Inorganic-organic heterojunction-based visual adaptive optoelectronic memristor and preparation method thereof

Abstract

The application provides a visual adaptive optoelectronic memristor based on inorganic-organic heterojunction and a preparation method thereof, and belongs to the technical field of optoelectronic memristors. The memristor adopts TiO2 and PEDOT:PSS to construct an inorganic-organic planar heterojunction, utilizes the characteristic that the PEDOT:PSS film spontaneously adsorbs water molecules, and forms a unique light self-adaptive mechanism of the memristor through the adsorption and desorption processes of the water molecules, so that the light self-adaptive capability of the device is realized. The device can work under a single fixed pulse voltage. When the environmental light intensity changes, the device can completely rely on its internal physical mechanism to autonomously adjust the conductance state, realize the complete adaptive response from signal enhancement to inhibition, realize the complete adaptive response from signal enhancement to intelligent inhibition, and effectively simulate the light-dark adaptation process of biological vision.

Description

Technical Field

[0001] This invention belongs to the field of optoelectronic memristor technology, specifically relating to a visually adaptive optoelectronic memristor based on an inorganic-organic heterojunction and its fabrication method. Background Technology

[0002] Visual perception is one of the key abilities of living organisms (especially humans) to acquire information from the external environment. Studies have shown that more than 80% of external information received by the human body is through the visual system. The human eye possesses remarkable light sensitivity and dynamic adaptability, with a light detection dynamic range exceeding 160 dB, enabling it to efficiently process visual information under a wide range of illumination conditions, from low light to high light. This excellent adaptive mechanism allows humans to maintain clear visual perception even in complex lighting scenarios such as watching movies in a dark theater or driving in bright light.

[0003] In cutting-edge fields such as intelligent manufacturing, autonomous driving, and medical imaging, developing biomimetic artificial vision sensing systems has become a significant trend. Traditional photodetectors primarily focus on improving sensitivity or expanding operating wavelengths, and their performance has approached or even surpassed the limits of the human eye. However, these devices typically have a fixed photoresponsivity and cannot dynamically adjust their sensing characteristics according to ambient lighting conditions, leading to problems such as image distortion and decreased recognition accuracy under changing light conditions. In recent years, the academic community has gradually recognized that adaptability is one of the core indicators for building efficient artificial vision systems.

[0004] Neuromorphic devices, such as memristors and transistors, are considered key carriers for realizing photoadaptive behavior. Existing research simulates photoadaptation by introducing charge / ion hysteresis response or external modulation (such as gate voltage) into the device, but still faces challenges such as complex fabrication processes, reliance on external biases, poor process repeatability, or the need for back-end algorithm compensation. For example, patent CN120916569A discloses an organic semiconductor heterojunction photoadaptive memristor and its fabrication method, which integrates two biological adaptive functions (desensitization behavior and retinal adaptive function) on a single neuromorphic device. It can switch adaptive modes according to the stimulus type and time-sharing trigger mechanism to support multimodal perception and adaptive information processing in dynamic environments, but this method is difficult to effectively distinguish and adapt to high dynamic range illumination conditions. CN119212410A proposes a stretchable broadband photoadaptive synaptic transistor and its fabrication method, which has excellent synaptic behavior simulation function, broadband biomimetic visual adaptive function, and imaging effect. However, its visual adaptation function mainly relies on the regulation of the external gate voltage. This non-autonomous regulation mechanism limits the application potential of the device in low-power, high-autonomy scenarios such as edge computing.

[0005] In conclusion, developing a neuromorphic vision device that can autonomously adapt to complex lighting environments and possesses both high precision and low processing redundancy has significant scientific and application value. Summary of the Invention

[0006] To address the problems existing in the background technology, the purpose of this invention is to provide a visually adaptive optoelectronic memristor based on an inorganic-organic heterojunction and its fabrication method. This memristor uses TiO2 and PEDOT:PSS to construct an inorganic-organic planar heterojunction. Utilizing the spontaneous adsorption of water molecules by the PEDOT:PSS thin film, the adsorption and desorption process of water molecules constitutes a unique light-adaptive mechanism of the memristor, thereby realizing the light-adaptive capability of the device.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows:

[0008] A visually adaptive opto-memristor based on an inorganic-organic heterojunction consists of a bottom electrode, a TiO2 thin film, a PEDOT:PSS thin film, and a top electrode, from bottom to top.

[0009] The bottom electrode is a transparent conductive electrode;

[0010] TiO2 thin film and PEDOT:PSS thin film constitute an inorganic-organic planar heterostructure;

[0011] The top electrode is a periodically arrayed metal composite electrode.

[0012] Furthermore, the transparent conductive electrode is preferably FTO conductive glass; the metal composite electrode is a Ti / Au metal composite electrode with a thickness of 80-100 nm.

[0013] Furthermore, the thickness of the TiO2 film is 70-80 nm, and the thickness of the PEDOT:PSS film is 30-40 nm; the mass ratio of PEDOT to PSS during the preparation of the PEDOT:PSS film is 1:2.5.

[0014] Furthermore, the adaptive rate of the device can be adjusted by regulating the device's operating voltage.

[0015] Furthermore, the adaptive rate of the visually adaptive photomemristor can be adjusted by irradiating it with ultraviolet light.

[0016] A method for fabricating a visually adaptive opto-memristor based on an inorganic-organic heterojunction includes the following steps:

[0017] Step 1. Clean the bottom electrode and treat it with plasma;

[0018] Step 2. Prepare the titanium ion precursor solution. The specific process is as follows:

[0019] Diethanolamine, tetrabutyl titanate and anhydrous ethanol were mixed and stirred. Then, a mixture of ultrapure water and anhydrous ethanol was added and stirred again to obtain a titanium dioxide sol-gel system. Finally, the system was allowed to stand at room temperature for a period of time to prepare the desired titanium ion precursor solution.

[0020] Step 3. The titanium ion precursor solution from Step 2 is spin-coated onto the substrate surface obtained in Step 1. After spin-coating, thermal annealing is performed. Anatase TiO2 film can be prepared on the substrate surface after annealing. Then, plasma treatment is performed to restore the surface hydrophilicity.

[0021] Step 4: PEDOT:PSS is spin-coated onto the TiO2 film obtained in Step 3 using a solution spin-coating method. After spin-coating, a thermal annealing treatment is performed to obtain a PEDOT:PSS film on the TiO2 film surface after annealing.

[0022] Step 5. A patterned electrode layer is prepared on the PEDOT:PSS surface using photolithography and sputtering. Then, the photoresist is removed with acetone. Subsequently, the film surface is cleaned with anhydrous ethanol and deionized water in sequence. This allows the relatively hydrophobic PEDOT:PSS film, after high-temperature annealing, to re-adsorb and lock in a certain amount of water molecules, thus obtaining the desired visually adaptive photomemristor.

[0023] Furthermore, the thermal annealing conditions in step 3 are as follows: annealing at 400~500℃ for 30 minutes to 2 hours in an air atmosphere to ensure the acquisition of a pure anatase phase film.

[0024] Furthermore, the heat annealing conditions in step 4 are: annealing at 120~140℃ in a vacuum environment for 60~90 minutes.

[0025] Furthermore, in step 5, during the photolithography development process, the PEDOT:PSS film will swell slightly. After soaking in the developer, the device surface needs to be dried immediately and then baked to prevent excessive swelling of the PEDOT:PSS film from damaging the electrode pattern.

[0026] The mechanism of this invention is as follows:

[0027] This invention provides a light-adaptive memristor inspired by the working mechanism of the human eye. The abundant hydrophilic groups (such as sulfonic acid groups) on the surface of the PEDOT:PSS thin film can spontaneously adsorb water molecules, forming an adsorbed water layer on the film surface. In darkness or continuous low light environments, this adsorbed water layer optimizes charge transport, resulting in high conductivity. The current gradually increases with illumination time, accurately simulating the dark adaptation process of the human eye as its visual sensitivity gradually increases in dark environments. In strong light environments, the device current rises rapidly in the initial stage due to the injection of a large number of photogenerated charge carriers. Subsequently, continuous illumination and the resulting thermal effect cause the adsorbed water molecules to desorb due to sufficient kinetic energy, leading to a gradual decrease in film conductivity. The overall current exhibits a dynamic response of first rising and then falling, eventually even falling below the initial state. This "excitation-inhibition" characteristic based on the reversible change of surface adsorbed water is highly analogous to the light adaptation protection mechanism of the human eye, which autonomously reduces visual sensitivity through physiological regulation to achieve comfortable perception after moving from darkness to light. This characteristic enables it to dynamically enhance weak light signals while effectively suppressing high-intensity light stimulation, thereby significantly mitigating interference caused by extreme brightness changes in complex environments and improving the system's recognition accuracy under harsh lighting conditions. Therefore, this invention utilizes the adsorption and desorption processes of water molecules to construct a unique light-adaptive mechanism for the device, enabling it to successfully simulate key visual adaptation behaviors under a fixed pulse voltage: under moderate lighting conditions, its adaptation process is similar to that of the human eye, requiring almost no adjustment; when the environment abruptly changes from dim to bright light, the device exhibits a unique dynamic response—the current first rises rapidly to a peak, then quickly falls back to the baseline level, and finally falls below the dark current level under high light intensity.

[0028] In addition, after preparing the electrode pattern, this invention introduces anhydrous ethanol and deionized water to clean the film surface, allowing the PEDOT:PSS film after high-temperature annealing to rehydrate, restoring its hydrophilicity and introducing water molecules necessary for the adaptive mechanism. This process cleverly resolves the contradiction between the hydrophobicity of the organic functional layer after treatment and the functional requirements of the device, and is the core of activating and stabilizing the device's intelligent response.

[0029] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0030] The proposed visually adaptive photoresistor based on an inorganic-organic heterojunction possesses adjustable visual adaptability. Unlike existing technologies that often require adjusting the operating voltage according to different light intensities, this device can operate under a single, fixed pulse voltage. When ambient light intensity changes, the device can autonomously adjust its conductance state entirely through its internal physical mechanisms, achieving a complete adaptive response from signal enhancement to suppression, and vice versa, effectively simulating the light-dark adaptation process of biological vision. Furthermore, this device retains the ability to flexibly control the adaptive rate by adjusting the operating voltage, allowing for optimized matching according to the needs of different application scenarios. These characteristics greatly simplify the design of peripheral driving and control circuits, significantly reducing the overall system complexity and power consumption, making it closer to the simple and efficient working principles of biological systems, and possessing significant application value in neuromorphic vision and low-power sensing systems. Attached Figure Description

[0031] Figure 1 This is a structural diagram of the visually adaptive opto-memristor based on an inorganic-organic heterojunction according to the present invention.

[0032] Figure 2 This is a schematic diagram of the fabrication process of the visually adaptive photomemristor of the present invention.

[0033] Figure 3 The normalized current-pulse number scatter plot is shown for the memristor prepared in Example 1 under a fixed pulse voltage and different ultraviolet light intensities.

[0034] Figure 4 The normalized current-pulse count scatter plot of the memristor prepared in Example 1 under ultraviolet light irradiation and different bias voltages.

[0035] Figure 5 The current response curve of the memristor prepared in Example 1 after applying ultraviolet light during current-time scan testing.

[0036] Figure 6 The graph shows the change in the intensity of the adsorbed water peak as a function of temperature in in-situ infrared testing of the memristor prepared in Example 1.

[0037] Figure 7 The thermogravimetric analysis (TGA) results of TiO2 / PEDOT:PSS powder peeled off the surface of the memristor prepared in Example 1 are shown in the figure.

[0038] Figure 8 The image shows the photoelectric test results of the memristor prepared in Example 1 at different temperatures.

[0039] Figure 9The image shows the photoelectric test results of the memristor prepared in Example 1 after drying and cooling at 120°C and after being soaked in water and dried again.

[0040] Figure 10 The current-pulse count scatter plots of the memristors prepared in Example 1 and Comparative Example 1 under a fixed pulse voltage and the same ultraviolet light intensity are shown. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings.

[0042] A visually adaptive opto-memristor based on an inorganic-organic heterojunction is shown in the schematic diagram below. Figure 1 As shown, from bottom to top, the structure consists of a bottom electrode, a TiO2 thin film, a PEDOT:PSS thin film, and a top electrode. The bottom electrode is an FTO transparent conductive electrode. The TiO2 thin film and the PEDOT:PSS thin film form an inorganic-organic planar heterojunction. The top electrode is a periodically arrayed Ti / Au metal composite electrode. The transparent conductive electrode is preferably an FTO conductive glass. The metal composite electrode is a Ti / Au metal composite electrode with a thickness of 80-100 nm.

[0043] Example 1

[0044] A method for fabricating a visually adaptive opto-memristor based on an inorganic-organic heterojunction is illustrated in the flowchart below. Figure 2 As shown, it includes the following steps:

[0045] Step 1. The glass substrate with the FTO bottom electrode was ultrasonically cleaned sequentially with acetone, ethanol and deionized water. The ultrasonic cleaner was set to 100 kHz, 100% power and 15 minutes. After cleaning, the surface moisture of the bottom electrode was blown off with nitrogen and then placed in a plasma cleaner for 10 minutes to enhance surface cleanliness and improve the adhesion of subsequent thin film deposition.

[0046] Step 2. Prepare the titanium ion precursor solution. The specific process is as follows:

[0047] 2.45 mL of diethanolamine, 8.5 mL of tetrabutyl titanate and 33.6 mL of anhydrous ethanol were mixed and stirred for 2 hours. Then, 0.45 mL of ultrapure water and 5 mL of anhydrous ethanol were added and stirred for another 2 hours to obtain titanium dioxide sol gel. Finally, the mixture was allowed to stand at room temperature for 24 hours to prepare the desired titanium ion precursor solution.

[0048] Step 3. The titanium ion precursor solution from Step 2 was spin-coated onto the FTO bottom electrode surface obtained in Step 1 using a spin-coating method. The spin-coating parameters were set as follows: acceleration 10000 rpm / s, rotation speed 3000 r / min, and duration 30 seconds. After spin-coating, the sample was placed in a ceramic boat and then placed in a tube furnace heated to 450℃. It was annealed in air for 1 hour to form a TiO2 film with a thickness of approximately 80 nm. Then, plasma treatment was performed to restore the surface hydrophilicity.

[0049] Step 4: Spin-coat PEDOT:PSS onto the TiO2 film obtained in Step 3 using the solution spin-coating method. The spin-coating process parameters are the same as those in Step 3. After spin-coating, place the sample in a ceramic boat and put it into a vacuum drying oven heated to 130°C for heat annealing for 1 hour. After annealing, a PEDOT:PSS film with a thickness of about 30nm is obtained on the TiO2 film surface.

[0050] Step 5. A patterned electrode layer is fabricated on the PEDOT:PSS surface using a photolithography and sputtering process. The specific process is as follows:

[0051] First, AZ5214 photoresist is spin-coated onto the PEDOT:PSS thin film using the following spin-coating parameters: 1000 rpm for 10 seconds, followed by 3000 rpm for 30 seconds. Then, the film is pre-baked at 100°C for 60 seconds. Next, a photomask is used for UV exposure for 4 seconds, followed by baking at 120°C for 90 seconds and then general exposure for 40 seconds. Subsequently, the sample is immersed sequentially in developer and deionized water for 40–45 seconds each to complete development. After development, immediate air blowing and drying are required to prevent swelling of the PEDOT:PSS organic thin film and subsequent pattern destruction, thus forming a top electrode pattern mask on the surface of the PEDOT:PSS organic thin film.

[0052] Subsequently, Ti and Au were sequentially deposited using magnetron sputtering to form a Ti / Au composite metal electrode with a thickness of 80 nm. Finally, ultrasonic cleaning was performed sequentially using acetone, anhydrous ethanol, and deionized water to remove photoresist and process residues, resulting in a patterned top electrode. The electrode units are circular with a diameter of 500 μm, and the top electrode is formed by a periodic array of these electrode units. Simultaneously, this cleaning process caused the relatively hydrophobic PEDOT:PSS film, after high-temperature annealing, to re-adsorb and lock in a certain amount of water molecules. These water molecules will directly participate in and regulate the dynamic changes in the device's conductivity during subsequent operation, which is a key step in realizing its visual adaptive function.

[0053] The photoresist prepared in Example 1 was characterized using a Keysight B1500 semiconductor parameter analyzer. During testing, the bottom electrode (FTO) was connected to the negative terminal of the power supply, and the top electrode (Ti / Au) was connected to the positive terminal. The photostimulation signal was provided by a commercial LED light source, using ultraviolet light with a center wavelength of 365 nm, and was directed perpendicularly to the device surface.

[0054] The normalized current-pulse number scatter plots under different ultraviolet light intensities with a fixed pulse voltage are shown below. Figure 3 As shown: While applying a fixed 1.5V continuous electrical pulse, different intensities (0 to 320mW / cm) are used as supplementary pulses. 2 Continuous exposure to ultraviolet light. It can be observed that its response dynamics exhibit a precise biomimetic correspondence with the human eye's light-dark adaptation process: in low-light environments, such as light intensity of 0-200 mW / cm²... 2 The device's peak current response continuously increases, simulating the "dark adaptation" process where the human eye gradually increases retinal sensitivity in dark environments to enhance the capture of weak signals; while in high-light environments, such as with a light intensity of 320mW / cm²... 2 The device response exhibits a characteristic of first rapidly increasing to a peak value, then gradually decreasing and eventually stabilizing at a lower level. This dynamic of "excitation followed by inhibition" perfectly corresponds to the "light adaptation" protection mechanism of the human eye when it suddenly enters a bright place from a dark place, by constricting the pupil and regulating nerve signals to avoid overload.

[0055] The normalized current-pulse count scatter plot under different bias voltages under ultraviolet light irradiation is shown below. Figure 4 As shown, with a fixed ultraviolet light intensity of 320 mW / cm², 2 Under certain conditions, changing the applied pulse voltage (1.1-1.7V) reveals a clear voltage threshold dependence in the device response: at 1.1V, the current is not completely suppressed; however, at higher voltages (1.3V-1.7V), it exhibits robust adaptive behavior, with the adaptation rate increasing with voltage. Specifically, the higher the voltage, the earlier the inflection point of adaptation occurs, and the lower the current after adaptation. The key to this phenomenon is that the instantaneous current is small in pulse mode, and the Joule heat generated at a 1.1V pulse is insufficient to fully drive the desorption of water vapor molecules in the organic layer of the device. However, once the voltage exceeds the threshold, the adaptive rate can be effectively controlled, demonstrating good external adjustability and robustness. Therefore, in applications, the device's adaptive rate can be changed by adjusting the operating voltage according to the scenario requirements, flexibly adapting to different environments. This characteristic, while ensuring core biomimetic functionality, greatly simplifies the drive circuit design and reduces system complexity and power consumption.

[0056] Figure 5To visually adapt the current response curve of the opto-memristor after applying ultraviolet light during current-time scanning testing under continuous voltage, a light source of 320 mW / cm² was applied. 2 When stimulated by ultraviolet light, the current response of all devices exhibits a typical adaptive trend of first rising rapidly and then gradually decreasing, which is highly consistent with the process by which the human eye quickly adjusts to a comfortable visual steady state under strong light. Figure 4 In contrast to the inability to fully adapt at low voltages, continuous voltage can generate a steady-state current significantly higher than that of pulsed voltage, thereby inducing stronger Joule heating, enabling the device to desorb water vapor molecules at all voltages and achieve self-adaptation.

[0057] Figure 6 The figure shows the change in the intensity of the adsorbed water peak with temperature in the in-situ infrared spectroscopy of powder detached from the device surface. As can be seen from the figure, the absorption peak intensity of the adsorbed water peak in the range of 3400-3800 cm⁻¹ gradually weakens with increasing temperature. This spectral band corresponds to the characteristic vibration of adsorbed water, indicating that the adsorbed water on the device surface gradually desorbs with increasing temperature.

[0058] Figure 7 The thermogravimetric analysis (TGA) results are shown for the TiO2 / PEDOT:PSS powder sloughed off the device surface. The figure shows that the sample mass decreased by 4.38% below 100℃, with a higher mass loss rate in the initial heating stage. This indicates that the device can rapidly dehydrate at low temperatures, which directly corresponds to the adaptive behavior of the device under strong ultraviolet light irradiation: the Joule heating or photothermal effect generated during operation raises the temperature of the active layer, triggering rapid desorption of adsorbed water, thereby altering the carrier transport path and leading to a decrease in macroscopic conductivity.

[0059] Figure 8 Applying a 1.5V pulse voltage and a continuous 320mW / cm² voltage to the device at different temperatures 2 The current-time curves under ultraviolet light irradiation are shown. Except at room temperature, no adaptive phenomenon was observed after heating. This is related to the rapid dehydration at low temperatures in the previous thermogravimetric test: under constant temperature conditions, a large amount of water molecules adsorbed on the device surface had already desorbed before the test began. At this time, the additional thermal stimulation introduced by light irradiation had little effect and therefore could not trigger a complete adaptive dynamic process.

[0060] Figure 9 The reversibility functional experiment further verified the core role of water molecules in the adaptive mechanism: after the device was baked at 120℃ and cooled, its photoadaptive properties were completely lost; however, after immersion in water to restore the surface adsorbed water, this property was fully restored. Figure 8 The results show that the conductivity of the device is essentially the same at 120℃ and after cooling to room temperature, indicating that temperature itself is not a key parameter that directly determines the function. Figure 6Dynamic evidence of desorption of adsorbed water with increasing temperature in in-situ infrared spectroscopy, and Figure 7 The corresponding mass loss in thermogravimetric analysis clearly indicates that heating causes the device to lose water, thus impairing its adaptive ability; however, replenishing water restores its function. This set of experiments confirms from both positive and negative perspectives that the reversible adsorption and desorption of water molecules in the device is the fundamental physical basis for regulating its biomimetic adaptive behavior.

[0061] Comparative Example 1

[0062] Following the preparation process of Example 1, after preparing the PEDOT:PSS thin film, a metal cutout mask was used to cover the sample surface, and then the metal electrode was prepared by magnetron sputtering instead of photolithography as used in Example 1.

[0063] The device prepared in this comparative example was subjected to a 320mW / cm² test when a continuous 1.5V electrical pulse was applied. 2 Ultraviolet light irradiation, such as Figure 10 As shown, the device current exhibits a continuous increase and lacks adaptive characteristics.

[0064] In summary, the photoelectric memristor fabricated in this invention can autonomously complete a full adaptive cycle from light sensing to conductance self-adjustment under a fixed pulse voltage without adjustment, eliminating the need for complex external circuitry. This simulates the fundamental, passive adaptive instinct of biological visual systems. More importantly, by simply adjusting the single electrical parameter—the applied pulse voltage—the rate of the device's adaptive process can be precisely and linearly controlled, flexibly adapting to different environmental conditions, from low to high light. This device can intelligently adjust its response intensity according to external lighting conditions, not only helping to reduce system power consumption in complex lighting environments but also providing a reliable hardware solution for low-power, high-performance applications in fields such as intelligent vision sensors, autonomous driving, and intelligent monitoring.

[0065] The above description is merely a specific embodiment of the present invention. Any feature disclosed in this specification may be replaced by other equivalent or similar features unless otherwise specified. All disclosed features, or steps in all methods or processes, may be combined in any way except for mutually exclusive features and / or steps.

Claims

1. A visually adaptive opto-memristor based on an inorganic-organic heterojunction, characterized in that, The visually adaptive opto-memristor consists of a bottom electrode, a TiO2 thin film, a PEDOT:PSS thin film, and a top electrode, from bottom to top. The bottom electrode is a transparent conductive electrode; TiO2 thin film and PEDOT:PSS thin film constitute an inorganic-organic planar heterostructure; The top electrode is a periodically arrayed metal composite electrode.

2. The visually adaptive opto-memristor based on an inorganic-organic heterojunction as described in claim 1, characterized in that, The transparent conductive electrode is made of FTO conductive glass; the metal composite electrode is made of Ti / Au metal composite electrode with a thickness of 80-100 nm.

3. The visually adaptive opto-memristor based on an inorganic-organic heterojunction as described in claim 1, characterized in that, The thickness of the TiO2 film is 70-80 nm, and the thickness of the PEDOT:PSS film is 30-40 nm.

4. The visually adaptive opto-memristor based on an inorganic-organic heterojunction as described in claim 1, characterized in that, The mass ratio of PEDOT to PSS in the preparation of PEDOT:PSS films is 1:2.

5.

5. The visually adaptive opto-memristor based on an inorganic-organic heterojunction as described in claim 1, characterized in that, The adaptive rate of the device is adjusted by regulating its operating voltage.

6. The visually adaptive opto-memristor based on an inorganic-organic heterojunction as described in claim 1, characterized in that, The adaptive rate of a visually adaptive opto-memristor is adjusted by irradiating it with ultraviolet light.

7. A method for fabricating a visually adaptive opto-memristor based on an inorganic-organic heterojunction, characterized in that, Includes the following steps: Step 1. Clean the bottom electrode and treat it with plasma; Step 2. Prepare the titanium ion precursor solution. The specific process is as follows: Diethanolamine, tetrabutyl titanate and anhydrous ethanol were mixed and stirred. Then, a mixture of ultrapure water and anhydrous ethanol was added and stirred again to obtain a titanium dioxide sol-gel system. Finally, the system was allowed to stand at room temperature for a period of time to prepare the desired titanium ion precursor solution. Step 3. The titanium ion precursor solution from Step 2 is spin-coated onto the substrate surface obtained in Step 1. After spin-coating, thermal annealing is performed to prepare anatase TiO2 film on the substrate surface. Then, plasma treatment is performed to restore the surface hydrophilicity. Step 4: PEDOT:PSS is spin-coated onto the TiO2 film obtained in Step 3 using a solution spin-coating method. After spin-coating, a thermal annealing treatment is performed to obtain a PEDOT:PSS film on the TiO2 film surface after annealing. Step 5. A patterned electrode layer is prepared on the PEDOT:PSS surface using photolithography and sputtering. Then, the photoresist is removed with acetone. Subsequently, the film surface is cleaned with anhydrous ethanol and deionized water in sequence. This allows the relatively hydrophobic PEDOT:PSS film, after high-temperature annealing, to re-adsorb and lock in a certain amount of water molecules, thus obtaining the desired visually adaptive photomemristor.

8. The preparation method according to claim 7, characterized in that, The heat annealing conditions in step 3 are as follows: annealing at 400~500℃ for 30 minutes to 2 hours in an air atmosphere.

9. The preparation method according to claim 7, characterized in that, The heat annealing conditions in step 4 are as follows: annealing at 120~140℃ in a vacuum environment for 60~90 minutes.

10. The preparation method according to claim 7, characterized in that, In step 5, during the photolithography development process, the PEDOT:PSS film will swell slightly. After soaking in the developer, the device surface needs to be dried immediately and then baked to prevent excessive swelling of the PEDOT:PSS film from damaging the electrode pattern.

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