阅读说明：本技术 一种偶氮苯基衍生物、太阳热能燃料薄膜复合材料及其制备方法和用途 (Azophenyl derivative, solar thermal energy fuel film composite material, and preparation method and application thereof ) 是由 赵瑞阳 李永仓 韩吉姝 傅云磊 穆家慧 宋修艳 刘福胜 于 2020-12-16 设计创作，主要内容包括：本发明涉及一种偶氮苯衍生物、太阳热能燃料薄膜复合材料及其制备方法和用途,本发明公开了系列偶氮苯衍生物,并提供了通过其制备光致相变型、即用式太阳热能燃料薄膜的方法,制备得到的太阳热能燃料复合薄膜具有较好的机械柔性、光致异构效应和能量存储能力。该复合薄膜在紫外灯辐照下,可以迅速发生顺反异构化而储存能量,随着辐照时间的延长,储存的能量逐渐增大,约2h可达到充满状态,能量密度可达200J/g以上,可以将自身温度持续提升约5℃。充/放能过程具有非常好的可逆性,循环充/放能5次以上无明显衰减。该复合材料具有制备过程简单,环境友好,材料易制得,放热量大,机械柔性好,耐酸碱腐蚀强和循环使用性能好等优点。(The invention relates to an azobenzene derivative, a solar thermal energy fuel film composite material, a preparation method and application thereof, discloses a series of azobenzene derivatives, provides a method for preparing a photoinduced phase change type ready-to-use solar thermal energy fuel film through the azobenzene derivatives, and the prepared solar thermal energy fuel film composite material has good mechanical flexibility, photoinduced isomerism effect and energy storage capacity. The composite film can rapidly generate cis-trans isomerization to store energy under the irradiation of an ultraviolet lamp, the stored energy is gradually increased along with the extension of irradiation time, the full-filling state can be achieved within about 2 hours, the energy density can be more than 200J/g, and the self temperature can be continuously increased by about 5 ℃. The energy charging/discharging process has very good reversibility, and no obvious attenuation exists when the energy charging/discharging is carried out for more than 5 times in a circulating manner. The composite material has the advantages of simple preparation process, environmental friendliness, easiness in preparation, large heat release, good mechanical flexibility, strong acid-base corrosion resistance, good recycling performance and the like.)

1. An azobenzene derivative, characterized in that, at room temperature, the cis-conformation of the azobenzene derivative is liquid, and the trans-conformation is solid, and has a structure shown in formula I:

wherein R is selected from isoamyl, 2-methylbutyl, pent-2-yl, but-3-en-1-yl, but-2-en-1-yl, neopentyl, 1-buten-1-yl or 2-methylprop-1-en-1-yl.

2. A method for preparing the azobenzene derivative according to claim 1, comprising the steps of:

(1) adding p-methylaniline and concentrated hydrochloric acid into a flask, mixing, adding distilled water, and dropwise adding NaNO at 0-5 DEG C₂Continuously stirring the solution to obtain a diazonium salt solution of the p-methylaniline;

(2) mixing phenol and Na₂CO₃And sodium hydroxide, adding water to dissolve, dropwise adding the mixture into the diazonium salt solution of p-methylaniline obtained in the step (1), continuously stirring at room temperature, after the reaction is finished, regulating the pH value to 7 by using hydrochloric acid, filtering a precipitated product, washing with water, drying at room temperature in vacuum, and purifying by using a chromatographic column to obtain p-hydroxymethylazobenzene;

(3) heating p-hydroxy methyl azobenzene and R-Br in a solvent in the presence of sodium hydroxide for reaction, and purifying by a chromatographic column after the reaction is finished to obtain the product.

3. The method for producing an azobenzene derivative according to claim 2, wherein the concentration of concentrated hydrochloric acid in the step (1) is 37%, and the ratio of p-methylaniline to concentrated hydrochloric acid is 1mmol: (0.20-0.50mL), p-methylaniline and NaNO₂The molar ratio of (1) to (1.0-1.5).

4. The method for producing azobenzene derivative according to claim 2, wherein said step (2) comprises reacting phenol with Na₂CO₃And sodium hydroxide is 1 (1.0-1.5) to 0.8-1.3.

5. The method for producing an azobenzene derivative according to claim 2, wherein the column purification in the step (2) is performed by: eluting impurities with petroleum ether and dichloromethane ═ 1 (1-5), eluting the product with dichloromethane, and performing rotary evaporation to obtain the p-hydroxy methyl azobenzene.

6. The method for producing an azobenzene derivative according to claim 2, wherein the molar ratio of p-hydroxymethylazobenzene, R-Br and sodium hydroxide in the step (3) is 1 (1-5) to (1-3).

7. The method for producing an azobenzene derivative according to claim 2, wherein the solvent of the step (3) is absolute ethanol: water is mixed solution of (5-30):1(V/V), heating temperature is 50-90 deg.C, eluent for chromatographic purification is dichloromethane and petroleum ether is 1: (2-5).

8. An azobenzene-based solar thermal fuel film composite, characterized in that it consists of the azobenzene derivative as described in claim 1 and a flexible fabric.

9. The solar thermal fuel film composite of claim 8, prepared by a method comprising: uniformly spreading the solid azo-based solar thermal fuel compound on a flexible fabric, placing the fabric in a dark closed environment, irradiating by using an ultraviolet lamp, and immersing the azo-based solar thermal fuel compound into the fabric when the azo-based solar thermal fuel compound is converted into a liquid state, thus obtaining the flexible composite film.

10. Use of the azo-phenyl solar thermal fuel film composite of claim 8 as a solar thermal storage material.

Technical Field

The invention belongs to the field of clean energy and renewable energy, and mainly relates to design and synthesis of a photoresponse material, a method for preparing a solar thermal energy fuel film composite material by processing and forming, and application of the solar thermal energy fuel film composite material in photo-thermal energy storage and solar energy utilization.

Background

In recent years, the world is facing an energy crisis, the use of fossil fuels in large quantities also causes environmental pollution, and the search for novel renewable clean energy becomes the focus of people. Since the 21 st century, with the continuous development of solar energy resource utilization and the strong demand of people for clean energy, the light-responsive solar thermal energy fuel has become the research focus in the field of clean energy. Solar thermal energy fuel, as a novel energy storage device, provides a closed cycle and renewable energy storage strategy by converting solar energy into chemical energy stored in the form of molecular isomers such as cis/trans azobenzene and the like and releasing the chemical energy in the form of thermal energy under various stimuli. Its energy storage has the advantages of cyclic use, no pollution and zero discharge, so it is widely studied by people.

Solar thermal fuels that have been previously studied are roughly the following: (1) the spin-coating film has the advantages of high cost performance, energy conservation and low pollution, but the spin-coating film has the defect that the large-area preparation cannot be realized; (2) the electrochemical deposition film-forming can accurately control the thickness of the deposition layer and the film-forming speed, the operation is easy, but the film prepared by the method is difficult to peel off, and the practicability is hindered; (3) the carbon nanotube composite material, which is formed by combining photoresponsive molecules and carbon nanotubes, can effectively improve the potential energy density, but requires an organic solvent for auxiliary charging, which undoubtedly pollutes the environment, and the carbon nanotube material is expensive, so the development of the carbon nanotube composite material is limited.

Azobenzene photoresponsive materials are widely researched in recent years due to excellent photo-cis-trans isomerism properties of the azobenzene photoresponsive materials, and are applied to the fields of optical information storage, solar thermal energy fuel, molecular cages, photochromism, nanoimprint, molecular robots and the like. The material is converted from a trans-conformation (stable state) to a cis-conformation (metastable state) under the irradiation of ultraviolet light, has high response speed and high efficiency, can be converted from the cis-conformation to the trans-conformation under the stimulation of heat or visible light, and has very good reversibility in the cis-trans isomerization process. In the process, the trans-conformation of the low-energy state can absorb energy and convert the energy into cis-conformation, and the cis-conformation converts the energy into chemical energy and stores the chemical energy in a chemical bond, so that the energy charging process is completed, and the light energy is converted into the molecular internal energy; under the induction of heat or visible light, the solar energy is reversibly recovered to a trans-conformation to release heat, so that the energy release process is completed, and the aim of converting light energy into heat energy, namely the solar thermal energy fuel, is finally completed.

In the prior art, azobenzene photoresponse materials are mostly reported to be solid in a normal state, for example, azobenzene materials containing graphene structures and corrole have inconvenience in use, and CN111004146A discloses a liquid azobenzene "molecular solar thermal fuel" 4-bromobutoxy-2 ', 6' -diethylazobenzene, which has a melting point of-18.73 ℃, is liquid at normal temperature, can be used as a solvent-free solar thermal energy storage material, and is convenient to use, but when the isomerization rate of a product is 88%, the energy storage capacity is 96.65J/g, the complete energy storage capacity of the product is 42.8KJ/mol, the energy storage capacity is not high, and the energy storage life is short.

In view of the above, it is particularly necessary to provide a solar thermal fuel with high energy charging speed and high energy storage density.

Disclosure of Invention

The invention aims to overcome the defects in the prior art, provides an azobenzene derivative with high energy charging speed and high energy storage density, and also provides a preparation method thereof, a method for preparing a solar thermal energy fuel film composite material by combining with a flexible fabric, and application thereof.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

subject of the technology 1

The invention provides an azobenzene derivative, wherein at normal temperature, cis conformation is liquid, trans conformation is solid, and the azobenzene derivative has a structure shown in a formula I:

wherein R is selected from isoamyl, 2-methylbutyl, pent-2-yl, but-3-en-1-yl, but-2-en-1-yl, neopentyl, 1-buten-1-yl or 2-methylprop-1-en-1-yl.

As some preferred embodiments of the invention, selected from the compounds of the following structures:

1- (4- (isopentyloxy) phenyl) -2- (p-tolyl) diazene

1- (4- (2-methylbutoxy) phenyl) -2- (p-tolyl) diazene

1- (4- (pent-2-yloxy) phenyl) -2- (p-tolyl) diazene

1- (4- (but-3-en-1-yloxy) phenyl) -2- (p-tolyl) diazene

1- (4- ((but-2-en-1-yl) oxy) phenyl) -2- (p-tolyl) diazene

1- (4- (neopentyloxy) phenyl) -2- (p-tolyl) diazene

1- (4- ((1-buten-1-yl) oxy) phenyl) -2- (p-tolyl) diazene

1- (4- ((2-methylprop-1-en-1-yl) oxy) phenyl) -2- (p-tolyl) diazene.

Subject matter two

The invention also provides a preparation method of the azobenzene derivative, which comprises the following steps:

(1) adding p-methylaniline and concentrated hydrochloric acid into a flask, mixing, adding distilled water, and dropwise adding NaNO at 0-5 DEG C₂Continuously stirring the solution to obtain a diazonium salt solution of the p-methylaniline;

(2) mixing phenol and Na₂CO₃And sodium hydroxide, adding water to dissolve, dropwise adding the mixture into the diazonium salt solution of p-methylaniline obtained in the step (1), continuously stirring at room temperature, after the reaction is finished, regulating the pH value to 7 by using hydrochloric acid, filtering a precipitated product, washing with water, drying at room temperature in vacuum, and purifying by using a chromatographic column to obtain p-hydroxymethylazobenzene;

(3) heating p-hydroxy methyl azobenzene and R-Br in a solvent in the presence of sodium hydroxide for reaction, and purifying by a chromatographic column after the reaction is finished to obtain the product.

As some preferred embodiments of the present invention, the concentration of concentrated hydrochloric acid in said step (1) is 37%, the ratio of p-methylaniline and concentrated hydrochloric acid is 1mmol (0.20-0.50mL), p-methylaniline and NaNO₂The molar ratio of (1) to (1.0-1.5).

As some preferred embodiments of the present invention, in the step (2), phenol, Na₂CO₃And sodium hydroxide is 1 (1.0-1.5) to 0.8-1.3.

As some preferred embodiments of the present invention, the operation of the column purification in step (2) is: eluting impurities with petroleum ether and dichloromethane ═ 1 (1-5), eluting the product with dichloromethane, and performing rotary evaporation to obtain the p-hydroxy methyl azobenzene.

As some preferred embodiments of the present invention, the molar ratio of p-hydroxymethylazobenzene, R-Br and sodium hydroxide in the step (3) is 1 (1-5) to (1-3).

As some preferred embodiments of the present invention, the solvent of the step (3) is absolute ethanol: water is mixed solution of (5-30):1(V/V), heating temperature is 50-90 deg.C, eluent for chromatographic purification is dichloromethane and petroleum ether is 1: (2-5).

Subject three

The invention also provides an azobenzene solar thermal energy fuel film composite material which consists of the compound in the technical subject I and a flexible fabric.

As some preferred embodiments of the present invention, it is prepared by the following method: uniformly spreading the solid azo-based solar thermal fuel compound on a flexible fabric, placing the fabric in a dark closed environment, irradiating by using an ultraviolet lamp, and immersing the azo-based solar thermal fuel compound into the fabric when the azo-based solar thermal fuel compound is converted into a liquid state, thus obtaining the flexible film composite material.

The fabric is a flat soft piece block formed by crossing, winding and connecting fine and flexible objects. Including but not limited to: cotton-type fabrics, commercially referred to as "cotton" for short, are fabrics woven from cotton yarn or cotton and chemical fiber blended yarns; wool-type fabric, commercially abbreviated as "woolen cloth", which is a fabric woven from animal wool and wool-type chemical fibers; silk type fabrics, commercially referred to as "silk" for short, are called silk broadcloth by a fabric woven from mulberry silk, and tussah silk by a fabric woven from tussah silk; hemp type fabrics, mainly ramie fabrics and linen fabrics; purified fiber fabrics mainly comprise medium-long fiber cotton-like fabrics, linen-like fabrics, wool-like fabrics, silk-like fabrics, chemical fiber filament fabrics, artificial deerskin and artificial fur; nylon; carbon cloth, and the like.

Subject four

The last aspect of the invention provides an application of the azobenzene-based solar thermal energy fuel film composite material as a solar thermal energy storage material.

Adopt the produced beneficial effect of above-mentioned technical scheme to lie in:

at normal temperature, the cis-form conformation of the azobenzene derivative is liquid, the trans-form conformation of the azobenzene derivative is solid, and the azobenzene molecular energy storage density can be improved by combining the internal energy of the molecule and the latent heat of phase state change.

The solar thermal energy fuel film composite material provided by the invention is formed by combining and processing the azobenzene derivative and a flexible fabric through the characteristic that the azobenzene derivative generates phase state change through ultraviolet irradiation, and because the cis conformation of the used azobenzene derivative is liquid, more free volume is provided for further photoisomerization, and harmonic positive feedback is formed, the charging time is greatly reduced, and because the used flexible fabric has a flat and compact surface, is porous, has good mechanical flexibility and strong corrosion resistance, has stronger absorptivity, is tightly combined with the immersed azobenzene derivative, and has stronger solar thermal energy storage characteristic. The processing and manufacturing can be finished by ultraviolet irradiation, and the complicated operation and cost in the process of changing the high-temperature heating into the molten state are saved.

The solar thermal energy fuel film composite material provided by the invention has the characteristics of smooth and compact surface, environmental friendliness, rich sources, simplicity in operation, high response speed, good mechanical flexibility and strong reversibility, and is verified to have the highest energy density of more than 200J/g, thereby being very suitable for preparing novel clean energy and solar thermal energy fuel.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a nuclear magnetic spectrum of an azobenzene derivative obtained in example 2 of the present invention;

FIG. 2 is a nuclear magnetic spectrum of an azobenzene derivative obtained in example 5 of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail and fully with reference to the following embodiments.

EXAMPLE 1 preparation of p-hydroxymethylazobenzene

P-methylaniline (10mmol,1equiv) and high-concentration hydrochloric acid (37%, 2.5mL) were mixed in a 100mL round-bottom flask, and distilled water (10mL) was further added, and the round-bottom flask was put into an ice water bath and stirred. Weighing NaNO₂(690mg,10mmol,1equiv) was placed in a 50mL beaker, and 1.5mL of distilled water was added thereto to dissolve it, and then the solution was slowly poured into the above round-bottomed flask and stirred for 4 hours. Phenol (940mg,10mmol,1equiv), Na were then weighed₂CO₃(1.092mg,10.3mmol,1.03equiv) and sodium hydroxide (400mg,10mmol,1equiv) were dissolved in 50mL beaker by adding 10mL distilled water, then added drop by drop to round bottom flask and stirred at room temperature for 4 hours. After adjusting the pH to 7 with hydrochloric acid, the precipitated product is filtered off, washed with water (3X 20mL) and dried in vacuo at room temperature for 24 h. Then the dried solid is loaded into a chromatographic column, and the reaction is carried out by using petroleum ether: 1-dichloromethane: 1, passing a first mixed point, then passing a product point by dichloromethane, and carrying out rotary evaporation to obtain the p-hydroxymethylazobenzene with the yield of 61.3 percent and the MS (m/z) of 212.1.

Example 21- (4- (isopentyloxy) phenyl) -2- (p-tolyl) diazene (C)₁₈H₂₂N₂O) preparation

P-hydroxymethylazobenzene (1060mg,5mmol,1equiv), 1-bromo 3-methylbutane (2266mg,15mmol,3equiv) and sodium hydroxide (400mg,10mmol,2equiv) were weighed into a 100mL round bottom flask, to which 45mL absolute ethanol and 5mL distilled water were added, then the round bottom flask was put into an oil bath and heated to 70 ℃, and the condensed water was circulated and stirred for 24 h. Then adding a proper amount of silica gel, performing rotary evaporation to obtain a solid, filling the solid into a chromatographic column, and performing separation by using dichloromethane: petroleum ether is 1: 3 the product was spotted and rotary evaporation was carried out to give 1- (4- (isopentyloxy) phenyl) -2- (p-tolyl) diazene in 71% yield, MS (m/z) 282.1.¹H NMR(500MHz,CDCl₃,δ):7.91-7.87(d,2H,Ar-H),7.81-7.77(d,2H,Ar-H),7.32-7.28(d,2H,Ar-H),7.02-6.98(d,2H,Ar-H),4.09-4.05(t,2H,O-CH₂),2.44-2.41(s,3H,-CH₃),1.91-1.79(m,1H,-CH),1.75-1.69(q,2H,-CH₂),1.01-0.97(d,6H,-CH₃)。

Example 31- (4- (2-Methylbutoxy) phenyl) -2- (p-tolyl) diazene (C)₁₈H₂₂N₂O) preparation

P-hydroxymethylazobenzene (1060mg,5mmol,1equiv), 1-bromo-2-methylbutane (2266mg,15mmol,3equiv) and sodium hydroxide (400mg,10mmol,2equiv) were weighed into a 100mL round bottom flask, to which was added 45mL of anhydrous ethanol and 5mL of distilled water, the round bottom flask was then placed in an oil bath and heated to 70 ℃, the condensed water was circulated, and stirred for 24 h. Then adding a proper amount of silica gel to carry out rotary evaporation to obtain a solid, loading the solid into a chromatographic column, passing a product point, and carrying out rotary evaporation to obtain the 1- (4- (2-methylbutoxy) phenyl) -2- (p-tolyl) diazene with the yield of 63 percent, and MS (m/z) 282.1.

Example 41- (4- (pent-2-yloxy) phenyl) -2- (p-tolyl) diazene (C)₁₈H₂₂N₂O) preparation

P-hydroxymethylazobenzene (1060mg,5mmol,1equiv), 2-bromopentane (2266mg,15mmol,3equiv) and sodium hydroxide (400mg,10mmol,2equiv) were weighed into a 100mL round bottom flask, 45mL of anhydrous ethanol and 5mL of distilled water were added thereto, and the round bottom flask was put into an oil bath and heated to 70 ℃, condensed water was circulated, and stirred for 24 hours. Then adding a proper amount of silica gel, performing rotary evaporation to obtain a solid, loading the solid into a chromatographic column, passing a product point, and performing rotary evaporation to obtain the 1- (4- (pent-2-yloxy) phenyl) -2- (p-tolyl) diazene with the yield of 71 percent and MS (m/z) 282.1.

Example 51- (4- (but-3-en-1-yloxy) phenyl) -2- (p-tolyl) diazene (C)₁₇H₁₈N₂O) preparation

P-hydroxymethylazobenzene (1060mg,5mmol,1equiv), 4-bromobut-1-ene (2025mg,15mmol,3equiv) and sodium hydroxide (400mg,10mmol,2equiv) were weighed into a 100mL round bottom flask, to which 45mL of anhydrous ethanol and 5mL of distilled water were added, and then the round bottom flask was put into an oil bath and heated to 70 ℃, condensed water was circulated, and stirred for 24 hours. Then adding a proper amount of silica gel, performing rotary evaporation to obtain a solid, loading the solid into a chromatographic column, passing a product point, and performing rotary evaporation to obtain the 1- (4- (butyl-3-alkene-1-oxyl) phenyl) -2- (p-tolyl) diazene, wherein the yield is 72 percent, and the MS (m/z) 266.1.¹H NMR(500MHz,CDCl3,δ):7.92-7.88(d,2H,Ar-H),7.81-7.77(d,2H,Ar-H),7.32-7.28(d,2H,Ar-H),7.03-6.99(d,2H,Ar-H),5.98-5.88(m,1H,＝CH),5.23-5.18(d,1H,＝CH),5.16-5.12(d,1H,＝CH),4.12-4.08(t,2H,O-CH₂),2.62-2.56(q,2H,-CH₂),2.45-2.42(s,3H,-CH₃).

Example 61- (4- ((but-2-en-1-yl) oxy) phenyl) -2- (p-tolyl) -e) Diazene (C)₁₇H₁₈N₂O) preparation

P-hydroxymethylazobenzene (1060mg,5mmol,1equiv), 1-bromobut-2-ene (2025mg,15mmol,3equiv) and sodium hydroxide (400mg,10mmol,2equiv) were weighed into a 100mL round bottom flask, to which 45mL of anhydrous ethanol and 5mL of distilled water were added, and then the round bottom flask was put into an oil bath and heated to 70 ℃, condensed water was circulated, and stirred for 24 hours. Then adding a proper amount of silica gel, performing rotary evaporation to obtain a solid, loading the solid into a chromatographic column, passing through a product point, and performing rotary evaporation to obtain the 1- (4- ((butyl-2-alkene-1-group) oxy) phenyl) -2- (p-tolyl) diazene, wherein the yield is 68 percent, and the MS (m/z) is 266.1.

Example 71- (4- (neopentyloxy) phenyl) -2- (p-tolyl) diazene (C)₁₈H₂₂N₂O) preparation

P-hydroxymethylazobenzene (1060mg,5mmol,1equiv), 1-bromo-2, 2-dimethylpropane (2266mg,15mmol,3equiv) and sodium hydroxide (400mg,10mmol,2equiv) were weighed into a 100mL round bottom flask, to which 45mL of anhydrous ethanol and 5mL of distilled water were added, then the round bottom flask was put into an oil bath and heated to 70 ℃, and the condensed water was circulated and stirred for 24 hours. Then adding a proper amount of silica gel to be subjected to rotary evaporation to form a solid, loading the solid into a chromatographic column, passing a product point, and carrying out rotary evaporation to obtain the 1- (4- (neopentyloxy) phenyl) -2- (p-tolyl) diazene with the yield of 70 percent, and MS (m/z) 282.1.

Example 81- (4- ((1-buten-1-yl) oxy) phenyl) -2- (p-tolyl) diazene (C)₁₇H₁₈N₂O) preparation

P-hydroxymethylazobenzene (1060mg,5mmol,1equiv), 2-bromobut-2-ene (2025mg,15mmol,3equiv) and sodium hydroxide (400mg,10mmol,2equiv) were weighed into a 100mL round bottom flask, to which 45mL of anhydrous ethanol and 5mL of distilled water were added, and then the round bottom flask was put into an oil bath and heated to 70 ℃, condensed water was circulated, and stirred for 24 hours. Then adding a proper amount of silica gel, performing rotary evaporation to obtain a solid, loading the solid into a chromatographic column, passing a product point, and performing rotary evaporation to obtain the 1- (4- ((1-butene-1-yl) oxy) phenyl) -2- (p-tolyl) diazene with the yield of 61 percent and the MS (m/z) 266.1.

Example 91- (4- ((2-methylpropan-1-en-1-yl) oxy) phenyl) -2- (p-tolyl) diazene (C)₁₇H₁₈N₂O) preparation

P-hydroxymethylazobenzene (1060mg,5mmol,1equiv), 2-bromobut-2-ene (2025mg,15mmol,3equiv) and sodium hydroxide (400mg,10mmol,2equiv) were weighed into a 100mL round bottom flask, to which 45mL of anhydrous ethanol and 5mL of distilled water were added, and then the round bottom flask was put into an oil bath and heated to 70 ℃, condensed water was circulated, and stirred for 24 hours. Then adding a proper amount of silica gel, performing rotary evaporation to obtain a solid, loading the solid into a chromatographic column, passing a product point, and performing rotary evaporation to obtain the 1- (4- ((2-methylpropane-1-en-1-yl) oxy) phenyl) -2- (p-tolyl) diazene, wherein the yield is 69 percent, and the MS (m/z) 266.1.

Example 10 preparation of solar thermal Fuel film composite

A square fabric (cotton cloth, thickness about 1 μm) having a side length of 3cm was cut with scissors, and placed in a glass disk, and 50mg of a photoresponsive azobenzene derivative was weighed and uniformly spread on the square fabric. And then placing the glass disc in a dark closed environment, fixing an ultraviolet lamp on an iron support, irradiating the square fabric, and irradiating for two hours to obtain the flexible composite material solar heat energy fuel film.

Examples of the experiments

The solar thermal fuel film composite material was prepared by using the isopentyloxymethyl azobenzene obtained in example 2 according to the method of example 10, and the energy density of the composite material and the isopentyloxymethyl azobenzene obtained in example 2 were measured, respectively, and the experimental result showed that the energy density of the isopentyloxymethyl azobenzene was 181.63J/g and the energy density of the solar thermal fuel film was 200J/g. Indicating increased energy storage capacity in combination with the flexible fabric.

When the solar thermal fuel film composite material is irradiated by 355nm ultraviolet light, energy is stored in a chemical bond due to photoinduced trans-conformation → cis-conformation conversion, and the stored energy is gradually increased along with the prolonging of irradiation time and does not change after 2 h. Then, under the condition of light, the energy is gradually released in the form of heat, and the energy is completely released after 48 hours. The reversible change of the photoresponsive molecule does not obviously attenuate after 5 times of circulation.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.