CN110746774B

CN110746774B - Renewable two-dimensional composite membrane, and preparation method and application thereof

Info

Publication number: CN110746774B
Application number: CN201810815717.XA
Authority: CN
Inventors: 黄又举; 陈涛; 宋丽平; 陈黎明
Original assignee: Ningbo Institute of Material Technology and Engineering of CAS
Current assignee: Ningbo Institute of Material Technology and Engineering of CAS
Priority date: 2018-07-24
Filing date: 2018-07-24
Publication date: 2021-10-26
Anticipated expiration: 2038-07-24
Also published as: CN110746774A

Abstract

The invention discloses a renewable two-dimensional composite membrane, a preparation method and application thereof. The preparation method comprises the following steps: providing a first ligand, a second ligand and a gold source, wherein the first ligand is provided with a reducing functional group capable of being combined with the gold source, and the second ligand is capable of carrying out chemical crosslinking reaction with the reducing functional group and self-polymerization reaction; reducing the gold source in situ by the first ligand to form nano gold particles with surfaces rich in reducing functional groups; and enabling the second ligand to generate self-polymerization reaction at a water/air interface, and enabling the second ligand and the reducing functional group to generate chemical crosslinking reaction at the water/air interface, so as to form the reproducible two-dimensional composite membrane. The renewable two-dimensional composite membrane has the advantages of controllable area, good stability, easy transfer, good self-supporting performance and renewable performance, can be used for constructing a humidity sensor, and is used for driving a lamp switch by utilizing humidity-light heat and monitoring human health indexes in real time.

Description

Renewable two-dimensional composite membrane, and preparation method and application thereof

Technical Field

The invention relates to a nano particle/polymer composite material, in particular to a renewable two-dimensional composite film of nano gold-PEI-dopamine, a preparation method thereof and application thereof in a humidity sensor for monitoring human health indexes, belonging to the technical field of nano particle/polymer composite materials and the application field.

Background

The two-dimensional single-layer nanogold film has potential application in a plurality of fields, such as photoelectric devices, sensing, catalysis, Surface Enhanced Raman Spectroscopy (SERS) and the like. Therefore, the related research of the two-dimensional monolayer nano gold film is very important. To date, the methods for preparing two-dimensional monolayer gold nanoparticles are mainly Langmuir-Blodgett (LB) method (chem.Res.,2007,40,393-401), solvent evaporation method (nat. Mater.,2006,5,265-270), electrophoretic deposition method (Langmuir,2013,29,4242-4251), and block copolymer assembly method (ACS appl.Mater. interfaces,2016,8, 22705-22713). Although the method for preparing two-dimensional nano gold film has advanced greatly in recent decades, these traditional methods are generally complicated and time-consuming, and it is difficult to obtain a single-layer nano gold film with large area. Therefore, a simple and effective method for preparing a high-quality and large-area nano-gold single-layer film is urgently needed to be found.

Recently, the interface assembly method is a bottom-up method, which can efficiently construct a two-dimensional nanogold single-layer film, and has attracted the attention of a great number of researchers. Yogov et al first reported that silver nanoparticles self-assemble at the methylene chloride/water interface to form liquid metal films (J. Phys. chem.,1988,92, 5754-one 5760). The assembling method is carried out at the interface of two mutually incompatible phases, and is also suitable for the construction of two-dimensional nano particle monolayer films of other kinds. However, the nano gold film assembled at the interface has the defects of weak acting force between particles, easy breakage and difficult transfer, and influences the practical application of the nano gold film. The area of the macroscopic two-dimensional nanogold single-layer film is difficult to regulate and control, so that the repeatability is poor. In addition, the interfacial assembly method requires the use of volatile organic solvents (such as toluene, amyl alcohol, hexane, etc.) as an oil phase immiscible with water, resulting in environmental pollution and affecting the physical health of operators.

Disclosure of Invention

The invention mainly aims to provide a renewable two-dimensional composite membrane and a preparation method thereof, so as to overcome the defects in the prior art.

Another object of the present invention is to provide the use of said renewable two-dimensional composite membrane.

In order to achieve the purpose, the technical scheme adopted by the invention comprises the following steps:

among some embodiments of the present invention is a method of making a renewable two-dimensional composite membrane, comprising:

providing a first ligand, a second ligand and a gold source, wherein the first ligand has reducibility and has a reducing functional group capable of being combined with the gold source, and the second ligand can perform a chemical crosslinking reaction with the reducing functional group and can perform a self-polymerization reaction;

reducing the gold source in situ by using the first ligand as a reducing agent and a stabilizing agent to form nano gold particles with surfaces rich in reducing functional groups; and enabling the second ligand to generate self-polymerization reaction at a water/air interface, and enabling the second ligand and the reducing functional group on the surface of the nano gold particle to generate chemical crosslinking reaction at the water/air interface, so that self-assembly of the macroscopic two-dimensional nano gold single-layer film is induced, and a uniform and compact reproducible two-dimensional composite film is formed.

Also provided in some embodiments of the invention are regenerable two-dimensional composite membranes prepared by the foregoing methods.

Also provided in some embodiments of the present invention is a renewable two-dimensional composite membrane characterized by: the reproducible two-dimensional composite membrane is a gold nanoparticle single-layer membrane, and comprises a plurality of gold nanoparticles and a cross-linked network structure, wherein the cross-linked network structure is formed by chemical cross-linking reaction of a reducing functional group on the surface of the gold nanoparticles and a second ligand, and the surface of the gold nanoparticles is coated with a coating film layer formed by self-polymerization reaction of the second ligand.

Also provided in some embodiments of the present invention is the use of the aforementioned renewable two-dimensional composite film in the field of humidity sensing.

Also provided in some embodiments is a humidity sensing device comprising an electrode, and the aforementioned renewable two-dimensional composite film disposed in close proximity to the electrode.

Also provided in some embodiments of the present invention is a method of constructing a humidity sensor apparatus, comprising:

providing an electrode, and providing a plurality of electrodes,

and attaching the renewable two-dimensional composite film on the electrode to obtain the humidity sensing device.

Some embodiments of the invention further provide applications of the humidity sensing device in the field of visual health real-time monitoring or respiratory sensing mask preparation.

Also provided in some embodiments of the present invention is a humidity sensing device comprising the aforementioned renewable two-dimensional composite film or humidity sensing apparatus.

Compared with the prior art, the invention has the advantages that:

1) the preparation method of the reproducible two-dimensional composite membrane provided by the invention utilizes an in-situ reduction principle to directly reduce the gold nanoparticles in situ through the first ligand with reducing property; preparing a reproducible and self-supporting two-dimensional composite membrane by utilizing the self-oxidative polymerization performance of the second ligand and the chemical crosslinking action of the second ligand and the reducing functional group on the surface of the nanogold;

2) the renewable two-dimensional composite film prepared by the invention is a two-dimensional nanogold single-layer film, has controllable area, good stability and easy transfer, and has good self-supporting performance and renewable performance;

3) the invention fully utilizes the checking advantages of the polymer and the gold nanoparticles, combines the composite membrane with the electrode prepared in advance, constructs the humidity sensor with electrochemical signal response, has reference significance for the actual application occasion needing the air-isolated automatic control circuit, can be applied to the visual healthy real-time detection of human body sweat, respiration and the like, and can be applied to the visual healthy real-time detection of human body sweat, respiration and the like for the real-time monitoring of human body health indexes; moreover, the process is simple and controllable, the cost is low, and the large-scale implementation is facilitated.

Drawings

FIG. 1 is a schematic illustration of the preparation and humidity sensing of a regenerable two-dimensional composite membrane in an exemplary embodiment of the present invention.

Fig. 2 is a diagram illustrating a specific process for preparing a renewable two-dimensional composite membrane and the renewable performance in example 1 of the present invention.

FIG. 3 is a schematic diagram of the process of transferring the regenerable two-dimensional composite membrane prepared in example 1 of the present invention from a petri dish to a solid substrate or liquid surface.

Fig. 4a to 4c are schematic structural diagrams of the humidity sensor based on the renewable two-dimensional composite membrane prepared in example 1 of the present invention and data graphs for monitoring human health index, respectively.

Detailed Description

The technical solution of the present invention will be explained in more detail below. It is to be understood, however, that within the scope of the present invention, the above-described features of the present invention and those specifically described below (e.g., in the examples) may be combined with one another to form new or preferred embodiments. Not to be reiterated herein, but to the extent of space.

As described above, in view of the defects of the prior art, the inventor of the present invention has made extensive and intensive studies and extensive practices for a long time to provide a technical solution of the present invention, which is mainly based on the self-supporting and renewable performance of the renewable two-dimensional composite film and the hydrogen bonding between the composite film and water molecules, and when the external humidity changes, the electrical signal of the constructed humidity sensor also changes correspondingly, thereby achieving the purpose of monitoring the humidity.

In order to realize controllable assembly of a flexible macroscopic nano gold single-layer film, the inventor develops a method for inducing interfacial self-assembly by chemical crosslinking, utilizes a high-molecular surface ligand, such as hyperbranched Polyethyleneimine (PEI), to reduce a gold source such as chloroauric acid in situ to synthesize nano gold with surfaces rich in reductive functional groups such as amino groups, and induces assembly of the nano gold single-layer film by chemical crosslinking reaction of a second ligand such as dopamine and the amino groups on the surfaces of gold nanoparticles on a water/air interface.

In more detail, the method firstly utilizes a first ligand with reducing property, such as PEI, to reduce the nanogold in situ, and leads the surface of the nanogold to be provided with reducing functional groups, such as amino and the like; the chemical crosslinking action of the amino on the surface of the nano-gold and second ligands such as dopamine and the self-polymerization reaction of the dopamine enable the nano-gold-dopamine renewable composite membrane to be obtained under mild conditions; furthermore, the composite membrane is combined with a pre-prepared electrode to construct a nano gold-dopamine humidity sensor with electric signal response, and the nano gold-dopamine humidity sensor is used for monitoring human health indexes in real time.

The technical solution, the implementation process and the principle thereof will be further explained with reference to the drawings.

One aspect of an embodiment of the present invention provides a method for preparing a renewable two-dimensional composite film, including:

In some preferred embodiments, the preparation method specifically comprises:

carrying out in-situ reduction on a first reaction system containing a first ligand and a gold source solution to form nano gold particles with surfaces rich in reducing functional groups;

and adding a second ligand solution into the first reaction system to form a second reaction system, standing for more than 2-12 hours to enable the second ligand to generate self-polymerization reaction at a water/air interface, and enabling the second ligand and the reducing functional groups on the surfaces of the nano gold particles to generate chemical crosslinking reaction at the water/air interface to form the reproducible two-dimensional composite membrane.

In some embodiments, the reducing functional group includes, but is not limited to, amino, hydroxyl, and the like.

Further, the gold source includes chloroauric acid, but is not limited thereto.

Further, in order to make the gold source solution such as chloroauric acid be reduced under relatively mild conditions and further be used for chemical crosslinking reaction with the second ligand, the first ligand must have strong reducibility and have a reducing functional group capable of binding with the chloroaurate, such as amino or hydroxyl, and the materials can be selected and not limited to: the polyamine molecule, such as polyethyleneimine or polyacrylamide, is preferably hyperbranched Polyethyleneimine (PEI), and the mass average molecular weight thereof is preferably 200 to 100000.

Meanwhile, in order to make the composite membrane have the performances of renewability, strong self-supporting property, easy transfer and the like, the second ligand must be capable of performing a cross-linking action with a reducing functional group such as an amino group on the surface of the nanogold and performing a self-polymerization reaction, and the composite membrane can be selected from but not limited to the following materials: catecholamines such as dopamine or norepinephrine, etc., but are not limited thereto.

Dopamine is a mussel bionic protein and can generate self-polymerization reaction under the aerobic condition. Generally, oxygen is much more abundant at the water/air interface than in aqueous dopamine solution, so that the self-polymerization reaction rate at the water/air interface is faster than in aqueous solution, and a polydopamine film (PDA) is easily formed at the interface. Based on the self-polymerization behavior of a dopamine water/air interface (adv. mater. interfaces,2016,3,1600170), functionalized gold nanoparticles are combined with dopamine to construct a two-dimensional self-supporting nano-gold single-layer film. The area of the membrane can be precisely controlled by the size of the container used. More importantly, the PDA film can be repeatedly self-polymerized to form a film under the aerobic condition when being damaged, the newly formed film is firmly cross-linked with the original film, and the PDA film has the functions of regeneration and self-healing (ACS Nano,2016,10, 1317-doped 1324), so that the PDA-coated gold nanoparticle film realizes the function of repeated regeneration for many times. And, because nanometer gold utensil has higher photothermal effect, and dopamine has humidity sensing characteristic, combines the two advantages, can design into humidity-light and heat switch with this membrane to be applied to motion bracelet.

In some more preferred embodiments, as shown in fig. 1, the preparation method may comprise the steps of:

(1) providing a suitable environment for growing the nano-gold, wherein the environment comprises a chloroauric acid solution with a certain concentration and a first ligand PEI solution with reducing performance, and a suitable reaction temperature;

(2) under a proper temperature, nano gold particles (also called PEI functionalized gold nanoparticles) with amino groups on the surface are grown in situ through the reducibility of PEI;

(3) providing proper conditions for assembling the nano-gold, including a dopamine hydrochloride solution with a certain concentration and a proper pH environment; and (3) under the condition of a set temperature, mixing the nano gold particles with amino groups on the surfaces obtained in the step (2) with dopamine hydrochloride with a certain concentration in a proper pH environment, pouring the mixed solution on the surface of a glassware, standing for more than 2-12 h in a room temperature environment, and naturally generating the nano gold-PEI-dopamine composite membrane on a water-air interface.

(4) And (3) utilizing the self-supporting property and the regenerability of the composite membrane, and cutting and transferring the composite membrane obtained in the step (3) at will.

Further, the setting of the temperature condition in step (1), i.e. the temperature of the in-situ reduction, includes: and (3) keeping the temperature at 60-80 ℃.

Furthermore, the concentration of the nano-gold particles formed in the first reaction system (i.e. the nano-gold solution obtained in step (1)) is 0.1-20 mmol/L.

Further, the second reaction system is an alkaline system, and the pH value is 7-14.

Further, the second reaction system also comprises a tris buffer solution with the concentration of 0.1-2000 mmol/L.

Further, the concentration of the second ligand in the second ligand solution (i.e., the concentration of dopamine in step (3)) is 0.1-20 mg/mL.

In some embodiments, the method of making comprises: the self-polymerization reaction or the chemical crosslinking reaction is carried out at room temperature (more than 2-12 h) or at a temperature higher than room temperature or under the condition of ultraviolet irradiation; wherein the reaction is accelerated by heat or ultraviolet light.

In some embodiments, the method of making further comprises: after the formed renewable two-dimensional composite membrane is transferred, a renewable two-dimensional composite membrane can be repeatedly regenerated at a water/air interface.

In conclusion, the preparation method of the reproducible two-dimensional composite membrane provided by the invention utilizes the in-situ reduction principle to directly reduce the gold nanoparticles in situ through the first ligand with the reduction performance; and preparing the reproducible and self-supporting two-dimensional composite membrane by utilizing the self-oxidative polymerization performance of the second ligand and the chemical crosslinking action of the second ligand and the reducing functional group on the surface of the nanogold.

Another aspect of an embodiment of the present invention also provides a renewable two-dimensional composite membrane prepared by the foregoing method.

Another aspect of the embodiments of the present invention also provides a renewable two-dimensional composite film, which is a single-layer film of gold nanoparticles, and includes a plurality of gold nanoparticles and a cross-linked network structure, where the cross-linked network structure is formed by chemically cross-linking a reductive functional group on the surface of the gold nanoparticle and a second ligand, and the surface of the gold nanoparticle is coated with a coating film layer formed by self-polymerization of the second ligand.

Further, the thickness of the reproducible two-dimensional composite film is more than 20nm, preferably 20-1000 nm, particularly preferably 20nm to hundreds of nanometers, and the formed film can be thickened according to different reaction conditions.

Furthermore, the size of the nano gold particles is 10-30 nm.

Further, the reducing functional group is derived from a first ligand, so that a gold source solution such as chloroauric acid can be reduced under relatively mild conditions and can be further used for a chemical crosslinking reaction with a second ligand, the first ligand must have relatively strong reducing property and carry a reducing functional group capable of binding with a chloroaurate group, such as an amino group or a hydroxyl group, and the materials can be selected from but are not limited to: the polyamine molecule, such as polyethyleneimine or polyacrylamide, is preferably hyperbranched Polyethyleneimine (PEI), and the mass average molecular weight thereof is preferably 200 to 100000.

In some more specific embodiments, the composite membrane is a nanogold-PEI-dopamine regenerable two-dimensional composite membrane. In the gold nanoparticle-PEI-dopamine reproducible two-dimensional composite membrane:

the surface of the nano-gold is modified by a first ligand PEI, and the ligand is a reducing agent for the growth of the nano-gold;

the self-polymerization reaction of the amino on the surface of the nano-gold and the dopamine is a sufficient condition for obtaining the nano-gold-dopamine composite membrane;

the stable chemical crosslinking effect of the amino on the surface of the nano-gold and the dopamine ensures that the nano-gold-dopamine composite membrane has the advantages of controllable area, good stability, easy transfer and the like.

Further, the reproducible two-dimensional composite film has good self-supporting properties, can be transferred to different liquid and solid surfaces, and can be arbitrarily tailored and patterned.

Furthermore, due to the renewable performance of dopamine, after the nano gold film is transferred, the solution can be repeatedly regenerated to form a layer of nano gold film under the aerobic condition, so that the renewable unique performance is realized.

In conclusion, the renewable two-dimensional composite film prepared by the invention is a two-dimensional nanogold single-layer film, has controllable area, good stability and easy transfer, and has good self-supporting performance and renewable performance.

Another aspect of the embodiments of the present invention also provides an application of the renewable two-dimensional composite film in the humidity sensing field.

Specifically, the invention combines the higher photo-thermal conversion efficiency of the nano-gold and the humidity sensing performance of the composite film to construct a quick-response humidity sensor, and the humidity-photo-thermal is utilized to drive a lamp switch. When the humidity reaches a certain amount, the bulb is automatically turned on, and when the water molecules are evaporated by illumination or temperature rise, the bulb is automatically extinguished.

And, because nanometer gold utensil has higher photothermal effect, and dopamine has humidity sensing characteristic, combines the two advantages, can design into humidity-light and heat switch with this membrane to be applied to motion bracelet.

Correspondingly, the embodiment of the invention also provides a humidity sensing device, which comprises an electrode and the reproducible two-dimensional composite film, wherein the reproducible two-dimensional composite film is attached to the electrode. The invention is applied to a humidity sensing device, and a current path is formed between nano gold and water molecules, so that an electric signal is generated.

Accordingly, another aspect of the embodiments of the present invention also provides a method for constructing a humidity sensing apparatus, including:

providing an electrode, and providing a plurality of electrodes,

Furthermore, the electrodes comprise interdigitated Ni/Au interdigitated electrodes (IDE) which are formed by depositing on a flexible substrate such as polyimide by sputtering.

Further, the relevant data acquisition of the humidity sensing device test is connected to a computer, and the test is carried out by utilizing an electrochemical workstation.

Further, another aspect of the embodiments of the present invention also provides practical applications of the humidity sensing device, for example, applications in the field of visual health real-time monitoring or respiratory sensing mask preparation.

The bulb switch based on humidity-photothermal stimulation has reference significance for practical application occasions needing the air-separating automatic control circuit, and meanwhile, the bulb switch can be designed and applied to visual healthy real-time detection of human sweat, respiration and the like.

And it is designed as a breathing sensing mask for monitoring different health states, such as sleeping, running, cold and breathing curve monitoring of normal states, and for breathing changes caused by different mood changes, such as crying, laughing and stress.

Accordingly, another aspect of the embodiments of the present invention also provides a humidity sensing device, which includes the renewable two-dimensional composite film or the humidity sensing apparatus.

By the technical scheme, the check advantages of the polymer and the gold nanoparticles are fully utilized, the composite membrane is combined with the electrode prepared in advance to construct the humidity sensor with electrochemical signal response, the humidity sensor has reference significance for practical application occasions needing an automatic control circuit for air isolation, and meanwhile, the humidity sensor can be designed to be applied to visual healthy real-time detection of human body sweat, respiration and the like, and can be simultaneously applied to visual healthy real-time detection of human body sweat, respiration and the like for real-time monitoring of human body health indexes; moreover, the process is simple and controllable, the cost is low, and the large-scale implementation is facilitated.

The technical solutions of the present invention are further explained below with reference to some preferred embodiments and the accompanying drawings, but the experimental conditions and the setting parameters should not be construed as limitations of the basic technical solutions of the present invention. And the scope of the present invention is not limited to the following examples.

Example 1: nano-gold-dopamine reproducible two-dimensional composite membrane humidity sensor, preparation method and application thereof

(1) Preparing PEI in-situ reduced nanogold: the PEI functionalized gold nanoparticles (PEI/AuNPs) are obtained by utilizing amino in PEI to reduce chloroauric acid in situ. First, PEI (69.4 m)g) Dissolved in deionized water (10mL) and 153. mu.L (0.1M) of HAuCl was added₄The aqueous solution is heated in an oil bath at 65 ℃ and rapidly stirred for 2 h. Storing the synthesized wine red PEI/AuNPs in a refrigerator at 4 ℃ for later use;

(2) preparing a nano gold-dopamine composite two-dimensional film: a75 mm diameter petri dish was charged with 15mL of deionized water, 40mg of dopamine hydrochloride was dissolved in deionized water, and 3mL of the above-synthesized PEI/AuNPs stock solution and 2mL of tris buffer (tris, 100mmol/L, pH 8.5) were added. Standing for more than 12h to form a film on the water/air interface. After half-transferring the membrane from the dish, the solution was able to self-assemble several times to form a new membrane and firmly bind to the old membrane (see FIG. 2). The membrane was transferred from the petri dish to a solid substrate or liquid surface (see fig. 3) and washed in deionized water to remove excess solution for characterization or for further experiments.

(3) Construction of humidity sensor: the interdigitated Ni/Au interdigitated electrodes (IDE) are fabricated by depositing on a Polyimide (PI) substrate by sputter coating. The Ni thickness was 3 μm and the Au thickness was 0.07. mu.m. The macroscopic size of the IDE electrode on the PI substrate is 13mm × 30 mm. The interdigital electrodes typically have a diameter of 150 μm width, a pitch of 150 μm electrodes, an electrode length of 11mm and a number of 42 electrodes. The prepared PDA/PEI/AuNPs membrane is vertically attached downwards by taking the electrode as a solid substrate, and then the humidity sensing experimental device is assembled (refer to figure 4). The relevant data acquisition in the humidity sensing test experiment is connected to a computer and the test is carried out by using an electrochemical workstation. The humidity and resistance curves were measured in a closed vacuum vessel at room temperature (about 25 deg.C) using saturated aqueous solutions of different humidities, each of which had CaCl₂·6H₂O、K₂CO₃、MgNO₃NaCl and K₂SO₄The corresponding humidities were 29%, 43%, 54%, 75% and 97%, respectively (see fig. 4).

Example 2: nano-gold-dopamine reproducible two-dimensional composite membrane humidity sensor, preparation method and application thereof

This embodiment is substantially the same as embodiment 1 except that:

step (1) in situ reduction of HAuCl by replacing PEI in example 1 with polyacrylamide₄The temperature of the aqueous solution was 60 ℃.

And (3) carrying out self-polymerization reaction of the dopamine and chemical crosslinking reaction of the dopamine and the reductive functional groups on the surfaces of the gold particles at room temperature, wherein the concentration of the gold nanoparticles is 0.1mmol/L, the concentration of the dopamine is 0.1mg/mL, and the concentration of the tris buffer solution is 0.1 mmol/L.

The construction and performance test of the humidity sensor in step (3) are substantially the same as those in example 1.

Example 3: nano-gold-dopamine reproducible two-dimensional composite membrane humidity sensor, preparation method and application thereof

This embodiment is substantially the same as embodiment 1 except that:

in-situ reduction of HAuCl in step (1)₄The temperature of the aqueous solution was 70 ℃.

And (3) carrying out self-polymerization reaction of the dopamine and chemical crosslinking reaction of the dopamine and the reductive functional groups on the surfaces of the gold particles at room temperature, wherein the concentration of the gold nanoparticles is 2mmol/L, the concentration of the dopamine is 2mg/mL, and the concentration of the tris buffer solution is 500 mmol/L.

Example 4: nanogold-norepinephrine renewable two-dimensional composite membrane humidity sensor, and preparation method and application thereof

This embodiment is substantially the same as embodiment 1 except that:

step (1) in situ reduction of HAuCl by replacing PEI in example 1 with polyacrylamide₄The temperature of the aqueous solution was 80 ℃.

And (2) replacing dopamine in example 1 with noradrenaline, wherein the self-polymerization reaction and the chemical crosslinking reaction of noradrenaline and the reducing functional groups on the surfaces of the gold particles are carried out under the ultraviolet irradiation condition, the concentration of the gold nanoparticles is 20mmol/L, the concentration of noradrenaline is 20mg/mL, and the concentration of the tris buffer solution is 2000 mmol/L.

In conclusion, the invention utilizes the principle of in-situ reduction to directly reduce the gold nanoparticles in situ through the first ligand with reducing performance; the renewable and self-supporting two-dimensional composite membrane is prepared by utilizing the oxidative self-polymerization performance of the second ligand and the chemical crosslinking effect of the second ligand and the reducing functional group on the surface of the nanogold, has controllable area, good stability, easy transfer, good self-supporting performance and renewable performance, can be used for constructing a humidity sensor, and is used for driving a lamp switch by utilizing humidity-light heat for monitoring the health index of a human body in real time.

In addition, the inventor also carries out corresponding tests by using other raw materials and other process conditions listed above to replace various raw materials and corresponding process conditions in the examples 1 to 4, and the obtained renewable two-dimensional composite membrane has ideal self-supporting performance, renewable performance and the like and is basically similar to the products of the examples 1 to 4.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and are not limited. Although the present invention has been described in detail with reference to the embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A preparation method of a reproducible two-dimensional composite film is characterized by comprising the following steps:

providing a first ligand, a second ligand and a gold source, wherein the first ligand has reducibility and has a reducibility functional group capable of being combined with the gold source, the first ligand is a polyamine molecule, the second ligand can perform a chemical crosslinking reaction with the reducibility functional group and can perform a self-polymerization reaction, the second ligand is a catecholamine molecule, and the gold source is chloroauric acid;

2. The method according to claim 1, comprising:

3. The production method according to claim 1 or 2, characterized in that: the first ligand comprises polyethyleneimine and/or polyacrylamide.

4. The production method according to claim 3, characterized in that: the first ligand is hyperbranched polyethyleneimine, and the mass-average molecular weight of the hyperbranched polyethyleneimine is 200-100000.

5. The production method according to claim 1 or 2, characterized in that: the second ligand comprises dopamine and/or norepinephrine.

6. The production method according to claim 1 or 2, characterized in that: the temperature of the in-situ reduction is 60-80 ℃.

7. The method of claim 2, wherein: the concentration of the nano gold particles with a certain concentration formed in the first reaction system is 0.1-20 mmol/L.

8. The method of claim 2, wherein: the pH value of the second reaction system is 7-14.

9. The method of claim 2, wherein: the second reaction system also comprises a trihydroxymethyl aminomethane buffer solution, and the concentration of the trihydroxymethyl aminomethane buffer solution in the second reaction system is 0.1-2000 mmol/L.

10. The method of claim 2, wherein: the concentration of the second ligand in the second ligand solution is 0.1-20 mg/mL.

11. The method of manufacturing according to claim 2, comprising: the self-polymerization reaction or the chemical crosslinking reaction is carried out under the condition of room temperature or the temperature higher than room temperature or under the condition of ultraviolet irradiation.

12. The method of manufacturing according to claim 2, further comprising: after the formed renewable two-dimensional composite membrane is transferred, a renewable two-dimensional composite membrane can be repeatedly regenerated at a water/air interface.

13. A regenerable two-dimensional composite membrane prepared by the method of any one of claims 1-12.

14. A regenerable two-dimensional composite membrane characterized by: the reproducible two-dimensional composite membrane is a gold nanoparticle single-layer membrane, and comprises a plurality of gold nanoparticles and a cross-linked network structure, wherein the cross-linked network structure is formed by chemical cross-linking reaction of a reducing functional group on the surface of the gold nanoparticles and a second ligand, and the surface of the gold nanoparticles is coated with a coating film layer formed by self-polymerization reaction of the second ligand, wherein the reducing functional group is derived from a first ligand, the first ligand has reducibility and has a reducing functional group, the first ligand is a polyamine molecule, and the second ligand is a catechol amine molecule.

15. The renewable two-dimensional composite membrane according to claim 14, wherein: the thickness of the reproducible two-dimensional composite film is more than 20 nm.

16. The renewable two-dimensional composite membrane according to claim 15, wherein: the thickness of the renewable two-dimensional composite film is 20-1000 nm.

17. The renewable two-dimensional composite membrane according to claim 14, wherein: the size of the nano gold particles is 10-30 nm.

18. The renewable two-dimensional composite membrane according to claim 14, wherein: the first ligand comprises polyethyleneimine and/or polyacrylamide.

19. The renewable two-dimensional composite membrane according to claim 18, wherein: the first ligand is hyperbranched polyethyleneimine, and the mass-average molecular weight of the hyperbranched polyethyleneimine is 200-100000.

20. The renewable two-dimensional composite membrane according to claim 14, wherein: the second ligand comprises dopamine and/or norepinephrine.

21. The renewable two-dimensional composite membrane according to claim 14, wherein: the renewable two-dimensional composite membrane has self-supporting performance and renewable performance.

22. Use of the renewable two-dimensional composite membrane of any one of claims 13 to 21 in the field of humidity sensing.

23. Use according to claim 22, characterized in that: the humidity sensing field comprises the humidity-photo-thermal switch field.

24. A humidity sensing device comprising an electrode and the renewable two-dimensional composite film of any one of claims 13-21 disposed in close proximity to the electrode.

25. A method of constructing a humidity sensor apparatus, comprising:

providing an electrode, and providing a plurality of electrodes,

attaching the renewable two-dimensional composite film of any one of claims 13-21 to the electrode to obtain a humidity sensing device.

26. The method of construction of claim 25, wherein: the electrodes comprise interdigitated Ni/Au electrodes.

27. The method of construction of claim 25, wherein: the electrode is formed by depositing on a substrate by a sputtering coating method.

28. The method of constructing as claimed in claim 27, wherein: the substrate comprises a polyimide flexible substrate.

29. Use of the humidity sensing device according to claim 24 in the manufacture of a respiratory sensing mask.

30. A humidity sensing device characterized by comprising the renewable two-dimensional composite film according to any one of claims 13 to 21 or the humidity sensing apparatus according to claim 24.