Light-emitting crystal material, preparation method and application thereof, and laser preformed light-emitting device

Abstract

This invention belongs to the field of organic electroluminescence technology, specifically relating to a luminescent crystal material, its preparation method and application, and laser-prefabricated luminescent devices. The preparation method of the luminescent crystal material includes the following steps: a first reaction is carried out with an amino-containing spirodifluorene monomer, a halogenated nitrogen heterocyclic compound, and a fluorinated organic acid to obtain a first intermediate; the first intermediate undergoes a second reaction with a gallium halide to obtain a second intermediate; a third reaction is carried out with a carbazole derivative, a naphthenic acid derivative, a luminescent bandgap modulating organic compound, and the second intermediate to obtain a third intermediate; the third intermediate is dissolved in an organic solvent for a fourth reaction, followed by multi-directional condensation separation; the material is collected in a pre-designed receiving dish in a 90-110°C condensation zone, and then subjected to a fourth post-processing to obtain the luminescent crystal material. The prepared luminescent crystal material exhibits high quantum efficiency, excellent thermal stability, and achieves balanced red, green, and blue performance.

Description

Technical Field

[0001] This invention belongs to the field of organic electroluminescence technology, specifically relating to a luminescent crystal material, its preparation method and application, and laser-prefabricated luminescent devices. Background Technology

[0002] Organic light-emitting diode (OLED) technology has become the core of next-generation display and lighting technology due to its advantages such as self-illumination, wide viewing angle, and flexibility. Its performance is highly dependent on the efficiency, color purity, thermal stability, and processability of the light-emitting layer material.

[0003] First-generation phosphors utilize small-molecule luminescent materials. Second-generation phosphors primarily produce red and green luminescent materials, exhibiting high internal quantum efficiency, higher brightness than phosphors, and relatively superior lifetime. However, they require doping with precious metals such as iridium (iridium, platinum, europium, osmium), making guest material fabrication challenging. The evaporation, photolithography, and printing equipment used in the production processes of first-generation phosphors and second-generation phosphors are all extremely expensive. Third-generation TADF materials are a novel luminescent material under research. TADF materials offer advantages such as high efficiency, reduced purification difficulty, and lower pixel deposition process costs. However, they cannot meet future commercialization requirements for simultaneous production of the three primary colors. TADF materials show improved lifetimes in red and yellow materials, reaching up to 10,000 hours, and in green materials, the lifetime limit is around 5,000 hours. However, blue materials remain uncommercially viable, with a lifetime limit of approximately 2,000 hours. The RGB color performance of blue materials does not significantly improve upon that of phosphors and phosphors, and adjustments to the half-width at half-maximum (WWHM) affect other material properties. Currently, only TADF (Temperature-Based Fluorescent) materials are commercially available, exhibiting considerable internal quantum efficiency. However, to address the significant intermolecular interactions and exciton quenching effects caused by the highly polar organic push-pull electron system, a host-guest structure is necessary. Ultimately, the similarity between host and guest excited states leads to extremely short lifetimes, preventing commercialization. The so-called "fourth-generation" hyperfluorescence (HF) materials (red, green, and blue) are essentially TADF materials with an additional fluorescent layer. Energy transfer maximizes internal quantum efficiency, but red, green, and blue materials have extremely short lifetimes. To address lifetime and half-width issues, doping with more difficult-to-prepare elements like deuterium is necessary. While quantum dot materials (CdSe, InP, nano-carbon, perovskites, etc.) and hydrogen isotope-doped materials have made significant progress in electroluminescence, their large bulk surface area and strong quantum fluorescence quenching effects limit their commercial value, primarily limiting their application to quantum tracking in the life sciences. The photoluminescence properties of quantum dot materials allow them to function as passive light emitters, such as in quantum dot films for LCD backlighting and maskless photolithography for blue OLED displays. However, this remains a niche market, with limitations in both cost and performance. Hydrogen isotope doping technology, primarily based on phosphor technology, suffers from performance instability and the extraction of necessary materials, hindering its industrialization.

[0004] Therefore, there is an urgent need to study a luminescent material that has excellent quantum efficiency, excellent thermal stability, and can achieve a balance of red, green and blue performance. Summary of the Invention

[0005] The purpose of this invention is to address the issues of efficiency, cost, and balance of full-color performance in existing luminescent materials by providing a luminescent crystal material, its preparation method, applications, and laser-prefabricated luminescent devices. This luminescent crystal material exhibits high quantum efficiency, excellent thermal stability, and can achieve a balance of red, green, and blue performance.

[0006] To achieve the above objectives, the first aspect of the present invention provides a method for preparing a luminescent crystal material, comprising the following steps: S1. In the presence of an aprotic solvent and a catalyst, an amino-containing spirodifluorene monomer, a halogenated nitrogen heterocyclic compound, and a fluorinated organic acid are subjected to a first reaction, followed by a first post-treatment to obtain a first intermediate. S2. In the presence of an alcohol solvent, the first intermediate is reacted with a gallium halide in a second reaction, followed by a second post-processing to obtain the second intermediate. S3. In the presence of alkaline ionic liquid and tetra(triphenylphosphine)palladium, carbazole derivative, naphthaleneboronic acid derivative, luminescence bandgap modulating organic compound and second intermediate undergo a third reaction, followed by a third post-treatment to obtain the third intermediate. S4. The third intermediate is dissolved in an organic solvent, and then a fourth reaction is carried out in the presence of palladium acetate and tris(o-methylphenyl)phosphine. After the fourth reaction is completed, multi-directional condensation separation is performed. The material in the condensation zone at 90-110℃ is collected in a pre-designed receiving dish as the crude material of the luminescent crystal. Then, a fourth post-processing is performed to obtain the luminescent crystal material.

[0007] The luminescent crystal material prepared in this invention has excellent thermal stability and thin film morphology stability, and can achieve a thin film photoluminescence quantum yield (PLQY) of over 90% and an internal quantum efficiency (IQE) of nearly 100%. Furthermore, devices using this luminescent crystal material not only achieve high external quantum efficiency (EQE), but also exhibit extremely low efficiency roll-off and ultra-long lifetime. This may be because: First, in this invention, an amino-containing spirodifluorene monomer is used as the core, and a rigid framework with a "rotational bisfluorene polymer" as the main chain is constructed through the first reaction, giving the luminescent crystal material excellent thermal stability. Then, a halogenated nitrogen heterocyclic compound is introduced to provide sites for subsequent metal coordination. Gallium ions are further introduced through the second reaction to form stable gallium ligand centers. In the third reaction, under the catalysis of an alkaline ionic liquid, luminescent functional groups such as carbazole derivatives, naphthaleneboronic acid derivatives, and specific luminescence bandgap modulating organic compounds are covalently bonded to preset sites around the main chain through Suzuki coupling. These functional groups are uniformly arranged around the spirodifluorene unit, which acts as a stereoblocking group, in a circumferential and helical dendritic form. Finally, through polymerization and multi-directional condensation separation and purification in the fourth reaction, a polymer of medium molecular weight is obtained. This allows the circumferential and helical blocking groups in the final luminescent crystal material to effectively inhibit molecular chain aggregation and quenching of the luminescent center.

[0008] Preferably, the amino-containing spirodifluorene monomer is selected from 2-amino-3-bromo-9,9-spirodifluorene (CAS No.: 2131825-24-4) and / or 2,2'-diamino-9,9'-spirodifluorene (CAS No.: 67665-45-6), and more preferably 2-amino-3-bromo-9,9-spirodifluorene.

[0009] Preferably, the halogenated nitrogen heterocyclic compound is selected from methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate (CAS No.: 1150164-88-7).

[0010] Preferably, the fluorinated organic acid is selected from trifluoroacetic acid and / or trifluoromethanesulfonic acid, and more preferably trifluoroacetic acid.

[0011] Preferably, the aprotic solvent is selected from N-methylpyrrolidone and / or N,N-dimethylformamide, and more preferably N-methylpyrrolidone.

[0012] Preferably, the catalyst is selected from tetrabutylammonium bromide.

[0013] Preferably, the molar ratio of the amino-containing spirodifluorene monomer to the halogenated nitrogen heterocyclic compound is 1:(1.5-3), more preferably 1:(2-2.5).

[0014] Preferably, the mass ratio of the fluorinated organic acid to the total mass of the amino-containing spirodifluorene monomer and the halogenated nitrogen heterocyclic compound is (1-1.5):1.

[0015] Preferably, the total mass ratio of the amino-containing spirobifluorene monomer and the halogenated nitrogen heterocyclic compound to the aprotic solvent is 1:(5-10).

[0016] Preferably, the total mass ratio of the amino-containing spirobifluorene monomer and the halogenated nitrogen heterocyclic compound to the catalyst is 1:(0.03-0.04).

[0017] Preferably, the first reaction is carried out in the presence of a weak acid salt. A weak acid salt is a salt formed by the neutralization reaction of a weak acid with a strong base. More preferably, the weak acid salt is selected from at least one of sodium acetate, potassium acetate, sodium formate, and potassium formate, preferably sodium acetate; more preferably, the mass ratio of the weak acid salt to the fluorinated organic acid is 1:(8-10).

[0018] In this invention, the inventors discovered that the luminescent crystal material prepared in the presence of a weak acid salt exhibits superior performance. This is presumably because the addition of the weak acid salt can partially neutralize the excess strong acid in the reaction system, making the reaction system milder. This ensures higher selectivity in the reaction between amino groups and quinoline hydroxyl groups / halogens, and allows for better construction of a spiral dendritic molecular structure. Consequently, the crystal material itself or its applications exhibit excellent thermal stability, high luminous efficiency, low efficiency roll-off, and ultra-long device lifespan.

[0019] Preferably, in step S1, the conditions for the first reaction include: a vacuum degree of 10 Pa to 20 Pa, a reaction temperature of 135 to 150 °C, and a reaction time of 5 to 8 hours.

[0020] The first reaction in step S1 of the present invention can be carried out in a reaction vessel well known in the art, such as a Schlenk flask.

[0021] Preferably, in step S1, the first post-processing method includes: precipitation, filtration, washing, drying, column chromatography, and removal of eluent. The aforementioned first processing method can be a conventional purification method in the art. For example, precipitation can be performed in water, followed by filtration, washing with water 3-5 times, washing with ethanol 3-5 times, and drying at 60-70°C to constant weight to obtain a crude product. The crude product is then dissolved in dichloromethane (the amount of dichloromethane should be as small as possible, just enough to completely dissolve the crude product), and purified by silica gel column chromatography. When using silica gel column chromatography, those skilled in the art can select appropriate eluents as needed. For example, petroleum ether and ethyl acetate are generally used for gradient washing, with the eluent ratio being: petroleum ether → petroleum ether / ethyl acetate = 4 / 1 (volume). The eluent fraction with Rf = 0.3-0.5 is collected as the target product fraction, then rotary evaporated to near dryness and vacuum dried at 65-75°C to constant weight to obtain the first intermediate.

[0022] Preferably, the alcohol solvent is selected from at least one of anhydrous ethanol, anhydrous isopropanol, and anhydrous n-butanol, and is preferably anhydrous n-butanol.

[0023] Preferably, the gallium-substituted halide is selected from at least one of gallium trifluoride trihydrate, gallium trichloride dihydrate, and gallium tribromide hexahydrate, and more preferably gallium trichloride dihydrate.

[0024] Preferably, the molar ratio of gallium to halogenated nitrogen heterocyclic compound in the gallium-substituted halide is 1:(1-4), more preferably 1:(1.5-2).

[0025] Preferably, the mass ratio of the alcohol solvent to the first intermediate is 1:(5-20), more preferably 1:(8-15).

[0026] Preferably, the second reaction is carried out in the presence of triethylamine, and more preferably, the mass ratio of triethylamine to the first intermediate is 1:(2-5), more preferably 1:(3-4).

[0027] Preferably, in step S2, the conditions for the second reaction include: being carried out under nitrogen protection, with a reaction temperature of 75-100°C and a reaction time of 8-15 hours.

[0028] Preferably, the second post-processing method includes: concentration, precipitation, filtration, water washing, drying, column chromatography, and removal of eluent; wherein, the aforementioned second processing method can be selected by those skilled in the art as needed. Specifically, concentration is to remove most of the alcohol solvent to obtain a concentrated solution, and rotary evaporation can be used for concentration. Precipitation is to precipitate the crude target product. The concentrate can be added to ice water at 0-5°C for precipitation. The amount of ice water is not particularly limited, generally 15-30 times the mass of the concentrate. The precipitated material is filtered to obtain a precipitate. After washing the precipitate with water 3-5 times, it is vacuum dried at 70-80°C to constant weight to obtain a crude product. Then, the crude product is dissolved in N,N-dimethylformamide, passed through a neutral alumina short column (Φ3×10cm), eluted with N,N-dimethylformamide, and the eluent is added to water to precipitate. After filtration, it is vacuum dried at 70-80°C to constant weight to obtain the second intermediate.

[0029] Preferably, the alkaline ionic liquid is selected from at least one of hydroxyl-1-methyl-3-butylimidazolium, hydroxyl-1-methyl-3-allylimidazolium, and 1-aminoethyl-3-methylimidazolium tetrafluoroborate, and more preferably 1-aminoethyl-3-methylimidazolium tetrafluoroborate.

[0030] In this invention, it was found that when 1-aminoethyl-3-methylimidazolium tetrafluoroborate is used as an alkaline ionic liquid, the resulting luminescent crystal material exhibits superior overall performance. This is presumably because the cations in 1-aminoethyl-3-methylimidazolium tetrafluoroborate can stabilize the active intermediate of tetra(triphenylphosphine)palladium through steric hindrance and electronic effects, thereby lowering the reaction energy barrier. Traditional inorganic bases do not possess this effect. Furthermore, the tetrafluoroborate anion enables the alkaline ionic liquid to promote the dissolution, contact, and mass transfer of reactants. Moreover, the alkaline ionic liquid can achieve efficient and clean separation from the product through simple water washing after the reaction, reducing metal residue and thus promoting the preparation of the final high-performance luminescent crystal material.

[0031] Preferably, the carbazole derivative is selected from 9-phenylcarbazole-3-boronic acid pinacol ester and / or 3,6-di-tert-butyl-1-boronic acid pinacol ester-9H-carbazole, and more preferably 9-phenylcarbazole-3-boronic acid pinacol ester.

[0032] In this invention, it was found that the luminescent crystal material prepared using 9-phenylcarbazole-3-boronic acid pinacol was more effective than that prepared using 3,6-di-tert-butyl-1-boronic acid pinacol ester-9H-carbazole. This is presumably because 9-phenylcarbazole-3-boronic acid pinacol not only optimizes the electronic structure but also introduces additional steric hindrance. In addition, the borate ester located at the 3-position of the carbazole can form effective conjugation with the spirodifluorene backbone and other acceptor units to the greatest extent, promoting efficient charge transfer luminescence. In contrast, the substituents and linkage sites of 3,6-di-tert-butylcarbazole borate ester may not match the electronic structure and spatial arrangement of the entire system, resulting in a decrease in the luminescence effect of the final luminescent crystal material.

[0033] Preferably, the naphthaleneboronic acid derivative is selected from 1-naphthaleneboronic acid and / or 2-naphthaleneboronic acid.

[0034] In this invention, the luminescence bandgap modulating organic material can be selected as needed, specifically according to the different linear emission wavelengths of different luminescent crystal materials. Preferably, the luminescence bandgap modulating organic material includes at least one of 3,7-di-tert-butyl-10H-phenthiazine, phenoxazine, and 4,7-bis(thiophen-2-yl)benzo[c][1,2,5]thiadiazole. Specifically, when the target emission on the luminescent crystal material is blue light, the luminescence bandgap modulating organic material is 3,7-di-tert-butyl-10H-phenthiazine; when the target emission on the luminescent crystal material is green light, the luminescence bandgap modulating organic material is phenoxazine; and when the target emission on the luminescent crystal material is red light, the luminescence bandgap modulating organic material is phenoxazine-4,7-bis(thiophen-2-yl)benzo[c][1,2,5]thiadiazole.

[0035] Preferably, the molar ratio of the carbazole derivative to the gallium halide is (1.5-5):1, more preferably (2-2.5):1.

[0036] Preferably, the molar ratio of the naphthaleneboronic acid derivative to the gallium halide is (1.5-5):1, more preferably (2-2.5):1.

[0037] Preferably, the molar ratio of the light-emitting bandgap modulating organic material to the gallium-substituted halide is 1:(2-10).

[0038] Preferably, the mass ratio of the alkaline ionic liquid to the total mass of the carbazole derivative, naphthaleneboronic acid derivative, luminescence bandgap modulating organic compound, and the second intermediate is (0.1-0.2):1.

[0039] Preferably, the mass ratio of the tetra(triphenylphosphine)palladium to the total mass of the carbazole derivative, naphthaleneboronic acid derivative, luminescence bandgap modulating organic compound, and the second intermediate is (0.01-0.02):1.

[0040] Preferably, in step S3, the conditions for the third reaction include: a vacuum degree of 10 Pa to 20 Pa, a reaction temperature of 150 to 165 °C, and a reaction time of 8 to 15 hours.

[0041] Preferably, the third post-processing method includes: water quenching, organic solvent extraction, concentration, column chromatography separation, and solvent removal; wherein, the aforementioned third post-processing method can be selected by those skilled in the art as needed. Specifically, 8-15 times the volume of deionized water is added to quench and extract the alkaline ionic liquid, followed by separation; the organic phase is extracted with water 2-3 times, dried with anhydrous magnesium sulfate, filtered, and concentrated by rotary evaporation to near dryness to obtain a crude liquid. The crude liquid is passed through two PLgel Mixed-C columns with tetrahydrofuran as the mobile phase at a rate of 3-6 mL / min, and fractions with a retention time of 38-45 minutes are collected. After rotary evaporation to near dryness, the fraction is vacuum dried at 65-75°C to constant weight to obtain the third intermediate.

[0042] Preferably, the organic solvent is selected from at least one of o-dichlorobenzene, xylene, and toluene, and is preferably xylene.

[0043] Preferably, the mass ratio of the third intermediate to the volume of the organic solvent is 0.1-0.3 g / mL.

[0044] Preferably, the mass of the palladium acetate is 0.2%-0.4% of the mass of the third intermediate.

[0045] Preferably, the mass of the tris(o-methylphenyl)phosphine is 0.3%-0.5% of the mass of the third intermediate.

[0046] Preferably, in step S4, the conditions for the fourth reaction include: being carried out under an argon atmosphere, at a reaction temperature of 120-150°C, and for a reaction time of 8-15 hours.

[0047] Preferably, in step S4, the multi-directional condensation separation includes at least three independently temperature-controlled condenser tubes with temperature ranges of 120-130℃, 90-110℃, and 70-80℃, respectively. In this invention, the material concentrated in the 90-110℃ condensation zone is a crude luminescent crystal material, wherein the target product has a molecular weight of approximately 15000-25000D, which is a medium molecular weight.

[0048] Preferably, the fourth post-processing method includes: rotary evaporating and concentrating the crude luminescent crystal material to near dryness, dissolving it in tetrahydrofuran to obtain a material with a concentration of 8-15 g / mL, extracting the material 3-6 times with an equal volume of ultrapure water, collecting the organic phase, and transferring the organic phase to a high-performance chromatography system. The chromatographic column is a bonded silica column. Under positive nitrogen pressure (0.3-0.8 MPa), gradient elution is performed (n-hexane → n-hexane / ethyl acetate (volume 4 / 1) → n-hexane / ethyl acetate (volume 2 / 1) → ethyl acetate), collecting the eluent fraction with Rf = 0.2-0.5, rotary evaporating and concentrating the eluent fraction to near dryness, then vacuum drying it to constant weight at 70-80℃, and finally grinding it under a nitrogen atmosphere to a powder with a particle size of less than 100 μm to obtain the luminescent crystal material.

[0049] In some embodiments of the present invention, the method for preparing the luminescent crystal material includes the following steps: S1. In a Schlenk flask, add 2-amino-3-bromo-9,9-spirodifluorene, methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate, trifluoroacetic acid, sodium acetate, tetrabutylammonium bromide, and N-methylpyrrolidone. Vacuum the mixture to 10-20 Pa, heat to 135-150°C, stir for 5-8 hours, cool, add water to precipitate, filter, wash 3-5 times with water and 3-5 times with ethanol, and dry at 60-70°C to constant weight to obtain the crude product. Dissolve the crude product in dichloromethane, purify by silica gel column chromatography (eluent: petroleum ether → petroleum ether / ethyl acetate = 4 / 1 (volume), collect the eluent fraction with Rf = 0.3-0.5 as the target product fraction), then rotary evaporate to near dryness and vacuum dry at 65-75°C to constant weight to obtain the first intermediate; The molar ratio of 2-amino-3-bromo-9,9-spirodifluorene to methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate is 1:(2-2.5), the mass ratio of trifluoroacetic acid to the total mass of 2-amino-3-bromo-9,9-spirodifluorene and methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate is (1-1.5):1, and the mass ratio of sodium acetate to trifluoroacetic acid is 1:(8-1). The total mass ratio of methyl 2-amino-3-bromo-9,9-spirodifluorene and methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate to N-methylpyrrolidone is 1:(5-10), and the total mass ratio of methyl 2-amino-3-bromo-9,9-spirodifluorene and methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate to tetrabutylammonium bromide is 1:(0.03-0.04). S2. In a reflux reaction apparatus, the first intermediate described above is mixed thoroughly with anhydrous n-butanol, triethylamine is added, and then gallium trichloride dihydrate is added under nitrogen protection. The mixture is heated to 75-100°C and refluxed for 8-15 hours. After the reaction is completed and cooled to room temperature, most of the n-butanol is removed by rotary evaporation to obtain a concentrate. The concentrate is added to 10-30 times its weight of ice water at 0-5°C for precipitation. The precipitate is then filtered to obtain a precipitate. After washing the precipitate with water 3-5 times, it is vacuum dried at 70-80°C to constant weight to obtain a crude product. The crude product is then... The product was dissolved in N,N-dimethylformamide, passed through a neutral alumina short column (Φ3×10cm), eluted with N,N-dimethylformamide, the eluent was added to water to precipitate, filtered, and then vacuum dried at 70-80℃ to constant weight to obtain the second intermediate; wherein, the molar ratio of gallium in gallium trichloride dihydrate to methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate was 1:(1.5-2), the mass ratio of anhydrous n-butanol to the first intermediate was 1:(8-15), and the mass ratio of triethylamine to the first intermediate was 1:(3-4); S3. In a reaction flask, add 9-phenylcarbazole-3-boronic acid pinacol, 1-naphthoic acid (and / or 2-naphthoic acid), the luminescence bandgap modulating organic compound, the above-mentioned second intermediate, 1-aminoethyl-3-methylimidazolium tetrafluoroborate, and tetra(triphenylphosphine)palladium. Vacuum the mixture to 10-20 Pa, heat to 150-165°C, and react for 8-15 hours. After the reaction, quench with 8-15 times the volume of deionized water and extract 1-aminoethyl-3-methylimidazolium tetrafluoroborate. Separate the liquid and extract the organic phase 2-3 times with water. Dry the phase with anhydrous magnesium sulfate, filter, and concentrate by rotary evaporation to near dryness to obtain the crude liquid. Pass the crude product through two PLgels. Using a mixed-C column with THF as the mobile phase at a flow rate of 3-6 mL / min, fractions with a retention time of 38-45 min were collected, then rotary evaporated to near dryness and vacuum dried at 65-75 °C to constant weight to obtain the third intermediate. The molar ratio of 9-phenylcarbazole-3-boronic acid pinacol to gallium trichloride dihydrate was (2-2.5):1; the molar ratio of 1-naphthoboric acid (and / or 2-naphthoboric acid) to gallium trichloride dihydrate was (2-2.5):1; the mass ratio of 1-aminoethyl-3-methylimidazolium tetrafluoroborate to the total mass of 9-phenylcarbazole-3-boronic acid pinacol, 1-naphthoboric acid (and / or 2-naphthoboric acid), the luminescence bandgap modulating organic compound, and the second intermediate was (0.1-0.2):1; the mass ratio of tetrakis(triphenylphosphine)palladium to the total mass of 9-phenylcarbazole-3-boronic acid pinacol, 1-naphthoboric acid (and / or 2-naphthoboric acid), the luminescence bandgap modulating organic compound, and the second intermediate was (0.1-0.2):1. The ratio of the total mass of the gap-regulating organic compound and the second intermediate is (0.01-0.02):1; when the target emission on the luminescent crystal material is blue light, the luminescent gap-regulating organic compound is 3,7-di-tert-butyl-10H-phenothiazine, and the molar ratio of 3,7-di-tert-butyl-10H-phenothiazine to gallium trichloride dihydrate is 1:(4-4.5); when the target emission on the luminescent crystal material is green light, the luminescent gap-regulating organic compound is phenoxazine, and the molar ratio of phenoxazine to gallium trichloride dihydrate is 1:(2.5-3); when the target emission on the luminescent crystal material is red light, the luminescent gap-regulating organic compound is phenoxazine 4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole, and the molar ratio of phenoxazine 4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole to gallium trichloride dihydrate is 1:(3-3.5).

[0050] S4. The third intermediate was dissolved in xylene to obtain a material with a concentration of 0.1-0.3 g / mL. Then, palladium acetate and tris(o-methylphenyl)phosphine were added under an argon atmosphere, and the temperature was raised to 120-150℃. After reacting for 8-15 hours, the reaction solution was sequentially passed through condensers at 120-130℃, 90-110℃, and 70-80℃ for multi-directional condensation separation. The material from the 90-110℃ condensation zone was collected in a pre-designed receiving dish as the crude luminescent crystal material. The crude luminescent crystal material was then concentrated to near dryness by rotary evaporation and dissolved in tetrahydrofuran to obtain a material with a concentration of 8-15 g / mL. The material was extracted 3-6 times with an equal volume of ultrapure water, and the organic phase was collected and transferred to a high-performance chromatography system. The chromatographic column was a bonded silica column. Under positive nitrogen pressure (0.3-0.8 MPa), gradient elution was performed (n-hexane → n-hexane / ethyl acetate (volume 4 / 1) → n-hexane / ethyl acetate (volume 2 / 1) → ethyl acetate). The eluent fraction with Rf = 0.2-0.5 was collected. The eluent fraction was concentrated to near dryness by rotary evaporation and then vacuum dried to constant weight at 70-80℃. After that, it was ground into powder with a particle size of less than 100 μm under a nitrogen atmosphere to obtain the luminescent crystal material. The mass of palladium acetate was 0.2%-0.4% of the mass of the third intermediate, and the mass of tris(o-methylphenyl)phosphine was 0.3%-0.5% of the mass of the third intermediate.

[0051] The second aspect of the present invention provides a luminescent crystal material prepared by the method for preparing the luminescent crystal material described in the first aspect of the present invention.

[0052] The third aspect of the present invention provides applications of the light-emitting crystal material described in the second aspect of the present invention, including printed OLED displays, flexible displays, lighting applications, and special displays.

[0053] A fourth aspect of the present invention provides a laser pre-fabricated light-emitting device, comprising: a light-emitting layer, wherein the light-emitting layer comprises the light-emitting crystal material described in the second aspect of the present invention.

[0054] Those skilled in the art can fabricate laser pre-embedded light-emitting devices as needed. For example, the structure of a laser pre-embedded light-emitting device includes a cathode, an anode, and the aforementioned light-emitting layer located between the cathode and the anode. Further, it also includes an electron transport layer located between the cathode and the light-emitting layer, a hole transport layer located between the anode and the light-emitting layer, an electron injection layer located between the cathode and the electron transport layer, and a hole blocking layer located between the light-emitting layer and the electron transport layer. Those skilled in the art can configure these as needed, and the present invention does not impose any special restrictions on them, so they will not be elaborated further. For example, the structure of a laser pre-embedded light-emitting device is: ITO (130nm) / PEDOT:PSS (40nm) / PVK (10nm) / EML (70nm) / TPBi (40nm) / LiF (1nm) / Al (100nm).

[0055] Compared with the prior art, the present invention has at least the following beneficial effects: 1. The luminescent crystal material in this invention is different from the existing mainstream host-guest doping system. It does not require a host material and can fundamentally avoid stability problems caused by energy level matching and doping uniformity between the host and guest materials. It has better stability and can simplify device structure design and process. Furthermore, the luminescent crystal material also has excellent thermal stability and light transmittance. Devices based on this material can still maintain low efficiency roll-off and long working life even at high external quantum efficiency.

[0056] 2. In this invention, the luminous color of the final luminescent crystal material can be controlled by adjusting the luminous bandgap of the organic material, thereby achieving high-performance full-color coverage from blue light to red light. That is, the inclusion of the luminescent crystal material can enable a single device to have the characteristics of blue, green and red light luminescent materials, or it can integrate high-performance red, green and blue three-primary-color light luminescent units in a single device.

[0057] 3. The luminescent crystal material system in this invention does not rely on doping with precious metals such as iridium and platinum, fundamentally eliminating dependence on scarce precious metal resources. This allows for a significant reduction in future material costs and a more secure and stable supply chain. Its single-matrix characteristics simplify the material synthesis and purification routes, greatly reducing the difficulty of preparing high-purity "guest" materials and the dependence on ultra-precision purification equipment, which is conducive to industrialization. Detailed Implementation

[0058] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0059] Example 1 Preparation of luminescent crystal materials: S1. In a Schlenk flask, add 2-amino-3-bromo-9,9-spirodifluorene, methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate, trifluoroacetic acid, sodium acetate, tetrabutylammonium bromide, and N-methylpyrrolidone. Vacuum the mixture to 15 Pa, heat to 142 °C, stir for 6.5 hours, cool, add water to precipitate, filter, wash 3 times with water and 5 times with ethanol, and dry at 65 °C to constant weight to obtain the crude product. Dissolve the crude product in dichloromethane, purify by silica gel column chromatography (eluent: petroleum ether → petroleum ether / ethyl acetate = 4 / 1 (volume), collect the eluent fraction with Rf = 0.35-0.48 as the target product fraction), then rotary evaporate to near dryness and vacuum dry at 70 °C to constant weight to obtain the first intermediate; The molar ratio of 2-amino-3-bromo-9,9-spirodifluorene to methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate is 1:2.23; the mass ratio of trifluoroacetic acid to the total mass of 2-amino-3-bromo-9,9-spirodifluorene and methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate is 1.2:1; the mass ratio of sodium acetate to trifluoroacetic acid is 1:9.4; the mass ratio of the total mass of 2-amino-3-bromo-9,9-spirodifluorene and methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate to N-methylpyrrolidone is 1:6.5; the mass ratio of the total mass of 2-amino-3-bromo-9,9-spirodifluorene and methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate to tetrabutylammonium bromide is 1:0.032. S2. In a reflux reaction apparatus, the first intermediate described above is mixed thoroughly with anhydrous n-butanol. Triethylamine is added, followed by the addition of gallium trichloride dihydrate under nitrogen protection. The mixture is heated to 88°C and refluxed for 12 hours. After the reaction is completed and cooled to room temperature, most of the n-butanol is removed by rotary evaporation to obtain a concentrate. The concentrate is added to 15 times its weight of ice water at 2°C for precipitation. The precipitate is then filtered to obtain a precipitate. After washing the precipitate four times with water, it is vacuum dried at 75°C to constant weight to obtain a crude product. The crude product is then treated with N... The N-dimethylformamide was dissolved and passed through a neutral alumina short column (Φ3×10cm). The solution was eluted with N,N-dimethylformamide, and the eluent was added to water to precipitate the product. After filtration, the product was vacuum dried at 70-80℃ to constant weight to obtain the second intermediate. The molar ratio of gallium in the gallium trichloride dihydrate to methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate was 1:1.83, the mass ratio of anhydrous n-butanol to the first intermediate was 1:12.4, and the mass ratio of triethylamine to the first intermediate was 1:3.2. S3. In a reaction flask, add 9-phenylcarbazole-3-boronic acid pinacol, 1-naphthoic acid, the luminescence bandgap modulating organic compound, the above-mentioned second intermediate, 1-aminoethyl-3-methylimidazolium tetrafluoroborate, and tetra(triphenylphosphine)palladium. Vacuum the mixture to 15 Pa, heat to 158 °C, and react for 10 hours. After the reaction, quench with 10 times the volume of deionized water and extract 1-aminoethyl-3-methylimidazolium tetrafluoroborate. Separate the liquid and extract the organic phase three times with water, dry with anhydrous magnesium sulfate, filter, and concentrate by rotary evaporation to near dryness to obtain the crude liquid. Pass the crude product through two PLgels. A mixed-C column was used with THF as the mobile phase at a flow rate of 5 mL / min to collect fractions with retention times of 39.5–44.2 min. The fractions were then rotary evaporated to near dryness and vacuum dried at 70 °C to constant weight to obtain the third intermediate. This intermediate contained a molar ratio of 9-phenylcarbazole-3-boronic acid pinacol to gallium trichloride dihydrate of 2.23:1, a molar ratio of 1-naphthoboronic acid (and / or 2-naphthoboronic acid) to gallium trichloride dihydrate of 2.23:1, and a mass ratio of 1-aminoethyl-3-methylimidazolium tetrafluoroborate to 9... The mass ratio of 9-phenylcarbazole-3-boronic acid pinacol, 1-naphthoboronic acid, the luminescence bandgap regulating organic compound, and the second intermediate is 0.12:1; the mass ratio of tetrakis(triphenylphosphine)palladium to the total mass of 9-phenylcarbazole-3-boronic acid pinacol, 1-naphthoboronic acid, the luminescence bandgap regulating organic compound, and the second intermediate is 0.18:1; the luminescence bandgap regulating organic compound is 3,7-di-tert-butyl-10H-phenothiazine, and the molar ratio of 3,7-di-tert-butyl-10H-phenothiazine to gallium trichloride dihydrate is 1:4.26; S4. The third intermediate was dissolved in xylene to obtain a material with a concentration of 0.23 g / mL. Then, palladium acetate and tris(o-methylphenyl)phosphine were added under an argon atmosphere, and the temperature was raised to 135℃. After reacting for 10 hours, the reaction solution was sequentially passed through condensers at 125±2℃, 100±2℃, and 75±2℃ for multi-directional condensation separation. The material collected in the 100±2℃ condensation zone in a pre-designed receiving dish was the crude luminescent crystal material. The crude luminescent crystal material was then concentrated to near dryness by rotary evaporation and dissolved in tetrahydrofuran to obtain a material with a concentration of 10 g / mL. The material was extracted five times with an equal volume of ultrapure water, and the organic phase was collected and transferred to a high-performance chromatography system. The chromatographic column was a bonded silica column. Under positive nitrogen pressure (0.5 MPa), gradient elution was performed (n-hexane → n-hexane / ethyl acetate (volume 4 / 1) → n-hexane / ethyl acetate (volume 2 / 1) → ethyl acetate). The eluent fraction with Rf = 0.25-0.4 was collected. The eluent fraction was concentrated to near dryness by rotary evaporation and then vacuum dried to constant weight at 75 °C. After that, it was ground into powder with a particle size of less than 100 μm under a nitrogen atmosphere to obtain the luminescent crystal material. The mass of palladium acetate was 0.32% of the mass of the third intermediate.

[0060] The optical crystal material is a blue luminescent crystal material with a target emission peak around 460nm.

[0061] Example 2 The method according to Example 1 differs in that: In step S3, heating to 158°C is replaced with heating to 152°C, and the organic material for controlling the light-emitting bandgap is phenoxazine, with a molar ratio of phenoxazine to gallium trichloride dihydrate of 1:2.85; In step S4, the temperature is changed from 135℃ to 128℃. The reaction solution is sequentially passed through condensers at 120±2℃, 95±2℃, and 70±2℃ for multi-directional condensation separation. The material collected in the 95±2℃ condensation zone in the pre-set receiving dish is the crude luminescent crystal material, and the elution fraction with Rf=0.3-0.45 is collected. The rest is similar to Example 1.

[0062] The optical crystal material is a green luminescent crystal material with a target emission peak around 530 nm.

[0063] Example 3 The method according to Example 1 differs in that: In step S3, 1-naphthoboric acid was replaced with 2-naphthoboric acid, and the reaction time was changed from 158°C for 10 hours to 162°C for 12 hours. The luminescence bandgap modulating organic compound was phenoxazine 4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole, and the molar ratio of phenoxazine 4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole to gallium trichloride dihydrate was 1:3.27. In step S4, the temperature is changed from 135℃ to 145℃. The reaction solution is sequentially passed through condensers at 130±2℃, 105±2℃, and 80±2℃ for multi-directional condensation separation. The material collected in the 105±2℃ condensation zone in a pre-designed receiving dish is the crude luminescent crystal material. Gradient elution is performed (n-hexane → n-hexane / ethyl acetate (volume 4 / 1) → n-hexane / ethyl acetate (volume 2 / 1) → n-hexane / ethyl acetate (volume 1 / 1) → ethyl acetate). The rest is similar to Example 1.

[0064] The optical crystal material is a red luminescent crystal material with a target emission peak around 620nm.

[0065] Comparative Example 1 The method according to Example 1 differs in that: In step S2, no triethylamine is present; The rest is similar to Example 1.

[0066] Comparative Example 2 The method according to Example 1 differs in that: In step S2, triethylamine is replaced with sodium dihydrogen phosphate; The rest is similar to Example 1.

[0067] Comparative Example 3 The method according to Example 1 differs in that: In step S3, 1-aminoethyl-3-methylimidazolium tetrafluoroborate is replaced with hydroxide 1-methyl-3-allylimidazolium; The rest is similar to Example 1.

[0068] Comparative Example 4 The method according to Example 1 differs in that: In step S3, 1-aminoethyl-3-methylimidazolium tetrafluoroborate is replaced with ammonium carbonate; The rest is similar to Example 1.

[0069] Comparative Example 5 The method according to Example 1 differs in that: In step S3, 9-phenylcarbazole-3-boronic acid pinacol is replaced with 3,6-di-tert-butyl-1-boronic acid pinacol ester-9H-carbazole; The rest is similar to Example 1.

[0070] Comparative Example 6 The method according to Example 1 differs in that: In step S4, the temperature is raised to 160℃, and after reacting for 10 hours, the reaction solution is sequentially passed through condensers at 130±2℃, 120±2℃, and 100±2℃ for multi-directional condensation separation. The material collected in the 120±2℃ condensation zone in the pre-set receiving dish is the crude material of the luminescent crystal. The rest is similar to Example 1.

[0071] Comparative Example 7 The method according to Example 1 differs in that: In step S4, the temperature is raised to 135℃, and after reacting for 10 hours, the reaction solution is sequentially passed through condensers at 100±2℃, 80±2℃, and 60±2℃ for multi-directional condensation separation. The material collected in the 80±2℃ condensation zone in the pre-set receiving dish is the crude material of the luminescent crystal. The rest is similar to Example 1.

[0072] Comparative Example 8 S1. In a Schlenk flask, add 2,7-dibromo-9,9-dioctylfluorene, N-phenylcarbazole-3-boric acid, tetra(triphenylphosphine)palladium, potassium carbonate, and a toluene / water mixture. Vacuum the mixture to 15 Pa, heat to 112 °C, stir for 12 hours, and then separate the layers. Extract the organic phase three times with water, dry with anhydrous magnesium sulfate, filter, and concentrate by rotary evaporation to near dryness to obtain the crude product. Dissolve the crude product in dichloromethane and purify it by silica gel column chromatography (eluent: petroleum ether → petroleum ether / dichloromethane = 1 / 1 (volume), collect the eluent fraction with Rf = 0.35-0.5 as the target product fraction). After being evaporated to near dryness, the product was vacuum dried at 60°C to constant weight to obtain the first monomer. The molar ratio of 2,7-dibromo-9,9-dioctylfluorene to N-phenylcarbazole-3-boronic acid was 1:2.3; the mass ratio of tetrakis(triphenylphosphine)palladium to the total mass of 2,7-dibromo-9,9-dioctylfluorene and N-phenylcarbazole-3-boronic acid was 0.016:1; the molar ratio of potassium carbonate to N-phenylcarbazole-3-boronic acid was 2.3:1; the volume ratio of the toluene / water mixed solvent was 4:1; and the mass ratio of the total mass of 2,7-dibromo-9,9-dioctylfluorene and N-phenylcarbazole-3-boronic acid to toluene was 1:10. S2. In a reaction flask, add the first monomer, bis(dibenzylacetone)palladium, tris(o-methylphenyl)phosphine, potassium carbonate, and xylene. Evacuate to 15 Pa, introduce argon, and heat to 140 °C for 24 hours. After the reaction, dropwise precipitate the mixture into methanol. Filter to obtain the precipitate, wash three times with methanol, and dry under vacuum at 65 °C to constant weight to obtain the crude product. Dissolve the crude product in tetrahydrofuran and pass it through two PLgel Mixed-C columns with THF as the mobile phase at a rate of 4 mL / min. Collect fractions with retention times of 35-42 minutes, then rotary evaporate to near dryness and dry under vacuum at 65 °C to constant weight to obtain the luminescent crystal material. The mass ratio of bis(dibenzylacetone)palladium to the first intermediate is 0.01:1, the mass ratio of tris(o-methylphenyl)phosphine to the first intermediate is 0.023:1, the molar ratio of potassium carbonate to the first intermediate is 1:1, and the mass ratio of xylene to the first intermediate is 5:1.

[0073] Comparative Example 9 Commercially available iridium complex phosphorescent material Ir(ppy)3 is used as a luminescent crystal material.

[0074] Performance testing 1. Thermal stability test: Thermogravimetric analyzer (nitrogen atmosphere, heating rate 10℃ / min) and differential scanning calorimeter (nitrogen atmosphere, heating rate 10℃ / min) were used to test the Td and Tg of the luminescent crystal materials in Examples 1-3 and Comparative Examples 1-9, respectively.

[0075] 2. Photophysical performance testing: The luminescent crystal materials from Examples 1-3 and Comparative Examples 1-9 were prepared into 10 mg / mL chlorobenzene solutions, filtered through 0.22 μm PTFE, spin-coated onto a 10 × 10 mm quartz substrate (1500 rpm / 30 s), annealed at 120 °C for 30 minutes, and then the film thickness was measured to be 80 ± 3 nm using an ellipsometry.

[0076] (1) The standard absolute method was used to measure the direct and indirect excitation spectra, and the photoluminescence quantum yield PLQY of the thin film was calculated after background subtraction. The excitation wavelength in Example 1 and Comparative Examples 1-9 was 375 nm, the excitation wavelength in Example 2 was 400 nm, and the excitation wavelength in Example 3 was 450 nm.

[0077] (2) The transmittance of the film at 550 nm was measured using a UV-Vis spectrophotometer.

[0078] (3) Emission peak wavelength (λ_pl): The maximum emission peak of the PL spectrum of the thin film. 3. Performance testing of laser-prefabricated light-emitting devices: The structure of the laser-prefabricated light-emitting device is: ITO (130nm) / PEDOT:PSS (40nm) / PVK (10nm) / EML (70nm) / TPBi (40nm) / LiF (1nm) / Al (100nm) Emissive Layer (EML) Fabrication: Solution formulation: The luminescent crystal materials in Examples 1-3 and Comparative Examples 1-8 were dissolved in chlorobenzene / anisole (volume ratio 7:3) to a total concentration of 6 wt%, with 0.1 wt% of Surfynol® 465 surfactant added; the solution formulation in Comparative Example 9 was: luminescent crystal material and 4,4-di(9-carbazole)biphenyl in a mass ratio of 1:3, with the luminescent crystal material and 4,4-di(9-carbazole)biphenyl dissolved in chlorobenzene / anisole (volume ratio 7:3), and the total concentration of the luminescent crystal material and 4,4-di(9-carbazole)biphenyl was 6 wt%.

[0079] Spin coating: 2000 rpm / 30s, anneal at 120℃ for 30 minutes Film thickness control: 80±2nm (Dektak step gauge).

[0080] Testing: The following tests were performed in a nitrogen atmosphere using a calibrated integrating sphere system: (1) Testing internal quantum efficiency (IQE): The efficiency of a laser pre-fabricated light-emitting device in converting injected electron-hole pairs into photons generated inside the device.

[0081] (2) Test the maximum external quantum efficiency (maximum EQE): the peak value of the EQE of the laser pre-fabricated light-emitting device.

[0082] (3) Efficiency roll-off: The calculated brightness is 1000 cd / m² 2 When the EQE is 1000, the efficiency roll-off is [1 - (EQE1000 / maximum EQE)] × 100%.

[0083] (4) Device lifespan (LT90): Initial luminance 1000 cd / m 2 The time it takes for the brightness to decrease to 95%.

[0084] The test results for thermal stability and photophysical properties are shown in Table 1.

[0085] The test results of the laser pre-fabricated light-emitting device are shown in Table 2.

[0086] Table 1 Test results of thermal stability and photophysical properties Table 2 Test results of laser prefabricated light-emitting devices The performance test results above show that the luminescent crystal materials prepared in Examples 1-3 not only possess excellent thermal stability and luminous efficiency, but also exhibit excellent device performance, such as a maximum EQE > 42% and a performance at 1000 cd / m². 2 The efficiency roll-off at various brightness levels is less than 3.5%, and it also has a long service life.

[0087] The comparative examples, lacking necessary technical solutions, showed significantly inferior performance compared to the examples. Specifically, Comparative Example 1 omitted triethylamine in the second step, while Comparative Example 2 replaced triethylamine with sodium dihydrogen phosphate, resulting in a substantial decrease in the PLQY and device lifetime of the luminescent crystal material compared to Example 1. Comparative Example 3 changed the type of alkaline ionic liquid, and Comparative Example 4 replaced the alkaline ionic liquid with a common inorganic base, leading to a decrease in the overall performance of the final luminescent crystal material. Comparative Example 5 replaced 9-phenylcarbazole-3-boronate pinacol ester with 3,6-di-tert-butylcarbazole borate ester, possibly due to a mismatch between the donor unit structure and electronic properties, resulting in a deterioration in the PLQY and efficiency roll-off of the final luminescent crystal material. Comparative Examples 6 and 7 altered the temperature setting for multi-directional condensation separation in the fourth step, possibly resulting in an inability to accurately obtain polymers within the target molecular weight range, significantly reducing the performance of the luminescent crystal material. Comparative Example 8 used a completely different traditional linear polymer synthesis route and monomers, resulting in materials with poor thermal stability, intrinsic luminous efficiency, and device performance.

[0088] The above experimental results further demonstrate the importance of the technical solution defined in this invention to its technical effect.

[0089] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a luminescent crystal material, characterized in that, Includes the following steps: S1. In the presence of an aprotic solvent and a catalyst, an amino-containing spirodifluorene monomer, a halogenated nitrogen heterocyclic compound, and a fluorinated organic acid are subjected to a first reaction, followed by a first post-treatment to obtain a first intermediate. S2. In the presence of an alcohol solvent, the first intermediate is reacted with a gallium halide in a second reaction, followed by a second post-processing to obtain the second intermediate. S3. In the presence of alkaline ionic liquid and tetra(triphenylphosphine)palladium, carbazole derivative, naphthaleneboronic acid derivative, luminescence bandgap modulating organic compound and second intermediate undergo a third reaction, followed by a third post-treatment to obtain the third intermediate. S4. The third intermediate is dissolved in an organic solvent, and then a fourth reaction is carried out in the presence of palladium acetate and tris(o-methylphenyl)phosphine. After the fourth reaction is completed, multi-directional condensation separation is performed. The material in the condensation zone at 90-110℃ is collected in a pre-designed receiving dish as the crude material of the luminescent crystal. Then, a fourth post-processing is performed to obtain the luminescent crystal material. The luminescence bandgap modulated organic compounds include at least one of 3,7-di-tert-butyl-10H-phenthiazine, phenoxazine, and 4,7-bis(thiophen-2-yl)benzo[c][1,2,5]thiadiazole.

2. The method for preparing the luminescent crystal material according to claim 1, characterized in that, The amino-containing spirodifluorene monomer is selected from 2-amino-3-bromo-9,9-spirodifluorene and / or 2,2'-diamino-9,9'-spirodifluorene; the halogenated nitrogen heterocyclic compound is selected from methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate; the fluorinated organic acid is selected from trifluoroacetic acid and / or trifluoromethanesulfonic acid; the aprotic solvent is selected from N-methylpyrrolidone and / or N,N-dimethylformamide; the catalyst is selected from tetrabutylammonium bromide; the amino-containing spirodifluorene monomer and halogenated nitrogen heterocyclic compound are selected from methyl 7-chloro-8-fluoro-4-hydroxyquinoline-2-carboxylate. The molar ratio of the nitrogen heterocyclic compound is 1:(1.5-3); the mass ratio of the fluorinated organic acid to the total mass of the amino-containing spirodifluorene monomer and the halogenated nitrogen heterocyclic compound is (1-1.5):1; the mass ratio of the total mass of the amino-containing spirodifluorene monomer and the halogenated nitrogen heterocyclic compound to the aprotic solvent is 1:(5-10); the mass ratio of the total mass of the amino-containing spirodifluorene monomer and the halogenated nitrogen heterocyclic compound to the catalyst is 1:(0.03-0.04).

3. The method for preparing the luminescent crystal material according to claim 1, characterized in that, The first reaction is carried out in the presence of a weak acid salt; in step S1, the conditions of the first reaction include: a vacuum degree of 10 Pa-20 Pa, a reaction temperature of 135-150 °C, and a reaction time of 5-8 hours; in step S1, the first post-treatment method includes: precipitation, filtration, washing, drying, column chromatography, and removal of eluent.

4. The method for preparing the luminescent crystal material according to claim 1, characterized in that, The alcohol solvent is selected from at least one of anhydrous ethanol, anhydrous isopropanol, and anhydrous n-butanol; the gallium halide is selected from at least one of gallium trifluoride trihydrate, gallium trichloride dihydrate, and gallium tribromide hexahydrate; the molar ratio of gallium to the halogenated nitrogen heterocyclic compound in the gallium halide is 1:(1-4); the mass ratio of the alcohol solvent to the first intermediate is 1:(5-20); the second reaction is carried out in the presence of triethylamine; in step S2, the conditions for the second reaction include: carried out under nitrogen protection, the reaction temperature is 75-100℃, and the reaction time is 8-15 hours.

5. The method for preparing the luminescent crystal material according to claim 1, characterized in that, The alkaline ionic liquid is selected from at least one of hydroxyl-1-methyl-3-butylimidazol, hydroxyl-1-methyl-3-allylimidazol, and 1-aminoethyl-3-methylimidazol tetrafluoroborate; the carbazole derivative is selected from 9-phenylcarbazole-3-boronate pinacol and / or 3,6-di-tert-butyl-1-boronate pinacol-9H-carbazole; the naphthaleneboronic acid derivative is selected from 1-naphthaleneboronic acid and / or 2-naphthaleneboronic acid; the molar ratio of the carbazole derivative to the gallium halide is (1.5-5):1; the molar ratio of the naphthaleneboronic acid derivative to the gallium halide is (… 1.5-5):1; The mass ratio of the alkaline ionic liquid to the total mass of the carbazole derivative, naphthaleneboronic acid derivative, luminescence bandgap regulating organic compound, and the second intermediate is (0.1-0.2):1; The mass ratio of the tetra(triphenylphosphine)palladium to the total mass of the carbazole derivative, naphthaleneboronic acid derivative, luminescence bandgap regulating organic compound, and the second intermediate is (0.01-0.02):1; In step S3, the conditions of the third reaction include: vacuum degree of 10Pa-20Pa, reaction temperature of 150-165℃, and reaction time of 8-15 hours.

6. The method for preparing the luminescent crystal material according to claim 1, characterized in that, The organic solvent is selected from at least one of o-dichlorobenzene, xylene, and toluene; the mass ratio of the third intermediate to the volume of the organic solvent is 0.1-0.3 g / mL; the mass of palladium acetate is 0.2%-0.4% of the mass of the third intermediate; and the mass of tris(o-methylphenyl)phosphine is 0.3%-0.5% of the mass of the third intermediate.

7. The method for preparing the luminescent crystal material according to claim 1, characterized in that, In step S4, the conditions for the fourth reaction include: being carried out under an argon atmosphere, with a reaction temperature of 120-150℃ and a reaction time of 8-15 hours; in step S4, the multi-directional condensation separation includes at least three independently temperature-controlled condenser tubes with temperature ranges of 120-130℃, 90-110℃, and 70-80℃, respectively.

8. A luminescent crystal material, characterized in that, The luminescent crystal material is prepared by the method for preparing the luminescent crystal material according to any one of claims 1-7.

9. The application of the luminescent crystal material according to claim 8, characterized in that, The applications include printed OLED displays, flexible displays, lighting, and special displays.

10. A laser pre-fabricated light-emitting device, characterized in that, include: The light-emitting layer comprises the light-emitting crystal material as described in claim 8.

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