 2 O and NaVO 3 Add into water and stir to obtain a yellow mixed solution;

[0011] Step 2: Drop the yellow mixed solution into the organic acid solution in a water bath and stir continuously;

[0012] Step 3: After the yellow mixed solution is added dropwise, it is aged. After the upper layer of liquid is clarified, the precipitate obtained by the reaction is washed with water and alcohol in sequence until it is neutral and filtered to obtain a precursor wet powder;

[0013] Step 4: Dry the precursor wet powder in a blast drying oven to obtain a precursor dry powder, and grind it with a mortar;

[0014] Step 5: Reciprocating high-temperature calcination: Place the precursor dry powder in a muffle furnace and calcine to obtain a multi-component rare earth doped luminescent material.

[0015] Further, in step 1, the mixed nitrate solution A 3+ , B 3+ , C 3+ and VO 3- The concentration of NH in ammonia is 0.1-0.3 mol / L. 3 The mass fraction is 25-28wt.%.

[0016] Furthermore, in step 1 and step 2, the concentration of the organic acid in the organic acid solution is 0.2-0.4 mol / L, and the volume ratio of the mixed nitrate solution to the organic acid solution is 1:3-5.

[0017] Furthermore, the organic acid includes ammonium oxalate (NH 4 ) 2 C 2 O 4 , oxalic acid H 2 C 2 O 4 , Citric acid C 6 H 8 O 7 , C 4 H 6 O 6 .

[0018] Furthermore, in step 2, the water bath temperature of the organic acid solution is 40-60° C., and the dropping speed of the yellow mixed solution is 3-5 / 2s.

[0019] Furthermore, in step three, the aging time after the yellow mixed solution is added dropwise is 3-6 hours.

[0020] Furthermore, in step 4, the drying temperature of the precursor wet powder in the blower drying oven is 80-100° C., and the drying time is 1-3 hours.

[0021] Furthermore, in step five, the precursor dry powder is initially heated to a temperature of 600-800°C in a muffle furnace at a heating efficiency of 5-8°C / min, and is kept warm for 1-3 hours. The precursor dry powder is then naturally cooled to a temperature of 200-400°C, and then heated to a temperature of 800-1100°C at a heating efficiency of 1-3°C / min, and is kept warm for 1-3 hours.

[0022] Compared with the prior art, the present invention provides a multi-element rare earth doped vanadate-based luminescent material and a preparation method thereof, which has the following beneficial effects:

[0023] 1. The preparation method of the multi-element rare earth doped vanadate-based luminescent material is prepared by using a water bath co-precipitation method and a reciprocating high-temperature roasting process (A x B 1-x ) 1-y VO 4 :C y Multi-component rare earth doped luminescent material, and the prepared multi-component rare earth doped luminescent material has good crystallization condition and excellent luminescent performance, (A x B 1-x ) 1-yVO 4 :C y Luminescent material ratio A 1-y VO 4 :C y The luminous intensity of the luminescent material is increased by more than 190%, and the luminous intensity is also significantly improved compared with the same material system prepared by other methods.

[0024] 2. The preparation method of the multi-rare earth doped vanadate-based luminescent material, by adjusting the co-precipitation solution concentration, water bath temperature, pH and reciprocating high-temperature roasting temperature and time, prepares a multi-rare earth doped luminescent material with good crystallization condition and excellent luminescent performance, wherein the median particle size of the powder particles is below 1.2μm, and the particles with a particle size less than 2.5μm account for 84%, making the luminescent performance of the luminescent material better and more stable.

[0025] 3. The method for preparing the multi-element rare earth doped vanadate-based luminescent material can ensure that the reaction substances react completely and that the precipitation is evenly generated without agglomeration during the titration process by controlling the volume ratio of the mixed nitrate solution and the organic acid solution within the range of 1:3-5 and the pH of the reaction system within the range of 9-12.

[0026] The parts not involved in the device are the same as the prior art or can be implemented by using the prior art. The present invention can overcome the problems of general luminous intensity, poor stability and short service life of the luminescent material. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Y 0.5 G 0.5 ) 0.9 VO 4 :Er 0.1 Particle size distribution curve of powder;

[0028] Figure 2 This is the XRD pattern of multi-rare earth doped vanadate-based luminescent material;

[0029] Figure 3 It is the excitation spectrum and emission spectrum of multi-rare earth doped vanadate-based luminescent material;

[0030] Figure 4 Y 0.9 VO 4 :Sm 0.1 Excitation spectrum and emission spectrum of

[0031] Figure 5 Y 0.5 G 0.5 ) 0.9 VO 4 :Sm0.1 Excitation spectrum and emission spectrum of

[0032] Figure 6 for (La 0.75 Ce 0.25 ) 0.9 VO 4 :Sm 0.1 Excitation spectrum and emission spectrum of

[0033] Figure 7 for (La 0.75 Ce 0.25 ) 0.96 VO 4 :Sm 0.04 Excitation and emission spectra. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0035] Embodiment 1:

[0036] A multi-element rare earth doped vanadate-based luminescent material, comprising A, B, and C, wherein A, B, and C are all rare earth elements, and the rare earth elements include lanthanum, cerium, neodymium, dysprosium, ytterbium, lutetium, yttrium, gadolinium, erbium, europium, and samarium, and A, B, and C are different from each other. The chemical formula of the luminescent material is (A x B 1-x ) 1- y VO 4 :C y , where the values ​​of x and y are as follows: 0.10≤x≤1.00, 0.01≤y≤0.10.

[0037] A method for preparing a multi-element rare earth doped vanadate-based luminescent material comprises the following steps:

[0038] Step 1: Water bath co-precipitation powder preparation: A(NO 3 ) 3 6H 2 O、B(NO 3 ) 3 6H 3 O、C(NO 3 ) 3 6H 2 O and NaVO 3 Add into water and stir to obtain a yellow mixed solution;

[0039] In step 1, a nitrate solution is mixed with 3+ , B3+ , C 3+ and VO 3- The concentration of NH in ammonia is 0.1-0.3 mol / L. 3 The mass fraction is 25-28wt.%, and the amount of ammonia water added is determined according to the pH value in the reaction system being controlled within the range of 9-12.

[0040] Step 2: Drop the yellow mixed solution into the organic acid solution in a water bath and stir continuously;

[0041] In step one and step two, the concentration of the organic acid in the organic acid solution is 0.2-0.4 mol / L, and the volume ratio of the mixed nitrate solution to the organic acid solution is 1:3-5. The present application controls the concentration of the organic acid in the organic acid solution within the range of 0.2-0.4 mol / L, thereby ensuring that the particle size of the powder slurry obtained after washing the generated precipitate is less than 3 μm, and the particle size of the powder slurry is relatively uniform. When the volume ratio of the mixed nitrate solution to the organic acid solution is 1:3-5, and the pH value in the reaction system is controlled within the range of 9-12, not only can the substance reaction be ensured to be complete, but also the precipitate can be uniformly produced during the titration process without agglomeration.

[0042] In step 2, the water bath temperature of the organic acid solution is 40-60°C, the dropping speed of the yellow mixed solution is 3-5 / 2s, and during titration, the pH value of the reaction system is maintained in the range of 9-12. The water bath temperature is controlled at 40-60° to make the material heated more evenly and improve the reaction efficiency of the material;

[0043] Organic acids include ammonium oxalate (NH 4 ) 2 C 2 O 4 , oxalic acid H 2 C 2 O 4 , Citric acid C 6 H 8 O 7 , C 4 H 6 O 6 In the preparation of rare earth luminescent materials, the organic acid can be ammonium oxalate, oxalic acid, citric acid or tartaric acid, and these organic acids can be used to synthesize rare earth luminescent materials in terms of chemical properties.

[0044] Step 3: After the yellow mixed solution is added dropwise, it is aged. After the upper layer of liquid is clarified, the precipitate obtained by the reaction is washed with water and alcohol in sequence until it is neutral and filtered to obtain a precursor wet powder;

[0045] In step three, the aging time after the yellow mixed solution is added is 3-6 hours. This is to allow the components in the mixed solution to react fully, which is conducive to the complete precipitation of the precipitate, so as to better separate the impurities in the precipitate, improve the purity, and make the particle size distribution more uniform.

[0046] Step 4: Dry the precursor wet powder in a blast drying oven to obtain a precursor dry powder, and grind it with a mortar;

[0047] In step 4, the precursor wet powder is dried in a blower drying oven at a temperature of 80-100°C for 1-3 hours. In this process, water and alcohol in the wet powder can be removed. Grinding can also disperse the agglomerated powder and make the mixed powder more evenly mixed.

[0048] Step 5: Reciprocating high-temperature calcination: Place the precursor dry powder in a muffle furnace and calcine to obtain a multi-element rare earth doped luminescent material;

[0049] In step five, the precursor dry powder is initially heated to a temperature of 600-800°C in a muffle furnace with a heating efficiency of 5-8°C / min, and is kept warm for 1-3 hours. The precursor dry powder is then naturally cooled to a temperature of 200-400°C, and then heated to a temperature of 800-1100°C with a heating efficiency of 1-3°C / min, and is kept warm for 1-3 hours. Reciprocating high-temperature calcination can remove impurities in the precursor dry powder, promote chemical reactions, change the material and chemical properties of the precursor dry powder, and thus improve the stability of the luminescent material.

[0050] Embodiment 2:

[0051] This embodiment is a multi-element rare earth doped vanadate-based luminescent material and a preparation method thereof. The chemical formula of the luminescent material is (Y 0.5 G 0.5 ) 0.9 VO 4 :Er 0.1 (ie: A is Y, B is Gd, C is Er, x=0.5, y=0.1), and the preparation method thereof comprises the following steps:

[0052] Step 1: According to the molar ratio of V, Y and Sm of 1.00:0.90:0.10, NaVO 3 Powder, Y(NO 3 ) 3 6H 2 O powder and Sm(NO 3 ) 3 6H 2 Add O powder into water and stir to obtain a yellow mixed solution. 3+ 、Sm 3+and VO 3- The concentration of is 0.25mol / L;

[0053] Step 2: Mix the nitrate solution and ammonia water (NH 3 The mass fraction was 27 wt.%) and an organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) solution, the dripping speed is 4 drops / 2s, and the organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) solution of organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) concentration is 0.30 mol / L; during titration, the pH of the reaction system is maintained at 10. In this embodiment, a nitrate solution, an organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) solution and ammonia water in a volume ratio of 1:5:0.15;

[0054] Step 3: After the titration reaction is completed and the upper liquid is clarified after aging for 5 hours, the precipitate obtained by the reaction is washed with water (using deionized water) and alcohol (using anhydrous ethanol) in sequence until it is neutral (pH = 7) and filtered to obtain a precursor wet powder;

[0055] Step 4: The precursor wet powder is dried in a 100°C forced air drying oven for 2 hours and ground with a mortar to remove water and alcohol from the wet powder. Grinding can also disperse the agglomerated powder and make the mixed powder more uniform.

[0056] Step 5: The precursor dry powder is heated to 700°C at 5°C / min in a muffle furnace, kept at this temperature for 1 hour, cooled naturally to 200°C, and then heated to 800°C, 900°C and 1000°C at 3°C / min, kept at this temperature for 3 hours, to obtain a multi-element rare earth doped vanadate-based luminescent material;

[0057] Figure 1 Y 0.5 G 0.5 ) 0.9 VO 4 :Er 0.1The particle size distribution curve of the powder (calcined at 900℃ for 3h) shows that the median particle size of the slurry powder particles is below 1.2μm, and the slurry powder particles with a particle size less than 2.5μm account for 84%, which helps to obtain luminescent materials with better and more stable luminescent properties, thereby extending the service life of the luminescent materials; Figure 2 The XRD diagram of the multi-rare earth doped vanadate-based luminescent material (calcined at 800℃, 900℃ and 1000℃ for 3h) is shown in Figure 2. The multi-rare earth doped vanadate-based luminescent material consists of the main phase Y 0.5 G 0.5 VO 4 With doped phase ErVO 4 composition, among which the peak intensity of the main peak at 900℃ is the highest, and the crystallinity of the material is the best; Figure 3 These are the excitation and emission spectra of a multi-rare earth doped vanadate-based luminescent material (calcined at 900°C for 3h). The excitation and emission spectra intensities of the material are 609517 a.u. and 570425 a.u., respectively.

[0058] Embodiment three:

[0059] This embodiment is a multi-element rare earth doped vanadate-based luminescent material and a preparation method thereof. The chemical formula of the luminescent material is Y 0.9 VO 4 :Sm 0.1 (ie: A is Y, C is Sm, x=1.0, y=0.1), and the preparation method thereof comprises the following steps:

[0060] Step 1: According to the molar ratio of V, Y, Gd and Sm of 1.00:0.45:0.45:0.10, NaVO 3 Powder, Y(NO 3 ) 3 6H 2 O powder, Gd(NO 3 ) 3 6H 2 O powder and Sm(NO 3 ) 3 6H 2 Add O powder into water and stir to obtain a yellow mixed solution. 3+ , Gd 3+ 、Sm 3+ and VO 3- The concentration of is 0.25mol / L;

[0061] Step 2: Mix the nitrate solution and ammonia water (NH 3 The mass fraction was 27 wt.%) and an organic acid (ammonium oxalate (NH 4 ) 2 C2 O 4 ) solution, the dripping speed is 4 drops / 2s, and the organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) solution of organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) concentration is 0.30 mol / L. During titration, the pH of the reaction system is maintained at 10. In this embodiment, a nitrate solution and an organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) solution and ammonia water in a volume ratio of 1:5:0.15;

[0062] Step 3: After the titration reaction is completed and the upper liquid is clarified after aging for 5 hours, the precipitate obtained by the reaction is washed with water (using deionized water) and alcohol (using anhydrous ethanol) in sequence until it is neutral (pH = 7) and filtered to obtain a precursor wet powder;

[0063] Step 4: The precursor wet powder is dried in a 90°C forced air drying oven for 3 hours and ground with a mortar to remove water and alcohol from the wet powder. Grinding can also disperse the agglomerated powder and make the mixed powder more uniform;

[0064] Step 5: The precursor dry powder is heated to 600°C at 6°C / min in a muffle furnace, kept at this temperature for 2 hours, cooled naturally to 300°C, and then heated to 900°C at 2°C / min, kept at this temperature for 3 hours, to obtain a multi-element rare earth doped vanadate-based luminescent material;

[0065] Figure 4 Y 0.9 VO 4 :Sm 0.1 Excitation and emission spectra of powder.

[0066] Embodiment 4:

[0067] This embodiment is a multi-element rare earth doped vanadate-based luminescent material and a preparation method thereof. The chemical formula of the luminescent material is (Y 0.5 G 0.5 ) 0.9 VO 4 :Sm 0.1 (ie: A is Y, B is Gd, C is Sm, x=0.5, y=0.1), and the preparation method thereof comprises the following steps:

[0068] Step 1: According to the molar ratio of V, Y, Gd and Sm of 1.00:0.45:0.45:0.10, NaVO 3 Powder, Y(NO 3 ) 3 6H 2 O powder, Gd(NO 3 ) 3 6H 2 O powder and Sm(NO 3 ) 3 6H 2 Add O powder into water and stir to obtain a yellow mixed solution. 3+ , Gd 3+ 、Sm 3+ and VO 3- The concentration of is 0.25mol / L;

[0069] Step 2: Mix the nitrate solution and ammonia water (NH 3 The mass fraction was 27 wt.%) and an organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) solution, the dripping speed is 4 drops / 2s, and the organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) solution of organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) concentration is 0.30 mol / L; during titration, the pH of the reaction system is maintained at 10. In this embodiment, a nitrate solution, an organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) solution and ammonia water in a volume ratio of 1:5:0.15;

[0070] Step 3: After the titration reaction is completed and the upper liquid is clarified after aging for 5 hours, the precipitate obtained by the reaction is washed with water (using deionized water) and alcohol (using anhydrous ethanol) in sequence until it is neutral (pH = 7) and filtered to obtain a precursor wet powder;

[0071] Step 4: The precursor wet powder is dried in a 90°C forced air drying oven for 3 hours and ground with a mortar to remove water and alcohol from the wet powder. Grinding can also disperse the agglomerated powder and make the mixed powder more uniform;

[0072] Step 5: The precursor dry powder is heated to 600°C at 6°C / min in a muffle furnace, kept at this temperature for 2 hours, cooled naturally to 300°C, and then heated to 900°C at 2°C / min, kept at this temperature for 3 hours, to obtain a multi-element rare earth doped vanadate-based luminescent material;

[0073] Figure 5 Y 0.5 G 0.5 ) 0.9 VO 4 :Sm 0.1 The excitation spectrum and emission spectrum of the powder. The excitation spectrum intensity and emission spectrum intensity of the material are 1215114.63au and 1216100.63au respectively. Figure 4 and Figure 5 In comparison, under the same preparation conditions, the luminescence intensity of the ternary emission is more than 190% higher than that of the binary emission.

[0074] Embodiment five:

[0075] This embodiment is a multi-element rare earth doped vanadate-based luminescent material and a preparation method thereof. The chemical formula of the luminescent material is (La 0.75 Ce 0.25 ) 0.9 VO 4 :Sm 0.1 (ie: A is La, B is Ce, C is Sm, x=0.75, y=0.10), and the preparation method thereof comprises the following steps:

[0076] Step 1: According to the molar ratio of V, La, Ce and Sm of 1.00:0.675:0.225:0.10, NaVO 3 Powder, La(NO 3 ) 3 6H 2 O powder, Ce(NO 3 ) 3 6H 2 O powder and Sm(NO 3 ) 3 6H 2 O powder was added into water and stirred to obtain a yellow mixed solution. 3+ 、Ce 3+ 、Sm 3+ and VO 3- The concentration of is 0.28mol / L;

[0077] Step 2: Mix the nitrate solution and ammonia water (NH 3 The mass fraction was 27 wt.%) and an organic acid (ammonium oxalate (NH 4 ) 2C 2 O 4 ) solution, the dripping speed is 4 drops / 2s, and the organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) solution of organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) concentration is 0.33 mol / L; during titration, the pH of the reaction system is maintained at 11. In this embodiment, a nitrate solution, an organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) solution and ammonia water in a volume ratio of 1:5:0.15;

[0078] Step 3: After the titration reaction is completed and the upper liquid is clarified after aging for 4 hours, the precipitate obtained by the reaction is washed with water (using deionized water) and alcohol (using anhydrous ethanol) in sequence until it is neutral (pH = 7) and filtered to obtain a precursor wet powder;

[0079] Step 4: The precursor wet powder is dried in a 100°C forced air drying oven for 3 hours and ground with a mortar to remove water and alcohol from the wet powder. Grinding can also disperse the agglomerated powder and make the mixed powder more uniform.

[0080] Step 5: The precursor dry powder is heated to 700°C at 7°C / min in a muffle furnace, kept warm for 1 hour, cooled naturally to 200°C, and then heated to 1000°C at 3°C / min, kept warm for 2 hours, to obtain a multi-element rare earth doped vanadate-based luminescent material;

[0081] Figure 6 for (La 0.75 Ce 0.25 ) 0.9 VO 4 :Sm 0.1 From the excitation spectrum and emission spectrum of the powder, it can be seen that the luminescence intensity of the obtained material is also relatively excellent.

[0082] Embodiment six:

[0083] This embodiment is a multi-element rare earth doped vanadate-based luminescent material and a preparation method thereof. The chemical formula of the luminescent material is (La 0.75 Ce 0.25 ) 0.96 VO 4 :Sm 0.04(ie: A is La, B is Ce, C is Sm, x=0.75, y=0.04), and the preparation method thereof comprises the following steps:

[0084] Step 1: According to the molar ratio of V, La, Ce and Sm of 1.00:0.72:0.24:0.04, NaVO 3 Powder, La(NO 3 ) 3 6H 2 O powder, Ce(NO 3 ) 3 6H 2 O powder and Sm(NO 3 ) 3 6H 2 O powder was added into water and stirred to obtain a yellow mixed solution. 3+ 、Ce 3+ 、Sm 3+ and VO 3- The concentration of is 0.28mol / L;

[0085] Step 2: Mix the nitrate solution and ammonia water (NH 3 The mass fraction was 27 wt.%) and an organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) solution, the dripping speed is 4 drops / 2s, and the organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) solution of organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) concentration is 0.33 mol / L; during titration, the pH of the reaction system is maintained at 11. In this embodiment, a nitrate solution, an organic acid (ammonium oxalate (NH 4 ) 2 C 2 O 4 ) solution and ammonia water in a volume ratio of 1:5:0.15;

[0086] Step 3: After the titration reaction is completed and the upper liquid is clarified after aging for 4 hours, the precipitate obtained by the reaction is washed with water (using deionized water) and alcohol (using anhydrous ethanol) in sequence until it is neutral (pH = 7) and filtered to obtain a precursor wet powder;

[0087] Step 4: The precursor wet powder is dried in a 100°C forced air drying oven for 3 hours and ground with a mortar to remove water and alcohol from the wet powder. Grinding can also disperse the agglomerated powder and make the mixed powder more uniform.

[0088] Step 5: The precursor dry powder is heated to 700°C at 7°C / min in a muffle furnace, kept warm for 1 hour, cooled naturally to 200°C, and then heated to 1000°C at 3°C / min, kept warm for 2 hours, to obtain a multi-element rare earth doped vanadate-based luminescent material;

[0089] Figure 7 for (La 0.75 Ce 0.25 ) 0.96 VO 4 :Sm 0.04 From the excitation spectrum and emission spectrum of the powder, it can be seen that the luminescence intensity of the obtained material is also relatively excellent. Compared with Example 4, the luminescence intensity is improved significantly by increasing the La and Ce contents.

[0090] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A multi-element rare earth doped vanadate-based luminescent material, characterized in that: A, B, and C are included, wherein A, B, and C are all rare earth elements, and A, B, and C are different from each other. The chemical formula of the luminescent material is (A x B 1-x ) 1-y VO4:C y , Among them, the values ​​of x and y are as follows: 0.10≤x≤1.00, 0.01≤y≤0.

10.

2. The multi-element rare earth doped vanadate-based luminescent material according to claim 1, characterized in that: The rare earth elements include lanthanum, cerium, neodymium, dysprosium, ytterbium, lutetium, yttrium, gadolinium, erbium, europium, and samarium.

3. A method for preparing the multinary rare earth doped vanadate-based luminescent material according to any one of claims 1 to 2, characterized in that: The steps include: Step 1: Powder preparation by water bath co-precipitation method: A(NO3)3·6H2O, B(NO3)3·6H3O, C(NO3)3·6H2O and NaVO3 are added into water and stirred to obtain a yellow mixed solution; Step 2: Drop the yellow mixed solution into the organic acid solution in a water bath and stir continuously; Step 3: After the yellow mixed solution is added dropwise, it is aged. After the upper layer of liquid is clarified, the precipitate obtained by the reaction is washed with water and alcohol in sequence until it is neutral and filtered to obtain a precursor wet powder; Step 4: Dry the precursor wet powder in a blast drying oven to obtain a precursor dry powder, and grind it with a mortar; Step 5: Reciprocating high-temperature calcination: Place the precursor dry powder in a muffle furnace and calcine to obtain a multi-element rare earth doped luminescent material.

4. The method for preparing a multi-component rare earth doped vanadate-based luminescent material according to claim 3, characterized in that: In step 1, a nitrate solution is mixed with 3+ , B 3+ , C 3+ and VO 3- The concentration of NH3 is 0.1-0.3 mol / L, and the mass fraction of NH3 in ammonia water is 25-28 wt.%.

5. The method for preparing a multi-component rare earth doped vanadate-based luminescent material according to claim 4, characterized in that: In step 1 and step 2, the concentration of the organic acid in the organic acid solution is 0.2-0.4 mol / L, and the volume ratio of the mixed nitrate solution to the organic acid solution is 1:3-5.

6. The method for preparing a multi-component rare earth doped vanadate-based luminescent material according to claim 3, characterized in that: The organic acid includes ammonium oxalate (NH4)2C2O4, oxalic acid H2C2O4, citric acid C6H8O7, and C4H6O6.

7. The method for preparing a multi-component rare earth doped vanadate-based luminescent material according to claim 3, characterized in that: In step 2, the water bath temperature of the organic acid solution is 40-60° C., and the dropping speed of the yellow mixed solution is 3-5 drops / 2s.

8. The method for preparing a multi-element rare earth doped vanadate-based luminescent material according to claim 3, characterized in that: In step 3, the aging time after the yellow mixed solution is added dropwise is 3-6 hours.

9. The method for preparing a multi-component rare earth doped vanadate-based luminescent material according to claim 3, characterized in that: In step 4, the precursor wet powder is dried in a blower drying oven at a temperature of 80-100° C. for a drying time of 1-3 hours.

10. The method for preparing a multi-component rare earth doped vanadate-based luminescent material according to claim 3, characterized in that: In step 5, the precursor dry powder is first heated to 600-800°C in the muffle furnace at a heating rate of 5-8°C / min and kept warm for 1-3h. The precursor dry powder is then cooled naturally at a temperature of 200-400°C. The dry powder is heated to 800-1100℃ and the heating efficiency is 1-3℃ / min. And keep warm for 1-3h.

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