Memristor with biosynaptic structure and preparation method of memristor

Abstract

The invention provides a memristor with a biosynaptic structure and a preparation method of the memristor, and belongs to the technical field of memristors. The memristor simulating the biological synapse structure comprises two electrodes which are oppositely arranged; the crown ether doped two-dimensional material film layer is positioned between the electrodes; the polyelectrolyte hydrogel layer is positioned on the crown ether doped two-dimensional material film layer; wherein when voltage is applied to the electrode, the electrode on the polyelectrolyte hydrogel layer is subjected to oxidation reaction to generate metal transmission ions, the metal transmission ions reach the crown ether doped two-dimensional material film layer through the polyelectrolyte hydrogel layer, and the crown ether molecules in the crown ether doped two-dimensional material film layer are combined with the metal transmission ions, so that the crown ether molecules in the crown ether doped two-dimensional material film layer are separated from the metal transmission ions. Selective electrical response to the metal transmission ions is realized, so that the memristor presents a conductivity value related to the type of the metal transmission ions.

Description

Technical Field

[0001] The present invention belongs to the technical field of memristors, and in particular relates to a memristor with a biomimetic synapse structure and a preparation method thereof. Background Art

[0002] The separation of processors and memory in traditional electronic computer architectures has led to the von Neumann bottleneck, which means that the frequent data communication between processing units and storage units greatly reduces the processing speed and energy efficiency. The synaptic structure in the human brain integrates processing units and storage units based on ion conduction, which greatly reduces energy consumption while achieving efficient parallel processing of complex information. This has led people to focus on simulating biological synaptic structures to prepare high-performance synaptic components. A memristor is an electronic component whose resistance changes with time and voltage. The dynamic variable resistance and non-volatile conductivity of a memristor can achieve memory and learning functions similar to biological neural synapses, making it an ideal component for bionic synapses in brain-like computing.

[0003] Currently, memristors are usually electronic devices, but nature mostly relies on ions for energy-efficient information processing. Ions are selected by organisms as information carriers to generate and transmit signals. The types and chemical properties of ions are diverse, giving living systems more powerful encoding and parallel computing capabilities. Therefore, the development of memristors with multi-ion selectivity using ions as information carriers is crucial for future neuromorphic devices that realize low-energy, multi-data parallel encoding and computing.

[0004] There are many different strategies for designing ionic memristor structures. Here we focus on double-layer memristors, which are currently composed mainly of gel and membrane.

[0005] Double-layer gel structure memristor, heterogeneous structure to build PN junction to achieve high rectification ratio (currently reported up to 158.64, by doping porphyrin additives in hydrogel to change the charge characteristics of the gel to achieve high rectification ratio), with diode characteristics, build circuit to achieve logic gate function. Some double-layer hydrogel ion diode devices can achieve biological synaptic functions (such as EPSC), but their multi-ion selective response, retention time, sensitivity to different pulse voltages and energy consumption performance need to be further explored. Summary of the invention

[0006] In view of the above technical problems, the present invention provides a memristor with a biomimetic synaptic structure and a preparation method thereof, in order to at least partially solve the above technical problems. The specific technical solutions provided by the present invention are as follows.

[0007] As an embodiment of one aspect of the present invention, a memristor with a biomimetic synapse structure is provided, comprising: two electrodes disposed opposite to each other; and a crown ether-doped two-dimensional material film layer located between the electrodes and a polyelectrolyte hydrogel layer located on the crown ether-doped two-dimensional material film layer; Among them, when voltage is applied to the electrode, an oxidation reaction occurs at the electrode on the polyelectrolyte hydrogel layer to produce metal transport ions. The metal transport ions pass through the polyelectrolyte hydrogel layer to reach the crown ether-doped two-dimensional material film layer. Based on the binding effect between the crown ether molecules and the metal transport ions in the crown ether-doped two-dimensional material film layer, a selective electrical response to the metal transport ions is achieved, so that the memristor exhibits a conductivity value related to the type of metal transport ions.

[0008] As an embodiment of another aspect of the present invention, a method for preparing the above-mentioned memristor is provided, comprising: Adding crown ether molecules and two-dimensional materials into water, mixing them evenly and forming a film, thereby obtaining a crown ether-doped two-dimensional material film; Adding the gel material to the polyelectrolyte aqueous solution and stirring thoroughly until the gel material is gelled to obtain a polyelectrolyte hydrogel; After the polyelectrolyte hydrogel is stacked on the surface of a two-dimensional layered material film and placed between two oppositely disposed electrodes, a memristor with a biological synaptic structure is obtained.

[0009] Based on the above technical scheme, in a memristor with a biomimetic synaptic structure and a preparation method thereof provided by the present invention, electrodes, polyelectrolyte hydrogels and crown ether-doped two-dimensional materials are used to simulate the presynaptic membrane, synaptic cleft and postsynaptic membrane structures in biological synapses, respectively. Among them, the electrode on the polyelectrolyte hydrogel layer simulates the presynaptic membrane, the polyelectrolyte hydrogel layer simulates the synaptic cleft, the crown ether-doped two-dimensional material film layer simulates the postsynaptic membrane, and the metal transport ions provided by the electrode through the oxidation reaction simulate the neurotransmitter, and the memristor with a biomimetic synaptic structure is successfully prepared. The memristor with a biomimetic synaptic structure provided by the present invention provides metal transport ions through electrode oxidation reaction, the polyelectrolyte hydrogel layer provides a transmission channel to transmit the metal transport ions to the crown ether-doped two-dimensional material film layer, the crown ether molecules combine with the metal transport ions, thereby generating a memristor curve, and the overall conductivity of the memristor is adjustable by applying voltage to control the migration of metal transport ions in the crown ether-doped two-dimensional material film layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 A three-dimensional schematic diagram of a memristor according to the overall inventive concept of an embodiment of the present invention;

[0011] Figure 2 is a volt-ampere curve diagram of the memristor in Example 1 of the present invention;

[0012] Figure 3 is a pulse amplitude-dependent plasticity diagram of the memristor in Example 1 of the present invention;

[0013] Figure 4 is a retention time curve diagram of the memristor in Example 1 of the present invention;

[0014] Figure 5 This is a picowatt-level energy consumption diagram of the memristor in Example 1 of the present invention;

[0015] Figure 6 is a schematic diagram of a logic gate circuit constructed based on the memristor in Example 1 of the present invention;

[0016] Figure 7 for Figure 6 The result diagram of the operation of the logic gate circuit shown;

[0017] Figure 8 is a volt-ampere curve diagram of the memristor in Example 2 of the present invention;

[0018] Fig. 9 The volt-ampere curves of the memristors in Embodiments 1, 3 and 4 of the present invention;

[0019] Fig.10 is a volt-ampere curve diagram of the memristor in Example 5 of the present invention;

[0020] Fig.11 This is a peak current variation curve of the memristor in Example 5 of the present invention.

[0021] The symbols are explained as follows:

[0022] 100: memristor;

[0023] 1, 4: electrodes;

[0024] 2: polyelectrolyte hydrogel layer;

[0025] 3: Crown ether doped two-dimensional material film layer. DETAILED DESCRIPTION

[0026] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0027] The development of double-layer membrane structure ion memristor is mainly through the combination of solid polyelectrolyte layer and porous layered membrane. The solid polyelectrolyte layer provides the transmission ions, and the porous layered membrane acts as an ion receptor. By applying voltage to regulate the migration of ions in the polyelectrolyte layer in the receptor membrane, the conductivity is adjustable and non-volatile conductivity is achieved, which is specifically manifested in the memristor curve and biological synapse-like functions such as biological level retention time (ms-s), low operating voltage (5mV), and low energy consumption (16.7fw). Since the memristor heterostructure has rectification ratio performance, further construction of the circuit can also realize the logic gate function. Since the transmission ions in the current report come from the polyelectrolyte layer, the device ion selectivity is mostly for ions of the same group of elements, such as alkali metal ions Li + 、Na + and halogen ions Cl - Br - ,I - , while there are relatively few reports on the selectivity for element ions from different groups.

[0028] Therefore, the present invention provides a memristor with a biomimetic synaptic structure, which realizes a selective electrical response to the metal transport ions based on the combination of crown ether molecules and metal transport ions in a crown ether-doped two-dimensional material film layer, so that the memristor presents a conductance value related to the type of metal transport ions, which is crucial to realizing more powerful encoding and parallel computing capabilities of the memristor.

[0029] Figure 1 It is a three-dimensional schematic diagram of a memristor according to the general inventive concept of an embodiment of the present invention.

[0030] According to the general inventive concept of the present invention, Figure 1 As shown, a memristor 100 with a biomimetic synapse structure is provided, comprising: two electrodes 1 and 4 arranged opposite to each other; a crown ether-doped two-dimensional material film layer 3 located between the electrodes 1 and 4 and a polyelectrolyte hydrogel layer 2 located on the crown ether-doped two-dimensional material film layer 3.

[0031] Among them, when voltage is applied to electrodes 1 and 4, electrode 1 on the polyelectrolyte hydrogel layer 2 undergoes an oxidation reaction to produce metal transport ions, and the metal transport ions pass through the polyelectrolyte hydrogel layer 2 to reach the crown ether-doped two-dimensional material film layer 3. Based on the binding effect between the crown ether molecules and the metal transport ions in the crown ether-doped two-dimensional material film layer 3, a selective electrical response to the metal transport ions is achieved, so that the memristor 100 presents a conductivity value related to the type of metal transport ions.

[0032] In the memristor of the biomimetic synaptic structure of the embodiment of the present invention, the electrodes 1, 4, the polyelectrolyte hydrogel layer 2 and the crown ether doped two-dimensional material film layer 3 are respectively used to simulate the presynaptic membrane, synaptic cleft and postsynaptic membrane structure in the biological synapse. Among them, the electrode 1 on the polyelectrolyte hydrogel layer 2 simulates the presynaptic membrane, the polyelectrolyte hydrogel layer 2 simulates the synaptic cleft, the crown ether doped two-dimensional material film layer 3 simulates the postsynaptic membrane, and the metal transport ions provided by the electrode through the oxidation reaction simulate the neurotransmitter, and the memristor of the biomimetic synaptic structure is successfully prepared. The memristor of the biomimetic synaptic structure provided by the present invention provides metal transport ions through electrode oxidation reaction, the polyelectrolyte hydrogel layer provides a transmission channel to transmit the metal transport ions to the crown ether doped two-dimensional material film layer, the crown ether molecules combine with the metal transport ions, thereby generating a memristor curve, and the overall conductivity of the memristor is adjustable by applying voltage to control the migration of metal transport ions in the crown ether doped two-dimensional material film layer.

[0033] According to an embodiment of the present invention, the crown ether-doped two-dimensional material film layer 3 is formed by a two-dimensional material doped with a crown ether molecule. The two-dimensional material includes at least one of graphene oxide and MXene. The crown ether molecule includes at least one of 4'-aminobenzo-15-crown-5-ether, 4'-aminobenzo-18-crown-6, and aza-12-crown-4.

[0034] In the embodiments of the present invention, the crown ether molecules can selectively complex specific metal transport ions with their unique ring structure, improve the ion recognition ability of the memristor, and facilitate high-precision information storage in a multi-ion system. The metal transport ions are transmitted into the crown ether-doped two-dimensional material film layer through the polyelectrolyte hydrogel layer. Due to the different binding effects between the metal transport ions and the crown ether molecules, the migration amounts of the metal transport ions are different, resulting in different conductance values, thereby achieving the selective response of the memristor to different metal transport ion signals. In addition, the polyelectrolyte hydrogel layer can provide a transmission channel similar to liquid water, which increases the transmission rate of the metal transport ions and thus improves the response speed and working efficiency of the memristor.

[0035] The two-dimensional material layer structures are stacked or assembled into a porous structure, providing storage sites for metal transport ions, forming a stable three-dimensional ion transport channel network, and ensuring that the metal transport ion transport channels are not easy to collapse or block during the operation of the memristor. The two-dimensional material itself has good mechanical properties, which can enhance the overall strength and toughness of the crown ether-doped two-dimensional material film layer, resist the mechanical stress in the preparation and use of the memristor, and improve the bonding force between the film and other materials, extending the service life of the memristor. In addition, the two-dimensional material has certain electrical properties, which can interact with the crown ether and the metal transport ions to affect the electrical behavior of the crown ether-doped two-dimensional material film layer, such as participating in the charge transfer process as an electron acceptor or electron donor, affecting the conductivity and capacitance characteristics, and then affecting the resistance switching characteristics of the memristor. Moreover, its electrical properties can be adjusted, providing a way to optimize the electrical performance of the memristor.

[0036] According to an embodiment of the present invention, the polyelectrolyte hydrogel layer 2 is formed of a polyelectrolyte material and a gel material. The polyelectrolyte material includes at least one of polystyrene sulfonic acid, sodium polystyrene sulfonate, potassium polystyrene sulfonate, polyacrylic acid, sodium polyacrylate, potassium polyacrylate, polymethacrylic acid, sodium polymethacrylate, potassium polymethacrylate, polyethylene sulfonic acid, sodium polyethylene sulfonate, potassium polyethylene sulfonate, polyethylene phosphoric acid, sodium polyethylene phosphate, and potassium polyethylene phosphate; the gel material includes at least one of a polysaccharide gel material, a polypeptide gel material, and an acrylic gel material. The polysaccharide gel material includes at least one of starch, cellulose, alginate, and hyaluronic acid chitosan; the polypeptide gel material includes at least one of collagen, poly-L-lysine, and poly-L-glutamic acid; the acrylic gel material includes at least one of polyacrylic acid, polymethacrylic acid, polyacrylamide, and poly-N-polyacrylamide.

[0037] In an embodiment of the present invention, the polyelectrolyte material itself has ion conduction capability and can provide a migration channel for metal transport ions. During the operation of the memristor, the metal transport ions can move along the molecular chain of the polyelectrolyte material or its internal structure, thereby realizing the transmission of charge, which is crucial for the realization of electrical properties such as resistance transformation of the memristor and is one of the foundations for ensuring its normal operation. The polyelectrolyte material can adjust the electrical properties of the polyelectrolyte hydrogel layer through its own chemical structure and properties, such as affecting parameters such as capacitance and resistance. Different types of polyelectrolyte materials have different electrical properties. By selecting suitable polyelectrolyte materials, the electrical properties of the memristor can be optimized so that it can achieve stable resistance switching characteristics under specific voltage, current and other conditions. In the polyelectrolyte hydrogel layer, the polyelectrolyte material and the gel material cooperate with each other, and it can interact with the gel material, such as forming chemical bonds or physical adsorption, etc., to jointly construct a stable and well-functioning polyelectrolyte hydrogel layer structure, thereby contributing to the performance improvement of the entire memristor.

[0038] The gel material can form a structure similar to a three-dimensional network, providing certain physical support for the polyelectrolyte hydrogel layer, giving it a certain shape and stability. At the same time, the gel material usually has good flexibility, which enables the polyelectrolyte hydrogel layer to adapt well to external forces (such as pressure, bending, etc. that may be encountered during the preparation, packaging or actual use of the memristor) without being easily broken or damaged, thus ensuring the integrity of the memristor structure. The network structure inside the gel material can store a certain amount of ions, and its network structure also provides additional channels and paths for the transmission of metal transport ions, which cooperates with the ion conduction of the polyelectrolyte material to further promote the migration of metal transport ions in the polyelectrolyte hydrogel layer, which helps to improve the ion transmission efficiency and overall performance of the memristor. In addition, the gel material can adjust some physical and chemical properties of the polyelectrolyte hydrogel layer, such as adjusting its water absorption and moisture retention. Suitable gel materials can enable the polyelectrolyte hydrogel layer to maintain relatively stable performance under different environmental conditions (such as humidity changes, etc.), avoid performance degradation caused by environmental factors, and thus extend the service life of the memristor.

[0039] According to an embodiment of the present invention, the thickness of the crown ether-doped two-dimensional material film layer 3 is 3-4 μm, and the thickness of the crown ether-doped two-dimensional material film layer affects the length and density of the metal transmission ion transmission channel. A thinner crown ether-doped two-dimensional material film layer means that the metal transmission ion transmission channel is relatively short, which is conducive to the rapid passage of metal transmission ions and can improve the response speed of the memristor. At the same time, the thinner film has a relatively high pore density (other conditions remain unchanged), which can provide more transmission paths for metal transmission ions and further promote the transmission of metal transmission ions. However, too thin crown ether-doped two-dimensional material film layers will lead to insufficient mechanical strength, which is easy to be damaged during preparation or use, affecting the service life of the memristor. A crown ether-doped two-dimensional material film layer of appropriate thickness helps to maintain good metal transmission ion selectivity and storage capacity. The thickness of the crown ether-doped two-dimensional material film layer will affect the selective complexation of the crown ether to the metal transmission ions and the storage of the metal transmission ions in the crown ether-doped two-dimensional material film. If it is too thick, the diffusion path of metal transport ions in the crown ether-doped two-dimensional material membrane layer will become longer, which will reduce the selectivity of metal transport ions and is not conducive to the effective storage of metal transport ions; if it is too thin, it will not provide enough space to achieve effective selective complexation and storage of metal transport ions.

[0040] According to an embodiment of the present invention, the thickness of the polyelectrolyte hydrogel layer 2 is 0.1-1cm. A thinner polyelectrolyte hydrogel layer can allow the metal transport ions to pass more quickly, because the migration path is relatively short and the resistance is relatively small, which helps to improve the transmission efficiency of the metal transport ions in the memristor, so that the memristor can achieve the transition of the resistance state in a shorter time, and improve the response speed. However, if it is too thin, it is impossible to provide enough storage sites for the metal transport ions, which affects the effective storage of the metal transport ions and the electrical performance stability of the memristor. A polyelectrolyte hydrogel layer of appropriate thickness is essential for maintaining stable electrical properties. An overly thick polyelectrolyte hydrogel layer will increase the resistance of the metal transport ion transmission, resulting in difficulty in the passage of current, thereby affecting the resistance switching characteristics of the memristor, making the resistance transition not sensitive enough or unstable. At the same time, being too thick will affect the interaction with the crown ether-doped two-dimensional material film layer and the electric field distribution of the overall device, which is not conducive to the normal operation of the memristor.

[0041] In an embodiment of the present invention, the thickness of the crown ether-doped two-dimensional material film layer and the polyelectrolyte hydrogel layer are matched. If the thickness ratio is not coordinated, for example, the crown ether-doped two-dimensional material film layer is too thick or too thin, the overall balance of the memristor structure will be destroyed, affecting the transmission and storage of metal transport ions between the two layers, thereby reducing the overall performance of the memristor.

[0042] As an embodiment of another aspect of the present invention, a method for preparing the above-mentioned memristor is provided, comprising: Adding crown ether molecules and two-dimensional materials into water, mixing them evenly and forming a film, thereby obtaining a crown ether-doped two-dimensional material film; Adding the gel material to the polyelectrolyte aqueous solution and stirring thoroughly until the gel material is gelled to obtain a polyelectrolyte hydrogel; After the polyelectrolyte hydrogel is stacked on the surface of a two-dimensional layered material film and placed between two oppositely disposed electrodes, a memristor with a biological synaptic structure is obtained.

[0043] In an embodiment of the present invention, a crown ether-doped two-dimensional material film is prepared by a blending method, a polyelectrolyte hydrogel is prepared by a hydrothermal method, and the crown ether-doped two-dimensional material film and the polyelectrolyte hydrogel are stacked and placed in an electrode to obtain a memristor with a biomimetic synapse structure. The preparation method of the memristor with a biomimetic synapse structure provided by the present invention has a simple preparation process, is easy to operate and implement, has simple requirements for experimental equipment and experimental conditions, and is suitable for large-scale promotion.

[0044] According to an embodiment of the present invention, the mass ratio of crown ether molecules to two-dimensional materials is 1:0.3-2. When the ratio of crown ether molecules to two-dimensional materials is not appropriate, the resistance variation range of the memristor will become smaller or unstable. If the ratio of crown ether molecules is too high, the storage of metal transport ions in the memristor will be too dispersed, and a stable resistance state cannot be effectively formed; if the ratio of crown ether molecules is too low, the migration of metal transport ions will be difficult, and it will be difficult to achieve a good conversion of the resistance state.

[0045] According to an embodiment of the present invention, the mass ratio of the polyelectrolyte material to the gel material is 1-5: 1. By changing the amount of polyelectrolyte added, the polyelectrolyte content in the polyelectrolyte hydrogel can be changed, thereby changing the ion transfer efficiency.

[0046] According to an embodiment of the present invention, the mass of the gel material is 2-5% of the mass of water in the polyelectrolyte aqueous solution. A high proportion of gel material means good strength and toughness, while a high proportion of water means softness and elasticity but poor stability. A high proportion of gel material means that the channel is dominated by the hydrogel network, which will hinder the movement of metal transport ions but can selectively adsorb metal transport ions; a high proportion of water is conducive to the diffusion of metal transport ions, but too high a proportion will weaken the interaction with active sites. A high proportion of gel material means that the gelation process is faster but prone to unevenness, while a high proportion of water means that the gelation process is slower.

[0047] Specifically, the present invention exemplarily provides a specific preparation method of a polyelectrolyte hydrogel: add 50-700 mg of sodium polystyrene sulfonate powder to a beaker, dissolve it in 10-200 ml of deionized water, and stir at room temperature until it is completely dissolved; add 50-400 mg of agarose to the beaker, heat and stir at 60-95°C for about 3 hours or more until the agarose is completely dissolved without obvious bubbles; pour the liquid in the beaker into a culture dish, leave it at room temperature, and cool the liquid to form a sodium polystyrene sulfonate hydrogel.

[0048] Similarly, the present invention exemplarily provides a specific preparation method for a crown ether-doped two-dimensional material film: weigh 5-200 mg of graphene oxide powder and 5-200 mg of 4'-aminobenzo-15-crown 5-ether powder, dissolve them in 10-200 ml of deionized water, stir for 1-3 days, and then put them in ultrasonic oscillation for more than 2 hours; vacuum filter for 1-3 days to obtain a crown ether-doped graphene oxide film.

[0049] The present invention is further described below by examples and related test experiments. In the detailed description below, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present invention. However, it is obvious that one or more embodiments may also be implemented without these specific details. And, in the absence of conflict, the details in the following embodiments may be combined into other feasible embodiments at will. All instruments, consumables and reagents in the following examples, if not otherwise specified, may be obtained from commercial sources.

[0050] Example 1

[0051] In this embodiment 1, a memristor with a synaptic structure is prepared by the following steps.

[0052] Firstly, crown ether-doped graphene oxide film was prepared by blending method, and the specific preparation steps are as follows.

[0053] Weigh 10 mg of graphene oxide powder and 5 mg of 4'-aminobenzo-15-crown 5-ether powder, dissolve in 50 ml of deionized water, stir for 1 day, and then put into ultrasonic oscillation for 5 hours; vacuum filter for 1 day to form a film.

[0054] Then, a sodium polystyrene sulfonate hydrogel layer was prepared by a hydrothermal method, and the specific preparation steps are as follows.

[0055] Add 700 mg of sodium polystyrene sulfonate powder to a beaker and dissolve it in 20 ml of deionized water. Stir at room temperature until it is completely dissolved. Add 300 mg of agarose to the beaker and heat and stir at 90°C for about half an hour until the agarose is completely dissolved without obvious bubbles. Pour the above liquid into a culture dish and leave it at room temperature. The liquid will cool to form a sodium polystyrene sulfonate hydrogel.

[0056] Finally, the prepared 4'-aminobenzo-15-crown 5-ether doped graphene oxide film was stacked with sodium polystyrene sulfonate hydrogel, and zinc electrodes were sandwiched on both sides to obtain a memristor.

[0057] Figure 2 This is a volt-ampere curve of the memristor in Example 1 of the present invention.

[0058] like Figure 2 As shown in FIG. 1 , different voltages are applied to the memristor in Example 1 of the present invention to measure the cyclic voltammetry curve (IV curve) of the memristor. Figure 2It can be understood that the peak current increases with the increase of the number of scans, proving that the memristor conductance of this embodiment is adjustable, that is, it has synaptic plasticity. When voltage is applied to the memristor of this embodiment and IV cycle scan is performed, the peak current increases significantly under the forward voltage, proving that the conductance of the memristor in this embodiment 1 is adjustable with the applied voltage frequency time; the current peak does not change significantly under the reverse voltage, proving that the memristor of this embodiment has an obvious rectification ratio; in a single IV scan, the current presents an 8-shaped hysteresis curve, which meets the definition of a memristor.

[0059] Figure 3 Graph showing the pulse amplitude-dependent plasticity of the memristor in Example 1 of the present invention.

[0060] like Figure 3 As shown, in Example 1 of the present invention, 20 pulse voltage signals are applied to the memristor, with the amplitude of the pulse voltage being a variable. The device current response is different under different voltage amplitudes. Figure 3 The curve shown proves that the voltage amplitude-dependent plasticity of the memristor of this embodiment is such that the memristor can recognize a minimum amplitude of 0.2V.

[0061] Figure 4 This is a retention time curve diagram of the memristor in Example 1 of the present invention.

[0062] like Figure 4 As shown, in Example 1 of the present invention, 10 pulse voltages with a pulse width of 10 ms and an interval of 10 ms are applied to the memristor, and the amplitude is 0.1-0.9 V. In the figure, when the voltage is 0, the current slowly returns to the baseline, and the retention time is in the ms level. Figure 4 The curve shown demonstrates the non-volatility of the memristor conductance of this embodiment.

[0063] Figure 5 This is a picowatt-level energy consumption diagram of the memristor in Example 1 of the present invention.

[0064] like Figure 5 As shown, when a voltage of the same order of magnitude as the biological synaptic operating voltage (mV) is applied to the memristor in Example 1 of the present invention, the average power consumed by a single synaptic event is 44.5 pW (given by Ipeak×V). Figure 5 The curve shown proves that the working power (pW) of the memristor of this embodiment is of the same order of magnitude as that of the biological synapse.

[0065] Figure 6 is a schematic diagram of a logic gate circuit constructed based on the memristor in Example 1 of the present invention, wherein the memristor in Example 1 of the present invention is used as Figure 6 The diode in Figure 7 for Figure 6 The diagram shows the operation results of the logic gate circuit.

[0066] like Figure 6-Figure 7 As shown in Figure 2, since the memristor heterostructure has a certain rectification ratio (3-50, related to the applied electric field history), according to Figure 6 As shown in the figure, a logic gate circuit is constructed, and two input signal variables are set, namely the input bias voltage and the switching state of the diode. Figure 7 The curves shown prove that the logic gate circuit constructed based on the memristor in Example 1 of the present invention realizes the functions of the logic gates "OR" and "AND" under different bias voltages.

[0067] Example 2

[0068] In this embodiment 2, a memristor with a synaptic structure is prepared. The preparation method is the same as that in embodiment 1, except that the electrolyte material used in this embodiment 2 is polystyrene sulfonic acid. The specific preparation method is as follows.

[0069] Add 700 mg of polystyrene sulfonic acid powder to a beaker and dissolve it in 20 ml of deionized water, and stir at room temperature until it is completely dissolved. Add 300 mg of agarose to the beaker, heat and stir at 90 °C for more than half an hour until the agarose is completely dissolved without obvious bubbles. Pour the liquid into a culture dish, leave it at room temperature for half an hour, and then cool the liquid to form a polystyrene sulfonic acid hydrogel.

[0070] Figure 8 This is a volt-ampere curve diagram of the memristor in Example 2 of the present invention.

[0071] like Figure 8 As shown, a voltage is applied to the memristor to measure the cyclic voltammetry curve (IV curve) of the memristor in this embodiment 2, Figure 8 The curve shown shows that the memristor of this embodiment has memristive characteristics and the conductance is adjustable.

[0072] Example 3

[0073] In this embodiment 3, a memristor with a synaptic structure is prepared. The preparation method is the same as that in embodiment 1, except that the electrode material used in this embodiment 3 is an iron sheet.

[0074] Example 4

[0075] In this embodiment 4, a memristor with a synaptic structure is prepared. The preparation method is the same as that in embodiment 1, except that the electrode material used in this embodiment 4 is a copper sheet.

[0076] Fig. 9 The volt-ampere curves of the memristors in Embodiments 1, 3 and 4 of the present invention are shown.

[0077] like Fig. 9 As shown, a voltage is applied to a memristor using different metal materials (iron, zinc, copper) as electrodes. Fig. 9The IV curves shown illustrate the dependence of the hysteresis loop area on the type of active electrode, i.e., achieving selective transmission of ion signals.

[0078] Example 5

[0079] In this embodiment 5, a memristor with a synaptic structure is prepared. The preparation method is the same as that in embodiment 1, except that: in this embodiment 5, the graphene oxide film is prepared by a vacuum filtration method.

[0080] Fig.10 is a volt-ampere curve diagram of the memristor in Example 5 of the present invention; Fig.11 This is a peak current variation curve of the memristor in Example 5 of the present invention.

[0081] like Figure 10-11 As shown, a voltage is applied to the memristor in Example 5 of the present invention to measure the cyclic voltammetry curve (IV curve) of the memristor. The test results show that the conductance change of the memristor in this embodiment is unstable and tends to saturation. Fig.11 The figure shows the peak current change value. After replacing it with crown ether-doped graphene oxide film, a continuously enhanced conductivity signal can be observed ( Figure 2 ). It is proved that the doping of crown ether increases the interlayer spacing and ion storage sites of the two-dimensional material film, achieving an enhanced memory signal.

[0082] In summary, in the memristor with a biomimetic synaptic structure provided by the present invention, the polyelectrolyte hydrogel can realize pressure-sensitive, temperature-sensitive, and humidity-sensitive responses, which is helpful to realize the interactive perception and information processing of the environment by the memristor; the crown ether-doped two-dimensional material film is doped with crown ether molecules into the channels between the two-dimensional materials by a simple blending method, and different conductivity values ​​are generated by the different binding effects of the crown ether molecules on different metal ions, thereby realizing the selective response of the memristor to different metal ion signals. The present invention generates metal transmission ions through electrode oxidation reactions to realize selective responses to elements of different groups, and provides a new idea for realizing multi-ion selective responses of ion memristors. The present invention realizes multi-ion selective responses of memristors by compounding electrodes and crown ether-doped two-dimensional material films, and the crown ether molecules have different binding abilities to different metal ions. In addition, the memristor with a biomimetic synaptic structure provided by the present invention realizes memristive curves and various types of biological synaptic phenomena such as biological level retention time (ms), low operating voltage (0.2V), and low energy consumption (16.7fw). The heterogeneous structure of the memristor with a biomimetic synaptic structure provided by the present invention enables it to have a high rectification ratio. By constructing a circuit and setting two input signal variables, namely the input bias voltage and the switching state of the diode, the functions of the logic gates "OR" and "AND" are realized under different bias voltages, laying the foundation for the construction of future artificial nanofluidic neural networks.

[0083] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A memristor with a biological synaptic structure, comprising: two electrodes arranged opposite to each other; as well as A crown ether-doped two-dimensional material film layer located between the electrodes and a polyelectrolyte hydrogel layer located on the crown ether-doped two-dimensional material film layer; Among them, when a voltage is applied to the electrode, an oxidation reaction occurs at the electrode on the polyelectrolyte hydrogel layer to produce metal transport ions, and the metal transport ions pass through the polyelectrolyte hydrogel layer to reach the crown ether-doped two-dimensional material film layer. Based on the binding effect between the crown ether molecules in the crown ether-doped two-dimensional material film layer and the metal transport ions, a selective electrical response to the metal transport ions is achieved, so that the memristor presents a conductivity value related to the type of the metal transport ions.

2. The memristor according to claim 1, wherein: The crown ether-doped two-dimensional material film layer is formed by a two-dimensional material doped with crown ether molecules; The polyelectrolyte hydrogel layer is formed of a polyelectrolyte material and a gel material.

3. The memristor according to claim 2, wherein: The two-dimensional material includes at least one of graphene oxide and MXene; The crown ether molecule includes at least one of 4'-aminobenzo-15-crown-5-ether, 4'-aminobenzo-18-crown-6-ether, and aza-12-crown-4-ether.

4. The memristor according to claim 2, wherein: The polyelectrolyte material comprises at least one of polystyrene sulfonic acid, sodium polystyrene sulfonate, potassium polystyrene sulfonate, polyacrylic acid, sodium polyacrylate, potassium polyacrylate, polymethacrylic acid, sodium polymethacrylate, potassium polymethacrylate, polyethylene sulfonic acid, sodium polyethylene sulfonate, potassium polyethylene sulfonate, polyethylene phosphoric acid, sodium polyethylene phosphate, and potassium polyethylene phosphate; The gel material includes at least one of a polysaccharide gel material, a polypeptide gel material, and an acrylic gel material.

5. The memristor according to claim 4, wherein: The polysaccharide gel material includes at least one of starch, cellulose, alginate, and hyaluronic acid chitosan; The polypeptide gel material includes at least one of collagen, poly-L-lysine, and poly-L-glutamic acid; The acrylic gel material includes at least one of polyacrylic acid, polymethacrylic acid, polyacrylamide and poly-N-polyacrylamide.

6. The memristor according to any one of claims 1 to 5, wherein: The thickness of the crown ether-doped two-dimensional material film layer is 3-4 μm; The thickness of the polyelectrolyte hydrogel layer is 0.1-1 cm.

7. A method for preparing a memristor according to any one of claims 1 to 6, comprising: Adding crown ether molecules and two-dimensional materials into water, mixing them evenly and forming a film, thereby obtaining a crown ether-doped two-dimensional material film; Adding the gel material to the polyelectrolyte aqueous solution and stirring thoroughly until the gel material is gelled to obtain a polyelectrolyte hydrogel; After the polyelectrolyte hydrogel is stacked on the surface of the two-dimensional layered material film, it is placed between two oppositely arranged electrodes to obtain a memristor that mimics a biological synapse structure.

8. The method according to claim 7, wherein: The mass ratio of the crown ether molecule to the two-dimensional material is 1:0.3-2.

9. The method according to claim 7, wherein: The mass ratio of the polyelectrolyte material to the gel material is 1-5:

1.

10. The method according to claim 7, wherein: The mass of the gel material is 2-5% of the mass of water in the polyelectrolyte aqueous solution.

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