CN110317309B - Memristor based on two-dimensional polymer film and preparation method thereof - Google Patents

Abstract

The invention discloses a memristor based on a two-dimensional polymer film and a preparation method thereof. The preparation method comprises the following steps: dripping an aromatic polyaldehyde mixed solution on the liquid surface of the aromatic polyamine mixed solution, and at room temperature for 20 ℃ The aromatic organic solvent B in the aromatic polyaldehyde mixed solution is placed at ~25° C. to be completely volatilized, and a two-dimensional polymer film is obtained on the liquid surface. The invention uses aromatic polyaldehydes and aromatic polyamines as reaction monomers to prepare covalent organic two-dimensional polymer films for the first time, and provides growth conditions for preparing covalent organic two-dimensional polymers. The preparation method is simple and economical, does not require high-end precision instruments, and can obtain a large-area uniform two-dimensional polymer film without providing high energy. actual production needs.

Description

Memristor based on two-dimensional polymer film and its preparation method

technical field

The invention belongs to the technical field of organic two-dimensional materials, in particular to a memristor based on a two-dimensional polymer film and a preparation method thereof.

Background technique

The lateral dimension of two-dimensional materials is larger than 100 nm, or even a few microns or even larger, but the thickness is only a single atom or a few atoms thick (usually less than 5 nanometers). It is a periodic structure with regional repeating units inside. of polymer materials. In 2D materials, electrons are confined to two dimensions, enabling unprecedented physical, electronic and chemical properties. The first 2D material discovered was graphene exfoliated from graphite. As a two-dimensional material with a thickness of one atomic layer, graphene is composed of a hexagonal honeycomb lattice composed of sp ² hybridized carbon atoms. The large π-conjugated system formed based on this structure has excellent electronic properties. Transmission, optical, mechanical and thermal properties. The discovery of these excellent properties of graphene has aroused researchers' interest in rationally designing and synthesizing new two-dimensional polymers at the atomic or molecular level.

After further exploration by the researchers, two-dimensional covalent organic mesh materials (2D COFs) were discovered. This material is a new type of two-dimensional material with periodic structure and single structural unit thickness, which is composed of organic structural units linked by covalent bonds. The material is a monomer composed of "light elements" such as C, H, O, and N, and forms a very stable porous nanomaterial through strong covalent bonds between atoms. Therefore, the function of two-dimensional polymers can be regulated by adjusting the types and positions of monomer functional groups. Similar to graphene, conventional 2D polymers are obtained by exfoliating covalent organic frameworks (COFs) using a "top-down" approach. Due to the size of 2D organic grid framework materials (COFs), the area of 2D single crystal materials with a thickness of one atomic layer is greatly limited, making it difficult for 2D materials to meet the requirements of nanoelectronic devices. Another "bottom-up" approach is often used in the preparation of 2D materials. In this method, the monomer is first deposited on the surface of a suitable substrate material, and then a certain external stimulus is given to prepare a two-dimensional polymer through surface reaction. This method of preparing two-dimensional materials at the interface can make full use of the catalytic activity of the substrate and van der Waals epitaxy to prepare a single-layer two-dimensional polymer, and it is possible to obtain a large-area single-layer material. However, this method often requires some harsh conditions, such as high temperature, ultra-high vacuum environment, etc., to promote the reaction. In addition, the two-dimensional materials obtained by this method have the problem of difficult transfer. Two-dimensional materials prepared by either "top-down" or "bottom-up" methods are difficult to meet the needs of practical applications in terms of size and properties.

SUMMARY OF THE INVENTION

Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a memristor based on a two-dimensional polymer film. The preparation method of the two-dimensional polymer film is based on an interface method, and can be prepared in an atmospheric environment near room temperature. For ultrathin two-dimensional polymer films, two-dimensional polymer films with different thicknesses can be obtained by changing the concentration and molar amount of monomers (the ratio of aromatic polyaldehydes and aromatic polyamines) during the preparation process. The two-dimensional polymer film obtained by the preparation method of the present invention can be transferred to any desired substrate as required, which is beneficial to construct electronic devices (memristors) with different structures.

The purpose of the present invention is achieved through the following technical solutions.

A preparation method of a two-dimensional polymer film, comprising the following steps:

Add the aromatic polyaldehyde mixed solution dropwise to the liquid surface of the aromatic polyamine mixed solution, place it at room temperature of 20-25° C. until the aromatic organic solvent B in the aromatic polyaldehyde mixed solution is volatilized, and obtain on the liquid surface Two-dimensional polymer films, where,

The ratio of the amount of the aromatic polyaldehyde in the aromatic polyaldehyde mixed solution to the amount of the aromatic polyamine in the aromatic polyamine mixed solution (0.0015-0.005): 0.01389;

The configuration method of the aromatic polyamine mixed solution is as follows: evenly distributing the aromatic polyamine in the organic solvent A to obtain a solution A, adding deionized water to the solution A and uniformly mixing to obtain a light brown aromatic polyamine mixed solution A solution, wherein the concentration of the aromatic polyamine in the solution A is 0.185-4.63 mmol/mL, and the organic solvent A is an aprotic and water-miscible organic reagent;

The configuration method of the aromatic polyaldehyde mixed solution is as follows: evenly distributing the aromatic polyaldehyde in the aromatic organic solvent B to obtain a solution B, adding an organic acid to the solution B to obtain an aromatic polyaldehyde mixed solution, wherein the The ratio of the volume fraction of the aromatic organic solvent B to the material fraction of the aromatic polyaldehyde is (0.5～1): (0.0008～0.01), and the volume of the organic acid is the volume of the solution B 0.7 to 1.5% of the

The organic acid is acetic acid, trifluoroacetic acid or trifluoromethanesulfonic acid;

The aromatic organic solvent B is chlorobenzene, dichlorobenzene or toluene.

In the above technical solution, the organic solvent A is N,N-dimethylformamide, N,N-dimethylacetamide or dimethylsulfoxide.

In the above technical solution, the time for the aromatic organic solvent B placed in the aromatic polyaldehyde mixed solution to be completely volatilized is at least 24 hours.

In the above technical solution, in the aromatic polyamine mixed solution, the ratio of the volume fraction of the deionized water to the material fraction of the aromatic polyamine is 1: (0.005-0.03).

In the above technical solution, the unit of one of the parts by volume is mL, the unit of one of the parts by mass is mg, and the unit of one of the parts by quantity is mmol.

In the above technical solution, the aromatic polyaldehyde includes two or more aldehyde groups.

In the above technical solution, the aromatic polyamine includes two or more amine groups.

In the above technical solution, the deionized water is ultrapure water, and the resistivity is 18.2MΩ﹒ cm.

The two-dimensional polymer film obtained by the above preparation method.

In the above technical solution, the thickness of the two-dimensional polymer film is 2-80 nm.

The memristor obtained by using the above two-dimensional polymer film as the active layer.

In the above technical solution, the memristor is, from top to bottom, an active electrode, a two-dimensional polymer film and an inert electrode, the active electrode is an aluminum layer, a copper layer or a silver layer; the inert electrode is ITO Conductive glass layer, gold layer or platinum layer.

In the above technical solution, the thickness of the active electrode is 10-200 nm.

The preparation method of the above-mentioned memristor comprises the following steps:

a) Transfer the two-dimensional polymer film to the upper surface of the inert electrode, and vacuum dry it in a vacuum drying oven at 15-40° C. for 2-10 hours;

b) Evaporating the active electrode on the two-dimensional polymer film.

的速率沉积厚度为20～100nm的银层，沉积结束后取下所述铜网，完成蒸镀银层。In the step b), when the active electrode is a silver layer, the method for evaporating the silver layer is as follows: using a copper mesh as a mask to stick on the upper surface of the two-dimensional polymer film to

A silver layer with a thickness of 20-100 nm is deposited at a rate of 20 to 100 nm, and the copper mesh is removed after the deposition is completed to complete the vapor deposition of the silver layer.

In the above technical solution, the mesh number of the copper mesh is 200-300 mesh.

Application of the above-mentioned two-dimensional polymer films as active layers in memristors.

Compared with the prior art, the beneficial effects of the two-dimensional polymer film of the present invention are:

1. The present invention uses aromatic polyaldehydes and aromatic polyamines as reaction monomers to prepare covalent organic two-dimensional polymer films for the first time, and provides growth conditions for preparing covalent organic two-dimensional polymers. The preparation method is simple and economical, does not require high-end precision instruments, and can obtain a large-area uniform two-dimensional polymer film without providing high energy. actual production needs.

2. The present invention proposes to prepare a covalent organic two-dimensional polymer film at the water-air interface by solution epitaxy. At the same time, by virtue of the covalent connection of two monomers, it can not only provide a uniform pore-like structure, but also make the material Stable in a variety of organic solvents and water. Compared with one-dimensional polymer films obtained by spin coating, drop casting, etc., the material not only has a uniform pore structure, but also has good solvent resistance, which expands the application field of the material.

3. The present invention proposes to prepare the covalent organic two-dimensional polymer film at the water-air interface by solution epitaxy, showing an amorphous state, so that the two-dimensional polymer film exhibits the characteristics of flexibility and self-support.

4. The present invention provides a memristor with a two-dimensional polymer film as a functional layer for the first time. With the help of the porous structure of the material, an active electrode is used to prepare a memristor based on the principle of conductive filaments. Since the two-dimensional polymer film of the present invention is prepared on the gas-liquid interface, it is very convenient to transfer to any substrate. Other materials are transferred to the substrate by inorganic evaporation, spin coating and other methods. Our The method has the advantages of convenience and ease of operation, and can be transferred to any desired substrate.

Description of drawings

1 is a schematic structural diagram of a memristor of the present invention;

Fig. 2 is the characterization morphology of the two-dimensional polymer film of the present invention in the range of 10 μm × 10 μm, the thickness of the two-dimensional polymer film in 2(a) is 20 nm, and the thickness of the two-dimensional polymer film in 2(b) is 50 nm, and the thickness of the two-dimensional polymer film in 2(c) is 70 nm;

Fig. 3 is the turn-on and erasing curves of the memristor of the present invention (using a two-dimensional polymer film with a thickness of 20 nm);

Figure 4 is the statistics of the cycle stability of the memristor of the present invention (using a 20 nm thick two-dimensional polymer film);

Figure 5 shows the statistics of high and low resistance states of different devices (using a 20nm thick two-dimensional polymer film);

Figure 6 shows the retention time obtained by reading the memristor of the present invention with a voltage of 0.1V (using a two-dimensional polymer film with a thickness of 20 nm);

Figure 7 is the turn-on and erase curves of the memristor of the present invention (using a 50nm thick two-dimensional polymer film);

Figure 8 is the statistics of the cycle stability of the memristor of the present invention (using a 50 nm thick two-dimensional polymer film);

Figure 9 is the statistics of high and low resistance states of different devices (using a 50nm thick two-dimensional polymer film);

Figure 10 shows the retention time obtained by reading the memristor of the present invention with a voltage of 0.1V (using a two-dimensional polymer film with a thickness of 50nm);

Figure 11 is the turn-on and erase curves of the memristor of the present invention (using a 70nm thick two-dimensional polymer film);

Figure 12 is the statistics of the cycle stability of the memristor of the present invention (using a 70 nm thick two-dimensional polymer film);

Figure 13 shows the statistics of high and low resistance states of different devices (using a 2D polymer film with a thickness of 70 nm);

Figure 14 shows the retention time obtained by reading the memristor of the present invention with a voltage of 0.1V (using a two-dimensional polymer film with a thickness of 70 nm);

Figure 15 is a graph of nitrogen adsorption/desorption of two-dimensional polymer films;

Figure 16 is a pore size distribution diagram of a two-dimensional polymer film;

Fig. 17 is the Fourier transform infrared spectrum of the two-dimensional polymer film of the present invention;

18 is a high-resolution transmission electron microscope image of the two-dimensional polymer film prepared in Example 2;

FIG. 19 is a selected area electron diffraction image of the two-dimensional polymer film prepared in Example 2. FIG.

Detailed ways

In specific embodiments of the present invention, the involved instruments are as follows:

Atomic force microscope model: Bruker Dimension Icon ScanAsyst, Germany, the atomic microscope test adopts the tapping mode, and the probe is the Bruker VSEP-2A needle tip.

Optical microscope model: Carl Zeiss Axio Scope A1 pol

Electrical test probe station properties: Korea Ecopia EPS-1000

Semiconductor property tester: Shanghai Zaide EPS-300, when using the semiconductor property tester to test the performance of the device, ITO is grounded, and a voltage is applied to the Ag electrode with a step size of 0.02V. In the device property diagram, 1 refers to the curve of the applied voltage sweeping from 0V-1.5V, 2 refers to the curve that the applied voltage sweeps from 1.5-0V, and 3 refers to the curve that the applied voltage sweeps from 0-3.3V , 4 refers to the curve appearing from the applied voltage sweep from 3.3-0V.

BET test: JB-2020 specific surface area tester, during BET test, activated at 200℃, tested at 77K.

The sources of purchase of the medicines involved are:

All reagents used were purchased from Sinopharm Group, and the purity was of analytical grade.

In the following examples, the unit of a volume fraction is mL, the unit of a mass fraction is mg, and the unit of a substance fraction is mmol. Deionized water is ultrapure water with a resistivity of 18.2MΩ﹒ cm.

In the technical solution of the present invention, the reaction vessel can be a watch dish, a weighing bottle, a petri dish, a glass water tank or a glass jar, etc. According to the area of the reaction vessel, the area of the obtained two-dimensional polymer film can be 1 μm ² -1m ² . The following Examples 1 to 3 all use weighing bottles with a diameter of 7 cm as the reaction vessel. Therefore, the shapes of the two-dimensional polymer films of the following Examples 1 to 3 are all circles with a diameter of 7 cm. Example 4- The shapes of 6 are all cut into two-dimensional polymer films of 1*1 cm.

The technical solutions of the present invention are further described below in conjunction with specific embodiments.

Example 1

A preparation method of a two-dimensional polymer film, comprising the following steps:

Arrange the aromatic polyamine mixed solution in a weighing bottle with a diameter of 7cm, add the aromatic polyaldehyde mixed solution dropwise to the liquid surface of the aromatic polyamine mixed solution, close the lid of the weighing bottle, and place the lid and the weighing bottle between the A 0.5cm wide filter paper strip is placed between the bottles (the filter paper strip is used to leave some gaps to allow the aromatic organic solvent B to volatilize), and place it in the aromatic polyaldehyde mixed solution at room temperature of 20-25°C After volatilization of the aromatic organic solvent B (the standing time is 24 hours), a two-dimensional polymer film with a thickness of 20 nm is obtained on the liquid surface, wherein,

The ratio of the amount of the aromatic polyaldehyde in the aromatic polyaldehyde mixed solution to the aromatic polyamine in the aromatic polyamine mixed solution is 0.00167:0.01389;

The configuration method of the aromatic polyamine mixed solution is: uniformly distributing the aromatic polyamine in the organic solvent A to obtain a solution A, adding deionized water to the solution A and mixing uniformly to obtain a light brown aromatic polyamine mixed solution, wherein, The ratio of the volume fraction of deionized water to the substance fraction of aromatic polyamine was 1:0.01389. The concentration of aromatic polyamine in solution A is 1.2 mmol/mL, the organic solvent A is an aprotic and water-miscible organic reagent, and the organic solvent A is N,N-dimethylformamide.

The configuration method of the aromatic polyaldehyde mixed solution is: uniformly distributing the aromatic polyaldehyde in the aromatic organic solvent B to obtain a solution B, adding an organic acid to the solution B to obtain an aromatic polyaldehyde mixed solution, wherein the aromatic organic solvent B The ratio of the volume fraction of the aromatic polyaldehyde to the material fraction of the aromatic polyaldehyde is 1:0.00167, and the volume of the organic acid is 1% of the volume of the solution B;

The organic acid is acetic acid;

The aromatic organic solvent B is chlorobenzene.

The aromatic polyaldehyde is trimesicaldehyde.

The aromatic polyamine is p-phenylenediamine.

Example 2

A preparation method of a two-dimensional polymer film, comprising the following steps:

Arrange the aromatic polyamine mixed solution in a weighing bottle with a diameter of 7cm, add the aromatic polyaldehyde mixed solution dropwise to the liquid surface of the aromatic polyamine mixed solution, close the lid of the weighing bottle, and place the lid and the weighing bottle between the A 0.5cm wide filter paper strip is placed between the bottles, and placed at room temperature of 20-25°C until the aromatic organic solvent B in the aromatic polyaldehyde mixed solution has evaporated (the placement time is 36 hours). A two-dimensional polymer film with a thickness of 50 nm was obtained, wherein,

The ratio of the amount of the aromatic polyaldehyde in the aromatic polyaldehyde mixed solution to the aromatic polyamine in the aromatic polyamine mixed solution is 0.00333:0.01389;

The configuration method of the aromatic polyamine mixed solution is: uniformly distributing the aromatic polyamine in the organic solvent A to obtain a solution A, adding deionized water to the solution A and mixing uniformly to obtain a light brown aromatic polyamine mixed solution, wherein, The ratio of the volume fraction of deionized water to the substance fraction of aromatic polyamine was 1:0.01389. The concentration of aromatic polyamine in solution A is 1.2 mmol/mL, the organic solvent A is an aprotic and water-miscible organic reagent, and the organic solvent A is N,N-dimethylformamide.

The configuration method of the aromatic polyaldehyde mixed solution is: uniformly distributing the aromatic polyaldehyde in the aromatic organic solvent B to obtain a solution B, adding an organic acid to the solution B to obtain an aromatic polyaldehyde mixed solution, wherein the aromatic organic solvent B The ratio of the volume fraction of the aromatic polyaldehyde to the material fraction of the aromatic polyaldehyde is 1:0.00333, and the volume of the organic acid is 1% of the volume of the solution B;

The organic acid is acetic acid;

The aromatic organic solvent B is chlorobenzene.

The aromatic polyaldehyde is trimesicaldehyde.

The aromatic polyamine is p-phenylenediamine.

Example 3

A preparation method of a two-dimensional polymer film, comprising the following steps:

Arrange the aromatic polyamine mixed solution in a weighing bottle with a diameter of 7cm, add the aromatic polyaldehyde mixed solution dropwise to the liquid surface of the aromatic polyamine mixed solution, close the lid of the weighing bottle, and place the lid and the weighing bottle between the A 0.5cm wide filter paper strip is sandwiched between the bottles, and placed at room temperature of 20-25°C until the aromatic organic solvent B in the aromatic polyaldehyde mixed solution has evaporated (the placement time is 48 hours), and the A two-dimensional polymer film with a thickness of 70 nm was obtained, wherein,

The ratio of the amount of the aromatic polyaldehyde in the aromatic polyaldehyde mixed solution to the aromatic polyamine in the aromatic polyamine mixed solution is 0.005:0.01389;

The configuration method of the aromatic polyamine mixed solution is: uniformly distributing the aromatic polyamine in the organic solvent A to obtain a solution A, adding deionized water to the solution A and mixing uniformly to obtain a light brown aromatic polyamine mixed solution, wherein, The ratio of the volume fraction of deionized water to the substance fraction of aromatic polyamine was 1:0.01389. The concentration of aromatic polyamine in solution A is 1.2 mmol/mL, the organic solvent A is an aprotic and water-miscible organic reagent, and the organic solvent A is N,N-dimethylformamide.

The configuration method of the aromatic polyaldehyde mixed solution is: uniformly distributing the aromatic polyaldehyde in the aromatic organic solvent B to obtain a solution B, adding an organic acid to the solution B to obtain an aromatic polyaldehyde mixed solution, wherein the aromatic organic solvent B The ratio of the volume fraction of B to the aromatic polyaldehyde substance is 1:0.005, and the volume of the organic acid is 1% of the volume of the solution B;

The organic acid is acetic acid;

The aromatic organic solvent B is chlorobenzene.

The aromatic polyaldehyde is trimesicaldehyde.

The aromatic polyamine is p-phenylenediamine.

Figure 2 is the AFM characterization of the two-dimensional polymer films prepared in Examples 1-3, wherein, 2(a) is the two-dimensional polymer film prepared in Example 1, with a thickness of 20 nm; 2(b) It is the two-dimensional polymer film prepared in Example 2, with a thickness of 50 nm; 2(c) is the two-dimensional polymer film prepared in Example 3, with a thickness of 70 nm; it can be seen from the figure that the two-dimensional polymer film prepared by the present invention is The film has good uniformity, and the roughness within 10um is 0.2nm (Example 1), 0.7nm (Example 2) and 1.8nm (Example 3), respectively, and the roughness is low.

After soaking the obtained two-dimensional polymer films (2DP) prepared in Examples 1-3 with DMF, dichloromethane, chloroform and acetone for 5 hours respectively, it was found that the 2DP material still existed stably.

Example 4

The two-dimensional polymer film prepared in Example 1 was used as the active layer to obtain a memristor. The memristor from top to bottom was an active electrode, a two-dimensional polymer film and an inert electrode, as shown in Figure 1. The active electrode is a silver layer with a thickness of 50 nm; the inert electrode is an ITO conductive glass layer. The preparation method of the memristor includes the following steps:

a) Transfer the two-dimensional polymer film to the upper surface of the inert electrode, and vacuum dry it in a vacuum drying oven at 30 °C for 8 h;

的速率沉积厚度为50nm的银层，沉积结束后取下铜网，完成蒸镀银层。b) Evaporation of active electrodes on 2D polymer films. The method of evaporating the silver layer is as follows: use a 100/400 copper mesh as a mask to stick on the upper surface of the two-dimensional polymer film (the mesh number of the copper mesh is 200 meshes), and

A silver layer with a thickness of 50 nm was deposited at a rate of 100 Å, and the copper mesh was removed after the deposition to complete the evaporation of the silver layer.

Figure 3 shows the opening and erasing curves of the memristor obtained in Example 4 (using a two-dimensional polymer film with a thickness of 20 nm); when testing the device, the ITO (ITO conductive glass layer) was grounded, and the Ag electrode (silver layer) Apply a voltage on 0.02V steps. In Fig. 3, 1 refers to the curve of scanning process from 0V-1.5V, 2 refers to the curve scanned from 1.5-0V, the limit current of curves 1 and 2 is ^10-3 during testing; 3 refers to Curves appearing from a 0-3.3V sweep, 4 refers to curves appearing from a 3.3-0V sweep, and curves 3 and 4 have a limited current of 10 ^-2 . Curves 1 and 2 are the writing process of the memristor, which is equivalent to the step of information storage, and curves 3 and 4 are the erasing process of the memristor. It can be seen from FIG. 3 that the memristor prepared from the two-dimensional polymer film obtained in Example 1 can perform a complete writing and erasing process.

Fig. 4 is the statistics of the cycle stability of the memristor obtained in Example 4. When the same device (memristor) was repeatedly turned on and erased, it was found that a two-dimensional polymer film of this thickness was used as a device with an active layer. 100 normal operations can be performed.

Figure 5 is the statistics of the high and low resistance states of the memristor obtained in Example 4; the opening and erasing operations were performed on the memristor prepared from the same batch of 20nm thick two-dimensional polymer films, and 200 devices were counted in - The value of the high and low resistance states at 0.1V can be seen from Figure 5. It is found that the switching ratio of the memristor prepared by the 20nm thick two-dimensional polymer film is in the order of 10 ² .

Figure 6 shows the retention time of the memristor obtained by reading the memristor obtained in Example 4 with a 0.1V voltage; after the device is written to, the device is read with a 0.1V voltage to obtain the retention time of the device in a low resistance state; After the same device is erased, the device is read with a voltage of 0.1V to obtain the retention time of the device in a high resistance state. The obtained two retention time curves are plotted in the same graph, and it is found that the read time of the device under this thickness is 8*10 ³ s under 0.1V voltage.

Example 5

The two-dimensional polymer film prepared in Example 2 was used as the active layer to obtain a memristor. The memristor from top to bottom was: an active electrode, a two-dimensional polymer film and an inert electrode. The active electrode was a silver layer with a thickness of 50nm; the inert electrode is an ITO conductive glass layer. The preparation method of the memristor includes the following steps:

a) Transfer the two-dimensional polymer film to the upper surface of the inert electrode, and vacuum dry it in a vacuum drying oven at 30 °C for 8 h;

的速率沉积厚度为50nm的银层，沉积结束后取下铜网，完成蒸镀银层。b) Evaporation of active electrodes on 2D polymer films. The method of evaporating the silver layer is as follows: use a 100/400 copper mesh as a mask to stick on the upper surface of the two-dimensional polymer film (the mesh number of the copper mesh is 200 meshes), and

A silver layer with a thickness of 50 nm was deposited at a rate of 100 Å, and the copper mesh was removed after the deposition to complete the evaporation of the silver layer.

Figure 7 is the turn-on and erasing curves of the memristor obtained in Example 5; when testing the device, ITO was grounded, and a voltage was applied on the Ag electrode with a step size of 0.02V. In Fig. 7, 1 refers to the curve of scanning process from 0V-1.5V, 2 refers to the curve scanned from 1.5-0V, and the limit current of curves 1 and 2 is ^10-3 during testing; 3 refers to Curves appearing from a 0-3.3V sweep, 4 refers to curves appearing from a 3.3-0V sweep, and curves 3 and 4 have a limited current of 10 ^-2 . Curves 1 and 2 are the writing process of the memristor, which is equivalent to the step of information storage, and curves 3 and 4 are the erasing process of the memristor. It can be seen from the figure that the memristor prepared with a 50 nm thick two-dimensional polymer film can perform a complete writing and erasing process.

FIG. 8 is the statistics of the cycle stability of the memristor obtained in Example 5. The cycle stability test was performed on the memristor prepared from a 50 nm thick two-dimensional polymer film. After repeated opening and erasing operations on the same device, it was found that the device with a two-dimensional polymer film of this thickness as the active layer could perform 180 normal operations.

Figure 9 is the statistics of the high and low resistance states of the memristor obtained in Example 5 (using a 50 nm thick two-dimensional polymer film); the memristors prepared from the same batch of 50 nm thick two-dimensional polymer films were turned on and Erase operation and count the high and low resistance state values of 200 devices at -0.1V, as shown in Figure 9. It is found that the switching ratio of the memristor made of 50nm thick two-dimensional polymer is in the order of 10 ⁴ .

Figure 10 shows the retention time of the memristor obtained in Example 5 by reading the 0.1V voltage (using a two-dimensional polymer film with a thickness of 50 nm); it can be seen from the figure that after the device is written, the device is Reading is performed to obtain the retention time of the device in the low resistance state; after the same device is erased, the device is read with a voltage of 0.1V to obtain the retention time of the device in the high resistance state. The obtained two retention time curves are plotted in the same graph, and it is found that the read time of the device under this thickness is 1*10 ⁴ s under the voltage of 0.1V.

Example 6

The two-dimensional polymer film prepared in Example 3 was used as the active layer to obtain a memristor. The memristor from top to bottom was: an active electrode, a two-dimensional polymer film and an inert electrode. The active electrode was a silver layer with a thickness of 50nm; the inert electrode is an ITO conductive glass layer. The preparation method of the memristor includes the following steps:

a) Transfer the two-dimensional polymer film to the upper surface of the inert electrode, and vacuum dry it in a vacuum drying oven at 30 °C for 8 h;

的速率沉积厚度为50nm的银层，沉积结束后取下铜网，完成蒸镀银层。b) Evaporation of active electrodes on 2D polymer films. The method of evaporating the silver layer is as follows: use a 100/400 copper mesh as a mask to stick on the upper surface of the two-dimensional polymer film (the mesh number of the copper mesh is 200 meshes), and

A silver layer with a thickness of 50 nm was deposited at a rate of 100 Å, and the copper mesh was removed after the deposition to complete the evaporation of the silver layer.

Figure 11 shows the turn-on and erase curves of the memristor obtained in Example 6 (using a two-dimensional polymer film with a thickness of 70 nm); when testing the device, ITO was grounded, and a voltage was applied to the Ag electrode with a step size of 0.02V. In Fig. 11, 1 refers to the curve of the scanning process from 0V-1.5V, 2 refers to the curve scanned from 1.5-0V, and the limit current of the curves 1 and 2 is ^10-3 during testing; 3 refers to Curves appearing from a 0-3.3V sweep, 4 refers to curves appearing from a 3.3-0V sweep, and curves 3 and 4 have a limited current of 10 ^-2 . Curves 1 and 2 are the writing process of the memristor, which is equivalent to the step of information storage, and curves 3 and 4 are the erasing process of the memristor. It can be seen from the figure that the device made of 70nm thick two-dimensional polymer can perform the complete writing and erasing process.

Figure 12 shows the statistics of the cycle stability of the memristor obtained in Example 6 (using a two-dimensional polymer film with a thickness of 70 nm); the cycle stability test was performed on the memristor prepared with a two-dimensional polymer film with a thickness of 70 nm. After repeatedly turning on and erasing the same device, it was found that the device with this thickness of two-dimensional polymer as the active layer can perform 200 normal operations.

Figure 13 is the statistics of the high and low resistance states of the memristor obtained in Example 6 (using a 70 nm thick two-dimensional polymer film); the memristors prepared from the same batch of 70 nm thick two-dimensional polymer films were turned on and erased Divide the operation, and count the high and low resistance state values of 200 devices at -0.1V, plotted as Figure 13, it is found that the switching ratio of the memristor prepared by the 70nm thick two-dimensional polymer film is in the order of 10 ⁵ .

Figure 14 shows the retention time of the memristor obtained in Example 6 with 0.1V reading (using a two-dimensional polymer film with a thickness of 70 nm). After the device is written, the device is read with 0.1V. The retention time of the device in the low resistance state is obtained; after the same device is erased, the device is read with a voltage of 0.1V to obtain the retention time of the device in the high resistance state. The obtained two retention time curves are plotted in the same graph, and it is found that the reading time of the device under this thickness is 3.5*10 ⁴ s under the voltage of 0.1V.

FIG. 15 is the nitrogen adsorption/desorption curve of the two-dimensional polymer film prepared in Example 2. FIG. It can be seen from the figure that the curve belongs to the type I absorption curve, but the desorption curve does not coincide with the adsorption curve, indicating that a part of nitrogen is fixed in 2DP _BTA+PDA , which proves that there are micropores in the material. The calculated specific surface area of the material is 74.4 m ² /g, and the pore volume is 8.82×10 ^-2 cm ³ /g. Using the data in Figure 15, the pore size of the 2DP _BTA+PDA (two-dimensional polymer film) is calculated to be 1.41 nm through delocalized density function theory, as shown in Figure 16. (The model of the instrument used in Figures 15 and 16: JB-2020 specific surface area tester)

Fig. 17 is the Fourier transform infrared spectrum of the two-dimensional polymer film obtained by Example 2, 3392cm ^-1 is the NH bond stretching vibration, 2292cm ^-1 is the stretching vibration of -NH _on the unreacted aromatic polyamine monomer, 1694cm ^-1 is the stretching vibration of C=O reacting on the BTA molecule of aromatic polyaldehyde, 1621cm ^-1 is the stretching vibration of C=N generated by the reaction of aromatic polyaldehyde and aromatic polyamine by Schiff base, 1260cm ^-1 is Stretching vibration of the C-N bond between the benzene ring and the nitrogen atom. The appearance of the characteristic peak 1621 indicates that the aromatic polyaldehyde and aromatic polyamine indeed undergo Schiff base reaction under the catalysis of organic acid, and the generated 2DP is formed by the polymerization of two monomers under the reaction (response) of Schiff base of. (Model of instrument used: Bruker VERTEX80/80v.)

It can be seen from FIG. 18 that the two-dimensional polymer film is a material with an amorphous structure. It can be seen from FIG. 19 that the image exhibits the phenomenon of diffraction rings, indicating that the material is in an amorphous state, which verifies the results in FIG. 18 . (Instrument used: Hitachi HT7800)

In the technical solution of the present invention, N,N-dimethylformamide is changed to N,N-dimethylacetamide or dimethyl sulfoxide, or acetic acid is changed to trifluoroacetic acid or trifluoromethanesulfonic acid , or change chlorobenzene into dichlorobenzene or toluene, and its technical effect is consistent with the above-mentioned embodiment.

The present invention has been exemplarily described above. It should be noted that, without departing from the core of the present invention, any simple deformations, modifications or other equivalent replacements that those skilled in the art can do without creative effort fall into the scope of the present invention. the scope of protection of the invention.

Claims (10)

1. the memristor that a two-dimensional polymer film obtains as an active layer, is characterized in that, the preparation method of described two-dimensional polymer film may further comprise the steps: Add the aromatic polyaldehyde mixed solution dropwise to the liquid surface of the aromatic polyamine mixed solution, place it at room temperature 20-25° C. until the aromatic organic solvent B in the aromatic polyaldehyde mixed solution is volatilized, and obtain on the liquid surface Two-dimensional polymer films, where, The ratio of the amount of the aromatic polyaldehyde in the aromatic polyaldehyde mixed solution to the amount of the aromatic polyamine in the aromatic polyamine mixed solution (0.0015~0.005): 0.01389; The configuration method of the aromatic polyamine mixed solution is as follows: evenly distributing the aromatic polyamine in the organic solvent A to obtain a solution A, adding deionized water to the solution A and uniformly mixing to obtain a light brown aromatic polyamine mixed solution solution, wherein, the concentration of aromatic polyamine in the solution A is 0.185～4.63 mmol/mL, and the organic solvent A is an aprotic and water-miscible organic reagent; The configuration method of the aromatic polyaldehyde mixed solution is as follows: evenly distributing the aromatic polyaldehyde in the aromatic organic solvent B to obtain a solution B, adding an organic acid to the solution B to obtain an aromatic polyaldehyde mixed solution, wherein the The ratio of the volume fraction of the aromatic organic solvent B to the material fraction of the aromatic polyaldehyde is (0.5~1): (0.0008~0.01), and the volume of the organic acid is the volume of the solution B 0.7~1.5% of ; The organic acid is acetic acid, trifluoroacetic acid or trifluoromethanesulfonic acid; Aromatic organic solvent B is chlorobenzene, dichlorobenzene or toluene; The aromatic polyaldehyde is trimesaldehyde; the aromatic polyamine is p-phenylenediamine. 2 . The memristor according to claim 1 , wherein the memristor is, from top to bottom, an active electrode, a two-dimensional polymer film, and an inert electrode, and the active electrode is an aluminum layer, a copper layer, and an inert electrode. 3 . layer or silver layer; the inert electrode is an ITO conductive glass layer, a gold layer or a platinum layer. 3 . The memristor according to claim 2 , wherein the time for the aromatic organic solvent B to evaporate is at least 24 hours. 4 . 4 . The memristor according to claim 3 , wherein, in the aromatic polyamine mixed solution, the ratio of the volume fraction of the deionized water to the material fraction of the aromatic polyamine is 1: (0.005~0.03); the unit of said volume fraction is mL, and the unit of said substance fraction is mmol. 5. The memristor according to claim 4, wherein the deionized water is ultrapure water, and the resistivity is 18.2MΩ﹒ cm. 6 . The memristor according to claim 5 , wherein the organic solvent A is N,N-dimethylformamide, N,N-dimethylacetamide or dimethylsulfoxide. 7 . 7 . The memristor according to claim 6 , wherein the thickness of the active electrode is 10-200 nm; the thickness of the two-dimensional polymer film is 2-80 nm. 8 . 8. The preparation method of the memristor according to any one of claims 1 to 7, wherein the method comprises the following steps: a) Transfer the two-dimensional polymer film to the upper surface of the inert electrode, and vacuum dry it in a vacuum drying oven at 15-40 °C for 2-10 h; b) Evaporating the active electrode on the two-dimensional polymer film. 9 . The method for preparing a memristor according to claim 8 , wherein in the step b), when the active electrode is a silver layer, the method for evaporating the silver layer is: using copper The mesh is attached to the upper surface of the two-dimensional polymer film as a mask, and a silver layer with a thickness of 20-100 nm is deposited at a rate of 0.05-2 Å. After the deposition, the copper mesh is removed to complete the evaporation of the silver layer. . 10 . The method for preparing a memristor according to claim 9 , wherein the mesh number of the copper mesh is 200-300 meshes. 11 .

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