Ionic liquid room temperature phosphorescent material and preparation method thereof

Abstract

The invention discloses an ionic liquid room-temperature phosphorescent material and a preparation method thereof, the structural formula of the ionic liquid room-temperature phosphorescent material is # imgabs0 #, n is 2-6, R1 is a phosphorescent group, and R2 and R3 are both ionic groups. The ionic liquid room-temperature phosphorescent material has the characteristic of flexibility of an organic material, so that the ionic liquid room-temperature phosphorescent material can bear mechanical deformation such as bending, stretching and the like, keeps stable phosphorescent emission performance, and can better adapt to various complex shapes and environments in practical application. Besides, the raw materials used by the ionic liquid room-temperature phosphorescent material are low in price and easy to obtain, and the ionic liquid room-temperature phosphorescent material is few in synthesis steps and low in biotoxicity and has huge application potential in the fields of information encryption, biological imaging, flexible photoelectric devices and the like.

Description

Technical Field

[0001] The present application relates to the technical field of new materials, and mainly to an ionic liquid room temperature phosphorescent material and a preparation method thereof. Background Art

[0002] Organic room temperature phosphorescent (RTP) materials have become a hot topic in optical and material research in recent years due to their unique excited state properties, such as large Stokes shift, high quantum efficiency and long lifetime. RTP materials can achieve long-term phosphorescent emission at room temperature, overcoming the limitation that traditional fluorescent materials cannot maintain excited states at high temperature or room temperature. Therefore, they have broad application potential in display technology, sensors, optical storage and bioimaging. However, existing RTP materials are mostly organic crystals or polymers, which have the disadvantages of poor processing performance and flexibility, which makes them difficult to be popularized in practical applications, especially in flexible electronic devices and wearable technologies. Therefore, the development of RTP materials with better processability, flexibility and stretchability remains one of the key challenges of current research.

[0003] Ionic liquids (ILs) refer to liquids composed entirely of ions that exhibit high viscosity and high ductility at room temperature. ILs are considered to be very promising candidates in the field of phosphorescent material research due to their excellent physicochemical properties, such as high thermal and chemical stability, excellent conductivity, and adjustable ionic structure. However, there are currently very few reports on the phosphorescence emission of single-component ILs. Most research efforts focus on the composite systems of ILs, or on enhancing their phosphorescent properties by doping luminescent molecules into ILs. In fact, it is rare for pure single-component ILs to emit phosphorescence themselves. This is mainly because the strong mobility of ILs often leads to non-radiative transitions of excitons, thereby suppressing the emission of phosphorescence.

[0004] Therefore, it is of great significance to research and develop a new material that can not only overcome the shortcomings of traditional RTP materials in terms of poor processing performance and flexibility, but also possess the excellent physical and chemical properties of ionic liquids. Summary of the invention

[0005] In view of the technical problems existing in the prior art, the present application proposes an ionic liquid room temperature phosphorescent material and a preparation method thereof.

[0006] According to one aspect of the present invention, an ionic liquid room temperature phosphorescent material is proposed, and its structure is shown in the following formula:

[0007] Wherein, n is 2-6, R1 is a phosphorescent group, and R2 and R3 are both ionic groups.

[0008] The ionic liquid room temperature phosphorescent material of the present invention can exhibit significant room temperature phosphorescent properties through ultraviolet light excitation. The material not only maintains the excellent high thermal stability and adjustability of traditional ILs, but also can further enhance the phosphorescent emission ability by optimizing its molecular structure.

[0009] In a specific embodiment, the degree of freedom of the system can be changed by introducing alkyl chains of different lengths, thereby achieving regulation of the physical properties and photophysical properties of the ionic liquid room temperature phosphorescent material.

[0010] Preferably, the R1 comprises , , , , , , , , , , , , , , , , , , , , , , , , , , , or .

[0011] In a specific embodiment, R1, as a phosphorescent group, is a core component of the luminescent properties of the material. Selecting a suitable phosphor containing R1 can significantly enhance the phosphorescence emission intensity and lifespan of the ionic liquid room temperature phosphorescent material. By selecting different phosphors, the emission wavelength of the phosphorescence can also be adjusted to achieve phosphorescence emission of different colors, which is particularly important for the application of the material in display technology and optical sensors. At the same time, suitable phosphors can enable the ionic liquid room temperature phosphorescent material to maintain stable performance under a wider range of temperature and chemical environments. In addition, the selection of R1 provides flexibility for the molecular structure optimization of the ionic liquid room temperature phosphorescent material. By adjusting the chemical structure of R1, the efficiency and stability of the phosphorescent emission can be further enhanced.

[0012] In a specific embodiment, R1 is , or The above three R1s can form stable ionic liquids at room temperature and achieve room temperature phosphorescence emission. However, the remaining R1s may have high melting points, which may cause the melting points of the synthesized ionic derivatives to be higher than room temperature, and may not form very stable ionic liquids at room temperature and may solidify.

[0013] Preferably, the R2 comprises or .

[0014] Preferably, said R3 comprises Br - ,I - , Cl - , , , or .

[0015] In a specific embodiment, R2 can enhance the charge separation ability of the molecule, thereby stabilizing the excited state of the phosphorescent group and improving the phosphorescence efficiency; and R3 can further adjust the luminescent properties of the ionic liquid room temperature phosphorescent material by changing the polarity and charge distribution of the ions. The ionic properties of R2 and R3 help to enhance the thermal stability and chemical stability of the ionic liquid room temperature phosphorescent material, allowing it to maintain its performance under a wider range of environmental conditions. At the same time, under the synergistic effect of R2 and R3, the physical and chemical properties of the ionic liquid room temperature phosphorescent material, such as viscosity, ductility and solubility, can also be adjusted to make it more suitable for different application scenarios.

[0016] In a specific embodiment, R2 is , R3 is Br - or The main force of ionic compounds is the electrostatic force between cations and anions. The smaller the ion radius, the shorter the distance between ions, the stronger the electrostatic force, and the higher the melting point. So the anion is replaced from bromide anion to bistrifluoromethanesulfonyl imide anion [TFSI] with a larger radius. - , which can significantly reduce the melting point of ionic compounds and turn them into ionic liquids.

[0017] According to a second aspect of the present invention, a method for preparing an ionic liquid room temperature phosphorescent material is provided, comprising the following steps: S1, adding the phosphor containing R1, dibromoalkane and sodium hydride into the first solvent N,N-dimethylformamide at a molar ratio of 1:1.5-2:1.5-2 to react to obtain the first step product; S2, adding the first step product and triethylamine or trimethylamine into a second solvent, and reacting them at a molar ratio of 1:3 to obtain a second step product containing R2; S3, adding the product of the second step and lithium bis(trifluoromethanesulfonyl imide) into deionized water, and reacting them in a molar ratio of 1:1.2 to obtain the ionic liquid room temperature phosphorescent material.

[0018] In a specific embodiment, DMF can effectively dissolve the phosphor containing R1, dibromoalkane and sodium hydride and other reactants, ensure the uniformity of the reaction system, thereby improving the reaction efficiency and the purity of the product. At the same time, DMF can remain stable during the reaction, and will not introduce additional impurities or interfere with the reaction process. In addition, the polarity of DMF helps to reduce the reaction activation energy, promote the contact and reaction between the reactants, thereby increasing the reaction rate, shortening the reaction time, and improving production efficiency.

[0019] Preferably, in S1, the reaction condition is stirring at room temperature for 6-12 h. Stirring at room temperature is a relatively mild reaction condition, which can avoid side reactions or decomposition reactions that may be caused by high temperature, and helps to maintain the stability of reactants and products. The stirring time of 6-12 h is sufficient to allow the reactants to fully contact and react, ensuring that the reaction is completely carried out, thereby obtaining a high-purity first step product.

[0020] Preferably, the second solvent includes acetonitrile (ACN). Acetonitrile can effectively dissolve the first step product and reactants such as triethylamine or trimethylamine, and acetonitrile has a high boiling point, so that the reaction can be carried out in a higher environment, thereby increasing the reaction rate.

[0021] Preferably, in S2, the reaction condition is stirring at 80° C. for 12-24 h. This temperature helps to break the chemical bonds between the reactants and promote the reaction, thereby significantly increasing the reaction rate and shortening the reaction time.

[0022] Preferably, in S3, the reaction condition is stirring at room temperature for 12 h.

[0023] Preferably, the ionic liquid room temperature phosphorescent material is applied to measure X-ray radiation.

[0024] In a specific embodiment, by precisely controlling the ratio of the dopant to the ionic liquid, when the X-ray radiation intensity reaches a preset limit value, the ionic liquid room temperature phosphorescent material will emit a clear phosphorescence signal, thereby achieving accurate monitoring and quantitative measurement of the X-ray radiation intensity.

[0025] Compared with the prior art, the beneficial effects of this application are: The raw materials used in the ionic liquid room temperature phosphorescent material of the present application are inexpensive and easy to obtain, and have fewer synthesis steps and low biological toxicity, making them more competitive in large-scale industrial production; The ionic liquid room temperature phosphorescent material of the present application has the flexibility characteristics of organic materials, which enables it to withstand mechanical deformation such as bending and stretching while maintaining stable phosphorescent emission performance. In practical applications, it can better adapt to various complex shapes and environments, such as in the fields of flexible electronic devices, wearable technology and smart sensors, and can achieve better fit and durability; (3) The ionic liquid room temperature phosphorescent material of the present application can form a stable ionic liquid and has extremely high processability, and has great application potential in the fields of information encryption, bio-imaging and flexible optoelectronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are included to provide a further understanding of the embodiments and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate the embodiments and are used together with the description to explain the principles of the present invention. It will be easy to recognize other embodiments and many expected advantages of the embodiments because they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale with each other. The same reference numerals refer to corresponding similar parts.

[0027] Figure 1 A flow chart of preparing an ionic liquid room temperature phosphorescent material according to an embodiment of the present invention is shown; Figure 2 The photoluminescence spectrum of the ionic liquid room temperature phosphorescent material under ultraviolet excitation according to a specific embodiment of the present invention is shown; Figure 3 The ionic liquid room temperature phosphorescent material according to a specific embodiment of the present invention is shown. 1 HNMR spectrum; Figure 4 The ionic liquid room temperature phosphorescent material according to a specific embodiment of the present invention is shown. 19 FNMR spectrum; Figure 5 shows a phosphorescence spectrum of an ionic liquid room temperature phosphorescent material under ambient conditions according to a specific embodiment of the present invention; Figure 6 shows a lifetime decay spectrum of an ionic liquid room temperature phosphorescent material under ambient conditions according to a specific embodiment of the present invention; Figure 7 shows the photoluminescence spectrum of the ionic liquid room temperature phosphorescent material under ultraviolet excitation according to another specific embodiment of the present invention; Figure 8 The ionic liquid room temperature phosphorescent material according to another specific embodiment of the present invention is shown. 1 HNMR spectrum; Fig. 9The ionic liquid room temperature phosphorescent material according to another specific embodiment of the present invention is shown. 19 FNMR spectrum; Fig.10 shows a phosphorescence spectrum of an ionic liquid room temperature phosphorescent material under ambient conditions according to another specific embodiment of the present invention; Fig.11 The figure shows the lifetime decay spectrum of the ionic liquid room temperature phosphorescent material under ambient conditions according to another specific embodiment of the present invention. DETAILED DESCRIPTION

[0028] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant inventions, rather than to limit the inventions. It should also be noted that, for ease of description, only the parts related to the relevant inventions are shown in the accompanying drawings, and the embodiments and features in the embodiments of the present application can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0029] Figure 1 The preparation flow chart of the ionic liquid room temperature phosphorescent material according to the present invention is shown as follows: Figure 1 As shown, the specific steps are as follows: S1, adding the phosphor containing R1, dibromoalkane and sodium hydride into the first solvent N,N-dimethylformamide at a molar ratio of 1:1.5-2:1.5-2 to react to obtain the first step product; S2, adding the first step product and triethylamine or trimethylamine into a second solvent, and reacting them at a molar ratio of 1:3 to obtain a second step product containing R2; S3. Put the product of the second step and lithium bis(trifluoromethanesulfonyl imide) into deionized water together, and react them in a molar ratio of 1:1.2 to obtain an ionic liquid room temperature phosphorescent material. Example 1

[0030] An ionic liquid room temperature phosphorescent material, the specific preparation steps of which are as follows: S11. Weigh 10H-phenoselenazine (1.1 g, 4.47 mmol) and sodium hydride (0.36 g, 8.94 mmol) with an electronic balance and add them together to a double-necked round-bottom flask. Add 20 ml of DMF as a solvent to the double-necked round-bottom flask, stir at room temperature, and then add 1,3-dibromopropane (0.90 ml, 8.94 mmol) to it, and continue to stir at room temperature for 6 h. After the reaction is completed, quench the reaction with a large amount of saturated salt water and dissolve it with DMF. Then add ethyl acetate to extract the product three times, take the upper solution, then add anhydrous magnesium sulfate to remove water, and then remove the solvent by vacuum rotary evaporator and make sand. The crude product is purified by column chromatography (petroleum ether: dichloromethane = 10:1) to obtain a colorless and transparent oil.

[0031] S12. Pour the colorless transparent oil obtained in the first step into a new double-necked round-bottom flask, take 25 ml ACN as solvent, stir and dissolve the colorless transparent oil at 80 °C, then add triethylamine (TEA) (1.25 ml, 9 mmol) to it, and react at 80 °C for 12-24 hours. After the reaction is completed, remove the solvent and TEA by vacuum rotary evaporator. Add 30 ml toluene to the crude product, stir at 110 °C for about 30 mins, dissolve the unreacted intermediate and other reactants in hot toluene, pour off the toluene solution while it is hot, repeat this step 2-3 times, and obtain a light yellow solid, that is, an ionic compound with bromide ion as anion.

[0032] S13, dissolve the dried bromide anion compound in 20 ml of deionized water and pour into a new double-necked round-bottom flask, stir at room temperature, weigh lithium bis(trifluoromethanesulfonyl imide) (0.86 g, 3 mmol) and dissolve in 10 ml of deionized water, then drop the lithium bis(trifluoromethanesulfonyl imide) aqueous solution into the bromide anion compound aqueous solution, and react at room temperature for 12 hours. After the reaction is completed, pour out the aqueous solution, add 15 ml of deionized water to the double-necked round-bottom flask and stir to remove excess lithium bis(trifluoromethanesulfonyl imide), repeat this step twice to obtain a crude product. Dissolve the crude product in 30 ml of dichloromethane (DCM), pour it into a separatory funnel, then add 10 ml of deionized water and shake it thoroughly to further remove lithium ions and bromide ions, and repeat this step 3-5 times. After the extraction is completed, the solvent is removed by a vacuum rotary evaporator and placed in a vacuum drying oven at 40°C for 12-24 hours to obtain a light yellow transparent viscous body, namely, an ionic liquid room temperature phosphorescent material.

[0033] Figure 2 is the photoluminescence spectrum of the ionic liquid room temperature phosphorescent material under ultraviolet excitation, according to Figure 2According to the results, the ionic liquid room temperature phosphorescent material has a main emission peak near 550 nm, and the light at 550 nm is green. Figure 2 The illustration in the upper right corner clearly shows that the ionic liquid room temperature phosphorescent material emits green light under ultraviolet excitation. In addition, the delayed emission spectrum and the photoluminescence spectrum are basically consistent, but because the phosphorescence lifetime of the ionic liquid is short and cannot be observed by the naked eye, it can be inferred that its phosphorescence color is also green.

[0034] Figure 3 and Figure 4 The ionic liquid room temperature phosphorescent material 1 HNMR and 19 FNMR spectrum. 1 H NMR (500MHz, DMSO-d6) δ 7.52 – 6.90 (m, 8H), 4.09 (t, J = 6.2 Hz, 2H), 3.25 – 2.90(m, 8H), 1.94 (q, J = 8.0, 5.9 Hz, 2H), 1.00 (t, J = 7.2 Hz, 9H), 19 F NMR (471MHz, DMSO-d6) δ -78.71.

[0035] Figure 5 and Figure 6 The following are the phosphorescence spectrum and lifetime decay spectrum of the ionic liquid room temperature phosphorescent material at room temperature (25 °C), normal pressure, and air atmosphere, where: Figure 5 is the phosphorescence spectrum, Figure 6 is the lifetime decay spectrum. Figure 5 It can be seen that the luminescence intensity of the ionic liquid room temperature phosphorescent material at 550 nm is very strong, and the luminescent color is close to green. Figure 6 The figure shows the decay of the luminescence intensity in the time range from 0 to 5000 microseconds (μs). The red dots in the figure indicate that the luminescence intensity of the ionic liquid room temperature phosphorescent material decays with time. The phosphorescence lifetime of the ionic liquid room temperature phosphorescent material is about 109.38 μs, which has a long phosphorescence lifetime.

[0036] An ionic liquid room temperature phosphorescent material, the specific preparation steps of which are as follows: S21. Weigh 10H-phenoselenazine (1.1 g, 4.47 mmol) and sodium hydride (0.36 g, 8.94 mmol) with an electronic balance and add them together to a double-necked round-bottom flask. Add 20 ml of DMF as a solvent to the double-necked round-bottom flask, stir at room temperature, and then add 1,4-dibromobutane (1.10 ml, 8.94 mmol) to it, and continue to stir at room temperature for 6 h. After the reaction is completed, quench the reaction with a large amount of saturated salt water and dissolve it with DMF. Then add ethyl acetate to extract the product three times, take the upper solution, then add anhydrous magnesium sulfate to remove water, and then remove the solvent by vacuum rotary evaporator and make sand. The crude product is purified by column chromatography (petroleum ether: dichloromethane = 10:1) to obtain a colorless and transparent oil.

[0037] S22. Pour the colorless transparent oil obtained in the first step into a new double-necked round-bottom flask, take 25 ml of ACN as a solvent, stir and dissolve the colorless transparent oil at 80 °C, then add triethylamine (TEA) (1.25 ml, 9 mmol) to it, and react at 80 °C for 12-24 hours. After the reaction is completed, remove the solvent and TEA by a vacuum rotary evaporator. Add 30 ml of toluene to the crude product, stir at 110 °C for about 30 mins, dissolve the unreacted intermediate and other reactants in hot toluene, pour off the toluene solution while it is hot, repeat this step 2-3 times, and obtain a light yellow solid, that is, an ionic compound with bromide ion as anion.

[0038] S23, dissolve the dried bromide anion compound in 20 ml of deionized water and pour into a new double-necked round-bottom flask, stir at room temperature, weigh lithium bis(trifluoromethanesulfonyl imide) (0.86 g, 3 mmol) and dissolve in 10 ml of deionized water, then drop the lithium bis(trifluoromethanesulfonyl imide) aqueous solution into the bromide anion compound aqueous solution, and react at room temperature for 12 hours. After the reaction is completed, pour out the aqueous solution, add 15 ml of deionized water to the double-necked round-bottom flask and stir to remove excess lithium bis(trifluoromethanesulfonyl imide), repeat this step twice to obtain a crude product. Dissolve the crude product in 30 ml of dichloromethane (DCM), pour it into a separatory funnel, then add 10 ml of deionized water and shake it thoroughly to further remove lithium ions and bromide ions, and repeat this step 3-5 times. After the extraction is completed, the solvent is removed by a vacuum rotary evaporator and placed in a vacuum drying oven at 40°C for 12-24 hours to obtain a light yellow transparent viscous body, namely, an ionic liquid room temperature phosphorescent material.

[0039] Figure 7 is the photoluminescence spectrum of the ionic liquid room temperature phosphorescent material under ultraviolet excitation, according to Figure 7According to the results, the ionic liquid room temperature phosphorescent material has a main emission peak near 530 nm, and the light at 530 nm is closer to yellow-green. Figure 7 The illustration in the upper right corner clearly shows that the ionic liquid room temperature phosphorescent material emits obvious yellow-green light under ultraviolet excitation. In addition, the delayed emission spectrum and the photoluminescence spectrum are basically consistent, but because the phosphorescence lifetime of the ionic liquid is short and cannot be observed by the naked eye, it can be inferred that its phosphorescence color is also yellow-green.

[0040] Figure 8 and Fig. 9 The ionic liquid room temperature phosphorescent material 1 HNMR and 19 FNMR spectrum. 1 H NMR (500MHz, DMSO-d6) δ 7.39 (d, J = 7.7 Hz, 2H), 7.28 (t, J = 7.7 Hz, 2H), 7.15 (d,J = 8.2 Hz, 2H), 6.99 (t, J = 7.5 Hz, 2H), 4.03 – 3.96 (m, 2H), 3.22 – 2.97 (m, 8H), 1.66 (d, J = 9.9 Hz, 4H), 1.11 – 0.98 (m, 9H), 19 F NMR (471 MHz, DMSO-d6) δ -78.72.

[0041] Fig.10 and Fig.11 The following are the phosphorescence spectrum and lifetime decay spectrum of the ionic liquid room temperature phosphorescent material at room temperature (25 °C), normal pressure, and air atmosphere, where: Fig.10 is the phosphorescence spectrum, Fig.11 is the lifetime decay spectrum. Fig.10 It can be seen that the luminescence intensity of the ionic liquid room temperature phosphorescent material at 530 nm is very strong, and the luminescent color is close to yellow-green. Fig.11 The figure shows the decay of the luminescence intensity in the time range from 0 to 400 microseconds (μs). The red dots in the figure indicate that the luminescence intensity of the ionic liquid room temperature phosphorescent material decays with time. The phosphorescence lifetime of the ionic liquid room temperature phosphorescent material is about 10.85 μs, which has a medium phosphorescence lifetime and can maintain luminescence for a certain period of time at room temperature.

[0042] The above describes the specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0043] In the description of the present application, it should be understood that the terms "upper", "lower", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. The wording 'comprising' does not exclude the presence of elements or steps not listed in the claims. The wording 'one' or 'an' preceding an element does not exclude the presence of a plurality of such elements. The simple fact that certain measures are recorded in mutually different dependent claims does not indicate that a combination of these measures cannot be used for improvement. Any reference symbols in the claims should not be interpreted as limiting the scope.

Claims

1. An ionic liquid room temperature phosphorescent material, characterized in that: The structure of the ionic liquid room temperature phosphorescent material is shown in the following formula: ， Wherein, n is 2-6, R1 is a phosphorescent group, and R2 and R3 are both ionic groups.

2. The ionic liquid room temperature phosphorescent material according to claim 1, characterized in that: The R1 includes , , , , , , , , , , , , , , , , , , , , , , , , , , , or .

3. The ionic liquid room temperature phosphorescent material according to claim 1, characterized in that: The R2 includes or .

4. The ionic liquid room temperature phosphorescent material according to claim 1, characterized in that: The R3 includes Br - ,I - , Cl - , , , or .

5. A method for preparing an ionic liquid room temperature phosphorescent material as claimed in any one of claims 1 to 4, characterized in that: The following steps are involved: S1, adding the phosphor containing R1, dibromoalkane and sodium hydride into the first solvent N,N-dimethylformamide at a molar ratio of 1:1.5-2:1.5-2 to react to obtain the first step product; S2, adding the first step product and triethylamine or trimethylamine into a second solvent, and reacting them at a molar ratio of 1:3 to obtain a second step product containing R2; S3, adding the product of the second step and lithium bis(trifluoromethanesulfonyl imide) into deionized water, and reacting them in a molar ratio of 1:1.2 to obtain the ionic liquid room temperature phosphorescent material.

6. The method for preparing the ionic liquid room temperature phosphorescent material according to claim 5, characterized in that: In S1, the reaction condition is stirring at room temperature for 6-12 h.

7. The method for preparing the ionic liquid room temperature phosphorescent material according to claim 5, characterized in that: The second solvent includes acetonitrile.

8. The method for preparing the ionic liquid room temperature phosphorescent material according to claim 5, characterized in that: In S2, the reaction conditions are stirring at 80° C. for 12-24 h.

9. The method for preparing the ionic liquid room temperature phosphorescent material according to claim 5, characterized in that: In S3, the reaction condition is stirring at room temperature for 12 h.

10. The ionic liquid room temperature phosphorescent material according to any one of claims 1 to 4, characterized in that: The ionic liquid room temperature phosphorescent material is applied to the measurement of X-ray radiation.

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