A rare earth co-doped complex material, a preparation method and application thereof

Abstract

The application belongs to the field of metal complex material preparation, and discloses a rare earth co-doped complex material, a preparation method and application thereof. The rare earth co-doped complex prepared by the application is stacked by basic structural units, and the basic structural unit is a four-nuclear rare earth co-doped complex, and the chemical molecular formula is [Ln2(BTDB)3(DMA)2(phen)] n , wherein Ln is a trivalent rare earth ion, Ln=Tb 3+ , Eu 3+ , and there are 183 Tb 3+ and 17 Eu 3+ in every 200 rare earth ions, BTDB is N,N-di(4-carboxyl)phenyl-3,5-bistrifluoromethyl aniline. The novel rare earth co-doped complex has double-rare earth center fluorescence emission characteristics under single excitation, and can be used for manufacturing Tb 3+ , Eu 3+ doped yellow emission fluorescent material of a non-dazzling white light emitting diode, and can adjust warm white light. The preparation method has simple process, low cost and high yield, and can be widely applied to anti-fake luminescent paper and / or optical devices.

Description

Technical Field

[0001] This invention belongs to the field of metal complex material preparation, specifically relating to a rare earth co-doped complex material, its preparation method, and its application. Background Technology

[0002] The energy efficiency of white light-emitting diodes (LEDs), as an important lighting source, has always been a focus of attention, and their luminous efficiency is constantly improving. Currently used white LEDs have extremely high brightness due to their very small luminous area, but the glare they produce causes discomfort and harms visual health. Based on colorimetry and the principle of light emission, two or more wavelengths of light can be combined to obtain white light emission. Many examples reported so far rely on multi-component combinations, with emitted colors covering the entire visible light range. White light sources produced by combining the three main RGB chromophores often suffer from complications, including colorimetric variations, phase separation, and complex packaging processes. They also have complex control circuits, unstable color temperature due to varying light decay, and high costs.

[0003] Over the past few decades, luminescent rare-earth ions have seen widespread applications due to their excellent luminescence properties and diverse emission characteristics. Luminescent rare-earth materials have been widely used in displays, anti-counterfeiting applications, biosensors, fiber optic amplifiers, lasers, optical temperature measurement, and lighting. However, traditional fluorescent lamps and incandescent light sources suffer from low luminous efficiency, lack of energy conservation and environmental friendliness, and short lifespan. Therefore, there is a strong need to develop efficient and stable white light emitting materials for displays and solid-state lighting. Furthermore, LED devices made with this novel warm white phosphor exhibit excellent warm white light quality even at high temperatures, which is essential for their practical applications. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a rare earth co-doped complex material, its preparation method, and its application. Specifically, the following technical solution is adopted: According to a first aspect of the present invention, a rare earth co-doped complex material is provided, the chemical formula of which is: [Ln2(BTDB)3(DMA)2(phen)] n Wherein, Ln is a trivalent rare earth ion, Ln = Tb 3+ Eu 3+ There are 183 Tb ions out of every 200 rare earth ions. 3+ and 17 Eu 3+ BTDB is N,N-bis(4-carboxy)phenyl-3,5-bis(trifluoromethylaniline). N,N-bis(4-carboxy)phenyl-3,5-bis(trifluoromethylaniline) was chosen as the ligand because this ligand molecule does not have oscillating groups, resulting in higher energy transfer efficiency.

[0005] The rare earth co-doped complex material is formed by the sequential stacking of basic structural units through van der Waals interactions. The basic structural unit is a tetranuclear rare earth complex, which is a neutral structural unit constructed by four crystallographically independent Ln, seven BTDB ligands, two 1,10-phenanthroline, and two DMA molecules. Among the seven BTDB ligands, there are 28 fully coordinated oxygens. Ln adopts octagonal and nintagonal coordination modes. The BTDB ligands adopt both bridging and chelating coordination modes with Ln. The N in the auxiliary ligand phenanthroline is chelated with Ln, and the O in the DMA is bridged with Ln. The bond lengths of Tb-O and Eu-O are between 2.282(4) and 2.802(5) Å, and the bond lengths of Tb-N and Eu-N are between 2.599(6) and 2.631(6) Å.

[0006] The rare earth co-doped complex material obtained by this invention crystallizes in the triclinic crystal system with space group [missing information]. P- 1. Unit cell parameters: a = 9.4234(2) ~ 9.4236(2) Å, b = 16.6721(4)~16.7480(4) Å, c = 27.7905(7) ~ 27.7954(7) Å, α =101.544(2) ~ 101.857(2)°, β = 94.166(2) ~94.257(2)°, γ = 93.113(2) ~93.531(2)°, V =4252.91(15)~ 4271.12(18) Å 3 , Z =2.

[0007] According to a second aspect of the present invention, a method for preparing the above-mentioned rare earth co-doped complex material is also provided, comprising the following steps: (a) Dissolve a soluble terbium salt and a soluble europium salt in a first solvent, mix well, and obtain a mixed solution A; the first solvent is an organic solvent; (b) N,N-bis(4-carboxy)phenyl-3,5-bistrifluoromethylaniline was added to the second solvent and mixed well to obtain mixed solution B; the second solvent was an organic solvent; (c) Add the obtained mixed solution B to mixed solution A to obtain mixed solution C; (d) Add 1,10-o-phenanthroline to the third solvent and mix well to obtain a mixed solution D; the third solvent is an organic solvent; (e) Add the obtained mixed solution D to mixed solution C to obtain mixed solution E; (f) Add the obtained mixed solution E to the fourth solvent and mix well to obtain mixed solution F; the fourth solvent is water or an organic solvent; (g) The obtained mixed solution F is reacted at 70 ℃-90 ℃ to obtain rare earth co-doped complex material.

[0008] The preparation method employed in this invention is simple, low-cost, and has a high yield, making it suitable for industrial production. Furthermore, the choice of the main ligand can be modified, allowing the use of commercially available or newly synthesized ligands, such as 5-fluorobenzoic acid. The blue dye triphenylamine used to modulate white light can also be changed; any material that emits blue light under ultraviolet light can be used to modulate the white light of the rare-earth co-doped complex. Compared to traditional fluorescent lamps and incandescent light sources, white light-emitting diodes (W-LEDs) generated by rare-earth ion doping of phosphors offer numerous advantages, including higher luminous efficiency, energy saving, environmental friendliness, long lifespan, and excellent reliability.

[0009] Preferably, the soluble terbium salt is any one of terbium nitrate, terbium chloride, terbium acetate, terbium sulfonate, terbium oxalate, and terbium trifluoromethanesulfonate. The soluble europium salt is any one of europium nitrate, europium chloride, europium acetate, europium sulfonate, europium oxalate, and europium trifluoromethanesulfonate. In steps (a), (b), (d), and (f), the organic solvent is at least one of dimethylacetamide, N,N-dimethylformamide, methanol, acetone, tetrahydrofuran, ethanol, acetonitrile, dichloromethane, and trichloromethane.

[0010] Preferably, the molar ratio of N,N-bis(4-carboxy)phenyl-3,5-bis(trifluoromethylaniline), soluble terbium salt, and soluble europium salt is 21:15:1. When the raw materials are added in the specified proportions, the resulting crystals are orange-yellow. Fluorescence spectroscopy tests on the obtained crystals show that the fluorescence intensities at the highest characteristic emission peaks of the bimetallic ions at 544 nm and 614 nm are closest, with an intensity difference of no more than 10%. According to the principle of three primary colors, the product obtained in this proportion is suitable as the optimal choice for white light powder adjustment.

[0011] Preferably, in step (g), the reaction time is 2-6 days. When the reaction time is less than 2 days, almost no bulk crystals suitable for X-ray single-crystal diffraction testing are generated in the flask, and even fine crystals are not generated, making it difficult to determine the material composition. When the reaction time exceeds 6 days, polycrystalline materials will continue to form on the surface of the already generated crystals. Polycrystalline materials are not suitable for X-ray single-crystal diffraction testing, making it impossible to obtain the accurate structural composition of the polycrystalline materials and increasing the presence of uncertain components. Therefore, a reaction time of 2-6 days is selected.

[0012] According to a third aspect of the present invention, the application of rare earth co-doped complex materials prepared by the above method in anti-counterfeiting luminescent paper and / or optical devices is also provided.

[0013] The rare-earth co-doped complexes prepared by this invention exhibit dual emission characteristics under single excitation, and can be used to manufacture Tb in glare-free white light-emitting diodes. 3+ Eu 3+ This rare-earth co-doped complex, doped with a yellow phosphor, exhibits a large Stokes shift, effectively converting violet excitation light into yellow emission. Mixing it with different proportions of triphenylamine allows for chromaticity tuning from orange-yellow to white light, including the tuning of an ideal warm white light. Its CIE coordinates are (0.3312, 0.3557) and (0.3137, 0.3305). Compared to previous methods of tuning white light using red, green, and blue primary colors, this tuning method not only reduces the difficulty of white light tuning but also largely solves the problem of color temperature instability caused by different light decay in tri-color combinations. The triphenylamine used is inexpensive, possesses a strong conjugated system, and high thermal stability, with a melting point of 125 ℃-127 ℃ and a flash point of 157.3 °C. The phosphor exhibits excellent stability under strong ultraviolet light (nm), reducing control costs. The resulting white light demonstrates moderate color reproduction, and its stability is sufficient to meet color reproduction requirements. The regulated color is stable and does not fluctuate unpredictably, making it suitable for use in optical devices. All the white phosphors described above can be used for information encryption, showcasing their potential applications in areas such as anti-counterfeiting luminescent paper and optical devices.

[0014] The beneficial effects of this invention are as follows: (1) The novel rare earth co-doped complex prepared by this invention has dual emission characteristics under single excitation, and can be used to manufacture Tb for glare-free white light-emitting diodes. 3+ Eu 3+ This rare-earth co-doped complex, doped with a yellow phosphor, exhibits a large Stokes shift, effectively converting violet excitation light into yellow emission. Mixing it with different proportions of triphenylamine allows for chromaticity adjustment from orange-yellow to white light, including the creation of an ideal warm white light with CIE coordinates of (0.3312, 0.3557) and (0.3137, 0.3305). Compared to previous methods of adjusting white light using red, green, and blue primary colors, this method not only reduces the difficulty of white light adjustment but also largely solves the problem of color temperature instability caused by different light decay in three-primary-color combinations. The adjusted white light exhibits moderate color reproduction, and the phosphor's stability meets the requirements for color reproduction. The adjusted color is very stable and does not fluctuate wildly, making it suitable for use as an optical device. The adjusted white phosphor can be used for information encryption, demonstrating the potential applications of these materials in anti-counterfeiting luminescent paper and optical devices.

[0015] (2) The synthesis process of this invention is simple, low-cost, efficient and reproducible. It can be applied to industrial production. The selection of the main ligand can be changed, and other ligands available on the market or newly synthesized can be used for synthesis. The blue dye triphenylamine used to adjust white light can also be changed. As long as the material emits blue light under ultraviolet light, it can be used to adjust the white light of rare earth co-doped complexes. Attached Figure Description

[0016] Figure 1 The diagram shows the basic structural unit of rare earth co-doped complexes. Figure 2 The diagram shows a 2D packing diagram of the basic building blocks of rare earth co-doped complexes. Figure 3 The image shows the fluorescence spectrum of the rare earth co-doped complex; Figure 4 The fluorescence spectra of the rare earth co-doped complexes prepared in Example 1 and Comparative Examples 1-4 are shown. Figure 5 The image shows the fluorescence emission spectra of Example 1 mixed with five different proportions of triphenylamine phosphor at 375 nm. Figure 6 The image shows the fluorescence emission spectra of Example 1 mixed with five different proportions of triphenylamine phosphor at 375 nm. Figure 7 The image shows a UV photograph of a thin film made by fusing five different proportions of powders with agarose gel under 375nm UV light. Detailed Implementation

[0017] The following will provide a clear and complete description of the concept and technical effects of the present invention in conjunction with the embodiments and accompanying drawings, so as to fully understand the purpose, solution and effects of the present invention. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0018] Example 1 like Figure 1-6 As shown, a rare earth co-doped complex material is provided, and its preparation method includes the following steps: S1. Dissolve 5.10 mg of terbium nitrate hexahydrate and 0.34 mg of europium nitrate hexahydrate in 0.5 mL of DMF and mix to obtain mixed solution A; S2. Place 7.42 mg of N,N-bis(4-carboxy)phenyl-3,5-bistrifluoromethylaniline in a beaker, add 0.5 mL of DMAC, and sonicate to mix well to obtain mixed solution B. Then slowly add it dropwise to mixed solution A obtained in step S1 to obtain mixed solution C. S3. Place 4.76 mg of 1,10-o-phenanthroline in a beaker, add 0.5 mL of DMAC, and sonicate to mix well to obtain mixed solution D. Then slowly add it dropwise to mixed solution C obtained in step S2 to obtain mixed solution E. Add 4 mL of acetonitrile and 4 mL of water to E, and sonicate to obtain mixed solution F. S4. The obtained mixed solution F was placed in a 10.0 mL flask and reacted in an oven at 80 °C for 3 days. After cooling to room temperature, 3.0 mg of crystals were obtained, which is the rare earth co-doped complex [Ln2(BTDB)3(DMA)2(phen)]. n Where, Ln = Tb 3+ Eu 3+ Furthermore, there are 183 Tb ions out of every 200 rare earth ions. 3+ 17 Eu 3+ , denoted as Tb 1.83 Eu 0.17 MOF.

[0019] Example 2 A rare earth co-doped complex material (1-Tb) 1.83 Eu 0.17 MOF was prepared using the same method as in Example 1, yielding 2.6 mg of crystals, denoted as 1-Tb. 1.83 Eu 0.17 MOF.

[0020] Example 3 A rare earth co-doped complex material (2-Tb) 1.83 Eu 0.17 The preparation method of MOF is as follows: The only difference is that in S1, "5.10 mg terbium nitrate hexahydrate and 0.34 mg europium nitrate hexahydrate dissolved in 0.5 mL DMF" is changed to "6.82 mg terbium trifluoromethanesulfonate and 0.45 mg europium trifluoromethanesulfonate dissolved in 0.5 mL DMF". The other steps are the same as in Example 1, yielding 2.8 mg of crystals, denoted as 2-Tb. 1.83 Eu 0.17 MOF.

[0021] Example 4 A rare earth co-doped complex material (3-Tb) 1.83 Eu 0.17 MOF was prepared using the same method as in Example 3, yielding 2.8 mg of crystals, denoted as 3-Tb. 1.83 Eu 0.17 MOF.

[0022] Comparative Example 1 A rare earth co-doped complex material is prepared by the following steps: S1. Dissolve 5.31 mg of terbium nitrate hexahydrate and 0.13 mg of europium nitrate hexahydrate in 0.5 mL of DMF and mix to obtain mixed solution A; S2. Place 7.42 mg of N,N-bis(4-carboxy)phenyl-3,5-bistrifluoromethylaniline in a beaker, add 0.5 mL of DMAC, and sonicate to mix well to obtain mixed solution B. Then slowly add it dropwise to mixed solution A obtained in step S1 to obtain mixed solution C. S3. Place 4.76 mg of 1,10-o-phenanthroline in a beaker, add 0.5 mL of DMAC, and sonicate to mix well to obtain mixed solution D. Then slowly add it dropwise to mixed solution C obtained in step S2 to obtain mixed solution E. Add 4 mL of acetonitrile and 4 mL of water to E, and sonicate to obtain mixed solution F. S4. The obtained mixed solution F was placed in a 10.0 mL flask and reacted in an oven at 80 °C for 3 days. After cooling to room temperature, 2.4 mg of crystals were obtained, which is the rare earth co-doped complex [Ln2(BTDB)3(DMA)2(phen)]. n Where, Ln = Tb 3+ Eu 3+ Furthermore, 190 out of every 200 rare earth ions are Tb. 3+ 10 Eu 3+ , denoted as Tb 1.90 Eu 0.10 MOF.

[0023] Comparative Example 2 A rare earth co-doped complex material (Tb 1.70 Eu 0.30 MOF was prepared by adjusting the step in Comparative Example S1 from "5.31 mg terbium nitrate hexahydrate and 0.13 mg europium nitrate hexahydrate dissolved in 0.5 mL DMF" to "4.78 mg terbium nitrate hexahydrate and 0.66 mg europium nitrate hexahydrate dissolved in 0.5 mL DMF". The other steps were the same as in Comparative Example 1, yielding 2.8 mg of crystals, denoted as Tb. 1.70 Eu 0.30 MOF.

[0024] Comparative Example 3 A novel rare earth co-doped complex material (Tb 1.60 Eu 0.40MOF was prepared by adjusting the step in Comparative Example S1 from "5.31 mg terbium nitrate hexahydrate and 0.13 mg europium nitrate hexahydrate dissolved in 0.5 mL DMF" to "4.48 mg terbium nitrate hexahydrate and 0.96 mg europium nitrate hexahydrate dissolved in 0.5 mL DMF". The other steps were the same as in Comparative Example 1, yielding 2.5 mg of crystals, denoted as Tb. 1.60 Eu 0.40 MOF.

[0025] Comparative Example 4 A rare earth co-doped complex material (Tb 1.50 Eu 0.50 MOF was prepared by adjusting the step in Comparative Example S1 from "5.31 mg terbium nitrate hexahydrate and 0.13 mg europium nitrate hexahydrate dissolved in 0.5 mL DMF" to "4.17 mg terbium nitrate hexahydrate and 1.27 mg europium nitrate hexahydrate dissolved in 0.5 mL DMF". The other steps were the same as in Comparative Example 1, yielding 2.5 mg of crystals, denoted as Tb. 1.50 Eu 0.50 MOF.

[0026] (1) The crystal structure of the rare earth co-doped complex prepared in Example 1 was determined. like Figure 1 and Figure 2 As shown, the novel rare-earth co-doped complex prepared in Example 1 crystallizes in the triclinic crystal system with space group . P- 1. Unit cell parameters: a = 9.4235(2) Å, b = 16.7101(4) Å, c = 27.7930(7) Å, α = 101.701(2)°, β = 94.212(2)°, γ = 93.322(2)°, V = 4262.02(18) Å 3 The chemical formula of the mononuclear rare-earth co-doped complex prepared in this invention is: [Ln2(BTDB)3(DMA)2(phen)] n Wherein, Ln is a trivalent rare earth ion.

[0027] The basic structural unit of this rare earth co-doped complex is a tetranuclear rare earth co-doped complex. Each tetranuclear rare earth co-doped complex molecule is bonded to each other through van der Waals forces. The basic structural unit is a neutral structural unit constructed from four crystallographically independent Ln, seven BTDB ligands, two 1,10-phenanthroline, and two DMA molecules. In the basic structural unit, there are 28 fully coordinated oxygen atoms in the seven BTDB ligands. Ln adopts octagonal and nine-coordinate modes. The carboxylic acid group of the ligand N,N-bis(4-carboxy)phenyl-3,5-bis(trifluoromethylaniline) adopts both bridging and chelating coordination modes with Ln. The N in the auxiliary ligand phenanthroline is chelated with Ln, and the O in the DMA is bridged with Ln. The bond lengths of Tb-O and Eu-O are between 2.282(4) and 2.802(5) Å, and the bond lengths of Tb-N and Eu-N are between 2.599(6) and 2.631(6) Å.

[0028] (2) The rare earth co-doped complexes prepared in Example 1 were tested by ICP-MS. The test results are shown in Table 1.

[0029] Table 1 As shown in Table 1, the novel rare earth co-doped complex [Ln2(BTDB)3(DMA)2(phen)] prepared in Example 1... n Wherein, Ln is a trivalent rare earth ion, Ln = Tb 3+ Eu 3+ Furthermore, there are 183 Tb ions out of every 200 rare earth ions. 3+ 17 Eu 3+ It contains 91.5% Tb(III) tetranuclear complex [Tb2(BTDB)3(DMA)2(phen)] by molar percentage. n And 8.5% of the Eu(III) mononuclear complex [Eu2(BTDB)3(DMA)2(phen)] n .

[0030] (3) The white light modulation of rare earth co-doped complexes was tested, and the method is as follows: Take 5 portions of 22.20 mg Tb prepared in Example 1. 1.83 Eu 0.17 Place the MOF into a small beaker and press 1(Tb) into each beaker. 1.83 Eu 0.17 MOF: 4 (triphenylamine), 1:8, 1:12, 1:16, 1:20. After being mixed thoroughly with triphenylamine at different molar ratios, the fluorescence spectra were measured using an excitation wavelength of 380 nm. Figure 5 ) Create a CIE chromaticity diagram ( Figure 6The chromaticity coordinates obtained by adjusting the powder in five different proportions were (0.3694, 0.4116) (1:4), (0.3564, 0.3946) (1:8), (0.3425, 0.3764) (1:12), (0.3312, 0.3557) (1:16), and (0.3137, 0.3305) (1:20). The CIE coordinates of the ideal warm white light and white light were (0.3312, 0.3557) and (0.3137, 0.3305), respectively. The powders mixed in the above five proportions were fused with agarose gel to form thin films, and the results were photographed under the illumination of a 365nm ultraviolet light. Figure 7 ).

[0031] The white light regulated by this invention exhibits moderate color reproduction, and the stability of the phosphor is sufficient to meet the requirements for color reproduction. The regulated color is very stable and does not exhibit unpredictable variations. Furthermore, the selected blue dye triphenylamine used for white light regulation can be changed. Any material that emits blue light under ultraviolet light can be used to regulate the white light of rare-earth co-doped complexes. That is, any proportion of Tb-Eu co-doped complexes exhibiting dual rare-earth center fluorescence emission under single excitation, combined with blue light-emitting materials, can regulate white light.

[0032] Although the description of the invention has been quite detailed and particularly of several described embodiments, it is not intended to limit it to any of these details or embodiments or any particular embodiment, but should be considered as providing a broad possible interpretation of the claims by referring to the appended claims and taking into account the prior art, thereby effectively covering the intended scope of the invention. Furthermore, the invention has been described above with respect to embodiments foreseeable by the inventors in order to provide a useful description, and non-substantial modifications to the invention that have not yet been foreseen may still represent equivalent modifications.

Claims

1. A rare earth co-doped complex material, characterized in that, The rare earth co-doped complex material is formed by sequentially stacking basic structural units through van der Waals interactions. The basic structural unit is a tetranuclear rare earth complex with the chemical formula [Ln2(BTDB)3(DMA)2(phen)]n, where Ln is a trivalent rare earth ion, Ln = Tb3+, Eu3+, and there are 183 Tb3+ and 17 Eu3+ ions per 200 rare earth ions; BTDB is N,N-bis(4-carboxy)phenyl-3,5-bistrifluoromethylaniline. The DMA is dimethylacetamide; The phen is 1,10-phenanthroline; The rare earth co-doped complex material is crystallized in a triclinic system with space group P-1 and cell parameters: a = 9.4234(2)~9.4236(2) Å, b = 16.6721(4)~16.7480(4) Å, c = 27.7905(7)~27.7954(7) Å, α = 101.544(2)~101.857(2)°, β = 94.166(2)~94.257(2)°, γ = 93.113(2)~93.531(2)°, V = 4252.91(15)~4271.12(18) Å3, Z =2.

2. The rare earth co-doped complex material according to claim 1, characterized in that, The basic structural unit is a neutral structural unit constructed from four crystallographically independent Ln molecules, seven BTDB ligands, two 1,10-phenanthroline molecules, and two DMA molecules. Among the seven BTDB ligands, there are 28 fully coordinated oxygen atoms. The Ln molecules adopt octagonal and nintagonal coordination modes. The BTDB ligands adopt both bridging and chelating coordination modes with Ln. The N in the auxiliary ligand 1,10-phenanthroline is chelated with Ln, and the O in the DMA is bridged with Ln. The bond lengths of Tb-O and Eu-O are between 2.282(4) and 2.802(5) Å, and the bond lengths of Tb-N and Eu-N are between 2.599(6) and 2.631(6) Å.

3. A method for preparing a rare earth co-doped complex material according to any one of claims 1-2, characterized in that, Includes the following steps: (a) Dissolve a soluble terbium salt and a soluble europium salt in a first solvent, mix well, and obtain a mixed solution A; the first solvent is DMF; (b) N,N-bis(4-carboxy)phenyl-3,5-bistrifluoromethylaniline was added to the second solvent and mixed well to obtain mixed solution B; the second solvent was DMA; (c) Add the obtained mixed solution B to mixed solution A to obtain mixed solution C; (d) Add 1,10-o-phenanthroline to a third solvent and mix well to obtain a mixed solution D; the third solvent is DMA; (e) Add the obtained mixed solution D to mixed solution C to obtain mixed solution E; (f) Add the obtained mixed solution E to the fourth solvent and mix well to obtain mixed solution F; the fourth solvent is water and acetonitrile; (g) The obtained mixed solution F is reacted at 70 ℃-90 ℃ to obtain rare earth co-doped complex material; The molar ratio of the N,N-bis(4-carboxy)phenyl-3,5-bis(trifluoromethyl)aniline, the soluble terbium salt, and the soluble europium salt is 21:15:

1.

4. The preparation method according to claim 3, characterized in that, The soluble terbium salt is any one of terbium nitrate, terbium chloride, terbium acetate, terbium sulfonate, terbium oxalate, and terbium trifluoromethanesulfonate.

5. The preparation method according to claim 3, characterized in that, The soluble europium salt is any one of europium nitrate, europium chloride, europium acetate, europium sulfonate, europium oxalate, and europium trifluoromethanesulfonate.

6. The preparation method according to claim 3, characterized in that, In step (g), the reaction time is 2 to 6 days.

7. The application of the rare earth co-doped complex material according to claim 1 in anti-counterfeiting luminescent paper and / or optical devices.

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