Preparation method of biological ovalbumin film memristor film

Abstract

The invention discloses a preparation method of a biological ovalbumin film memristor film. The preparation method comprises the following steps: step 1, weighing egg white; step 2, adding deionized water into egg white, and fully stirring to obtain ovalbumin sol; the volume ratio of the deionized water to the egg white is (0.5-1): 1; 3, the titanium carbide MXene nanosheet with the concentration being 5 mg / ml is dispersed in deionized water, and a titanium carbide MXene nanosheet solution with the concentration being 0.005 mg / ml is obtained; step 4, mixing the ovalbumin sol and the titanium carbide MXene nanosheet solution according to a volume ratio of 1: 1, and fully stirring to obtain ovalbumin sol regulated and controlled by an MXene nanosheet layer; and 5, preparing the biological ovalbumin film memristor film by using the ovalbumin sol regulated and controlled by the MXene nanosheet layer as a raw material by adopting a dip-coating method. According to the preparation method of the biological ovalbumin film memristor film, the problem that a biological film memristor memory film is unstable is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of memristor film material preparation, and in particular relates to a method for preparing a biological ovalbumin film memristor film. Background Art

[0002] Bioresistive film is a special film material that combines the characteristics of biomaterials with resistive properties, and shows great application potential in the fields of biomedicine, electronics and materials science. The resistance change process of bioresistive film involves a variety of physical and chemical mechanisms, including but not limited to charge trap effect, ion migration effect and redox reaction. Under the action of these mechanisms, the film can undergo significant changes in resistance under the stimulation of external current and voltage. The charge trap effect means that there may be some charge traps inside the film, which can capture and release charges. When an external electric field acts, the charge traps capture charges, causing the resistance of the film to change. The ion migration effect means that in some films, ions (such as oxygen ions, metal ions, etc.) will migrate under the action of an electric field. The migration of ions will change the charge distribution and chemical state inside the film, thereby affecting its resistance value. Redox reaction means that the external electric field may trigger redox reactions inside the film, which will change the chemical composition and charge state of the film, thereby affecting its resistance value. However, no matter which resistance change mechanism is used, when the resistance value of the film changes, its internal energy distribution and heat flow will also be affected. Especially at the moment of resistance change, due to the rapid movement and redistribution of charges, local thermal effects will occur, thus affecting the rate and stability of resistance change. Nanosheet MXene has excellent thermal conductivity. The thermal conductivity of single-layer or few-layer MXene films ranges from 1.26 W·m -1 Increased to 2.84W·m -1(Increased from 80K to 290K). This characteristic makes MXene materials have great application potential in the field of thermal conduction. The present invention uses MXene nanosheets to regulate in the process of preparing ovalbumin memristor film. By adjusting the concentration of added MXene nanosheets, the thermal effect of the protein film can be effectively improved, and the resistive switching performance of the ovalbumin film can be further improved. Egg whites in eggs are used. The main component of egg whites is water-soluble ovalbumin, which is also the most abundant protein in egg whites, accounting for about 54% of the total protein in egg whites. The advantage of natural biomaterials is that they are environmentally friendly and reduce the manufacturing cost of organic storage devices. So far, protein memristor materials from various sources have emerged, such as silk fibroin, ferritin, egg albumin, recombinant protein, keratin, etc., which have been proven to have typical resistive switching performance and can be applied to the research and development of data storage electronic devices. The thermal conduction of resistive biofilms during resistance transformation is a complex and interesting research field. By using the nanosheet MXene regulation method to deeply understand its mechanism and application prospects, it can provide a theoretical basis and technical support for the development of new bioelectronic devices and sensors. Summary of the invention

[0003] The purpose of the present invention is to provide a method for preparing a biological ovalbumin film memristor thin film, so as to solve the problem of instability of the biological thin film memristor memory film.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is: a method for preparing a biological ovalbumin film memristor thin film, which is specifically implemented according to the following steps: Step 1, weighing egg white; Step 2, adding deionized water to the egg white and stirring thoroughly to obtain an egg white protein sol; the volume ratio of the deionized water to the egg white is (0.5-1):1; Step 3, dispersing titanium carbide MXene nanosheets with a concentration of 5 mg / ml in deionized water to obtain a titanium carbide MXene nanosheet solution with a concentration of 0.005 mg / ml; Step 4, mixing the ovalbumin sol and the titanium carbide MXene nanosheet solution in a volume ratio of 1:1, and stirring thoroughly to obtain the ovalbumin sol regulated by the MXene nanosheet layer; Step 5, preparing a biological ovalbumin film memristor film using an immersion pulling method and an ovalbumin sol regulated by MXene nanosheets as a raw material.

[0005] As a preferred technical solution of the present invention, in step 1, the shells of fresh eggs are washed and dried, the eggshells are broken and the egg white and egg yolk are separated, and the egg white is placed in a beaker for centrifugation and filtration to obtain the egg white required for step 1.

[0006] As a preferred technical solution of the present invention, in step 2, sufficient stirring is carried out at 20°C - 25°C.

[0007] As a preferred technical solution of the present invention, in step 2, the time for sufficient stirring is 5 min-8 min.

[0008] As a preferred technical solution of the present invention, in step 4, sufficient stirring is carried out at 20°C - 25°C.

[0009] As a preferred technical solution of the present invention, in step 4, the time for sufficient stirring is 25 min-30 min.

[0010] As a preferred technical solution of the present invention, in step 5, an immersion pulling method is adopted. At room temperature, a pulling machine is used to clamp a corner of a single-crystalline silicon substrate with a bottom electrode (ITO) with a fish-mouth clamp, and the film pulling equipment switch is turned on to pull the film in the ovalbumin sol regulated by the MXene nanosheet layer at a speed of 18 mm / s. The ovalbumin film regulated by the MXene nanosheet layer obtained by pulling is dried at room temperature for 5 minutes to obtain a biological ovalbumin memristor film.

[0011] As a preferred technical solution of the present invention, the normal temperature is 25°C.

[0012] The beneficial effects of the present invention are as follows: the raw material used in the preparation method of the biological ovalbumin film memristor film of the present invention is eggs, wherein the main component of egg white is water-soluble ovalbumin, which is also the most abundant protein in egg white, accounting for about 54% of the total protein in egg white. The advantage of natural biological materials is that they are environmentally friendly and reduce the manufacturing cost of organic memory devices. At the same time, the ovalbumin memristor film with stable resistive switching performance can be obtained by using the MXene nanosheet control method with simple process and controllable operation flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings: Figure 1 This is a Fourier transform infrared spectrum of the biological ovalbumin film prepared in Example 5 of the present invention.

[0014] Figure 2 This is a scanning probe microscope image of the biological ovalbumin film prepared in Example 5 of the present invention.

[0015] Figure 3This is a test diagram of the resistive switching performance of the biological ovalbumin memristor in Example 5 of the present invention.

[0016] Figure 4 This is a scanning probe microscope image of the MXene nanosheet layer in Example 6 of the present invention.

[0017] Figure 5 This is a scanning probe microscope image of the biological ovalbumin film formed after being regulated by the MXene nanosheet layer in Example 6 of the present invention.

[0018] Figure 6 This is a test diagram of the resistive switching performance of the biological ovalbumin memristor after being regulated by the MXene nanosheet layer in Example 6 of the present invention.

[0019] Figure 7 This is a test diagram of the thermal conductivity of the device in Example 6 of the present invention. DETAILED DESCRIPTION

[0020] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0021] Example 1 The method for preparing a biological ovalbumin film memristor thin film of the present invention is specifically implemented according to the following steps: Step 1, wash and dry the shells of fresh eggs, break the eggshells and separate the egg white and egg yolk, and place the egg white in a beaker for centrifugation and filtration; Step 2, using a pipette to draw 1 ml of egg white liquid and drip it into a weighing bottle, then using a dropper to draw 0.8 ml of deionized water and drip it into the weighing bottle, mixing and stirring at 23° C. for 5 min-8 min to obtain an egg white protein sol; Step 3, dispersing titanium carbide MXene nanosheets with a concentration of 5 mg / ml in deionized water to obtain a titanium carbide MXene nanosheet solution with a concentration of 0.005 mg / ml; Step 4, mixing the ovalbumin sol and the titanium carbide MXene nanosheet solution in a volume ratio of 1:1, and stirring the mixture at 23° C. for 29 minutes to obtain the ovalbumin sol regulated by the MXene nanosheet layer; Step 5, using the immersion pulling method, at room temperature, use a pulling machine to clamp a corner of the single-crystalline silicon substrate with a bottom electrode (ITO) with a fish-mouth clamp, turn on the film pulling equipment switch, and pull it in the ovalbumin sol regulated by the MXene nanosheet layer at a speed of 18 mm / s. Dry the ovalbumin film regulated by the MXene nanosheet layer obtained by pulling at room temperature 25°C for 5 minutes to obtain a biological ovalbumin memristor film.

[0022] Example 2 The method for preparing a biological ovalbumin film memristor thin film of the present invention is specifically implemented according to the following steps: Step 1, wash and dry the shells of fresh eggs, break the eggshells and separate the egg white and egg yolk, and place the egg white in a beaker for centrifugation and filtration; Step 2, using a pipette to draw 1 ml of egg white solution and drip it into a weighing bottle, then using a dropper to draw 0.6 ml of deionized water and drip it into the weighing bottle, mixing and stirring at 22° C. for 7 minutes to obtain an egg white protein sol; Step 3, dispersing titanium carbide MXene nanosheets with a concentration of 5 mg / ml in deionized water to obtain a titanium carbide MXene nanosheet solution with a concentration of 0.005 mg / ml; Step 4, mixing the ovalbumin sol and the titanium carbide MXene nanosheet solution in a volume ratio of 1:1, and stirring the mixture at 22° C. for 26 minutes to obtain the ovalbumin sol regulated by the MXene nanosheet layer; Step 5, using the immersion pulling method, at room temperature, use a pulling machine to clamp a corner of the single-crystalline silicon substrate with a bottom electrode (ITO) with a fish-mouth clamp, turn on the film pulling equipment switch, and pull it in the ovalbumin sol regulated by the MXene nanosheet layer at a speed of 18 mm / s. Dry the ovalbumin film regulated by the MXene nanosheet layer obtained by pulling at room temperature 25°C for 5 minutes to obtain a biological ovalbumin memristor film. Example 3 The method for preparing a biological ovalbumin film memristor thin film of the present invention is specifically implemented according to the following steps: Step 1, wash and dry the shells of fresh eggs, break the eggshells and separate the egg white and egg yolk, and place the egg white in a beaker for centrifugation and filtration; Step 2, using a pipette to draw 1 ml of egg white solution and drip it into a weighing bottle, then using a dropper to draw 0.5 ml of deionized water and drip it into the weighing bottle, mixing and stirring at 20° C. for 8 minutes to obtain an egg white protein sol; Step 3, dispersing titanium carbide MXene nanosheets with a concentration of 5 mg / ml in deionized water to obtain a titanium carbide MXene nanosheet solution with a concentration of 0.005 mg / ml; Step 4, mixing the ovalbumin sol and the titanium carbide MXene nanosheet solution in a volume ratio of 1:1, and stirring the mixture at 20° C. for 30 minutes to obtain the ovalbumin sol regulated by the MXene nanosheet layer; Step 5, using the immersion pulling method, at room temperature, use a pulling machine to clamp a corner of the single-crystalline silicon substrate with a bottom electrode (ITO) with a fish-mouth clamp, turn on the film pulling equipment switch, and pull it in the ovalbumin sol regulated by the MXene nanosheet layer at a speed of 18 mm / s. Dry the ovalbumin film regulated by the MXene nanosheet layer obtained by pulling at room temperature 25°C for 5 minutes to obtain a biological ovalbumin memristor film.

[0023] Example 4 The method for preparing a biological ovalbumin film memristor thin film of the present invention is specifically implemented according to the following steps: Step 1, wash and dry the shells of fresh eggs, break the eggshells and separate the egg white and egg yolk, and place the egg white in a beaker for centrifugation and filtration; Step 2, using a pipette to draw 1 ml of egg white liquid and drip it into a weighing bottle, then using a dropper to draw 1 ml of deionized water and drip it into the weighing bottle, mixing and stirring at 25° C. for 5 minutes to obtain an egg white protein sol; Step 3, dispersing titanium carbide MXene nanosheets with a concentration of 5 mg / ml in deionized water to obtain a titanium carbide MXene nanosheet solution with a concentration of 0.005 mg / ml; Step 4, mixing the ovalbumin sol and the titanium carbide MXene nanosheet solution in a volume ratio of 1:1, and stirring the mixture at 25° C. for 25 minutes to obtain the ovalbumin sol regulated by the MXene nanosheet layer; Step 5, using the immersion pulling method, at room temperature, use a pulling machine to clamp a corner of the single-crystalline silicon substrate with a bottom electrode (ITO) with a fish-mouth clamp, turn on the film pulling equipment switch, and pull it in the ovalbumin sol regulated by the MXene nanosheet layer at a speed of 18 mm / s. Dry the ovalbumin film regulated by the MXene nanosheet layer obtained by pulling at room temperature 25°C for 5 minutes to obtain a biological ovalbumin memristor film.

[0024] Example 5 Example 5 is a comparative example of the preparation method of a biological egg white protein film memristor film of the present invention, specifically: wash and dry the shell of a fresh egg, break the egg shell and separate the egg white and egg yolk, put the egg white in a beaker for centrifugation and filtration. Use a pipette to draw 1 ml of egg white liquid and drop it into a weighing bottle, then use a dropper to draw 1 ml of deionized water and drop it into the weighing bottle, mix and stir at 25°C for 5 minutes to obtain an egg white protein sol, which is ready for use. Figure 1 The following is a Fourier transform infrared spectrum picture. The characteristic peak of ovalbumin is mainly at 1391 cm -1The absorption peaks appearing at 1600-1700 cm-1 represent the cis-configuration and trans-configuration absorption peaks of the peptide bond group -HN-C=O. The amide I band appears at 1600-1700 cm-1. -1 Based on the peak shape and position in this area, we can judge the α-helix, β-sheet, and β-turn in ovalbumin. The stretching vibration absorption peak of the NH bond appears at 3396.4 cm -1 .

[0025] Using the pulling method, at room temperature, use a pulling machine to clamp a corner of the single-crystal silicon substrate with a bottom electrode (ITO) with a fish-mouth clamp, turn on the film pulling device switch, and pull it in the egg white protein sol at a speed of 10mm / s. The egg white protein film obtained by pulling is dried at room temperature 25℃ for 5 minutes to obtain an egg white protein memristor film. The biological egg white protein memristor film is tested by scanning probe microscopy. Figure 2 The following is a scanning probe microscope microscopic image. The measurement area is 5×5 μm 2 The surface roughness fluctuation value is 16.18nm. Egg egg white protein macromolecules with agglomerated particle size of about 500nm are evenly distributed on the surface. The surface of the egg white protein film is uniform and flat.

[0026] The method for preparing the device using the thin film of this embodiment is as follows: turn on the sputtering instrument, put the biological ovalbumin memristor thin film sample into the fixture and fix it, fix the mask plate, use the ion sputtering instrument to sputter the Pt top electrode on the substrate, the sputtering time is 150 s, the sputtering current is 5.5 mA, and the vacuum degree in the sputtering chamber is 8×10 -2 mbar, the sputtered Pt period is 1mm, and the top electrode of the dot matrix is ​​the top electrode of the biological ovalbumin memristor thin film memristor memory. A complete single crystal silicon / ITO / egg bulk / Pt biological ovalbumin memristor thin film memristor unit is prepared.

[0027] The electrical performance test steps of the bio-memristor device unit are as follows: place the prepared memristor memory on a precision probe table connected to an ammeter and voltmeter, connect the top electrode of the device to the positive voltage input probe, and the bottom electrode to the negative input signal probe, open the test program, select the current-voltage (IV) test mode, set the protection current to 1 milliampere (mA), and click the start measurement button to test the voltammetric scan curve (IV curve). Figure 3 The current-voltage curve of the bio-memristor Si / Pt / egg bulk / Au device is shown in the figure, which shows that the device is a bipolar memristor memory, and the reversal voltages in both the positive and negative directions are 2.3 V. The working curve of the device is stable, the high-resistance state conforms to the Poole-Frankfurt effect conduction mechanism, and the low-resistance state conforms to the ohmic conduction mechanism.

[0028] Example 6 Different from Example 5, Example 6 provides a method for preparing a biological ovalbumin film memristor thin film of the present invention, and the specific operations are as follows: Disperse titanium carbide MXene nanosheets with a concentration of 5 mg / ml in deionized water to obtain a titanium carbide MXene nanosheet solution with a concentration of 0.005 mg / ml. Apply the titanium carbide MXene nanosheet solution evenly on the surface of freshly cleaved high-order graphite and observe with a scanning probe microscope to ensure that the MXene nanosheet concentration is appropriate, such as Figure 3 As shown in the figure, MXene flakes are evenly distributed, with uniform size and moderate dispersion, without overlapping or stacking. Figure 3 The single-layer Mxene nanosheet in the upper left corner was observed in the micro-area, and its measured thickness (∆Z) is 3.22nm.

[0029] The titanium carbide MXene nanosheet solution with a concentration of 0.005 mg / ml and the ovalbumin sol were mixed in a volume ratio of 1:1, and the mixture was stirred at 25°C for 30 min to obtain the ovalbumin sol regulated by the MXene nanosheet layer. The immersion pulling method was adopted. At room temperature of 25°C, a pulling machine was used to clamp a corner of the single-crystal silicon substrate with a bottom electrode (ITO) with a fish mouth clamp, and the film pulling device switch was turned on to pull it in the ovalbumin sol at a speed of 18 mm / s. The ovalbumin film regulated by the MXene nanosheet layer obtained by pulling was dried at room temperature of 25°C for 5 minutes to obtain a biological ovalbumin memristor film. The biological memristor film was prepared by the ovalbumin film regulated by the MXene method. The film was observed by scanning probe microscopy, as shown in FIG. Figure 4 As shown, the measurement area is 5×5μm 2 The surface roughness fluctuation value is 26.21nm. The figure shows that the ovalbumin particles are evenly and densely arranged, the surface is flat, and the MXene nanosheets and ovalbumin are evenly fused, without obvious agglomeration and separation. This shows that the ovalbumin molecules regulated by 0.005mg / ml concentration of MXene nanosheets are more closely arranged.

[0030] A method for regulating a bio-memristor thin film device by using a MXene nanosheet layer in Example 6 is specifically performed as follows: turning on a sputtering instrument, placing an ovalbumin memristor thin film sample regulated by a MXene nanosheet layer into a fixture and fixing the mask plate, sputtering a Pt top electrode on the substrate using an ion sputtering instrument, the sputtering time is 150 s, the sputtering current is 5.5 mA, and the vacuum degree in the sputtering chamber is 8×10 -2mbar, the sputtered Pt period is 1mm, and the dot-matrix electrode is the top electrode of the memristor memory controlled by the MXene nanosheet layer. A complete Si / ITO / egg bulk: MXene / Pt biological ovalbumin memristor thin film memristor unit is prepared.

[0031] The electrical performance test steps of the bio-memristor device unit are as follows: place the prepared memristor memory on the precision probe table of the current and voltage meter, connect the top electrode of the device to the positive voltage input probe, and the bottom electrode to the negative input signal probe, open the test program, select the current-voltage (IV) test mode, set the protection current to 1 milliampere (mA), and click the start measurement button to test the voltammetric scan curve (IV curve). Figure 6 The current-voltage curve of the bio-memristor Si / Pt / eggyolk / Au device is shown, which shows that the device is a bipolar memristor memory, and the reversal voltages in both the positive and negative directions are 1.0V, which is significantly lower than the reversal voltage of the device in Example 5. The working curve of the device is stable, the high-resistance state conforms to the Poole-Frankfurt effect conduction mechanism, and the low-resistance state conforms to the ohmic conduction mechanism.

[0032] The thermal conductivity stability test of the bio-memristor device unit prepared in Example 6 was performed. The Si / ITO / egg bulk: MXene / Pt bio-ovalbumin memristor thin film memristor unit was placed on a 1cm×1cm graphite sheet, and the heating switch was turned on and set to 40 degrees Celsius. After reaching the temperature, it was kept warm for 10 minutes and then naturally cooled to room temperature. The electrical performance of the sample was then retested, and the steps were as follows: the prepared memristor memory was placed on the precision probe station of the ammeter and voltmeter, the top electrode of the device was connected to the positive voltage input probe, and the bottom electrode was connected to the negative input signal probe, the test program was opened, the current-voltage (IV) test mode was selected, the protection current was set to 1 milliampere (mA), and the start measurement button was clicked to test the voltammetric scan curve (IV curve). 16 measurements were performed in succession, and after recording the data, a high resistance (R on ) and low resistance (R off ) The measurement results are plotted in graphs, such as Figure 7 After 16 consecutive measurements, the high and low resistance values ​​of the device remained stable, indicating that heating at 40 degrees Celsius for 10 minutes did not destroy the resistive switching properties of ovalbumin, and it can still maintain stable resistance switching characteristics.

[0033] The above description shows and describes several preferred embodiments of the invention, but as mentioned above, it should be understood that the invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the invention concept described herein through the above teachings or the technology or knowledge of the relevant field. Changes and modifications made by those skilled in the art should be within the scope of protection of the claims attached to the invention without departing from the spirit and scope of the invention.

Claims

1. A method for preparing a biological ovalbumin film memristor thin film, characterized in that: Follow the steps below to implement it: Step 1, weighing egg white; Step 2, adding deionized water to the egg white and stirring thoroughly to obtain an egg white protein sol; the volume ratio of the deionized water to the egg white is (0.5-1):1; Step 3, dispersing titanium carbide MXene nanosheets with a concentration of 5 mg / ml in deionized water to obtain a titanium carbide MXene nanosheet solution with a concentration of 0.005 mg / ml; Step 4, mixing the ovalbumin sol and the titanium carbide MXene nanosheet solution in a volume ratio of 1:1, and stirring thoroughly to obtain the ovalbumin sol regulated by the MXene nanosheet layer; Step 5, preparing a biological ovalbumin film memristor film using an immersion pulling method and an ovalbumin sol regulated by MXene nanosheets as a raw material.

2. The method for preparing the biological ovalbumin film memristor thin film according to claim 1, characterized in that: In the step 1, the shell of a fresh egg is washed and dried, the egg shell is broken and the egg white and the egg yolk are separated, and the egg white is placed in a beaker for centrifugation and filtration to obtain the egg white required in step 1.

3. The method for preparing the biological ovalbumin film memristor thin film according to claim 2, characterized in that: In the step 2, sufficient stirring is performed at 20°C - 25°C.

4. The method for preparing the biological ovalbumin film memristor thin film according to claim 3, characterized in that: In step 2, the time for sufficient stirring is 5 min to 8 min.

5. The method for preparing the biological ovalbumin film memristor thin film according to claim 4, characterized in that: In step 4, sufficient stirring is performed at 20°C - 25°C.

6. The method for preparing the biological ovalbumin film memristor thin film according to claim 5, characterized in that: In step 4, the time for sufficient stirring is 25 min-30 min.

7. The method for preparing the biological ovalbumin film memristor thin film according to claim 6, characterized in that: In step 5, the immersion pulling method is adopted. At room temperature, a pulling machine is used to clamp a corner of a single-crystal silicon substrate with a bottom electrode (ITO) with a fish-mouth clamp, and the film pulling equipment switch is turned on to pull the film in the ovalbumin sol regulated by the MXene nanosheet layer at a speed of 18 mm / s. The ovalbumin film regulated by the MXene nanosheet layer obtained by pulling is dried at room temperature for 5 minutes to obtain a biological ovalbumin memristor film.

8. The method for preparing the biological ovalbumin film memristor thin film according to claim 7, characterized in that: The normal temperature is 25°C.

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