Artificial synapse device of light-controlled nano fluid ion transistor

Abstract

The invention relates to an artificial synaptic device of a light-controlled nanofluid ion transistor, and belongs to the field of preparation of electronic devices. Comprising a nanofluid ion transistor, an electrolyte solution, a working electrode and a reference electrode, the working electrode and the reference electrode are arranged in the electrolyte solution and are respectively used as a source electrode and a drain electrode of the nanofluid ion transistor; the quantity of electric charges on the surface of the nanofluid ion transistor is changed through optical signal input, so that the basic synaptic functions of short-term plasticity, conversion from the short-term plasticity to the long-term plasticity and the like are realized through optical regulation and control of ion migration. Meanwhile, when the nerve conditioning ascorbic acid AA with reducibility is added, the plasticity of the system can be enhanced by chemical regulation and control. Furthermore, by means of the good synaptic plasticity-like capacity of the device, 'Baplov dog 'experiment simulation and'international Morse password' coding can be achieved. The device disclosed by the invention provides a good foundation for the development of neuromorphism.

Description

Technical Field

[0001] The invention relates to an artificial synaptic device of a light-regulated nanofluidic ion transistor, belonging to the field of electronic device preparation. Background Art

[0002] With the continuous development of science and technology, the traditional von Neumann computing architecture is facing the bottleneck of low speed and low efficiency due to the separation of computing and storage units. Inspired by the efficient and parallel operation of the brain, artificial neural synaptic devices are constantly developing, mainly including two-terminal memristors and three-terminal / multi-terminal transistors. The device has a history-dependent conductivity memory capability, which can be used to simulate basic functions similar to synapses, and further realize advanced functions such as neuromorphic computing and image / information recognition. At present, the development of artificial synaptic devices is mainly focused on solid-state devices with electrons as carriers. Their main mechanisms are conductive bridge, ferroelectric principle, phase change principle, migration of oxygen vacancies, etc., which are different from the real physiological environment with ions as carriers. Therefore, artificial synaptic devices with ions as carriers are in urgent need of development. In addition, in addition to using voltage as a stimulus source to regulate ionic conductivity, optical signals as a stimulus source have the characteristics of strong remote controllability and precise and rapid response regulation. Therefore, the development of light-regulated nanofluid ion transistors with light as a stimulus source is of great significance to the development of artificial neural synaptic devices. Summary of the invention

[0003] The purpose of the present invention is to provide an artificial synaptic device of a light-controlled nanofluid ion transistor. The ion transistor of the present invention can be light-controlled in a liquid environment, and ions are used as carriers to be closer to the real physiological environment. When the ion transistor of the present invention is stimulated by a light pulse, it can generate an excitatory postsynaptic current similar to a neuronal synapse. By changing the waveform of the input light signal, the migration dynamics of the ions can be regulated, thereby causing a change in the output current, and realizing the simulation of basic synaptic functions such as short-term plasticity and the transition from short-term plasticity to long-term plasticity. At the same time, when the reducing neuromodulator ascorbic acid AA is added, the plasticity of the system can be enhanced by chemical regulation. Furthermore, by utilizing the good synaptic plasticity of the device, the simulation of the "Pavlov's Dog" experiment and the encoding of the "International Morse Code" can also be realized. The light-controlled nanofluid ion transistor of the present invention has a good ability to simulate synaptic plasticity by light-controlled ion migration, which helps to promote new developments in neural morphology.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] The present invention discloses an artificial synaptic device of a light-regulated nanofluidic ion transistor, comprising: a nanofluidic ion transistor, an electrolyte solution, a working electrode and a reference electrode; the working electrode and the reference electrode are placed in the electrolyte solution, and serve as the source and drain of the nanofluidic ion transistor respectively; the input of a light signal changes the surface charge of the nanofluidic ion transistor, thereby realizing a synaptic-like function by light-regulating the migration of ions.

[0006] The nanofluid ion transistor comprises: an anodic aluminum oxide film AAM and Al-TCPP MOFs in-situ grown in the pores of the AAM; the Al-TCPP MOFs are obtained by adding tetra-carboxyphenylporphyrin TCPP into the anodic aluminum oxide film AAM.

[0007] The AAM has uniform double channels, thicknesses of 40 μm, 65 μm, 90 μm, and 120 μm, and a wide range of pore sizes, mainly 20-300 nm.

[0008] The preparation method of the nanofluid ion transistor is as follows:

[0009] (1) DMF and H2O are mixed in a volume ratio of 3:1 to obtain a mixed solvent; TCPP having a mass fraction of 0.26% to 0.38% is dissolved in the mixed solvent to form a mixture; ultrasonication is performed to allow TCPP to fully enter the pores of AAM; and the mixture is transferred into a sealed bottle;

[0010] (2) placing the sealed bottle in a microwave synthesizer and reacting at 140° C. for not less than 1 h to obtain an AAM-Al-TCPP MOFs membrane, i.e., MOFM;

[0011] (3) The MOFM was washed three times with DMF and acetone respectively, and then dried at room temperature to remove excess solvent to obtain a nanofluidic ion transistor.

[0012] The electrolyte solution is KCl solution.

[0013] The working electrode and the reference electrode are both Ag / AgCl.

[0014] The method for measuring ion flow using the artificial synaptic device of the light-regulated nanofluidic ion transistor is as follows: the light signal input enhances the surface negative charge of the nanofluidic ion transistor, causing an increase in the migration of carrier cations, which will be neutralized by the electrons on the Ag / AgCl electrode when they reach the vicinity of the electrode, or the excess electrons will be drawn away by the electrode, causing a redox reaction, forming the flow of electrons, which is manifested as a change in current.

[0015] In the present invention, the maximum absorption peak positions of the ultraviolet-visible absorption spectra of TCPP and Al-TCPP MOFs are both at 420 nm, so the 420 nm light source can achieve the maximum efficiency regulation of the ionic conductivity of the ionic transistor.

[0016] Beneficial effects:

[0017] 1. The present invention discloses an artificial synaptic device based on a light-regulated nanofluidic ion transistor, which has a good ability to simulate synaptic plasticity by light-regulated ion migration. When light pulse stimulation is applied, it can generate excitatory postsynaptic currents similar to those of neuronal synapses, thereby simulating basic synaptic functions such as short-term plasticity and the transition from short-term plasticity to long-term plasticity.

[0018] 2. The present invention discloses an artificial synaptic device based on a light-regulated nanofluidic ion transistor, which can enhance the plasticity of the system by chemical regulation when the reducing neuromodulator ascorbic acid AA is added.

[0019] 3. The present invention discloses an artificial synaptic device based on a light-regulated nanofluidic ion transistor. By utilizing the good synaptic plasticity of the device, the simulation of the "Pavlov's Dog" experiment and the encoding of the "International Morse Code" can be realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a macroscopic structural photo of the ionic transistor prepared according to the present invention;

[0021] Figure 2 This is a scanning electron microscope microstructure diagram of the ionic transistor prepared according to the present invention;

[0022] Figure 3 A schematic diagram of an artificial synapse device provided in Example 1;

[0023] Figure 4 The IV curve of the artificial synaptic device provided in Example 1 scanned at different optical power densities;

[0024] Figure 5 A and 5B are schematic diagrams of excitatory postsynaptic current and double pulse facilitation obtained by the artificial synaptic device provided in Example 1 under single and double light pulse conditions;

[0025] Figure 6 A double exponential function curve obtained by fitting the double-pulse facilitation index and the post-tetanic potentiation index obtained by repeatedly changing the pulse interval of the artificial synaptic device provided in Example 1;

[0026] Figure 7 The artificial synaptic device provided in Example 1 realizes the transition from short-term plasticity to long-term plasticity by changing the pulse time;

[0027] Figure 8 The artificial synaptic device provided in Example 1 realizes the transition from short-term plasticity to long-term plasticity by changing the number of pulses;

[0028] Fig. 9 A and 9B are the artificial synaptic devices provided in Example 1, which enhance synaptic plasticity by chemical regulation through the neuromodulator ascorbic acid (B is a partial enlarged view of A);

[0029] Fig.10 The artificial synaptic device provided in Example 1 simulates the "Pavlov's dog" experiment;

[0030] Fig.11 The artificial synaptic device provided in Example 1 realizes the encoding of "International Morse Code";

[0031] Fig.12 The photocurrent response results of the artificial synaptic device provided in Comparative Example 1 under three conditions: empty slot, AAM and MOFM. DETAILED DESCRIPTION

[0032] In order to better illustrate the purpose and advantages of the present invention, the invention is further described below with reference to the accompanying drawings and examples.

[0033] Embodiment 1:

[0034] 1. This embodiment discloses an artificial synaptic device of a light-controlled nanofluidic ion transistor, comprising: a nanofluidic ion transistor, an electrolyte solution, a working electrode and a reference electrode; the working electrode and the reference electrode are placed in the electrolyte solution, serving as the source and drain of the nanofluidic ion transistor respectively; the optical signal input changes the surface charge of the nanofluidic ion transistor, thereby realizing a synaptic-like function by light-controlled ion migration.

[0035] The nanofluid ion transistor comprises: an anodic aluminum oxide film AAM and Al-TCPP MOFs in-situ grown in the pores of the AAM; the Al-TCPP MOFs are obtained by adding tetra-carboxyphenylporphyrin TCPP into the anodic aluminum oxide film AAM.

[0036] The AAM has a uniform double channel. The thickness is 40 μm, 65 μm, 90 μm, and 120 μm. The pore size range is wide, mainly 20-300 nm. The AAM used in this embodiment has a thickness of 40 μm and a pore size of 80-100 nm.

[0037] The preparation method of the nanofluid ion transistor is as follows:

[0038] (1) DMF and H2O were mixed in a volume ratio of 3:1 to obtain 4 ml of a mixed solvent; 10 mg of TCPP was dissolved in the mixed solvent to form a mixture; ultrasonication was performed to allow TCPP to fully enter the AAM pores; and the mixture was transferred to a sealed bottle;

[0039] (2) placing the sealed bottle in a microwave synthesizer and reacting at 140° C. for 1 h to obtain an AAM-Al-TCPP MOFs membrane, i.e., MOFM;

[0040] (3) The MOFM was washed three times with DMF and acetone respectively, and then dried at room temperature to remove excess solvent to obtain a nanofluidic ion transistor.

[0041] The electrolyte solution is KCl solution.

[0042] The working electrode and the reference electrode are both Ag / AgCl.

[0043] The method for measuring ion flow using the artificial synaptic device of the light-regulated nanofluidic ion transistor is as follows: the light signal input enhances the surface negative charge of the nanofluidic ion transistor, causing an increase in the migration of carrier cations, which will be neutralized by the electrons on the Ag / AgCl electrode when they reach the vicinity of the electrode, or the excess electrons will be drawn away by the electrode, causing a redox reaction, forming the flow of electrons, which is manifested as a change in current.

[0044] In the present invention, the maximum absorption peak positions of the ultraviolet-visible absorption spectra of TCPP and Al-TCPP MOFs are both at 420 nm, so the 420 nm light source can achieve the maximum efficiency regulation of the ionic conductivity of the ionic transistor.

[0045] 2. Single device photoresponse characteristics test

[0046] like Figure 3 The MOFM was placed between two electrolytic cells made of polymethyl methacrylate (PMMA), which contained 1 mM KCl electrolyte solution. The electrochemical test was performed using a CHI 660E (Shanghai Chenhua) electrochemical workstation, and two Ag / AgCl electrodes protected by polytetrafluoroethylene sleeves measured the transmembrane ion current. A UV LED ultraviolet curing device was used as the light source emitter, and the lamp head could be replaced according to the required light wavelength.

[0047] like Figure 4 , triangle wave scanning range -1V~1V, scanning speed 50mV / s, it can be found that with the increase of light power, the IV curve conductivity also gradually increases, indicating that the ion transistor has good photoelectric response ability. In order to ensure the photoelectric response ability while protecting the life of the light source, the light power used in this embodiment is mainly 58.8mW / cm 2, other optical powers were obtained as control tests. Figure 5 A It test was performed under the condition of constant voltage of 50mV. When the light was illuminated for 5s, obvious excitatory postsynaptic current could be observed. Figure 5 B shows the occurrence of double-pulse facilitation behavior when two consecutive light pulses are applied, proving the existence of its synaptic properties.

[0048] 3. Basic synaptic function simulation

[0049] The nanofluidic ion transistor is connected to an external test circuit, and the short-term plasticity of the ion transistor is determined based on the value of the electrical signal output by the electrical signal detector. Figure 6 As shown in the figure, under continuous light pulses, the double exponential function curve obtained by fitting the decay trend of the device ion current change with the pulse interval can show the strength of the short-term plasticity of the artificial synaptic device. When the double pulse facilitation index is close to 1, it means that the plasticity at this time is very weak. Among them, the constant voltage applied is still 50mV, and the duration of the fixed light pulse t d =0.5s, only the interval of the light pulse Δt is changed from 0.2 to 10s.

[0050] By changing the duration and number of light pulses, the transition from short-term plasticity to long-term plasticity can be achieved. Figure 7 As shown in the figure, the fixed optical pulse interval Δt is 0.5s. d From 0.5s to 2s, after ten consecutive pulses, the tenth pulse current value increases successively; Figure 8 As shown, the fixed pulse duration t d The pulse duration is 0.5s, and the pulse interval Δt is 0.2s. As the number of pulses increases, the current value of the last pulse also increases.

[0051] 4. Chemical regulation of synaptic plasticity

[0052] Based on the above, the addition of ascorbic acid before applying light pulses for chemical regulation can achieve the enhancement of synaptic plasticity. Fig. 9 As shown in A and 9B, 3 μM AA was added to 1 mM KCl. Under the same light pulse conditions, the current value after adding AA was higher than the current value without adding AA. AA, as a hole sacrificial agent, enhanced the negative charge of the ionic transistor under light conditions, resulting in an increase in ionic current, thus achieving the enhancement of chemically regulated synaptic plasticity.

[0053] 5. Simulation of the "Pavlov's Dog" experiment and the encoding of the "International Morse Code"

[0054] By utilizing the good synaptic-like capabilities of the above-mentioned nanofluidic ion transistors, in addition to simulating basic synaptic functions, it is also possible to realize the "Pavlov's Dog" experiment simulation and the encoding of the "International Morse Code". Specifically, Fig.10 As shown, the light pulse duration t d 3s, pulse interval Δt is 0.5s, 21.3mW / cm 2 The light power of the stimulus represents the ringing tone, 39.5mW / cm 2 The light power stimulus represents food, which can make the puppy drool, while 60.8mW / cm 2 The light power stimulation represents the combination of the two, which can also make the puppy drool. It is a process of continuous training, thus forming a conditioned reflex. After that, only the bell is used for stimulation. For a period of time, the puppy will still drool when hearing the bell. But as time goes by, there will be no more drooling, indicating that the conditioned reflex disappears.

[0055] The current waveforms formed by the stimulation of light pulses of different lengths can be combined to represent 26 letters, and different letters can be combined to form a word. Specifically, the current value formed by a pulse of 3s represents a line, and the current value formed by a pulse of 1s represents a point. For example, the letter "B" is represented by "line-point-point-point", which is reflected in the form of light pulses: pulse 3s-1s-1s-1s, and the middle pulse interval Δt is 3s. Fig.11 As shown, using the above method, words such as "HELLO" can be encoded using the international Morse code to achieve the information transmission function.

[0056] Comparative Example 1:

[0057] In the comparative example, an empty electrolytic cell and a bare AAM were used to conduct a photoresponse current test to illustrate that the key to generating the photocurrent response is Al-TCPP MOFs.

[0058] Experiments have found that Fig.12 As shown, when light pulses are applied under the same conditions, the current values ​​generated for the empty electrolytic cell and the bare AAM are very small and can be ignored.

[0059] The specific description above further illustrates the purpose, technical solutions and beneficial effects of the invention in detail. It should be understood that the above is only a specific embodiment of the present invention and is not intended to limit the scope of protection of 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. An artificial synaptic device of a light-controlled nanofluidic ion transistor, characterized in that: include: Nanofluid ion transistor, electrolyte solution, working electrode and reference electrode; the working electrode and reference electrode are placed in the electrolyte solution, serving as the source and drain of the nanofluid ion transistor respectively; the optical signal input changes the surface charge of the nanofluid ion transistor, thereby realizing synapse-like functions by light-regulated ion migration.

2. The artificial synaptic device of a light-controlled nanofluidic ion transistor as claimed in claim 1, characterized in that: The nanofluid ion transistor comprises: an anodic aluminum oxide film AAM and Al-TCPP MOFs in-situ grown in the pores of the AAM; the Al-TCPP MOFs are obtained by adding tetra-carboxyphenylporphyrin TCPP into the anodic aluminum oxide film AAM.

3. The artificial synaptic device of a light-controlled nanofluidic ion transistor as claimed in claim 2, characterized in that: The AAM has uniform double channels; thicknesses include 40 μm, 65 μm, 90 μm, and 120 μm; and a wide range of pore sizes, mainly 20-300 nm.

4. The artificial synaptic device of a light-controlled nanofluidic ion transistor as claimed in claim 1, characterized in that: The preparation method of the nanofluid ion transistor is as follows: (1) DMF and H2O are mixed in a volume ratio of 3:1 to obtain a mixed solvent; TCPP having a mass fraction of 0.26% to 0.39% is dissolved in the mixed solvent to form a mixture; ultrasonic treatment is performed to allow TCPP to fully enter the pores of AAM; and the mixture is transferred to a sealed bottle; (2) placing the sealed bottle in a microwave synthesizer and reacting at 140° C. for not less than 1 h to obtain an AAM-Al-TCPP MOFs membrane, i.e., MOFM; (3) The MOFM was washed three times with DMF and acetone respectively, and then dried at room temperature to remove excess solvent to obtain a nanofluidic ion transistor.

5. The artificial synaptic device of a light-controlled nanofluidic ion transistor as claimed in claim 1, characterized in that: The electrolyte solution is KCl solution.

6. The artificial synaptic device of a light-controlled nanofluidic ion transistor as claimed in claim 1, characterized in that: The working electrode and the reference electrode are both Ag / AgCl.

7. A method for measuring ion flow using the artificial synaptic device of the light-controlled nanofluidic ion transistor as claimed in claim 1, characterized in that: The input of optical signals enhances the negative charge on the surface of the nanofluidic ion transistor, causing an increase in the migration of carrier cations. When they reach the vicinity of the Ag / AgCl electrode, they will be neutralized by the electrons on the electrode, or the excess electrons will be drawn away by the electrode, causing a redox reaction and forming the flow of electrons, which manifests as a change in current.

Images