Samarium nickelate / molybdenum disulfide-based photoelectric memristor and preparation method and application thereof

Abstract

The invention relates to a samarium nickelate / molybdenum disulfide-based photoelectric memristor and a preparation method and application thereof. The photoelectric memristor integrates a photoelectric effect and a memristive effect, and comprises a bottom electrode substrate, a resistive function layer and a top electrode layer which are sequentially arranged from bottom to top, wherein the resistive function layer is composed of a molybdenum disulfide thin film and a samarium nickelate thin film, and the resistive function layer is of a heterojunction structure formed by the molybdenum disulfide thin film and the samarium nickelate thin film. Excitation signals of the device comprise direct-current voltage signals and light signals of a near ultraviolet band, and after illumination of the ultraviolet band is applied to the device, different light current responses can be generated under different light intensities or different irradiation time, so that effective sensing of the light of the ultraviolet band is achieved. When a direct-current voltage signal input to the photoelectric memristor is changed, the device has two different electrical states, namely a high resistance state and a low resistance state; and when the voltage signal is withdrawn, the device keeps the original electrical state unchanged, and has an obvious nonvolatile characteristic.

Description

Technical Field

[0001] The present invention belongs to the technical field of optoelectronic memristors, and particularly relates to an optoelectronic memristor based on samarium nickelate / molybdenum disulfide and a preparation method thereof. Background Art

[0002] A vision bionic system based on "sensing - storage - computing" integration can simulate the efficient information processing mechanism of biological vision (such as the "retinal preprocessing" of the human eye and the parallel computing of the brain), break through the energy efficiency bottleneck of the traditional vision system's perception, storage, and computing separation architecture, and achieve low - latency, high - parallel, and low - power processing of optical signals. It can greatly improve the real - time performance and environmental adaptability in fields such as autonomous driving, robot navigation, and edge intelligent monitoring. At the same time, it provides a solution closer to biological intelligence for brain - like computing and next - generation artificial intelligence hardware.

[0003] Memristors are considered an ideal choice for developing neuromorphic computing hardware units due to their advantages such as small size, high speed, low power consumption, and compatibility with complementary metal - oxide - semiconductor (CMOS) processes. A memristor usually consists of a "metal - insulator - metal" sandwich structure, where the top electrode, the middle insulating layer, and the bottom electrode respectively simulate the presynaptic membrane, the synaptic cleft, and the postsynaptic membrane. When an electrical stimulus is applied to the memristor, its special non - linear resistance conversion characteristics and adjustable characteristics can simulate the plasticity of biological synapses, providing the possibility for developing a bionic vision synaptic system.

[0004] However, traditional electrically modulated memristors are inefficient and consume high power, and cannot simulate the real perception of light by biological vision systems. In contrast, optoelectronic memristors can integrate light sensing and memristive storage characteristics, can regulate the resistance state through optical signals, and achieve direct perception, storage, and processing of optical information, providing a key technical path for bionic vision systems, low - power edge vision processing, and high - speed optical interconnection artificial intelligence chips, and promoting the development of machine vision, autonomous driving, and intelligent Internet of Things. In recent years, researchers at home and abroad have prepared different types of optoelectronic memristive devices with oxides, two - dimensional materials, etc. as functional layers, but there are still deficiencies in aspects such as light response speed and light / electrical signal coupling efficiency. Developing new sensing materials, developing new heterostructures, and using interface effects to achieve efficient light / electrical signal co - modulation is an effective strategy to solve the above problems. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides an optoelectronic memristor based on samarium nickelate / molybdenum disulfide, a preparation method thereof, and an application thereof to achieve co - modulation of light / electrical signals.

[0006] The technical solution of the present invention is as follows: A nickel samarium oxide / molybdenum disulfide-based optoelectronic memristor, which integrates the photoelectric effect and the memristive effect, includes a bottom electrode substrate, a resistive switching functional layer, and a top electrode layer sequentially arranged from bottom to top; Among them, the resistive switching functional layer is composed of a molybdenum disulfide thin film and a nickel samarium oxide thin film, and this resistive switching functional layer is a heterojunction structure formed by the two.

[0007] Preferably according to the present invention, the bottom electrode substrate is a 0.5% niobium-doped strontium titanate (Nb:SrTiO3) substrate, and its excellent conductivity helps to achieve good contact between the bottom electrode and the functional layer, ensuring the stability of the memristive performance and optoelectronic performance measurement of the device.

[0008] Preferably according to the present invention, the thickness of the molybdenum disulfide thin film is 80 - 120 nm.

[0009] More preferably, the thickness of the molybdenum disulfide thin film is 100 nm.

[0010] Preferably according to the present invention, the thickness of the nickel samarium oxide thin film is 70 - 90 nm.

[0011] More preferably, the thickness of the nickel samarium oxide thin film is 80 nm.

[0012] Preferably according to the present invention, the top electrode layer is a silver electrode. By utilizing its migration and reduction characteristics under voltage drive, conductive filaments connecting the upper and lower electrodes are generated, and the memristive effect of the device can be realized.

[0013] More preferably, the silver electrode is cylindrical, with a diameter of 80 - 100 μm, a height of 45 - 55 nm, and the number is 50 - 100.

[0014] Most preferably, the diameter of the silver electrode is 90 μm, the height is 50 nm, and the number is 90.

[0015] The preparation method of the above nickel samarium oxide / molybdenum disulfide-based optoelectronic memristor includes the following steps: Step 1: Pretreat the bottom electrode substrate; Step 2: First, use the hydrothermal synthesis method to synthesize a molybdenum disulfide thin film on the pretreated bottom electrode substrate, and then use the pulsed laser deposition technology to prepare a nickel samarium oxide thin film on the obtained molybdenum disulfide thin film to form a resistive switching functional layer composed of a molybdenum disulfide thin film and a nickel samarium oxide thin film; Step 3: Use the thermal evaporation technology to prepare a silver electrode on the top of the resistive switching functional layer obtained in Step 2 to obtain a nickel samarium oxide / molybdenum disulfide-based optoelectronic memristor.

[0016] Preferably according to the present invention, in step 1, the pretreatment is specifically as follows: in an ultrasonic machine, the bottom electrode substrate is ultrasonically cleaned with acetone, ethanol, and deionized water in sequence for 5 to 15 minutes, and after being dried with nitrogen, the pretreated bottom electrode substrate is obtained.

[0017] Preferably according to the present invention, in step 2, the specific process of synthesizing the molybdenum disulfide thin film is as follows: Sodium molybdate (MoNa2O4) and thioacetamide are dissolved in deionized water, stirred for 25 to 35 minutes and then left standing for 8 to 12 minutes to obtain a molybdenum disulfide precursor solution; then the molybdenum disulfide precursor solution is added to a hydrothermal reaction kettle, and the pretreated bottom electrode substrate is placed flat at the bottom of the hydrothermal reaction kettle, sealed and heated to 180 to 220 °C, reacted for 9.5 to 10.5 hours, naturally cooled to room temperature, washed and dried, and a bottom electrode substrate with a molybdenum disulfide thin film is obtained.

[0018] Further preferably, the molar ratio of sodium molybdate (MoNa2O4) to thioacetamide is (1 to 1.1):2; the molar volume ratio of sodium molybdate to deionized water is (1 to 1.1):15, unit: mmol / mL.

[0019] Most preferably, the molar ratio of sodium molybdate (MoNa2O4) to thioacetamide is 1:2; the molar volume ratio of sodium molybdate to deionized water is 1:15, unit: mmol / mL.

[0020] Preferably according to the present invention, in step 2, during the process of preparing the samarium nickelate thin film, the parameters of the pulsed laser deposition technology are as follows: the laser power is 80 to 120 W, the laser frequency is 3 to 6 Hz; oxygen is introduced during the deposition process, the oxygen gas pressure is 0.5 to 1.5 Pa, the temperature is maintained at 750 to 850 °C, and the deposition time is 25 to 35 minutes.

[0021] Further preferably, the parameters of the pulsed laser deposition technology are as follows: the laser power is 100 W, the laser frequency is 5 Hz; oxygen is introduced during the deposition process, the oxygen gas pressure is 1 Pa, the temperature is maintained at 800 °C, and the deposition time is 30 minutes.

[0022] Preferably according to the present invention, in step 3, the specific process of preparing the silver electrode is as follows: a metal mask plate with a circular hole is fixed on the upper surface of the resistive switching functional layer, and the top silver electrode is prepared by thermal evaporation technology under high vacuum, and the evaporation rate is 0.5 to 1.5 Å / s.

[0023] The above application of the samarium nickelate / molybdenum disulfide-based optoelectronic memristor in the field of artificial neural network visual synapses.

[0024] The technical features and beneficial effects of the present invention: 1. The present invention provides a photoelectric memristor based on samarium nickelate / molybdenum disulfide, which uses a novel heterostructure of samarium nickelate / molybdenum disulfide as the resistive switching functional layer to form a sandwich-structured artificial synaptic device with the silver electrode of the top electrode layer. The excitation signals of the device include a DC voltage signal and an optical signal in the near-ultraviolet band. After ultraviolet light in this band is applied, different photocurrent responses will be generated under different light intensities or different irradiation times, thereby realizing the effective perception of ultraviolet light. Moreover, when the DC voltage signal input to the photoelectric memristor is changed, the device has two different electrical states: a high-resistance state and a low-resistance state; when the voltage signal is removed, the device remains in its original electrical state unchanged, showing obvious non-volatile characteristics.

[0025] 2. Compared with existing photoelectric memristors, the samarium nickelate / molybdenum disulfide photoelectric memristor of the present invention, after introducing a samarium nickelate thin film, can not only achieve the memristive effect but also generate a significant photoelectric effect, and can be used in the field of visual perception of artificial neural networks.

[0026] 3. The photoelectric memristor based on samarium nickelate / molybdenum disulfide provided by the present invention produces different photocurrent effects under different light intensities and different irradiation times in the ultraviolet band, while having no obvious light response to light in other bands, which can effectively avoid the interference of natural light on stored data and has important application values in fields such as ultraviolet radiation dosimeters, fire warnings, and optical control switches in extreme ultraviolet lithography machines.

[0027] 4. The materials used in the photoelectric memristor based on samarium nickelate / molybdenum disulfide of the present invention are environmentally friendly and simple, the preparation process used is simple, the cost is low, the yield is high, it is suitable for large-scale production, and can be widely applied in fields such as information technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a schematic structural diagram of the photoelectric memristor based on samarium nickelate / molybdenum disulfide in Embodiment 1 of the present invention.

[0029] Figure 2 is the logarithmic current-voltage curve of the photoelectric memristor based on samarium nickelate / molybdenum disulfide in Embodiment 1 of the present invention.

[0030] Figure 3 is the current response curve of the photoelectric memristor based on samarium nickelate / molybdenum disulfide in Embodiment 1 of the present invention under different light intensities at a wavelength of 260 nm.

[0031] Figure 4 is the current response curve of the photoelectric memristor based on samarium nickelate / molybdenum disulfide in Embodiment 1 of the present invention under different irradiation times at a wavelength of 260 nm.

[0032] Figure 5 is the logarithmic current-voltage curve of the photoelectric memristor in Comparative Example 1.

[0033] Figure 6 It is the current response curve of the optoelectronic memristor of Comparative Example 1 under illumination at 265 nm for 10 seconds. Detailed implementation manners

[0034] To make the objectives, technical solutions and beneficial effects of the embodiments in the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present disclosure. Apparently, the described embodiments are some, but not all, of the embodiments of the present disclosure. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present disclosure without creative efforts shall fall within the protection scope of the present disclosure.

[0035] For the materials and reagents involved in the embodiments, unless otherwise specified, they are all ordinary commercially available products; for the experimental operations involved in the embodiments, unless otherwise specified, they are all carried out according to the conventional operations in the art; the current-voltage tests and optical tests described in the embodiments are all carried out according to the conventional methods in the art.

[0036] Example 1 As Figure 1 shown, an optoelectronic memristor based on samarium nickelate / molybdenum disulfide, the optoelectronic memristor integrates the photoelectric effect and the memristive effect, and includes a bottom electrode substrate, a resistive switching functional layer and a top electrode layer which are sequentially arranged from bottom to top, and the material is niobium-doped strontium titanate / molybdenum disulfide / samarium nickelate / silver electrode.

[0037] Among them, the resistive switching functional layer is composed of a molybdenum disulfide thin film and a samarium nickelate thin film, and the resistive switching functional layer is a heterojunction structure formed by the two; the thickness of the molybdenum disulfide thin film is 100 nm, and the thickness of the samarium nickelate thin film is 80 nm.

[0038] The bottom electrode substrate is a 0.5% niobium-doped strontium titanate (Nb:SrTiO3) substrate. Its excellent conductivity helps to achieve good contact between the bottom electrode and the functional layer, and ensures the stability of the measurement of the memristive performance and optoelectronic performance of the device.

[0039] The top electrode layer is a silver electrode, with a diameter of 90 μm, a height of 50 nm, and 90 in number. Utilizing its migration and reduction characteristics under voltage drive to generate conductive filaments connecting the upper and lower electrodes, the memristive effect of the device can be realized.

[0040] The preparation method of the above-mentioned optoelectronic memristor based on samarium nickelate / molybdenum disulfide includes the following steps: Step 1: In an ultrasonic machine, ultrasonically clean a 0.5% niobium-doped strontium titanate substrate with acetone, ethanol and deionized water in sequence for 10 minutes, and after drying with nitrogen, obtain a pretreated 0.5% niobium-doped strontium titanate substrate; Step 2: Dissolve 2 mmol of sodium molybdate and 4 mmol of thioacetamide in 30 ml of deionized water. After stirring for 30 minutes, let it stand for 10 minutes to obtain a molybdenum disulfide precursor solution. Then add the molybdenum disulfide precursor solution into a hydrothermal reaction kettle. Place the polished surface of the pre-treated 0.5% niobium-doped strontium titanate substrate face up flat at the bottom of the hydrothermal reaction kettle. Seal it and heat it to 200 °C, keep the temperature for reaction for 10 hours, naturally cool it to room temperature, wash it with deionized water and then dry it with nitrogen, and clean it repeatedly 3 times to obtain a dry and pure 0.5% niobium-doped strontium titanate substrate with a molybdenum disulfide thin film; Then, a samarium nickelate thin film is prepared on the obtained molybdenum disulfide thin film by pulsed laser deposition technology. The parameters of the pulsed laser deposition technology are: the laser power is 100 W, and the laser frequency is 5 Hz; oxygen is introduced during the deposition process, the oxygen gas pressure is 1 Pa, the temperature is maintained at 800 °C, and the deposition time is 30 minutes; Finally, a resistive switching functional layer composed of a molybdenum disulfide thin film and a samarium nickelate thin film is formed; Step 3: Fix a metal mask plate with a circular hole on the upper surface of the resistive switching functional layer, and prepare a top silver electrode by thermal evaporation technology under high vacuum. The evaporation rate is 1 Å / s to obtain a photo-electric memristor based on samarium nickelate / molybdenum disulfide.

[0041] Example 2 A photo-electric memristor based on samarium nickelate / molybdenum disulfide has a structure as shown in Example 1. The difference is that the thickness of the molybdenum disulfide thin film is 90 nm, and the thickness of the samarium nickelate thin film is 90 nm.

[0042] The preparation method of the above-mentioned photo-electric memristor based on samarium nickelate / molybdenum disulfide includes the following steps: Step 1: In an ultrasonic cleaner, ultrasonically clean the 0.5% niobium-doped strontium titanate substrate with acetone, ethanol and deionized water in sequence for 15 minutes. After drying it with nitrogen, obtain a pre-treated 0.5% niobium-doped strontium titanate substrate; Step 2: Dissolve 2 mmol of sodium molybdate and 4 mmol of thioacetamide in 30 ml of deionized water. After stirring for 25 minutes, let it stand for 15 minutes to obtain a molybdenum disulfide precursor solution. Then add the molybdenum disulfide precursor solution into a hydrothermal reaction kettle. Place the polished surface of the pre-treated 0.5% niobium-doped strontium titanate substrate face up flat at the bottom of the hydrothermal reaction kettle. Seal it and heat it to 210 °C, keep the temperature for reaction for 9 hours, naturally cool it to room temperature, wash it with deionized water and then dry it with nitrogen, and clean it repeatedly 3 times to obtain a dry and pure 0.5% niobium-doped strontium titanate substrate with a molybdenum disulfide thin film; Then, a samarium nickelate thin film was prepared on the obtained molybdenum disulfide thin film by pulsed laser deposition. The parameters of the pulsed laser deposition were as follows: the laser power was 95 W, and the laser frequency was 6 Hz; oxygen was introduced during the deposition process, the oxygen gas pressure was 1 Pa, the temperature was maintained at 800 °C, and the deposition time was 30 minutes; Finally, a resistive switching functional layer composed of a molybdenum disulfide thin film and a samarium nickelate thin film was formed; Step 3: Fix a metal mask template with a circular hole on the upper surface of the resistive switching functional layer, and prepare a top silver electrode by thermal evaporation under high vacuum. The evaporation rate was 0.8 Å / s, and a photoelectric memristor based on samarium nickelate / molybdenum disulfide was obtained.

[0043] Comparative Example 1 A photoelectric memristor has the same structure as that in Example 1, except that the resistive switching functional layer is a molybdenum disulfide thin film and does not contain a samarium nickelate thin film.

[0044] The preparation method of the photoelectric memristor in this comparative example was the same as that in Example 1, except that Step 2 was as follows: 2 mmol of sodium molybdate and 4 mmol of thioacetamide were dissolved in 30 ml of deionized water, stirred for 30 minutes and then left standing for 10 minutes to obtain a molybdenum disulfide precursor solution; then the molybdenum disulfide precursor solution was added to a hydrothermal reaction kettle, and the polished surface of the 0.5% niobium-doped strontium titanate substrate after pretreatment was placed face up flat at the bottom of the hydrothermal reaction kettle, sealed and heated to 200 °C, maintained for reaction for 10 hours, naturally cooled to room temperature, washed with deionized water and then dried with nitrogen, and cleaned repeatedly 3 times to obtain a dry and pure 0.5% niobium-doped strontium titanate substrate with a molybdenum disulfide thin film, using only the molybdenum disulfide thin film as the resistive switching functional layer.

[0045] Test Example 1. Electrical tests were performed on the photoelectric memristor described in Example 1. The test method was as follows: the bottom electrode substrate was grounded, the voltage was applied to the silver electrode, and its current-voltage characteristic curve from -15 V to +15 V was measured. The results were as Figure 2 shown; then the photoelectric memristor described in Example 1 was irradiated for 2 seconds at light intensities of 10, 20, 30, 40, and 50 μW / cm 2 , and its current response curve was measured. The results were as Figure 3 shown; finally, the photoelectric memristor described in Example 1 was continuously irradiated for 1, 3, 5, 10, and 15 seconds under ultraviolet light at 260 nm and 20 μW / cm 2 , and its current response curve was measured. The results were as Figure 4 shown.

[0046] From Figure 2It can be seen that after applying a cyclic voltage of ±15V to the optoelectronic memristor based on samarium nickelate / molybdenum disulfide described in Example 1, the device has two different electrical states, namely, a high-resistance state and a low-resistance state. Moreover, when the voltage signal is withdrawn, the device maintains its original electrical state unchanged, exhibiting an obvious non-volatile characteristic. Also, after 20 cycles, the IV curve of the device remains unchanged, demonstrating the stability of the device under long-term operation.

[0047] It is known from Figure 3 that when the optoelectronic memristor based on samarium nickelate / molybdenum disulfide described in Example 1 is irradiated for 2 seconds at light intensities of 10, 20, 30, 40, and 50 μW / cm 2 , photocurrents of 10.0, 12.3, 13.8, 15.1, and 17.9 nA can be generated respectively. This indicates that the optoelectronic memristor based on samarium nickelate / molybdenum disulfide of the present invention can effectively respond to light of different intensities and is sensitive to received signals.

[0048] It is known from Figure 4 that when the optoelectronic memristor based on samarium nickelate / molybdenum disulfide described in Example 1 is irradiated with ultraviolet light of 260 nm and 20 μW / cm 2 for 1, 3, 5, 10, and 15 seconds, photocurrents of 10.0, 12.3, 13.8, 15.1, and 17.9 nA can be generated respectively. This shows that the optoelectronic memristor based on samarium nickelate / molybdenum disulfide of the present invention can have excellent responses under different illumination times, and the response of the optoelectronic memristor based on samarium nickelate / molybdenum disulfide increases with the increase of the illumination time.

[0049] 2. Electrical tests were carried out on the memristor based on molybdenum disulfide described in Comparative Example 1. The test method was as follows: the bottom electrode substrate was grounded, and the voltage was applied to the silver electrode to measure its current-voltage characteristic curve from -5V to +3V. The results are as Figure 5 shown; then the memristor based on molybdenum disulfide described in Comparative Example 1 was continuously irradiated with ultraviolet light of 265 nm and 5.5 mW / cm 2 for 10 seconds, and its current response curve was measured. The results are as Figure 6 shown.

[0050] It is known from Figure 5 that although the optoelectronic memristor described in Comparative Example 1 has two different electrical states, namely, a high-resistance state and a low-resistance state, when a cyclic voltage from +3V to -5V is applied, and when the voltage signal is withdrawn, the device maintains its original electrical state unchanged, showing an obvious non-volatile characteristic. However, compared with Example 1, after 10 cycle tests on the optoelectronic memristor described in Comparative Example 1, an obvious change occurred in the IV curve of the device, indicating that the optoelectronic memristor described in Comparative Example 1 has poor stability under long-term operation.

[0051] It is known from Figure 6It can be seen that the optoelectronic memristor described in Comparative Example 1 generated a photocurrent of about 8 nA under the irradiation of near-ultraviolet light at 265 nm and 5.5 mW / cm 2 for 10 s, and the relaxation time of the photocurrent decay was much longer than the rise time of the photocurrent, with the decay relaxation time exceeding 60 s. The optoelectronic memristor based on samarium nickelate / molybdenum disulfide described in Example 1 generated a photocurrent response of 10 nA in 2 s, and the relaxation time of the photocurrent decay was only 6 s, far lower than that of Example 1. This shows that the optoelectronic memristor based on samarium nickelate / molybdenum disulfide described in Example 1 can sense higher-frequency optical signals, has a faster sensing speed, is more sensitive, and is more suitable for application in the field of artificial neural network visual perception.

[0052] The above-described embodiments are only exemplary descriptions of the present disclosure, and do not limit the scope of the present disclosure. Without departing from the design spirit of the present disclosure, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present disclosure shall fall within the protection scope determined by the present disclosure.

Claims

1. A nickel samarium oxide / molybdenum disulfide-based optoelectronic memristor, characterized in that, It includes a bottom electrode substrate, a resistive switching functional layer, and a top electrode layer which are arranged successively from bottom to top; Among them, the resistive switching functional layer is composed of a molybdenum disulfide thin film and a samarium nickelate thin film, and the resistive switching functional layer is a heterojunction structure formed by the two.

2. The optoelectronic memristor according to claim 1, wherein The bottom electrode substrate is a 0.5% niobium-doped strontium titanate substrate, the thickness of the molybdenum disulfide thin film is 80 - 120 nm, and the thickness of the samarium nickelate thin film is 70 - 90 nm.

3. The optoelectronic memristor according to claim 2, characterized in that, The thickness of the molybdenum disulfide thin film is 100 nm, and the thickness of the samarium nickelate thin film is 80 nm.

4. The optoelectronic memristor according to claim 1, wherein The top electrode layer is a cylindrical silver electrode, with a diameter of 80 - 100 μm, a height of 45 - 55 nm, and the number is 50 - 100.

5. The optoelectronic memristor according to claim 4, wherein The diameter of the silver electrode is 90 μm, the height is 50 nm, and the number is 90.

6. The method for preparing a nickel samarium oxide / molybdenum disulfide-based optoelectronic memristor according to any one of claims 1 to 5, characterized in that, It includes the following steps: Step 1: Pretreat the bottom electrode substrate; Step 2: First, use the hydrothermal synthesis method to synthesize a molybdenum disulfide thin film on the pretreated bottom electrode substrate, and then use the pulsed laser deposition technique to prepare a samarium nickelate thin film on the obtained molybdenum disulfide thin film to form a resistive switching functional layer composed of a molybdenum disulfide thin film and a samarium nickelate thin film; Step 3: Use the thermal evaporation technique to prepare a silver electrode on the top of the resistive switching functional layer obtained in Step 2 to obtain a photoelectric memristor based on samarium nickelate / molybdenum disulfide.

7. The preparation method according to claim 6, characterized in that, In Step 2, the specific process of synthesizing the molybdenum disulfide thin film is as follows: Dissolve sodium molybdate and thioacetamide in deionized water, stir for 25 - 35 minutes and then stand for 8 - 12 minutes to obtain a molybdenum disulfide precursor solution; then add the molybdenum disulfide precursor solution into a hydrothermal reaction kettle, and then place the pretreated bottom electrode substrate flat on the bottom of the hydrothermal reaction kettle, seal it and heat it to 180 - 220 °C, react for 9.5 - 10.5 hours, naturally cool to room temperature, wash and dry to obtain a bottom electrode substrate with a molybdenum disulfide thin film; Further preferably, the molar ratio of sodium molybdate to thioacetamide is (1 - 1.1):2; the molar volume ratio of sodium molybdate to deionized water is (1 - 1.1):15, unit: mmol / mL; Most preferably, the molar ratio of sodium molybdate to thioacetamide is 1:2; the molar volume ratio of sodium molybdate to deionized water is 1:15, unit: mmol / mL.

8. The preparation method according to claim 6, characterized in that, In Step 2, during the process of preparing the samarium nickelate thin film, the parameters of the pulsed laser deposition technique are: the laser power is 80 - 120 W, the laser frequency is 3 - 6 Hz; oxygen is introduced during the deposition process, the oxygen gas pressure is 0.5 - 1.5 Pa, the temperature is kept at 750 - 850 °C, and the deposition time is 25 - 35 minutes; Further preferably, the parameters of the pulsed laser deposition technique are: the laser power is 100 W, the laser frequency is 5 Hz; oxygen is introduced during the deposition process, the oxygen gas pressure is 1 Pa, the temperature is kept at 800 °C, and the deposition time is 30 minutes.

9. The preparation method according to claim 6, characterized in that, In Step 3, the specific process of preparing the silver electrode is: Fix a metal mask plate with a circular hole on the upper surface of the resistive switching functional layer, and use the thermal evaporation technique to prepare a top silver electrode under high vacuum, and the evaporation rate is 0.5 - 1.5 Å / s.

10. Use of the nickel samarium oxide / molybdenum disulfide-based optoelectronic memristor according to any one of claims 1 to 5 in the field of artificial neural network vision synapses.

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