Design, preparation and application of efficient organic co-crystals

Abstract

The application relates to a high-efficiency organic luminescent co-crystal design, preparation and application, a host-guest doped luminescent material taking iodine-substituted carbazole derivatives as the host and application of the luminescent material in scintillation crystals, strong electron-accepting molecules are used as electron acceptors, twisted structure triphenyl phosphine oxide derivatives are used as electron donors, and the organic luminescent co-crystal is prepared through a solution evaporation method. The donor and acceptor molecules are combined and assembled into organic luminescent co-crystals with more rigid structures and more compact arrangements through non-covalent bond interaction. The non-covalent bond interaction in the co-crystal, especially the intermolecular charge transfer, can make the energy gap between the singlet state and the triplet state narrow, improve the intersystem crossing rate, and improve the utilization rate of the triplet exciton, so that high-efficiency luminescence is realized. The application provides a new design strategy for the design and preparation of novel organic luminescent materials, and is suitable for organic light-emitting diodes (OLEDs).

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of organic light-emitting materials, and relates to a design, preparation and application of an efficient organic light-emitting co-crystal, in particular to a host-guest doped light-emitting material taking an iodine-substituted carbazole derivative as a host and application of the light-emitting material in a scintillation crystal. BACKGROUND

[0002] In recent years, organic co-crystal materials as functional light-emitting materials have attracted much attention [1-3] An organic light-emitting co-crystal is composed of multiple components and orderly arranged under the interaction of non-covalent bonds (hydrogen bonds, halogen bonds, pi-pi and charge transfer, etc.). Among them, the composition unit, intermolecular weak interaction and stacking mode will directly affect the light-emitting performance of the organic co-crystal. In the co-crystal system, the intermolecular interaction force can regulate the arrangement of the donor and the acceptor in space to adjust the light-emitting performance of the co-crystal, which avoids the complicated synthesis steps of the complex structure in the traditional organic light-emitting material. The regular and orderly arrangement in the co-crystal system is conducive to the study of the light-physical process of the co-crystal system. In addition, there are different molecular arrangement modes and a large number of intermolecular interactions in the co-crystal, which often produce significant changes to external stimuli (such as light, temperature, acid-base, stress), and have rich and sensitive sensing characteristics. This provides a material basis for preparing high-performance optical devices and provides a new choice for preparing the light-emitting layer of the OLED device.

[0003] An organic light-emitting co-crystal is composed of multiple components and orderly arranged, and the special molecular stacking and the synergistic effect between the components make the co-crystal material not only retain the inherent light-emitting properties of a single component, but also exhibit new light-emitting properties. At present, with the in-depth study of the organic light-emitting co-crystal, various functional light-emitting co-crystals such as organic room-temperature phosphor co-crystal, thermally activated delayed fluorescence co-crystal and multi-stimulus (temperature, force, light, acid-base, etc.) responsive co-crystal emerge in endlessly. The single-component light-emitting material has been widely studied and applied, while the multi-component doped light-emitting material is difficult to predict due to its amorphous state and uneven distribution. In comparison, the light-emitting of the multi-component co-crystal is not only simple to prepare, low in cost and easy to control the light-emitting performance, but also easier to study the light-emitting mechanism and explain the multi-functional light-emitting behavior through the orderly crystal arrangement.

[0004] In recent years, the organic co-crystal has achieved fruitful research results in the field of light emission, and has been extended to photoelectric response materials [4] , photovoltaic response materials [5] , nonlinear optical materials [6] , room-temperature phosphor materials [7] , stimulus-responsive materials [8]However, its design and preparation, luminescent properties and application are still the focus of researchers. For organic luminescent co-crystals, intermolecular interaction is the key to its assembly, so how to assemble into ordered co-crystals through intermolecular interaction is a challenge for the development of co-crystals. In addition, a reasonable and effective design strategy should be established to improve the preparation efficiency and repeatability of organic luminescent co-crystals, accurately adjust its luminescent properties, and play the advantages of co-crystals to promote its application in different fields. Therefore, it is of great significance to propose a reasonable design strategy to prepare efficient luminescent co-crystals, improve the preparation efficiency and repeatability, and promote the development and application of organic luminescent co-crystals. The present application proposes to realize the assembly between donors and acceptors by using the "twisted structure + intermolecular weak interaction binding site" of the donor molecule, and adjust the luminescent color and lifetime of the co-crystal. More intermolecular weak interaction binding sites can form a large number of intermolecular weak interactions, which is beneficial to the formation of co-crystals. Especially, the intermolecular charge transfer can narrow the energy gap between singlet and triplet states, improve the intersystem crossing rate, and improve the utilization rate of triplet excitons, so as to realize efficient luminescence, which is beneficial to its application in OLED.

[0005] [1] Park, S. K.; Cho, I.; Gierschner, J.; Kim, J. H.; Kim, J. H.; Kwon, J. E.; Kwon, O. K.; Whang, D. R.; Park, J. H.; An, B. K.; Park, S. Y., Stimuli-Responsive Reversible Fluorescence Switching in a Crystalline Donor-Acceptor Mixture Film: Mixed Stack Charge-Transfer Emission versus Segregated Stack Monomer Emission. Angew. Chem. Int. Ed. Engl. 2016, 55, 203-7.

[0006] [2] Li, S.; Yan, D., Two-Component Aggregation-Induced Emission Materials: Tunable One / Two-Photon Luminescence and Stimuli-Responsive Switches by Co-Crystal Formation. Advanced Optical Materials 2018, 6.

[0007] [3] Zhang, J.; Liu, G.; Zhou, Y.; Long, G.; Gu, P.; Zhang, Q., Solvent Accommodation: Functionalities Can Be Tailored Through Co-Crystallization Based on 1 : 1 Coronene-F4TCNQ Charge-Transfer Complex. ACS Applied Materials & Interfaces 2017, 9, 1183-1188.

[0008] [4] Li, Y.; Wang, W.; Leow, W. R.; Zhu, B.; Meng, F.; Zheng, L.; Zhu, J.; Chen, X., Optoelectronics of Organic Nanofibers Formed by Co-Assembly of Porphyrin and Perylenediimide. Small. 2014, 10, 2776-2781.

[0009] [5] Kang, S. J.; Ahn, S.; Kim, J. B.; Schenck, C; Hiszpanski, A. M.; Oh, S.; Schiros, T.; Loo, Y.-L.; Nuckolls, C, Using Self-Organization To Control Morphology in Molecular Photovoltaics. J. Am. Chem. Soc. 2013, 135, 2207-2212.

[0010] [6] Yan, D.; Yang, H.; Meng, Q.; Lin, H.; Wei, M., Two-Component Molecular Materials of 2,5-Diphenyloxazole Exhibiting Tunable Ultraviolet / Blue Polarized Emission, Pump-enhanced Luminescence, and Mechanochromic Response. Adv. Funct. Mater. 2014, 24, 587-594.

[0011] [7] Liu, K.; Li, S.; Fu, L.; Lei, Y.; Liao, Q.; Fu, H., Cocrystallization Tailoring Radiative Decay Pathways For Thermally Activated Delayed Fluorescence and Room-Temperature Phosphorescence Emission. Nanoscale. 2022, 14, 6305-6311.

[0012] [8] Sun, L.; Yang, F.; Zhang, X.; Hu, W., Stimuli-Responsive Behaviors of Organic Charge Transfer Cocrystals: Recent Advances and Perspectives. Mater. Chem. Front. 2020, 4, 715-728. SUMMARY

[0013] Technical problems to be solved

[0014] In order to avoid the shortcomings of the prior art, the present application provides an efficient design, preparation and application of organic luminescent cocrystals, a host-guest doped luminescent material based on iodine-substituted carbazole derivatives and its application in scintillation crystals.

[0015] The purpose of the present application is to provide an efficient organic luminescent cocrystal material, which is designed by the strategy of "twisted structure + intermolecular weak interaction binding site", changes the structure of the donor-acceptor, regulates the intermolecular interaction force, and realizes high-efficiency luminescence.

[0016] Another purpose of the present application is to provide a preparation method of the organic luminescent cocrystal material, which is simple, reproducible, efficient, and can be used to regulate the luminescent properties of the organic cocrystal material by selecting different donor-acceptor molecules.

[0017] The third purpose of the present application is to apply it to the field of organic light-emitting diodes and the like.

[0018] Technical scheme

[0019] A structure twisted triphenylphosphine oxide derivative, characterized in that the structural formula is:

[0020]

[0021] Wherein: R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, R19, R20, R21, R22, R23, R24, R25, R26, R27 and R28 in the structure are the same or different, each is independently selected from any one of hydrogen atom, alkyl, halogen, phenyl, alkoxy, nitro, amino, aldehyde group, cyano.

[0022] A preparation method of the twisted structure triphenyl phosphine oxide derivative, by increasing the steric hindrance of the molecule, different light-emitting groups are connected at the ortho position of the triphenyl phosphine oxide, characterized by the following synthesis steps:

[0023] Step 1: Mix o-bromine iodobenzene or 1,2-diiodobenzene with aromatic ring or aromatic heterocyclic compound containing boric acid or boric acid ester in a molar ratio of 1:0.9-1:2, and obtain intermediate product a by Suzuki reaction;

[0024] Step 2: Mix intermediate product a with n-butyl lithium, and after 1 hour of lithium-halogen exchange reaction, add chloro-diphenyl phosphine to obtain intermediate product b;

[0025] Step 3: Oxidize intermediate product b with 30% H2O2 to obtain the target product, i.e. the twisted structure triphenyl phosphine oxide derivative.

[0026] An organic luminescent co-crystal material with the twisted structure triphenyl phosphine oxide derivative as the donor Y, characterized in that: the organic luminescent co-crystal material comprises an acceptor X and a donor Y, which are mixed in a molar ratio of 1:0.5-1:3, and orderly arranged and co-assembled to form a co-crystal by using non-covalent bond interaction force; wherein: the acceptor X is a strong electron-withdrawing planar small molecule, and the donor Y is a twisted structure triphenyl phosphine oxide derivative.

[0027] The acceptor X is selected from any one of the following molecules:

[0028]

[0029] A preparation method of the organic luminescent co-crystal material, characterized in that: the acceptor and donor molecules are mixed in a molar ratio of 1:0.5-1:3, then a good solvent is added, after dissolution, a poor solvent is added, and the host and guest are uniformly and orderly arranged by standing and volatilizing, and after the solvent is completely volatilized, the organic luminescent co-crystal is obtained.

[0030] When standing and volatilizing, the heating is used to control the volatilization speed of the solvent, and the heating temperature is 25-55°C.

[0031] The volume ratio of the good solvent and the poor solvent ranges from 1:1 to 1:3.

[0032] The good solvent includes dichloromethane, acetone, chloroform, tetrahydrofuran or ethyl acetate.

[0033] The poor solvent includes ethanol, n-hexane or methanol.

[0034] A method for using the organic luminescent co-crystal material, characterized by being applied to the fields including but not limited to organic electroluminescent devices, biological imaging and time resolution imaging.

[0035] Advantages

[0036] The application provides a design, preparation and application of an efficient organic luminescent co-crystal, a host-guest doped luminescent material taking iodine-substituted carbazole derivatives as the main body and application of the luminescent material in scintillation crystals, adoption of strong electron-accepting molecules as electron acceptors, adoption of twisted structure triphenyl phosphine oxide derivatives as electron donors, and preparation of the organic luminescent co-crystal through a solution evaporation method. The donor and acceptor molecules are combined and assembled into the organic luminescent co-crystal with a more rigid structure and a more compact arrangement through non-covalent bond interaction. The non-covalent bond interaction in the co-crystal, especially the intermolecular charge transfer, can narrow the energy gap between singlet and triplet states, improve the intersystem crossing rate, and improve the utilization rate of triplet excitons, so that efficient luminescence is realized. The application provides a new design strategy for the design and preparation of a new type of organic luminescent material, and is suitable for an organic light-emitting diode (OLED).

[0037] The application prepares the organic luminescent co-crystal material through the design strategy of "twisted structure + intermolecular weak interaction combination site", and the preparation method is simple. The donor is selected from the twisted structure triphenyl phosphine oxide derivative. Such molecules have large steric hindrance, are beneficial to the stable triplet state, have intermolecular weak interaction combination sites, are easy to form intermolecular weak interaction force in combination with the acceptor molecules, and are beneficial to the formation of the co-crystal. In addition, the luminescent color of the co-crystal can be adjusted through adjustment of the intermolecular interaction force, and high-efficiency luminescent efficiency can be obtained. The application has important significance for the expansion and research of the types of the organic luminescent co-crystal material. The organic luminescent co-crystal material prepared in the application is easy to repeat, has good stability, has different luminescent colors, a long service life and high-efficiency quantum efficiency (78%), and is suitable for the fields of OLEDs, biological imaging and security inks. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 is a steady-state spectrum of the organic luminescent co-crystal material D1 provided by the application.

[0039] Figure 2 is a steady-state spectrum of the organic luminescent co-crystal material D2 provided by the application.

[0040] Figure 3 is a luminescent photo of the materials D1 and D2 under sunlight / ultraviolet light provided by the application.

[0041] Figure 4 The crystal arrangement and intermolecular interaction of the organic light-emitting co-crystal material D1 are provided.

[0042] Figure 5 The crystal arrangement and intermolecular interaction of the organic light-emitting co-crystal material D2 are provided. DETAILED DESCRIPTION

[0043] The present application will be further described in conjunction with the embodiments and drawings:

[0044] To achieve the object of the present application, the present application provides an organic light-emitting co-crystal material, which is composed of an acceptor X and a donor material Y, and the two are orderly arranged by non-covalent bond interaction force to form a co-crystal, as shown in Figure (1):

[0045]

[0046] In the general formula (1), X is an electron acceptor, which can be selected from any one of the following molecules:

[0047]

[0048] The electron donor Y can be a twisted structure triphenyl phosphine oxide derivative, which can be selected from any one of the following molecules:

[0049]

[0050] Each of R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, R19, R20, R21, R22, R23, R24, R25, R26, R27 and R28 is independently selected from any one of hydrogen atom, alkyl, halogen, phenyl, alkoxy, nitro, amino, aldehyde group, cyano.

[0051] The organic co-crystal material shown in example (1) provided by the present application selects a twisted structure triphenyl phosphine oxide derivative as an electron donor and a small molecule with strong electron absorption capacity as an acceptor. The donor and acceptor molecules are orderly assembled into a co-crystal with more rigid structure through non-covalent bond interaction with a fixed molar ratio. The charge transfer in the co-crystal can make the crystal more stable and the structure more compact. In addition, the charge transfer in the co-crystal makes the energy gap between singlet and triplet states narrow, which is conducive to the occurrence of reverse intersystem crossing, thereby realizing a co-crystal with thermal activation delayed fluorescence characteristics. Further, the luminescence properties of the co-crystal can be regulated by changing the molar ratio of the donor and acceptor or selecting different donor and acceptor molecules.

[0052] The preparation method of the organic light-emitting co-crystal

example (1)

[0053] Method: the host molecule and the guest molecule are mixed in a certain molar ratio, a good solvent is added for dissolution, then a poor solvent is added, and the solvent is allowed to evaporate, the evaporation speed of the solvent is controlled, the host and the guest are uniformly and orderly arranged, and after the solvent is completely evaporated, an organic light-emitting co-crystal is obtained.

[0054] Preferably, the good solvent in the preparation method comprises dichloromethane, acetone, chloroform, tetrahydrofuran, ethyl acetate.

[0055] Preferably, the poor solvent in the preparation method comprises ethanol, n-hexane, methanol.

[0056] Preferably, the heating temperature in the preparation method when the solvent is allowed to evaporate is 25-55℃, for example, 30℃, 34℃, 38℃, 40℃, 42℃, 44℃, 46℃, 48℃, 50℃, 52℃, 54℃, 55℃, etc.

[0057] The application will be further described below through specific examples, but the application is not limited to this specific example.

[0058] Preparation of triphenylphosphine oxide derivative with structural distortion:

[0059] Example 1:

[0060]

[0061] Synthesis of intermediate

oIDBzTP

[0062] Dibenzothiophene-4-boronic acid ester (3.00 g, 9.67 mmol) was dissolved in 40 mL of tetrahydrofuran solution under nitrogen atmosphere, then 1,2-diiodobenzene (3.51 g, 10.64 mmol) and potassium carbonate (4.01 g, 29.01 mmol) and 5 mL of distilled water were added. Then Pd(PPh3)4 (0.10 g, 0.09 mmol) was added, the reaction was warmed to 85℃, and the reaction was carried out for 16 h. After the reaction was completed, the temperature was lowered to room temperature, and the reaction was extracted with water and dichloromethane three times, the organic layer was collected and dried with anhydrous Na2SO4, filtered, and the filtrate was rotary evaporated under reduced pressure to obtain a crude product. Finally, column chromatography separation and purification were carried out with dichloromethane and n-hexane (1 / 3, v / v) to obtain white solid product 1.49 g, with a yield of 40%.

[0063] (1) Synthesis of intermediate

TP-o-DBzTP

[0064] The oIDBzTP (1.50 g, 3.88 mmol) was dissolved in 50 mL of dry tetrahydrofuran under nitrogen atmosphere and, when the temperature of the system had dropped to -78°C, n-butyllithium (1.86 mL, 4.66 mmol, 2.50 M) was added slowly. The reaction was stirred for 1 h at -78°C. Then chlorodiphenylphosphine (1.03 g, 4.66 mmol) was added slowly to the reaction and the reaction was continued for 2 h. Subsequently, the reaction was allowed to warm to room temperature overnight. After the reaction was completed, the reaction was quenched with 100 mL of water and extracted with dichloromethane and water three times. The organic layer was collected and dried over anhydrous Na2SO4, filtered and the filtrate was evaporated under reduced pressure to obtain the crude product. Finally, the product was purified by column chromatography using dichloromethane and n-hexane (1 / 3, v / v) as eluents to obtain the product as a white solid 0.60 g with a yield of 35%.

[0065] (3) Synthesis of the target product TPO-o-DBzTP

[0066] The TP-o-DBzTP (0.50 g, 1.47 mmol) was dissolved in 20 mL of tetrahydrofuran and 2 mL of 30% H2O2 was added. The reaction was stirred for 30 min. After the reaction was completed, the reaction was extracted with water and dichloromethane three times. The organic layer was collected and dried over anhydrous Na2SO4, filtered and the filtrate was evaporated under reduced pressure to obtain the crude product. Finally, the product was purified by column chromatography using ethyl acetate / n-hexane (1 / 1, v / v) as eluents to obtain the product as a white solid 0.48 g with a yield of 93%.

[0067] Example 2:

[0068]

[0069] Synthesis of the intermediate

oIDBzFR

[0070] The dibenzo furan-4-boronic acid ester (3.00 g, 10.20 mmol) was dissolved in 40 mL of tetrahydrofuran under nitrogen atmosphere and o-bromoiodobenzene (3.17 g, 11.22 mmol) and potassium carbonate (4.23 g, 30.60 mmol) and 5 mL of distilled water were added. Subsequently, Pd(PPh3)4(0.10 g, 0.09 mmol) was added and the reaction was allowed to warm to 85°C and the reaction was continued for 16 h. After the reaction was completed, the temperature was allowed to drop to room temperature and the reaction was extracted with water and dichloromethane three times. The organic layer was collected and dried over anhydrous Na2SO4, filtered and the filtrate was evaporated under reduced pressure to obtain the crude product. Finally, the product was purified by column chromatography using dichloromethane and n-hexane (1 / 3, v / v) as eluents to obtain the product as a white solid 2.20 g with a yield of 67%.

[0071] (2) Synthesis of the intermediate

TP-o-DBzFR

[0072] oIDBzFR (2.00 g, 6.19 mmol) was dissolved in 50 mL of dry tetrahydrofuran under nitrogen atmosphere. When the temperature of the system dropped to -78 °C, n-butyllithium (4.60 mL, 7.43 mmol, 1.60 M) was slowly added. The reaction was stirred for 1 h at -78 °C. Then chlorodiphenylphosphine (1.03 g, 4.66 mmol) was slowly added to the reaction. The reaction was continued for 2 h. After 2 h, the reaction was allowed to warm to room temperature overnight. After the reaction was completed, the reaction was quenched with 100 mL of water. The reaction was extracted with dichloromethane and water three times. The organic layer was collected and dried over anhydrous Na2S04. The filtrate was concentrated under reduced pressure to obtain the crude product. Finally, the product was purified by column chromatography using dichloromethane and n-hexane (1 / 3, v / v) as the eluent to obtain the white solid product 1.85 g with a yield of 70%.

[0073] (3) Synthesis of the target product TPO-o-DBzFR

[0074] TP-o-DBzFR (1.85 g, 1.47 mmol) was dissolved in 30 mL of tetrahydrofuran. Then 5 mL of 30% H2O2 was added. The reaction was stirred for 30 min. After the reaction was completed, the reaction was extracted with water and dichloromethane three times. The organic layer was collected and dried over anhydrous Na2S04. The filtrate was concentrated under reduced pressure to obtain the crude product. Finally, the product was purified by column chromatography using ethyl acetate / n-hexane (1 / 1, v / v) as the eluent to obtain the white solid product 1.80 g with a yield of 94%.

[0075] Preparation of organic luminescent co-crystals using structurally twisted triphenylphosphine oxide derivatives:

[0076] Example 4:

[0077] Preparation of the organic room-temperature phosphorescent material D1 : TPO-o-DBzTP (46.0 mg, 99.9 μmol) and 1,2,4,5-tetracyanobenzene (35.6 mg, 199.8 μmol) were weighed into a sample bottle, dissolved in 3-5 mL of dichloromethane, and then slowly added with ethanol (volume ratio of dichloromethane to ethanol = 1 / 3). After the solvents were completely volatilized, yellow crystals of D1 were obtained.

[0078]

[0079] Example 5:

[0080] Preparation of organic room temperature phosphorescent material D2: TPO-o-DBzFR (44.0 mg, 99.0 μmol) and 1,2,4,5-tetracyanobenzene (35.3 mg, 198.0 μmol) were weighed into a sample bottle, dissolved in 3-5 ml dichloromethane, and then slowly added with ethanol (volume ratio of dichloromethane to ethanol: 1 / 3). After standing and volatilizing the solvent, yellow crystals of D2 were obtained.

[0081]

[0082] Table 1 Steady-state emission wavelengths of room temperature phosphorescent materials D1 and D2 in the above examples

[0083]

[0084] Figure 1 and Figure 2 are the emission spectra of D1 and D2, respectively, with emission peaks at 531 nm and 494 nm, respectively. Figure 3 are the photographs of the luminescence of D1 and D2 under sunlight / ultraviolet excitation. D1 and D2 are yellow crystals under sunlight, and yellow light and blue-green light, respectively, under ultraviolet excitation. Figure 4 and Figure 5 show the crystal arrangement and intermolecular interaction of D1 and D2. There are a large number of intermolecular interaction forces in the luminescent co-crystal material, such as N···S, C-H···O, C-H···N, π···π in D1, and C-H···O, C-H···N, π···π in D2.

[0085] In summary, the organic luminescent co-crystal prepared in the present application has a high luminescence quantum yield of up to 78%. The twisted donor can provide more intermolecular weak interaction binding sites, and can well recognize and assemble with the acceptor molecules, thus simplifying the screening process of the donor and acceptor molecules. Further, the luminescent properties of the co-crystal can be regulated by adjusting the ratio of the donor and acceptor molecules or selecting different donor / acceptor molecules. The preparation process of the present application is simple, easy to repeat, and stable. The organic luminescent co-crystal material prepared has different luminescent colors, lifetimes, and luminous brightness, and is suitable for use in the fields of OLED, biological imaging, and security ink. The above, those of ordinary skill in the art can make other various corresponding changes and modifications according to the technical solutions and technical concepts of the present application, and all these changes and modifications shall belong to the protection scope of the claims of the present application.

Claims

1. An organic co-crystal material of a structurally distorted triphenyl phosphine oxide derivative as a donor Y, characterized in that, The organic light-emitting co-crystal material comprises an acceptor X and a donor Y, which are arranged and co-assembled into a co-crystal by non-covalent bond interaction force by being mixed in a molar ratio of 1:0.5-1:3; wherein: the acceptor X is a strong electron-withdrawing planar small molecule, and the donor Y is a structurally twisted triphenyl phosphine oxide derivative; The structurally twisted triphenyl phosphine oxide derivative is: or ; The strong electron-withdrawing planar small molecule is: .

2. A method of preparing the organic co-crystal material of claim 1, characterized by: The acceptor X and the donor Y are mixed in a molar ratio of 1:0.5-1:3, then a good solvent is added, after dissolution, a poor solvent is added, and the host and the guest are uniformly and orderly arranged by standing and volatilization; after the solvent is completely volatilized, the organic light-emitting co-crystal is obtained.

3. The method of claim 2, wherein: During the standing and volatilization, the volatilization speed of the solvent is controlled by heating, and the heating temperature is 25-55 DEG C.

4. The method of claim 2, wherein: The volume ratio of the good solvent to the poor solvent is 1:1-1:

3.

5. The method of claim 4, wherein: The good solvent is dichloromethane, acetone, chloroform, tetrahydrofuran or ethyl acetate.

6. The method of claim 4, wherein: The poor solvent is ethanol, n-hexane or methanol.

7. A method of using the organic co-crystal material of claim 1, characterized by: It is applied to the field of organic electroluminescent devices or time-resolved imaging.

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