阅读说明：本技术 一种基于纤维素的室温磷光材料及其制备方法和应用 (Room-temperature phosphorescent material based on cellulose and preparation method and application thereof ) 是由 秦延林 曾茂株 邱学青 霍延平 林绪亮 张文礼 林煜翔 穆英啸 漆毅 郑嘉怡 徐 于 2021-07-07 设计创作，主要内容包括：本发明属于生物质荧光纳米材料领域,公开了一种基于纤维素的室温磷光材料及其制备方法和应用。该方法包括步骤：将纤维素溶于水后调节pH,加入带氨基的芳环衍生物,在搅拌和两种催化剂的作用下反应24h纤维素与其通过酰胺化反应复合；反应结束后,加入过量四氢呋喃将其沉淀出来,所得固体置入真空干燥箱中干燥,除去聚合物内部结晶水,得到产物。该方法高效简单,反应条件温和,首次实现了纤维素以酰胺化反应合成室温磷光材料,且余辉时长达到肉眼可见水平。所制备的材料具有良好的成膜性与可塑性,能制备成薄膜材料与3D磷光体,在信息加密、防伪、光电器件领域中具有广阔的应用前景,为生物质在有机光电领域高值化利用提供新的思路。(The invention belongs to the field of biomass fluorescent nano materials, and discloses a room temperature phosphorescent material based on cellulose, and a preparation method and application thereof. The method comprises the following steps: dissolving cellulose in water, adjusting pH, adding an aromatic ring derivative with amino, reacting for 24h under the action of stirring and two catalysts, and compounding the cellulose with the cellulose through amidation reaction; and after the reaction is finished, adding excessive tetrahydrofuran to precipitate out, putting the obtained solid into a vacuum drying oven for drying, and removing crystal water in the polymer to obtain the product. The method is efficient and simple, the reaction condition is mild, the synthesis of the room-temperature phosphorescent material by the amidation reaction of the cellulose is realized for the first time, and the afterglow duration reaches the level visible to naked eyes. The prepared material has good film forming property and plasticity, can be prepared into a thin film material and a 3D phosphor, has wide application prospect in the fields of information encryption, anti-counterfeiting and photoelectric devices, and provides a new idea for high-valued utilization of biomass in the field of organic photoelectricity.)

1. A cellulose-based room temperature phosphorescent material, characterized in that: the cellulose-based room temperature phosphorescent material has the following structure:

wherein n is a natural number between 500 and 2000; r is one of H and amino-containing aromatic ring derivatives; the aromatic ring derivative containing amino is one of aniline derivative, naphthalene derivative, biphenyl derivative, phenanthrene derivative, anthracene derivative and pyrene derivative.

2. The method for preparing a room temperature phosphorescent material based on cellulose according to claim 1, which is characterized by comprising the following steps: dissolving cellulose in deionized water, adjusting the pH value to 2.5-6.8, adding N- (3-dimethylaminopropyl) -N' -ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) catalyst, then adding an aromatic ring derivative with amino in nitrogen atmosphere, and reacting at 25-40 ℃ for 24-48 h to perform amidation reaction, wherein the ratio of the cellulose to the aromatic ring derivative with amino is (0.1-0.5 g) to (0.65-13 mmol); after the reaction is finished, precipitating out a solid by using excessive tetrahydrofuran, washing with alcohol, and vacuum-drying at 80-120 ℃ for 2-8 h to obtain the room-temperature phosphorescent material based on cellulose.

3. The method of claim 2, wherein the method comprises the following steps: the cellulose is carboxylated modified cellulose.

4. The method of claim 2, wherein the method comprises the following steps: the aromatic ring derivative with amino is more than one of aniline derivative, naphthalene derivative, biphenyl derivative, phenanthrene derivative, anthracene derivative and pyrene derivative.

5. The method of claim 2, wherein the method comprises the following steps: the ratio of the cellulose to the aromatic ring derivative with amino is 0.5g to 2.6 mmol.

6. The method of claim 2, wherein the method comprises the following steps: the amidation reaction time is 24-36 h.

7. The method of claim 2, wherein the method comprises the following steps: the temperature of the amidation reaction is 25-30 ℃.

8. The method of claim 2, wherein the method comprises the following steps: the dosage of the excessive tetrahydrofuran is 65 to 90 percent of the total mass of the reaction system; the number of times of alcohol washing is 1-3.

9. Use of the cellulose-based room temperature phosphorescent material according to claim 1 in the fields of information encryption, anti-counterfeiting and photoelectric devices.

Technical Field

The invention belongs to the field of biomass fluorescent nano materials, and particularly relates to a room temperature phosphorescent material based on cellulose, and a preparation method and application thereof.

Background

In recent years, with the continuous forward development of industrial society, a large amount of non-renewable fossil resources are developed and utilized, and resource crisis, environmental pollution and energy problems caused by the non-renewable fossil resources severely restrict the sustainable development of human society. The method has the advantages that natural renewable green biomass resources are efficiently developed, and the method is a research hotspot when being applied to new energy materials with excellent performance, low cost, green and high efficiency. The biomass resources are mainly derived from agricultural and forestry wastes and municipal wastes, the annual output of the biomass resources reaches 1700 hundred million tons, the annual combustion amount of fossil energy is only about 250 hundred million tons, and the monograph consumption value is only 1/7 of biomass energy. If the large amount of wood fiber resources can be efficiently utilized, great propulsion effect is brought to energy economy, and the development of novel energy economy is promoted.

The organic room temperature phosphorescent material can generate lasting phosphorescence at room temperature, and has wide application prospects in various fields, such as chemical sensing, biological imaging, anti-counterfeiting encryption and the like. The traditional organic room temperature phosphorescent materials such as organic metal phosphorescent materials generally have the phenomenon of ultra-long room temperature phosphorescence in the modes of crystallization solidification, host-guest interaction and the like, but the methods generally have the problems of poor film forming property, high cost, harsh manufacturing and using conditions and the like of the materials, so that the application of the materials is greatly limited. In recent years, organic room temperature phosphorescent polymers are becoming a popular research, and due to the characteristics of film forming capability and adjustable transparency, the polymers have great potential in the field of design and manufacture of optical devices.

However, since the organic room temperature phosphorescent polymer generally uses polyacrylamide or the like as a polymer skeleton, the cost is high and the biocompatibility is poor, and therefore, it is necessary to find a polymer skeleton with low cost and good biocompatibility. The biomass is used as a natural high molecular long chain, has low cost, has a large amount of carbonyl units and complex crosslinking space in the interior, and has unique advantages in the field of organic room temperature phosphorescent polymers.

At present, the long-acting phosphorescent material prepared by taking cellulose as a main body is mainly prepared by embedding high-activity phosphors, such as carbon dots, metal ions and the like, into the cellulose, the non-radiative relaxation process is mutually promoted, the phosphorescent service life is between 100ms, but the level of the phosphorescent material can not be seen by naked eyes; and through simple amidation reaction, the phosphorescence service life of the cellulose-based phosphorescent material can reach the level visible to naked eyes, and the cellulose-based phosphorescent material has certain leading property.

Disclosure of Invention

In order to realize the application of biomass in the field of organic photoelectric materials, overcome the problems of poor film-forming property, high cost and the like of the existing organic room-temperature phosphorescent materials, and overcome the pain points of narrow application range, low efficiency and the like of the organic room-temperature phosphorescent materials, the invention mainly aims to provide the room-temperature phosphorescent materials based on cellulose.

The invention also aims to provide a preparation method of the cellulose-based room temperature phosphorescent material. According to the method, a large number of amido bonds are bonded with an organic ligand with an aromatic ring by utilizing a semi-rigid high polymer chain of cellulose, so that the interaction of hydrogen bonds among molecules and the stacking of pi-pi bonds are realized, and finally the material has a long afterglow property; the cellulose used as the biomass has the characteristics of low cost, mild synthesis process operating conditions, high grafting efficiency, strong plasticity and the like, and has great application value and considerable market prospect.

It is a further object of the present invention to provide a use of the above-mentioned cellulose-based room temperature phosphorescent material.

The purpose of the invention is realized by the following technical scheme:

a cellulose-based room temperature phosphorescent material having a structure of:

wherein n is a natural number between 500 and 2000; r is one of H and amino-containing aromatic ring derivatives; the aromatic ring derivative containing amino is one of aniline derivative, naphthalene derivative, biphenyl derivative, phenanthrene derivative, anthracene derivative and pyrene derivative.

The preparation method of the room temperature phosphorescent material based on the cellulose comprises the following operation steps: dissolving cellulose in deionized water, adjusting the pH value to 2.5-6.8, adding N- (3-dimethylaminopropyl) -N' -ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) catalyst, then adding an aromatic ring derivative with amino in nitrogen atmosphere, and reacting at 25-40 ℃ for 24-48 h to perform amidation reaction, wherein the ratio of the cellulose to the aromatic ring derivative with amino is (0.1-0.5 g) to (0.65-13 mmol); after the reaction is finished, precipitating out a solid by using excessive tetrahydrofuran, washing with alcohol, and vacuum-drying at 80-110 ℃ for 2-8 h to obtain the room-temperature phosphorescent material based on cellulose.

The cellulose is carboxylated modified cellulose.

The aromatic ring derivative with amino is more than one of aniline derivative, naphthalene derivative, biphenyl derivative, phenanthrene derivative, anthracene derivative and pyrene derivative.

The ratio of the cellulose to the aromatic ring derivative with amino is 0.5g to 2.6mmol

The amidation reaction time is 24-36 h.

The temperature of the amidation reaction is 25-30 ℃.

The dosage of the excessive tetrahydrofuran is 65 to 90 percent of the total mass of the reaction system; the number of times of alcohol washing is 1-3.

The room temperature phosphorescent material based on the cellulose is applied to the fields of information encryption, anti-counterfeiting and photoelectric devices.

Compared with the prior art, the invention has the following advantages and effects:

(1) the invention creatively utilizes the cellulose to prepare the organic room temperature phosphorescent polymer, has simple experimental process, convenient operation and low cost of the raw material cellulose, is expected to realize industrial production, has stronger phosphorescent effect compared with the traditional organic room temperature phosphorescent crystal, has higher plasticity degree, breaks the limitation of single application range of the organic room temperature phosphorescent crystal, has extremely high application value and wide market prospect.

(2) According to the invention, the color of phosphorescence can be regulated from green to red by regulating the number of aromatic small molecule aromatic rings in the cellulose polymer, so that the application of the cellulose polymer as a phosphorescence photoelectric device unit is greatly increased, and the high-value utilization of biomass is realized.

(3) The preparation method is efficient and simple, the reaction conditions are mild, the synthesis of the room-temperature phosphorescent material by the amidation reaction of the cellulose is realized for the first time, and the afterglow duration reaches the level visible to naked eyes. The prepared material has good film forming property and plasticity, can be prepared into a thin film material and a 3D phosphor, has wide application prospect in the fields of information encryption, anti-counterfeiting and photoelectric devices, and provides a new idea for high-valued utilization of biomass in the field of organic photoelectricity.

Drawings

FIG. 1 is an infrared spectrum of a cellulose-based room temperature phosphorescent material.

Fig. 2 is a normalized photoluminescence spectrum of a cellulose-based room temperature phosphorescent material.

FIG. 3 is a photograph of a cellulose-based room temperature phosphorescent material taken under 365nm ultraviolet irradiation and after the irradiation was stopped.

Detailed Description

The present invention will be described in further detail with reference to examples, but the embodiments of the present invention are not limited thereto.

The raw materials in the examples are all commercially available; reagents, methods and apparatus used in the present invention are conventional in the art unless otherwise indicated.

Example 1

Dissolving 0.5g carboxymethyl cellulose in 100ml deionized water, adjusting pH to 3.25 with 0.1mol/L HCl, pouring into a three-neck round-bottom flask; 0.498g EDC (2.6mmol) and 0.1500g NHS (1.3mmol) were dissolved in 5ml ultrapure water, respectively, and added to a round-bottom flask; subsequently, aniline solution dissolved in 5mL DMF with a mass of 20 μ l (1.3mmol) was slowly injected under nitrogen; after this, the mixture was stirred at 25 ℃ for 24 h; after the reaction is finished, 20mL of reaction stock solution is quickly taken, excessive tetrahydrofuran (65mL) is used as a poor solvent to precipitate a product, and the product is centrifuged to obtain transparent gel; after alcohol washing, the transparent gel is placed in a vacuum drying oven at 110 ℃ for drying for 4 hours to finally obtain dark yellow hard film-shaped solid with white color, and the room temperature phosphorescent material based on cellulose is obtained.

Example 2

Dissolving 0.2g of carboxymethyl cellulose in 100ml of deionized water, adjusting the pH to 2.85 with 0.2mol/L HCl, and pouring the solution into a three-neck round-bottom flask; 0.498g EDC (2.6mmol) and 0.1500g NHS (1.3mmol) were dissolved in 5ml ultrapure water, respectively, and added to a round-bottom flask; then, slowly injecting a 1-naphthylamine solution dissolved in 5mL of DMF under the protection of nitrogen, wherein the mass of the 1-naphthylamine is 0.0190g (1.3 mmol); after this, the mixture was stirred at 25 ℃ for 24 h; after the reaction is finished, quickly taking 100mL of reaction stock solution, taking excessive tetrahydrofuran (400mL) as a poor solvent to precipitate a product, and centrifuging to obtain transparent gel; after alcohol washing, the transparent gel is placed in a vacuum drying oven at 80 ℃ for drying for 8h, and finally, a dark yellow hard film-shaped solid is obtained, namely the room temperature phosphorescent material based on cellulose. The infrared spectrogram and the normalized photoluminescence spectral characterization of the obtained room temperature phosphorescent material based on the cellulose are shown in figures 1 and 2, and the synthesis of amido bonds is proved to have the following structural formula:

example 3

Dissolving 0.4g of carboxymethyl cellulose in 200ml of deionized water, adjusting the pH to 3.85 by using 0.2mol/L HCl, and pouring the solution into a three-neck round-bottom flask; 0.996g EDC (5.2mmol) and 0.3000g NHS (2.6mmol) were dissolved in 10ml ultrapure water, respectively, and added to a round-bottom flask; then, slowly injecting a 1-aminoanthracene solution dissolved in 10mL of DMF under the protection of nitrogen, wherein the mass of the 1-aminoanthracene is 0.0512g (2.6 mmol); after this, the mixture was stirred at 30 ℃ for 36 h; after the reaction is finished, quickly taking 100mL of reaction stock solution, taking excessive tetrahydrofuran (400mL) as a poor solvent to precipitate a product, and centrifuging to obtain transparent gel; after alcohol washing, the transparent gel is placed in a vacuum drying oven at 100 ℃ for drying for 6 hours to finally obtain a solid with white color, and the room-temperature phosphorescent material based on the cellulose is obtained.

Example 4

Dissolving 1g of carboxymethyl cellulose in 500ml of deionized water, adjusting the pH to 4.5 with 1mol/L HCl, and pouring the solution into a three-neck round-bottom flask; 2.49g EDC (13mmol) and 0.7500g NHS (6.5mmol) were dissolved in 25ml ultrapure water, respectively, and added to a round-bottom flask; then, slowly injecting a 1-aminopyrene solution dissolved in 25mL of DMF under the protection of nitrogen, wherein the mass of the 1-aminopyrene is 0.14g (6.5 mmol); after this, the mixture was stirred at 40 ℃ for 24 h; after the reaction is finished, 50mL of reaction stock solution is quickly taken, excessive tetrahydrofuran (200mL) is used as a poor solvent to precipitate a product, and the product is centrifuged to obtain transparent gel; after alcohol washing, the transparent gel is placed in a vacuum drying oven at 90 ℃ for drying for 5 hours to finally obtain dark yellow hard film-shaped solid with white color, and the room temperature phosphorescent material based on cellulose is obtained.

Example 5

Dissolving 0.6g of carboxymethyl cellulose in 100ml of deionized water, adjusting the pH to 5.35 with 0.1mol/L HCl, and pouring the solution into a three-neck round-bottom flask; 0.996g EDC (5.2mmol) and 0.3000g NHS (2.6mmol) were dissolved in 5ml ultrapure water, respectively, and added to a round-bottom flask; subsequently, a solution of 9-aminoanthracene dissolved in 5mL of DMF with a mass of 0.0512g (2.6mmol) was injected slowly under nitrogen. After this, the mixture was stirred at 25 ℃ for 48 h; after the reaction is finished, quickly taking 30mL of reaction stock solution, taking excessive tetrahydrofuran (135mL) as a poor solvent to precipitate a product, and centrifuging to obtain transparent gel; after alcohol washing, the transparent gel is placed in a vacuum drying oven at 120 ℃ for drying for 2 hours, and finally, a dark yellow hard film-shaped solid is obtained, namely the room temperature phosphorescent material based on the cellulose.

The structural changes of the synthesized polymer can be analyzed by FIG. 1. 1650cm^-1The characteristic absorption peak is shown in the characteristic spectra of the amide group in the polymer, and all the spectra obtained in the characterization examples 1, 2 and 4 show that the amino group in the aromatic ring derivative and the carboxyl group on the cellulose successfully undergo amidation reaction. Example 1, example 2, example 3 and example 4 were characterized by normalized photoluminescence spectra, the results are shown in figure 2. It can be seen that the four materials generate phosphorescence with different wavelengths due to the difference in the number of grafted aromatic rings, since the interaction of hydrogen bonds between molecules and the pi-pi bond stacking together affect the non-radiative relaxation process.

As can be seen from FIG. 3, the phosphorescent materials prepared by examples 1, 2, 3 and 4 have phosphorescence for a long time of 0.5s to 2.25 s to the naked eye level, indicating that according to this method, the biomass-based organic room temperature phosphorescent polymer can be simply prepared, and the phosphorescence color can be changed according to the density of the grafted aromatic ring compound, from blue-green represented by aniline to red represented by 1-aminopyrene.

The performance test comparison of the cellulose-based room temperature phosphorescent material of the invention and the traditional phosphorescent material is shown in Table 1:

TABLE 1 comparison of the advantages of cellulose-based room-temperature phosphorescent materials and conventional organic phosphorescent crystals

In table 1, it can be shown that compared with the conventional inorganic phosphorescent crystal material and organic phosphorescent crystal material, the invention has the advantages of simple synthesis process, low toxicity, lower raw material cost, better film forming property, low production cost, and more benefit for the application in the actual field.

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.