An indole derivative doped material with host-guest room temperature phosphorescence interconversion characteristics, a preparation method and encryption applications thereof

Abstract

This invention discloses an indole derivative-doped material with host-guest room-temperature phosphorescence interconversion characteristics, its preparation method, and its encryption applications, belonging to the field of organic light-emitting materials technology. The indole derivative-doped material includes a host material and a guest material, both of which are indole derivatives. By introducing different types of substituent groups into the indole skeleton, the photophysical properties of the material are effectively controlled, thereby obtaining a series of functionalized host and guest materials. Further, by physically doping the aforementioned host and guest materials, an organic room-temperature phosphorescent material with visible long afterglow characteristics and interconvertible host and guest room-temperature phosphorescence is obtained. This organic room-temperature phosphorescent material can be used in information display, time-resolved anti-counterfeiting technology, Morse code encryption, and information encryption storage microarrays based on ASCII binary encoding, among other fields.

Description

Technical Field

[0001] This invention belongs to the field of organic light-emitting materials technology, specifically relating to an indole derivative doped material with host-guest room temperature phosphorescence interconversion characteristics, its preparation method, and its encryption applications. Background Technology

[0002] Organic room-temperature phosphorescent materials are a special optical phenomenon in which light continues to emit light for seconds or even hours after the external excitation source is turned off. Due to their long triplet lifetime and ability to effectively avoid interference from biological background fluorescence, organic room-temperature phosphorescent materials have attracted widespread attention in fields such as bioimaging, optoelectronic devices, anti-counterfeiting, information storage, and displays. Compared to inorganic phosphorescent materials, organic room-temperature phosphorescent materials possess advantages such as low toxicity, low cost, good processability, easily modifiable unique structures, and good biocompatibility, making them a current research hotspot in novel luminescent materials.

[0003] However, the weak spin-orbit coupling and rapid nonradiative transitions in purely organic materials suppress the generation and utilization of triplet excitons, greatly limiting the development and application of organic room-temperature phosphorescent materials. Currently, to achieve efficient organic room-temperature phosphorescence, two approaches are being taken: first, introducing heteroatoms and / or heavy atoms to enhance spin-orbit coupling and promote intersystem crossing between excited singlet and triplet states; second, providing a rigid environment or energy transfer through crystal engineering and host-guest doping strategies to achieve phosphorescence emission. Among these, host-guest doping strategies offer advantages such as simple and effective preparation, low cost, rich molecular structures, and universality, making them highly promising for the development of organic room-temperature phosphorescent materials.

[0004] Nevertheless, research on host-guest doped systems in the field of organic room-temperature phosphorescence still faces significant challenges. This is mainly because most reported host-guest doped systems generally exhibit single-host phosphorescence, while host phosphorescence has been neglected for many years. Consequently, for the same guest dopant, the phosphorescence emission color of the doped system hardly changes, and the potential performance of host-guest doped systems has not been fully explored.

[0005] Therefore, developing a novel doping system capable of dynamic interconversion of host and guest phosphorescence is urgently needed to overcome the bottlenecks of single phosphorescence color and limited control dimensions in existing technologies and to promote the practical application of organic room temperature phosphorescent materials. Summary of the Invention

[0006] To address the aforementioned deficiencies in existing technologies, this invention provides an indole derivative-doped material with host-guest room-temperature phosphorescence interconversion characteristics, its preparation method, and its encryption applications. The indole derivative-doped material comprises a host material and a guest material, both of which are indole derivatives. By introducing different types of substituent groups into the indole skeleton, the photophysical properties of the material are effectively controlled, thereby obtaining a series of functionalized host and guest materials. Further, by physically doping the aforementioned host and guest materials, an organic room-temperature phosphorescent material with visible long afterglow characteristics and interconvertible host and guest room-temperature phosphorescence is obtained. This organic room-temperature phosphorescent material can be used in fields such as information display, time-resolved anti-counterfeiting technology, Morse code encryption, and information encryption storage microarrays based on ASCII binary encoding.

[0007] This invention is achieved through the following technical solution:

[0008] In a first aspect, the present invention provides an indole derivative-doped material with host-guest room temperature phosphorescence interconversion characteristics, comprising a host material and a guest material; the host material is an indole derivative represented by general formula I, wherein, in general formula I, R1 is selected from one of carbon, nitrogen, oxygen, phosphorus, sulfur, selenium, aromatic amines, heteroaromatic amines, and sulfone groups; R2 is selected from C3-C5 straight-chain alkyl groups, C7-C6 straight-chain alkyl groups, and C7-C6 straight-chain alkyl groups. 10 One or more of the following: cycloalkyl, cyano, halogen, amino, and hydroxyl;

[0009]

[0010] The guest material is an indole derivative represented by general formula II, wherein in general formula II, R3 is selected from one of carbon, nitrogen, oxygen, phosphorus, sulfur, selenium, aromatic amine, heteroaromatic amine, and sulfone; and R4 is selected from one of aromatic hydrocarbons or heterocyclic aromatic hydrocarbons.

[0011]

[0012] The doping ratio of the guest material is 0.0001 wt% to 50 wt% of the mass of the host material.

[0013] Furthermore, the doping ratio of the guest material is 0.005wt%-10wt%.

[0014] Furthermore, the host material is indole(2,3-b)cycloheptene, and the guest material is 1H-benzo[f]indole.

[0015] Secondly, the present invention also provides a method for preparing an indole derivative-doped material with host-guest room temperature phosphorescence interconversion characteristics, specifically comprising the following steps:

[0016] Step 1: Dissolve the host material and guest material separately in a good solvent, and sonicate to prepare a solution of host material and guest material of a certain concentration;

[0017] Step 2: Mix the main solution and the guest solution at a certain mass ratio, add a poor solvent, and obtain a mixed solution;

[0018] Step 3: Under vacuum, heat and evaporate the above mixed solution to obtain indole derivative doped material.

[0019] Further, in step one, the good solvent is dichloromethane, tetrahydrofuran, acetone, toluene, methanol, ethanol, or acetonitrile, the ultrasonic time is 10 min to 60 min, the concentration of the main material is 20 mg / mL to 100 mg / mL, and the concentration of the guest material is 0.5 mg / mL to 10 mg / mL.

[0020] Further, in step one, the good solvent is dichloromethane, the ultrasonic time is 30 min, the concentration of the host material is 30 mg / mL, and the concentration of the guest material is 1 mg / mL.

[0021] Furthermore, in step two, the proportion of the guest material is 0.0001 wt% to 50 wt% of the host material, and the undesirable solvent is n-hexane, petroleum ether, or water, with a volume ratio of undesirable solvent to good solvent of 1-20:1.

[0022] Furthermore, in step two, the proportion of the guest material is 0.005wt%-10wt% of the host material, the undesirable solvent is n-hexane, and the ratio of the undesirable solvent to the good solvent is (3-5):1.

[0023] Furthermore, in step three, the vacuum degree is 0.1–30 kPa and the heating temperature is 20–50 °C.

[0024] Furthermore, in step three, the vacuum degree is 0.1–5 kPa and the heating temperature is 25–30 °C.

[0025] Thirdly, the present invention also provides an application of indole derivative doped materials with host-guest room temperature phosphorescence interconversion properties in encryption, specifically including:

[0026] The dynamic switching of phosphorescent emission color between orange and green is achieved by adjusting the host-guest doping ratio;

[0027] A time-resolved anti-counterfeiting system was constructed by utilizing the adjustable phosphorescence lifetime in the range of 18.79–472 ms.

[0028] A microarray for encrypted information storage is constructed based on ASCII binary encoding.

[0029] Compared with the prior art, the advantages of the present invention are as follows:

[0030] 1. The organic room temperature phosphorescent material provided by this invention has indole derivatives as both the host and guest materials. By introducing different side chain groups and different doping units and ratios, long-lifetime room temperature phosphorescent emission is successfully achieved, overcoming the problem of low triplet exciton utilization in pure organic materials.

[0031] 2. This invention is the first to realize the interconversion between host room temperature phosphorescence and guest room temperature phosphorescence. By adjusting the host-guest mass ratio, the phosphorescence emission of the doped system can be interconverted between host phosphorescence and guest phosphorescence, breaking through the limitation of existing host-guest systems that only display single guest phosphorescence.

[0032] 3. The organic room temperature phosphorescent material provided by this invention has phosphorescence performance regulation characteristics. The phosphorescence lifetime, emission color and emission intensity of organic room temperature phosphorescent materials prepared with different mass ratios of host and guest materials can be dynamically adjusted. The phosphorescence lifetime is adjustable in a wide range of 18.79 to 472 ms, and the emission color can achieve phosphorescence emission including orange and green.

[0033] 4. The organic room-temperature phosphorescent material provided by this invention has a long afterglow emission visible to the naked eye at room temperature, and can achieve long-life, multi-color phosphorescence. It has good application prospects in information display, time-resolved anti-counterfeiting technology, Morse code encryption, and information encryption storage microarrays based on ASCII binary encoding. Attached Figure Description

[0034] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0035] Figure 1 The room temperature phosphorescence spectra of pure host, pure guest, and P1 provided in Embodiment 1 of the present invention (a), and the room temperature phosphorescence spectra of P1 with different doping mass ratios (b).

[0036] Figure 2 The room temperature phosphorescence lifetime spectrum of P1 provided in Example 1 of the present invention (a), and the phosphorescence images of P1 with different doping mass fractions under 365nm ultraviolet light excitation (b).

[0037] Figure 3 The room temperature phosphorescence spectra of pure host, pure guest, and P2 provided for Comparative Example 1 of the present invention are (a) and (b) normalized room temperature phosphorescence spectra of P2 with different doping mass ratios.

[0038] Figure 4 The room temperature phosphorescence lifetime spectrum of P2 provided for Comparative Example 1 of the present invention is shown in (a), and the phosphorescence images of P2 with different doping mass fractions under 365nm ultraviolet light excitation are shown in (b).

[0039] Figure 5 The room temperature phosphorescence spectra of pure host, pure guest, and P3 provided for Comparative Example 2 of the present invention are (a) and (b) normalized room temperature phosphorescence spectra of P3 with different doping mass ratios.

[0040] Figure 6 The room temperature phosphorescence lifetime spectrum of P3 provided for Comparative Example 2 of the present invention is shown in (a), and the phosphorescence images of P3 with different doping mass fractions under 365nm ultraviolet light excitation are shown in (b).

[0041] Figure 7 The room temperature phosphorescence spectra of pure host, pure guest, and P4 provided for Comparative Example 3 of the present invention are (a) and (b) normalized room temperature phosphorescence spectra of P4 with different doping mass ratios.

[0042] Figure 8 The room temperature phosphorescence lifetime spectrum of P4 provided for Comparative Example 3 of the present invention is shown in (a), and the phosphorescence images of P4 with different doping mass fractions under 365nm ultraviolet light excitation are shown in (b).

[0043] Figure 9 The room temperature phosphorescence spectra of pure host, pure guest, and P5 provided for Comparative Example 4 of the present invention are (a) and (b) normalized room temperature phosphorescence spectra of P5 with different doping mass ratios.

[0044] Figure 10 The room temperature phosphorescence lifetime spectrum of P5 provided for Comparative Example 4 of the present invention is shown in (a), and the phosphorescence images of P5 with different doping mass fractions under 365nm ultraviolet light excitation are shown in (b).

[0045] Figure 11 An application demonstration of organic room-temperature phosphorescent materials in the field of information display, provided as an example of the application of the present invention;

[0046] Figure 12 This invention provides an application example of organic room temperature phosphorescent materials in the field of time-resolved anti-counterfeiting technology.

[0047] Figure 13 An application demonstration of organic room-temperature phosphorescent materials in the field of Morse code encryption, provided as an example of the application of the present invention;

[0048] Figure 14 This invention provides an application example of organic room-temperature phosphorescent materials in the field of information encryption storage microarrays based on ASCII binary encoding. Detailed Implementation

[0049] To clearly and completely describe the technical solution and its specific working process of the present invention, the specific embodiments of the present invention are as follows, in conjunction with the accompanying drawings:

[0050] This invention provides an indole derivative-doped material with host-guest room temperature phosphorescence interconversion characteristics, comprising a host material and a guest material, wherein the doping ratio of the guest material is 0.0001 wt% to 50 wt% of the mass of the host material;

[0051] The main material is an indole derivative represented by general formula I.

[0052]

[0053] In general formula I, R1 is selected from one of carbon, nitrogen, oxygen, sulfur, aromatic amines, heteroaromatic amines, and sulfone groups; the aromatic amine or heteroaromatic amine has any one of the structural formulas III-1-III-6.

[0054]

[0055] Where X is any one of hydrogen, fluorine, chlorine, bromine, and iodine.

[0056] R2 is selected from one or more of hydrogen, methyl, ethyl, propyl, n-butyl, methoxy, ethoxy, cyano, halogen, amino, hydroxyl, and C3-C8 cycloalkyl; the structural formula of the C3-C8 cycloalkyl group is any one of IV-1-IV-6.

[0057]

[0058] The guest material is an indole derivative represented by general formula II.

[0059]

[0060] In general formula II, R3 is selected from carbon, nitrogen, oxygen, sulfur, aromatic amines, heteroaromatic amines, and sulfone groups; the aromatic amine or heteroaromatic amine has any structural formula of III-1-III-6. R4 is selected from hydrogen and the following... Figure V-1 -V-3 is one of the aromatic hydrocarbons or heterocyclic aromatic hydrocarbons shown.

[0061]

[0062] Where X is either hydrogen or nitrogen.

[0063] When general formula I is used as the main material: R1 is selected from nitrogen, and R2 is selected from any one or more of hydrogen, methyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl (i.e., IV-3-IV-6).

[0064] When general formula I is used as the host material, in order to achieve the interconversion of host phosphorescence and guest phosphorescence, R1 is selected from nitrogen and R2 is selected from cycloheptyl.

[0065] When general formula II is used as the guest material: R3 is selected from nitrogen, R4 is selected from formula V-1, and X is hydrogen.

[0066] Example 1

[0067] This embodiment provides an indole derivative-doped material with host-guest room-temperature phosphorescence interconversion properties, comprising a host material and a guest material; the host material in this embodiment is indole (2,3-b)cycloheptene, and the guest material is 1H-benzo[f]indole; both the host and guest materials in this embodiment are commercially available, therefore their preparation steps will not be described in detail. For ease of description, the organic room-temperature phosphorescent material doped in this embodiment is designated as P1.

[0068] This embodiment also provides a method for preparing an indole derivative-doped material with host-guest room temperature phosphorescence interconversion characteristics, specifically including the following steps:

[0069] (1) Place 90 mg of the host material, indole (2,3-b)cycloheptene, in a sample vial, add 3 mL of dichloromethane, and sonicate for 30 min to dissolve completely, preparing a host material solution of 30 mg / mL. Place 16 mg of the guest material, 1H-benzo[f]indole, in a sample vial, add 16 mL of dichloromethane, and sonicate for 30 min to dissolve completely, preparing a guest material solution of 1 mg / mL.

[0070] (2) Mix the host material solution and the guest material solution, wherein the proportions of the guest material are 0.005wt%, 0.1wt%, 0.5wt%, 1wt%, 5wt%, and 10wt% of the host material, respectively. Sonicate for 30 minutes to ensure that the two are fully mixed and homogeneous. Then add n-hexane to the mixed solution, wherein the volume ratio of n-hexane to dichloromethane is 4:1.

[0071] (3) The solvent of the above-mentioned mixed solution of host material and guest material is evaporated at 25°C under vacuum of 1 kPa to obtain an organic room temperature phosphorescent material with uniform doping of host material and guest material.

[0072] The phosphorescence properties of the above-mentioned pure host material, pure guest material, and uniformly doped organic room temperature phosphorescent material were characterized, and the results were as follows: Figure 1 The room-temperature phosphorescence spectra of the pure host, pure guest, and P1, as well as the normalized room-temperature phosphorescence spectra of P1 with different doping mass ratios, are obtained as follows. Figure 2The room-temperature phosphorescence lifetime spectrum of P1 and phosphorescence photographs of P1 with different doping mass fractions under 365nm UV excitation are presented. The data show that pure host and pure guest exhibit no phosphorescence emission at room temperature, but doping results in significant phosphorescence emission, with peaks at 528, 566, and 619 nm. The 528 nm peak corresponds to the host's phosphorescence emission, while the 566 and 619 nm peaks correspond to the guest's. The normalized spectrum clearly shows the interconversion between host and guest room-temperature phosphorescence, depending on the guest material doping ratio. P1 with different doping mass fractions exhibits an orange-to-green phosphorescence transition, corresponding to the interconversion between host and guest room-temperature phosphorescence. Furthermore, the phosphorescence intensity and visible afterglow emission time vary significantly with the guest doping ratio, with a phosphorescence lifetime ranging from 18.79 ms to 108.38 ms. This unique phosphorescence emission behavior is primarily attributed to the small triplet energy level difference (0.33 eV) between the host and guest materials, allowing both triplet-triplet and reverse triplet-triplet energy transfers to coexist in the doped system. Specifically, upon excitation, triplet excitons generated in the host material are transferred to the triplet state of the guest material via triplet-triplet energy transfer. Simultaneously, thanks to the small triplet energy level difference, these excitons can return to the triplet state of the host material via reverse triplet-triplet energy transfer, thus achieving the interconversion of host-room-temperature phosphorescence and guest-room-room-temperature phosphorescence.

[0073] Comparative Example 1

[0074] This comparative example provides an organic room-temperature phosphorescent material doped with an indole derivative as both a host and a guest material. The host material in this comparative example is indole, and the guest material is 1H-benzo[f]indole. Both the host and guest materials in this comparative example are commercially available, therefore their preparation steps will not be described in detail. For ease of description, the organic room-temperature phosphorescent material doped in this comparative example is designated P2.

[0075] This comparative example provides a method for preparing an organic room-temperature phosphorescent material doped with indole derivative host-guest materials, the specific steps of which are as follows:

[0076] (1) Place 90 mg of the host material indole in a sample vial, add 3 mL of dichloromethane, and sonicate for 30 min to dissolve it completely, thus preparing a host material solution of 30 mg / mL. Place 16 mg of the guest material 1H-benzo[f]indole in a sample vial, add 16 mL of dichloromethane, and sonicate for 30 min to dissolve it completely, thus preparing a guest material solution of 1 mg / mL.

[0077] (2) Mix the host material solution and the guest material solution, wherein the guest material is incorporated at proportions of 0.005 wt%, 0.1 wt%, 0.5 wt%, 1 wt%, 5 wt%, and 10 wt% of the host material. Sonicate for 30 minutes to ensure thorough and uniform mixing. Then add n-hexane to the mixed solution, wherein the volume ratio of n-hexane to dichloromethane is 4:1.

[0078] (3) The solvent of the above-mentioned mixed solution of host material and guest material is slowly evaporated at 25°C to 30°C under vacuum of 0.1 kPa to 5 kPa to obtain an organic room temperature phosphorescent material with uniform doping of host material and guest material.

[0079] The phosphorescence properties of the above-mentioned pure host material, pure guest material, and uniformly doped organic room temperature phosphorescent material were characterized, and the results were as follows: Figure 3 The room-temperature phosphorescence spectra of the pure host, pure guest, and P2, as well as the normalized room-temperature phosphorescence spectra of P2 with different doping mass ratios, were obtained. Figure 4 The room-temperature phosphorescence lifetime spectrum of P2 and phosphorescence photographs of P2 with different doping mass fractions under 365nm UV excitation are presented. The data show that pure host and pure guest exhibit no phosphorescence emission at room temperature, but doping results in significant phosphorescence emission, with peaks at 566 and 619 nm. These peaks correspond to the phosphorescence emission of the guest. The normalized spectrum clearly shows that only guest room-temperature phosphorescence emission exists in this comparative example. P2 with different doping mass fractions emits only orange phosphorescence, and the phosphorescence intensity and visible afterglow emission time vary significantly with the guest doping ratio, with a phosphorescence lifetime of 421ms-472ms. This difference in emission behavior is mainly attributed to the large triplet energy level difference (0.68 eV) between the host and guest in this comparative example, resulting in only triplet-triplet energy transfer in the doped system, while reverse triplet-triplet energy transfer does not occur, thus causing the doped system to emit only guest phosphorescence. Specifically, after being excited, the triplet excitons generated by the host material are transferred to the triplet state of the guest material through a triplet-triplet energy transfer process, and then return to the ground state through a subsequent radiative transition process.

[0080] Comparative Example 2

[0081] This comparative example provides an organic room-temperature phosphorescent material doped with an indole derivative as both a host and a guest material. The host material in this comparative example is 2,3-dimethylindole, and the guest material is 1H-benzo[f]indole. Both the host and guest materials in this comparative example are commercially available, therefore their preparation steps will not be described in detail. For ease of description, the organic room-temperature phosphorescent material doped in this comparative example is designated as P3.

[0082] This comparative example provides a method for preparing an organic room-temperature phosphorescent material doped with indole derivative host-guest materials. The specific process is as follows:

[0083] (1) Place 90 mg of the host material 2,3-dimethylindole in a sample vial, add 3 mL of dichloromethane, and sonicate for 30 min to dissolve completely, preparing a host material solution of 30 mg / mL. Place 16 mg of the guest material 1H-benzo[f]indole in a sample vial, add 16 mL of dichloromethane, and sonicate for 30 min to dissolve completely, preparing a guest material solution of 1 mg / mL.

[0084] (2) Mix the host material solution and the guest material solution, wherein the guest material is incorporated at proportions of 0.005 wt%, 0.1 wt%, 0.5 wt%, 1 wt%, 5 wt%, and 10 wt% of the host material. Sonicate for 30 minutes to ensure thorough and uniform mixing. Then add n-hexane to the mixed solution, wherein the volume ratio of n-hexane to dichloromethane is 4:1.

[0085] (3) The solvent of the above-mentioned mixed solution of host material and guest material is slowly evaporated at 25℃-30℃ under vacuum of 0.1kPa-5kPa to obtain organic room temperature phosphorescent material with uniform doping of host material and guest material.

[0086] The phosphorescence properties of the above-mentioned pure host material, pure guest material, and uniformly doped organic room temperature phosphorescent material were characterized, and the results were as follows: Figure 5 The room-temperature phosphorescence spectra of the pure host, pure guest, and P3, as well as the normalized room-temperature phosphorescence spectra of P3 with different doping mass ratios, were obtained. Figure 6The room-temperature phosphorescence lifetime spectrum of P3 and phosphorescence photographs of P3 with different doping mass fractions under 365nm UV excitation are presented. The data show that pure host and pure guest exhibit no phosphorescence emission at room temperature, but doping results in significant phosphorescence emission, with peaks at 566 and 619 nm. These peaks correspond to the phosphorescence emission of the guest. The normalized spectrum clearly shows that only guest room-temperature phosphorescence emission exists in this comparative example. P3 with different doping mass fractions emits only orange phosphorescence, and the phosphorescence intensity and visible afterglow emission time vary significantly with the guest doping ratio, with a phosphorescence lifetime ranging from 247 ms to 372 ms. This difference in emission behavior is mainly attributed to the large triplet energy level difference (0.63 eV) between the host and guest in this comparative example, resulting in only triplet-triplet energy transfer in the doped system, while reverse triplet-triplet energy transfer does not occur, thus causing the doped system to emit only guest phosphorescence. Specifically, after being excited, the triplet excitons generated by the host material are transferred to the triplet state of the guest material through a triplet-triplet energy transfer process, and then return to the ground state through a subsequent radiative transition process.

[0087] Comparative Example 3

[0088] This comparative example provides an organic room-temperature phosphorescent material doped with an indole derivative as both a host and a guest material. The host material in this comparative example is 1,2,3,4-tetrahydrocyclopentano[b]indole, and the guest material is 1H-benzo[f]indole. Both the host and guest materials in this comparative example are commercially available, therefore their preparation steps will not be described in detail. For ease of description, the organic room-temperature phosphorescent material doped in this comparative example is designated as P4.

[0089] This comparative example provides a method for preparing an organic room-temperature phosphorescent material doped with indole derivative host-guest materials. The specific process is as follows:

[0090] (1) Place 90 mg of the host material 1,2,3,4-tetrahydrocyclopentanoid[b]indole in a sample vial, add 3 mL of dichloromethane, and sonicate for 30 min to dissolve completely, preparing a host material solution of 30 mg / mL. Place 16 mg of the guest material 1H-benzo[f]indole in a sample vial, add 16 mL of dichloromethane, and sonicate for 30 min to dissolve completely, preparing a guest material solution of 1 mg / mL.

[0091] (2) Mix the host material solution and the guest material solution, wherein the guest material is incorporated at proportions of 0.005 wt%, 0.1 wt%, 0.5 wt%, 1 wt%, 5 wt%, and 10 wt% of the host material. Sonicate for 30 minutes to ensure thorough and uniform mixing. Then add n-hexane to the mixed solution, wherein the volume ratio of n-hexane to dichloromethane is 4:1.

[0092] (3) The solvent of the above-mentioned mixed solution of host material and guest material is slowly evaporated at 25°C to 30°C under vacuum of 0.1 kPa to 5 kPa to obtain an organic room temperature phosphorescent material with uniform doping of host material and guest material.

[0093] Further characterization of the phosphorescence properties of the above-mentioned pure host material, pure guest material, and uniformly doped organic room temperature phosphorescent material was performed to obtain the following results: Figure 7 The room-temperature phosphorescence spectra of pure host, pure guest, and P4, as well as the normalized room-temperature phosphorescence spectra of P4 with different doping mass ratios, were obtained. Figure 8 The room-temperature phosphorescence lifetime spectrum of P4 and phosphorescence photographs of P4 with different doping mass fractions under 365nm UV excitation are presented. The data show that pure host and pure guest exhibit no phosphorescence emission at room temperature, but significant phosphorescence emission occurs after doping, with peaks at 566 and 619 nm. These peaks correspond to the phosphorescence emission of the guest. The normalized spectrum clearly shows that only guest room-temperature phosphorescence emission exists in this comparative example. P4 with different doping mass fractions emits only orange phosphorescence, and the phosphorescence intensity and visible afterglow emission time vary significantly with the guest doping ratio, with a phosphorescence lifetime ranging from 183ms to 420ms. This difference in emission behavior is mainly attributed to the large triplet energy level difference (0.48 eV) between the host and guest in this comparative example, resulting in only triplet-triplet energy transfer in the doped system, while reverse triplet-triplet energy transfer does not occur, thus causing the doped system to emit only guest phosphorescence. Specifically, after being excited, the triplet excitons generated by the host material are transferred to the triplet state of the guest material through a triplet-triplet energy transfer process, and then return to the ground state through a subsequent radiative transition process.

[0094] Comparative Example 4

[0095] This comparative example provides an organic room-temperature phosphorescent material doped with an indole derivative as both a host and a guest material. The host material in this comparative example is 2,3-endobutylindole, and the guest material is 1H-benzo[f]indole. Both the host and guest materials in this comparative example are commercially available, therefore their preparation steps will not be described in detail. For ease of description, the organic room-temperature phosphorescent material doped in this comparative example is designated as P5.

[0096] This comparative example provides a method for preparing an organic room-temperature phosphorescent material doped with indole derivative host-guest materials. The specific process is as follows:

[0097] (1) Place 90 mg of the host material 2,3-endobutylindole in a sample vial, add 3 mL of dichloromethane, and sonicate for 30 min to dissolve it completely, thus preparing a host material solution of 30 mg / mL. Place 16 mg of the guest material 1H-benzo[f]indole in a sample vial, add 16 mL of dichloromethane, and sonicate for 30 min to dissolve it completely, thus preparing a guest material solution of 1 mg / mL.

[0098] (2) The host material solution and the guest material solution are mixed, wherein the guest material is incorporated at proportions of 0.005 wt%, 0.1 wt%, 0.5 wt%, 1 wt%, 5 wt%, and 10 wt% of the host material. The mixture is sonicated for 30 minutes to ensure thorough and uniform mixing. Subsequently, hexane is added to the mixed solution, wherein the volume ratio of hexane to dichloromethane is 4:1.

[0099] (3) The solvent of the above-mentioned mixed solution of host material and guest material is slowly evaporated at 25℃ to 30℃ under vacuum of 0.1kPa to 5kPa to obtain an organic room temperature phosphorescent material with uniform doping of host material and guest material.

[0100] The phosphorescence properties of the above-mentioned pure host material, pure guest material, and uniformly doped organic room temperature phosphorescent material were characterized, and the results were as follows: Figure 9 The room-temperature phosphorescence spectra of the pure host, pure guest, and P5, as well as the normalized room-temperature phosphorescence spectra of P5 with different doping mass ratios, were obtained. Figure 10The room-temperature phosphorescence lifetime spectrum of P5 and phosphorescence photographs of P5 with different doping mass fractions under 365nm UV excitation are presented. The data show that pure host and pure guest exhibit no phosphorescence emission at room temperature, but doping results in significant phosphorescence emission, with peaks at 566 and 619 nm. These peaks correspond to the phosphorescence emission of the guest. The normalized spectrum clearly shows that only guest room-temperature phosphorescence emission exists in this comparative example. P5 with different doping mass fractions emits only orange phosphorescence, and the phosphorescence intensity and visible afterglow emission time vary significantly with the guest doping ratio, with a phosphorescence lifetime of 396ms-445ms. This difference in emission behavior is mainly attributed to the large triplet energy level difference (0.44 eV) between the host and guest in this comparative example, resulting in only triplet-triplet energy transfer in the doped system, while reverse triplet-triplet energy transfer does not occur, thus causing the doped system to emit only guest phosphorescence. Specifically, after being excited, the triplet excitons generated by the host material are transferred to the triplet state of the guest material through a triplet-triplet energy transfer process, and then return to the ground state through a subsequent radiative transition process.

[0101] Example 2

[0102] like Figure 11 The image shows an application demonstration in the field of information display of an indole derivative-doped organic room-temperature phosphorescent material, where the host and guest room-temperature phosphorescence can be interconverted. Utilizing the long-lifetime phosphorescence characteristic of the organic room-temperature phosphorescent material provided in Example 1 of this invention, the obtained organic room-temperature phosphorescent material was prepared into various letters or patterns using a hollow template-assisted method. After being prepared into patterns such as "H", "N", "U", apples, butterflies, stars, and arrows using a hollow template, the materials exhibited obvious purple, orange, or green luminescence information before and after excitation with 365nm ultraviolet light.

[0103] like Figure 12 The illustration demonstrates the application of the organic room-temperature phosphorescent material provided in this embodiment in the field of time-resolved anti-counterfeiting technology. Utilizing the phosphorescence properties of different organic room-temperature phosphorescent materials at different time resolutions, a spatiotemporally resolved "stars and moon" encryption pattern was designed. Under ultraviolet excitation, a bright purple fluorescent pattern immediately appears. However, after the ultraviolet light source is removed, the color of the pattern immediately changes, with the moon appearing orange and the stars green. Over time, the phosphorescence emission behavior gradually disappears in both space and time, allowing for the observation of a distinguishable spatiotemporal phosphorescent pattern, thus achieving a high level of anti-counterfeiting.

[0104] like Figure 13The image shows a demonstration of the application of the organic room-temperature phosphorescent material provided in this embodiment in the field of Morse code encryption. The organic room-temperature phosphorescent material is assembled into a Morse code for encryption and decryption demonstration. Under room-temperature ultraviolet light irradiation, the entire encrypted signal exhibits purple fluorescence. Due to interference from the background fluorescence signal, no valid information can be obtained. Only when the ultraviolet excitation is turned off will the actual transmitted information be displayed through the afterglow. Subsequently, by decrypting with a Morse code translation, the true messages "LOVE" and "PEACE" are finally obtained.

[0105] like Figure 14 The illustration demonstrates the application of the organic room-temperature phosphorescent material provided in this embodiment in the field of information encryption storage microarrays based on ASCII binary encoding. The organic room-temperature phosphorescent material is assembled into a data storage microarray based on standard 8-bit ASCII character binary codes. A clear phosphorescent emission represents "1", while no clear phosphorescent emission represents "0". Under ultraviolet light irradiation, all information dots display a purple fluorescent signal, which, according to ASCII binary codes, can be converted into invalid information. However, after turning off ultraviolet light irradiation, the original information displayed by the dot matrix can be easily read and converted into "01001000", "01001110", and "01010101", which are decoded according to the binary codes of ASCII characters, corresponding to the uppercase letters "H", "N", and "U".

[0106] In summary, the organic room-temperature phosphorescent material of this invention comprises a host material and a guest material, both of which are indole derivatives. The resulting organic room-temperature phosphorescent material exhibits visible long-afterglow emission and the interconversion of host and guest room-temperature phosphorescence. This organic room-temperature phosphorescent material can be used in fields such as information display, time-resolved anti-counterfeiting technology, Morse code encryption, and information encryption storage microarrays based on ASCII binary encoding.

[0107] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0108] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0109] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. An indole derivative-doped material with host-guest room temperature phosphorescence interconversion properties, characterized in that, Includes both the main material and the object material; The doping ratio of the guest material is 0.0001 wt%-50 wt% of the mass of the host material. The host material is indole(2,3-b)cycloheptene, and the guest material is 1H-benzo[f]indole.

2. The indole derivative-doped material with host-guest room temperature phosphorescence interconversion characteristics as described in claim 1, characterized in that, The doping ratio of the guest material is 0.005 wt%-10 wt%.

3. The method for preparing an indole derivative-doped material with host-guest room temperature phosphorescence interconversion characteristics as described in claim 1, characterized in that, Specifically, the steps include the following: Step 1: Dissolve the host material and guest material separately in a good solvent, and sonicate to prepare a solution of host material and guest material of a certain concentration; Step 2: Mix the main solution and the guest solution at a certain mass ratio, add a poor solvent, and obtain a mixed solution; Step 3: Under vacuum, heat and evaporate the above mixed solution to obtain indole derivative doped material.

4. The method for preparing an indole derivative-doped material with host-guest room temperature phosphorescence interconversion characteristics as described in claim 3, characterized in that, In step one, the good solvent is dichloromethane, tetrahydrofuran, acetone, toluene, methanol, ethanol or acetonitrile, the ultrasonic time is 10 min - 60 min, the concentration of the host material is 20 mg / mL - 100 mg / mL, and the concentration of the guest material is 0.5 mg / mL - 10 mg / mL.

5. The method for preparing an indole derivative-doped material with host-guest room temperature phosphorescence interconversion characteristics as described in claim 3, characterized in that, In step one, the good solvent is dichloromethane, the ultrasonic time is 30 min, the concentration of the host material is 30 mg / mL, and the concentration of the guest material is 1 mg / mL.

6. The method for preparing an indole derivative-doped material with host-guest room temperature phosphorescence interconversion characteristics as described in claim 3, characterized in that, In step two, the proportion of the guest material is 0.0001 wt% - 50 wt% of the host material, and the undesirable solvent is n-hexane, petroleum ether or water, with a volume ratio of undesirable solvent to good solvent of 1-20:

1.

7. The method for preparing an indole derivative-doped material with host-guest room temperature phosphorescence interconversion characteristics as described in claim 3, characterized in that, In step three, the vacuum level is 0.1–30 kPa and the heating temperature is 20–50℃.

8. The method for preparing an indole derivative-doped material with host-guest room temperature phosphorescence interconversion characteristics as described in claim 3, characterized in that, In step two, the proportion of guest material is 0.005 wt% - 10 wt% of host material, the undesirable solvent is n-hexane, and the ratio of undesirable solvent to good solvent is (3-5):1; In step three, the vacuum level is 0.1–5 kPa and the heating temperature is 25–30℃.

9. The application of an indole derivative-doped material with host-guest room-temperature phosphorescence interconversion properties as described in claim 1 in encryption, characterized in that... Specifically, it includes: The dynamic switching of phosphorescent emission color between orange and green is achieved by adjusting the host-guest doping ratio; A time-resolved anti-counterfeiting system was constructed by utilizing the adjustable phosphorescence lifetime in the range of 18.79–472 ms. A microarray for encrypted information storage is constructed based on ASCII binary encoding.

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