Neural mimicry bionic sensor and preparation method thereof

Abstract

The invention discloses a neural mimicry bionic sensor and a preparation method of the neural mimicry bionic sensor, and relates to the technical field of intelligent sensing materials and bionic electronic devices. The core bottleneck of a conductive polymer sensor in sensitivity, anti-interference performance and environmental adaptability is solved, the sensor is particularly suitable for dynamic signal response and noise suppression in chemical sensing, biomolecule detection and flexible wearable equipment, the jump type conductive mode of bionic axons greatly reduces transition noise between random chains, and the background signal-to-noise ratio is effectively improved; the on-demand release of the ionic liquid microcapsule enables the conductivity of a high-conductivity junction region to have gradient regulation and control capability, the detection limit on target molecules is low, and meanwhile, non-specific response can be actively inhibited in a strong interference environment; the collaborative design of the wrinkle buffer layer and the three-dimensional conductive network enables the sensor to have low sensitivity attenuation after thousands of bending cycles, and is suitable for long-term dynamic monitoring of wearable equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent sensing materials and bionic electronic devices, and particularly relates to a neuromorphic bionic sensor and a preparation method thereof. Background Art

[0002] In the forefront sensing fields such as chemical pollutant monitoring, biomarker detection, and flexible electronic skin, conductive polymer materials are regarded as ideal candidates for a new generation of sensors due to their excellent electrochemical activity and structural designability. As a typical conductive polymer, polyaniline (PANI) has attracted much attention from researchers due to its reversible doping / dedoping characteristics and environmental stability. However, existing PANI-based sensors face significant challenges in practical applications: the traditional conductive network relies on the carrier transition between randomly distributed molecular chains, resulting in the background electrical signal being easily interfered by the environment, such as temperature drift or non-target molecule adsorption, and the signal-to-noise ratio is much lower than that of commercial metal oxide sensors; the nano-porous or high specific surface area structures designed for high sensitivity often sacrifice mechanical stability, and the conductive paths are easily broken under dynamic bending or swelling conditions, and the performance deteriorates rapidly after long-term use; in addition, the conventional PANI sensing mechanism relies on the global regulation of the bulk doping level, and it is difficult to respond to weak or transient stimuli in real time, such as trace gases or micro-strain, and the response delay severely restricts its application in rapid detection scenarios.

[0003] In view of the above contradictions, the unique electrical signal transmission mechanism of the mammalian neuron axon system provides a subversive inspiration. The myelin sheath wrapped outside the axon is arranged alternately with insulating segments and highly conductive Ranvier nodes, forcing the electrical signal to be transmitted in a jumping manner, which not only reduces signal attenuation but also significantly improves the conduction efficiency. This "insulation-conduction" periodic structure essentially forms a dual mechanism of noise filtering and path optimization, which highly coincides with the anti-interference ability and sensitivity enhancement requirements of sensors. At the same time, the dynamic plasticity of neuron synapses - the precise regulation of signal strength and frequency is achieved through the quantization release of neurotransmitters, providing a bionic paradigm for the dynamic adaptability of sensing responses. Although existing technologies have tried to improve the performance of PANI by compounding conductive fillers (such as carbon nanotubes, graphene) or microstructural design (such as porous skeletons, microcolumn arrays), these improvements are mostly limited to local optimization and do not touch on the innovation of the conduction mechanism of the conductive network. For example, Patent CN115746296B improves the conductivity by compounding PANI with carbon nanotubes, but humidity and temperature changes still cause significant baseline drift; Patent CN106497050A uses a template method to construct a porous PANI skeleton to increase active sites, but the device stability deteriorates due to the collapse of conductive chains under mechanical deformation; Patent CN117965018A designs a microcolumn array structure to enhance the piezoresistive characteristics, but it needs to rely on an external circuit to compensate for the insufficient intrinsic sensitivity, resulting in an increase in power consumption and integration complexity.

[0004] Generally speaking, the existing technologies are still limited by the randomness of the conduction path, the structure-function contradiction, and the staticization of the response mechanism, and cannot achieve the coordination of high signal-to-noise ratio, high stability, and dynamic adaptability. Based on this, the present invention breaks through the traditional idea of material modification, deeply imitates the myelin-schwann node hierarchical structure of neuron axons and the synaptic dynamic regulation mechanism, constructs a polyaniline hierarchical conductive network and couples in-situ regulation methods, and innovates the sensor performance from the level of conduction mechanism, providing a new solution for intelligent sensing technology. Summary of the Invention

[0005] Aiming at the inherent defects of traditional polyaniline sensors in terms of sensitivity, anti-noise performance, and dynamic response, the present invention proposes a neuromorphic bionic sensor and its preparation method, which realizes multi-dimensional improvement of sensing performance by constructing a hierarchical conductive network with alternating insulation and conduction and an adaptive signal transmission mechanism.

[0006] A neuromorphic bionic sensor, comprising: Composite conductive network matrix: composed of periodically alternating highly conductive junction regions and insulating sheath layers. The highly conductive junction region is a composite system of nitrogen-doped carbon nanotubes and highly oxidized polyaniline, and the oxidation degree of the highly oxidized polyaniline is 70%-85%, forming an electron transmission backbone; the insulating sheath layer is a blend of low-oxidation-state polyaniline and polyimide, and the oxidation degree of the low-oxidation-state polyaniline is ≤20%. It is coated on the surface of the highly conductive junction region through a spin-coating process to form an insulating interval with a thickness of 50-200 nm. Dynamic gating unit: an ionic liquid microcapsule embedded in the highly conductive junction region, including a pH-responsive polydopamine shell layer and an ionic liquid [EMIM][TFSI] loaded in the core, and the content of the ionic liquid [EMIM][TFSI] loaded in the core is 10%-30%. Mechanical buffer layer: a polydimethylsiloxane (PDMS) elastic layer covering the conductive network matrix, with a thickness of 1-5 μm, and a wrinkled structure imitating the axonal plasma membrane is formed on the surface by laser etching. Signal modulation electrode: composed of a serpentine gold electrode array, the electrode width is 10-50 μm, the interval is 100-200 μm, and it is vertically and cross-arranged with the highly conductive junction region, and the charge injection efficiency is regulated through the interfacial Schottky barrier to reduce the background noise. Preferably, the period ratio of the highly conductive junction region to the insulating sheath layer is 2:1 to 5:1, that is, the ratio of the junction region length to the sheath layer thickness. The length of the highly conductive junction region is 20-50 μm, and the thickness of the insulating sheath layer is 10-25 μm, simulating the distribution law of the Schwann nodes of natural axons. Preferably, the polydopamine shell layer of the ionic liquid microcapsule undergoes controllable rupture when pH > 8 or local strain > 5%. The released ionic liquid preferentially infiltrates the highly conductive junction region, increasing the conductivity of this region by 2 - 3 orders of magnitude. The thickness of the polydopamine shell layer is 80 - 150 nm, and the surface of the microcapsule is modified with an amino-silane coupling agent and bonded to the surface of carbon nanotubes; Preferably, the depth of the wrinkled structure of the mechanical buffer layer is 0.5 - 2 μm, and the wrinkle density is 50 - 200 lines / mm, which matches the bending curvature of the serpentine electrode, ensuring that the resistance change rate of the device is < 5% under 30% tensile deformation; Preferably, the line width of the signal modulation electrode is 10 - 50 μm, and the interval is 100 - 200 μm. A titanium dioxide seed layer with a thickness of 3 - 10 nm is formed at the contact interface between the electrode array and the biomimetic myelin sheath layer.

[0007] A preparation method of a neuromorphic bionic sensor includes the following steps: Step 1: Substrate functionalization: Deposit a titanium dioxide seed layer with a thickness of 10 - 50 nm on the surface of a flexible polyimide substrate by ion sputtering, and then perform ultraviolet ozone treatment to improve the surface hydrophilicity; Step 2: Construction of the conductive network: Use inkjet printing technology to position and deposit highly oxidized polyaniline ink to form an array of highly conductive junction regions with an interval of 50 - 200 μm; Chemically vapor deposit nitrogen-doped carbon nanotubes with a diameter of 10 - 30 nm, a length of 1 - 5 μm, and a density of 10² - 10³ tubes / μm² on the surface of the junction region; Spin-coat a mixed solution of low-oxidation-state polyaniline / polyimide, and selectively retain the insulating sheath region through a mask exposure and development process, with the thickness accuracy controlled within ±10 nm; Step 3: Integration of the dynamic gating unit: Mix ionic liquid microcapsules and the thermoresponsive hydrogel Pluronic F127 in a mass ratio of 1:3, and precisely inject them into the edge of the highly conductive junction region through microfluidic spraying technology. After curing, a stimulus-responsive touch point is formed; Step 4: Encapsulation of the mechanical buffer layer: Laminate a PDMS film using a roll-to-roll process, form a biomimetic wrinkled structure by femtosecond laser etching, and align and bond it with the electrode array; Step 5: In-situ signal calibration and dynamic feedback regulation, establish a sensing response characteristic database by applying a bias voltage and a target stimulus.

[0008] Preferably, in Step 2, the growth of the nitrogen-doped carbon nanotubes uses a magnetron-sputtered nickel catalyst layer, and the CVD process conditions are Flow ratio 1:5, react at 750 °C for 30 minutes, with a tube diameter of 10 - 30 nm and a density of 10² - 10³ tubes / μm²; Preferably, the coating process of the microcapsules in step three includes: vacuum impregnating the mesoporous silica support with the ionic liquid [EMIM][TFSI], and then dynamically depositing a polydopamine shell layer in a pH = 8.5 buffer solution. The diameter of the microcapsules is 1 - 3 μm, and the loading amount is ≥60 wt%. Preferably, the femtosecond laser etching parameters in step four are a wavelength of 1030 nm, a pulse energy of 50 μJ, a line spacing of 15 μm, and the etching depth accuracy is controlled within ±5%. Preferably, the dynamic feedback regulation in step five includes PID control of the ionic liquid release rate, and the response trigger threshold is pH > 8 or strain > 5%.

[0009] Advantages of the present invention: By simulating the insulating - conducting alternating structure of neuron axons and the saltatory electrical signal transmission mechanism, the present invention solves the core bottlenecks of conductive polymer sensors in terms of sensitivity, anti - interference ability, and environmental adaptability. It is especially suitable for dynamic signal response and noise suppression in chemical sensing, biomolecule detection, and flexible wearable devices. The saltatory conduction mode of the bionic axon greatly reduces the random inter - chain transition noise, effectively improving the background signal - to - noise ratio; dynamic sensitivity adaptation: the on - demand release of ionic liquid microcapsules enables the conductivity of the high - conductivity junction region to have gradient regulation ability, with a low detection limit for target molecules, and can actively suppress non - specific responses in a strong interference environment; the collaborative design of the wrinkled buffer layer and the three - dimensional conductive network enables the sensor to have a low sensitivity decay after thousands of bending cycles, suitable for long - term dynamic monitoring of wearable devices; through the self - adaptive activation mechanism of the gating unit, the standby power consumption is low; the inkjet printing and roll - to - roll encapsulation processes are suitable for the manufacture of large - area flexible devices, breaking through the bottleneck of large - scale application of bionic sensors. Description of the Drawings

[0010] Figure 1 is a schematic diagram of the neuron axon of the present invention; Figure 2 is a schematic diagram of the bionic mapping of the nodes of Ranvier and myelin sheath of the present invention. Detailed Embodiments

[0011] Please refer to Figure 1 and Figure 2 As shown, a neuromorphic bionic sensor includes: Composite conductive network matrix: composed of periodically alternating high - conductivity junction regions and insulating sheath layers. The high - conductivity junction region is a composite system of nitrogen - doped carbon nanotubes and highly oxidized polyaniline, and the oxidation degree of the highly oxidized polyaniline is 70% - 85%, forming an electron - transport backbone; the insulating sheath layer is a blend of low - oxidized polyaniline and polyimide, and the oxidation degree of the low - oxidized polyaniline is ≤20%. It is covered on the surface of the high - conductivity junction region through a spin - coating process to form an insulating interval with a thickness of 50 - 200 nm. Specifically, the highly conductive junction region is the artificial Ranvier node, and the insulating sheath layer is the biomimetic myelin sheath; Dynamic gating unit: an ionic liquid microcapsule embedded in the highly conductive junction region, including a pH-responsive polydopamine shell layer and an ionic liquid [EMIM][TFSI] loaded in the core, and the content of the ionic liquid [EMIM][TFSI] loaded in the core is 10%-30%; Specifically, when a target molecule is adsorbed or mechanical deformation occurs at the sensing interface, local pH value or stress changes trigger the rupture of the microcapsule shell layer, releasing ionic liquid to regulate the conductivity of the junction region and realizing self-adaptive signal amplification; Mechanical buffer layer: a polydimethylsiloxane (PDMS) elastic layer covering the conductive network substrate, with a thickness of 1-5 μm, and a wrinkled structure imitating the axonal plasma membrane is formed on the surface by laser etching; Specifically, the mechanical buffer layer can effectively disperse external forces and maintain the integrity of the conductive network structure; Signal modulation electrode: composed of a serpentine gold electrode array, with an electrode width of 10-50 μm, a spacing of 100-200 μm, and is vertically cross-arranged with the highly conductive junction region, and the charge injection efficiency is regulated through the interfacial Schottky barrier to reduce the background noise; Preferably, the period ratio of the highly conductive junction region to the insulating sheath layer is 2:1 to 5:1, that is, the ratio of the junction region length to the sheath layer thickness. The length of the highly conductive junction region is 20-50 μm, and the thickness of the insulating sheath layer is 10-25 μm, simulating the distribution law of Ranvier nodes of natural axons; Preferably, the polydopamine shell layer of the ionic liquid microcapsule undergoes controllable rupture when pH > 8 or local strain > 5%, and the released ionic liquid preferentially infiltrates the highly conductive junction region, increasing the conductivity of this region by 2-3 orders of magnitude. The thickness of the polydopamine shell layer is 80-150 nm, and the surface of the microcapsule is modified with an amino silane coupling agent and bonded to the surface of the carbon nanotube; Preferably, the depth of the wrinkled structure of the mechanical buffer layer is 0.5-2 μm, and the wrinkled density is 50-200 lines / mm, which matches the bending curvature of the serpentine electrode to ensure that the resistance change rate of the device is < 5% under 30% tensile deformation; Preferably, the line width of the signal modulation electrode is 10-50 μm, the spacing is 100-200 μm, and a titanium dioxide seed layer with a thickness of 3-10 nm is formed at the contact interface between the electrode array and the biomimetic myelin sheath layer.

[0012] A preparation method of a neuromorphic biomimetic sensor includes the following steps: Step 1: Substrate functionalization treatment: Deposit a titanium dioxide seed layer with a thickness of 10-50 nm on the surface of a flexible polyimide substrate by ion sputtering, and then perform ultraviolet ozone treatment to improve the surface hydrophilicity; Step 2: Construction of the conductive network: Use inkjet printing technology to position and deposit high-oxidation-state polyaniline ink to form an array of highly conductive junction regions spaced 50 - 200 μm apart; chemically vapor deposit nitrogen-doped carbon nanotubes on the surface of the junction regions, with a tube diameter of 10 - 30 nm, a length of 1 - 5 μm, and a density of 10² - 10³ tubes / μm²; spin-coat a low-oxidation-state polyaniline / polyimide mixed solution, and selectively retain the insulating sheath region through a mask exposure and development process, with the thickness accuracy controlled within ±10 nm; Step 3: Integration of the dynamic gating unit: Mix ionic liquid microcapsules and the thermoresponsive hydrogel Pluronic F127 in a mass ratio of 1:3, and precisely inject them into the edge of the highly conductive junction region through microfluidic spraying technology. After curing, a stimulus-responsive touch point is formed; Step 4: Encapsulation with a mechanical buffer layer: Use a roll-to-roll process to laminate a PDMS film, form a biomimetic wrinkled structure through femtosecond laser etching, and align and bond it with the electrode array; Step 5: In-situ signal calibration and dynamic feedback regulation, establish a sensing response characteristic database by applying a bias voltage and target stimuli.

[0013] Preferably, in Step 2, the growth of the nitrogen-doped carbon nanotubes uses a magnetron sputtered nickel catalyst layer, and the CVD process conditions are a flow rate ratio of 1:5, reacting at 750 °C for 30 minutes, with a tube diameter of 10 - 30 nm and a density of 10² - 10³ tubes / μm²; Preferably, the encapsulation process of the microcapsules in Step 3 includes: vacuum impregnating a mesoporous silica carrier with the ionic liquid [EMIM][TFSI], and then dynamically depositing a polydopamine shell layer in a pH = 8.5 buffer solution. The microcapsules have a diameter of 1 - 3 μm and a loading amount of ≥60 wt%; Preferably, the femtosecond laser etching parameters in Step 4 are a wavelength of 1030 nm, a pulse energy of 50 μJ, a line spacing of 15 μm, and the etching depth accuracy is controlled within ±5%; Preferably, the dynamic feedback regulation in Step 5 includes PID control of the ionic liquid release rate, and the response trigger threshold is pH > 8 or strain > 5%.

[0014] Example: A neuromorphic bionic sensor includes: Composite conductive network matrix: It includes periodically alternating highly conductive junction regions and insulating sheath layers. The highly conductive junction regions are composed of nitrogen-doped carbon nanotubes (with a tube diameter of 10 - 30 nm, a length of 1 - 5 μm, and a density of 10² - 10³ tubes / μm²) and polyaniline in a highly oxidized state (oxidation degree of 70% - 85%); the insulating sheath layer is a blend of polyaniline in a low oxidized state (oxidation degree ≤ 20%) and polyimide (mass ratio 1:1). After spin coating, an insulating spacer with a thickness of 50 - 200 nm is formed. The length of the highly conductive junction region is 20 - 50 μm, the thickness of the insulating sheath layer is 10 - 25 μm, and the period ratio (junction region length: sheath layer thickness) is 2:1 to 5:1.

[0015] Dynamic gating unit: Ionic liquid microcapsules embedded in the highly conductive junction region, containing a pH-responsive polydopamine shell layer (thickness 80 - 150 nm) and ionic liquid [EMIM][TFSI] in the core (loading amount 10% - 30%). The surface of the microcapsules is modified with an amino silane coupling agent and bonded to the surface of the carbon nanotubes.

[0016] Mechanical buffer layer: A polydimethylsiloxane (PDMS) elastic layer with a thickness of 1 - 5 μm, and a wrinkled structure (depth 0.5 - 2 μm, density 50 - 200 lines / mm) mimicking the axonal plasma membrane is formed on the surface by femtosecond laser etching.

[0017] Signal modulation electrode: A serpentine gold electrode array (line width 10 - 50 μm, spacing 100 - 200 μm), deposited on a polyimide substrate by electron beam evaporation, arranged perpendicular to the highly conductive junction region, and the charge injection efficiency is regulated through the Schottky barrier.

[0018] A preparation method of a neuromorphic bionic sensor includes: Step 1: Substrate functionalization Select a flexible polyimide film with a thickness of 125 μm (grade Kapton HN, DuPont), and cut it into a 50×50 mm square substrate; Surface seed layer deposition: Place the substrate in the ion sputtering chamber, evacuate to and then introduce argon (purity 99.999%, pressure 1.0 Pa), and sputter a titanium dioxide target (purity 99.99%) with a radio frequency power of 80 W for 15 minutes to deposit a titanium dioxide seed layer with a thickness of 20 ± 2 nm; Ultraviolet ozone treatment: Transfer the deposited substrate to an ultraviolet ozone cleaner (wavelength 185 nm / 254 nm), and treat it for 30 minutes. The surface contact angle drops from 110° to <5°, forming a superhydrophilic interface; Step 2: Conductive network construction Array printing of highly conductive junction regions: Preparation of high-oxidation-state polyaniline ink: Dissolve aniline monomer (Aladdin reagent, purity ≥ 99.5%) in 1 M HCl (concentration 0.2 M), add 0.3 M ammonium persulfate as the oxidant, stir and polymerize at 40 °C for 4 hours. After the reaction, centrifuge and wash three times (rotation speed 8000 rpm, 15 minutes), and disperse in NMP solvent to form a 5 wt% dispersion; Using an inkjet printing system (Fuji Dimatix DMP-2831), set the nozzle temperature at 25 °C, the substrate temperature at 40 °C, and the droplet spacing at 50 μm. Print a rectangular junction area array (size 30×100 μm) with a spacing of 150 μm on the titanium dioxide seed layer. After printing, place it in a vacuum oven at 80 °C and dry for 1 hour; Growth of nitrogen-doped carbon nanotubes: Catalyst deposition: Place the substrate printed with polyaniline in a magnetron sputtering instrument and sputter nickel catalyst (thickness 5 nm). Sputtering conditions: background vacuum , argon pressure 0.8 Pa, power 100 W, substrate rotation speed 10 rpm; Chemical vapor deposition (CVD): Transfer the substrate to a quartz tube furnace and introduce a mixed gas (flow ratio 1:5, total flow 200 sccm), heat up to 750 °C (rate 10 °C / min), and hold for 30 minutes. Carbon nanotubes grow radially on the surface of polyaniline; Preparation of insulating sheath layer: Preparation of low-oxidation-state polyaniline / polyimide mixture: Dissolve low-oxidation-degree polyaniline (synthesized by 0.05 M APS oxidation) and polyimide in NMP at a mass ratio of 1:1, with a solid content of 10%; Spin coating process: Spin coat the mixture at 3000 rpm for 30 seconds to cover the area outside the high-conductivity junction region, forming an insulating layer with a thickness of 150 ± 10 nm. Selectively cure the polyimide by ultraviolet light mask exposure (wavelength 365 nm, energy 200 mJ / cm²), and strip the unexposed area with acetone / ethanol (volume ratio 3:1) to retain the insulating sheath region.

[0019] Step 3: Integration of dynamic gating unit Synthesis of ionic liquid microcapsules: Immerse mesoporous silica (pore diameter 5 nm, specific surface area 900 m² / g) in an ethanol solution containing [EMIM][TFSI] (concentration 0.5 M) and vacuum immerse for 8 hours; Coat with a polydopamine shell layer: Disperse the silica loaded with liquid in Tris-HCl buffer solution (pH 8.5) containing 2 mg / mL dopamine, stir at 25 °C in the dark for 24 hours, centrifuge, wash and dry to obtain microcapsules (particle size 1-3 μm, shell layer thickness 120 ± 20 nm); Microcapsule positioning and assembly: Mix microcapsules with thermosensitive Pluronic F127 hydrogel (mass ratio 1:3), and precisely deposit them on the edge of the highly conductive junction area through a microfluidic spraying system (Nordson EFD Ultra2400). The nozzle diameter is 50 μm, the spraying pressure is 20 psi, and a dynamic touch point array is formed after curing; Step Four: Encapsulation with a mechanical buffer layer Mix the PDMS prepolymer (Sylgard 184, Dow Corning) with the curing agent at a mass ratio of 10:1. After degassing, laminate it on the surface of the conductive network by a roll-to-roll process to form a 2-μm-thick elastic layer; Laser etching of the wrinkled structure: Use a laser to etch the surface of PDMS in a line scanning mode with a line spacing of 15 μm and a depth of 1.5 μm to form a biomimetic wrinkle. The laser power is controlled by a closed-loop feedback system with an error <±2%; Step Five: In-situ signal calibration and feedback regulation Place the sensor in a temperature and humidity control chamber (25 ± 0.5°C, RH 50 ± 3%), and connect it to a digital source meter (Keithley2450) and a data acquisition system.

[0020] It should be understood that the application of the present invention is not limited to the above examples. For those of ordinary skill in the art, improvements or transformations can be made according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of the present invention.

Claims

1. A neuromorphic bionic sensor, characterized in that, Comprising: Composite conductive network matrix: Composed of periodically alternating high-conductivity junction regions and insulating sheath layers. The high-conductivity junction region is a composite system of nitrogen-doped carbon nanotubes and highly oxidized polyaniline, and the degree of oxidation of the highly oxidized polyaniline is 70% - 85%, forming an electron transport backbone; the insulating sheath layer is a blend of low-oxidation-state polyaniline and polyimide, and the degree of oxidation of the low-oxidation-state polyaniline is ≤20%. It covers the surface of the high-conductivity junction region through a spin-coating process to form an insulating spacer with a thickness of 50 - 200 nm; Dynamic gating unit: Ionic liquid microcapsules embedded in the high-conductivity junction region, including a pH-responsive polydopamine shell layer and ionic liquid [EMIM][TFSI] loaded in the core, and the content of ionic liquid [EMIM][TFSI] loaded in the core is 10% - 30%; Mechanical buffer layer: A polydimethylsiloxane (PDMS) elastic layer covering the conductive network matrix, with a thickness of 1 - 5 μm, and a wrinkled structure imitating the axonal membrane is formed on the surface by laser etching; Signal modulation electrode: Composed of a serpentine gold electrode array, the electrode width is 10 - 50 μm, the interval is 100 - 200 μm, and it is vertically cross-arranged with the high-conductivity junction region. The charge injection efficiency is regulated through the interface Schottky barrier to reduce the background noise.

2. The neuromorphic bionic sensor according to claim 1, wherein The period ratio of the high-conductivity junction region to the insulating sheath layer is 2:1 to 5:1, that is, the ratio of the junction region length to the sheath layer thickness. The length of the high-conductivity junction region is 20 - 50 μm, and the thickness of the insulating sheath layer is 10 - 25 μm, simulating the distribution law of Ranvier nodes of natural axons.

3. The neuromorphic bionic sensor according to claim 2, characterized in that, The polydopamine shell layer of the ionic liquid microcapsule undergoes controllable rupture when pH > 8 or local strain > 5%. The released ionic liquid preferentially infiltrates the high-conductivity junction region, increasing the conductivity of this region by 2 - 3 orders of magnitude. The thickness of the polydopamine shell layer is 80 - 150 nm, and the surface of the microcapsule is modified with an amino silane coupling agent and bonded to the surface of the carbon nanotubes.

4. A neuromorphic bionic sensor according to claim 3, characterized in that, The depth of the wrinkled structure of the mechanical buffer layer is 0.5 - 2 μm, and the wrinkled density is 50 - 200 lines / mm, which matches the bending curvature of the serpentine electrode to ensure that the resistance change rate of the device is <5% under 30% tensile deformation.

5. A neuromorphic bionic sensor according to claim 4, characterized in that, The line width of the signal modulation electrode is 10 - 50 μm, the interval is 100 - 200 μm, and a titanium dioxide seed layer with a thickness of 3 - 10 nm is formed at the contact interface between the electrode array and the biomimetic myelin sheath layer.

6. A preparation method of a neuromorphic bionic sensor for preparing a neuromorphic bionic sensor according to any one of claims 1 to 5, characterized in that, Including the following steps: Step 1: Substrate functionalization treatment: Deposit a titanium dioxide seed layer with a thickness of 10 - 50 nm on the surface of a flexible polyimide substrate through ion sputtering, and then perform ultraviolet ozone treatment to improve the surface hydrophilicity; Step 2: Conductive network construction: Use inkjet printing technology to position and deposit highly oxidized polyaniline ink to form an array of high-conductivity junction regions with an interval of 50 - 200 μm; Chemically vapor deposit nitrogen-doped carbon nanotubes with a diameter of 10 - 30 nm and a length of 1 - 5 μm and a density of 10² - 10³ roots / μm² on the surface of the junction region; Spin-coat a low-oxidation-state polyaniline / polyimide mixed solution, and selectively retain the insulating sheath region through a mask exposure and development process, with the thickness accuracy controlled within ±10 nm; Step 3: Dynamic gating unit integration: Mix the ionic liquid microcapsules and the thermoresponsive hydrogel Pluronic F127 at a mass ratio of 1:3, and precisely inject them into the edge of the highly conductive junction region through microfluidic spraying technology. After curing, a stimulus-responsive touch point is formed. Step 4: Mechanical buffer layer encapsulation: Laminate the PDMS film using a roll-to-roll process, form a biomimetic wrinkled structure through femtosecond laser etching, and align and bond it with the electrode array. Step 5: In-situ signal calibration and dynamic feedback regulation, establish a sensing response characteristic database by applying a bias voltage and target stimuli.

7. The preparation method of a neuromorphic bionic sensor according to claim 6, wherein, In step 2, the growth of the nitrogen-doped carbon nanotubes uses a magnetron sputtered nickel catalyst layer. The CVD process conditions are a CH4 / NH3 flow ratio of 1:5, a reaction at 750 °C for 30 minutes, a tube diameter of 10 - 30 nm, and a density of 10² - 10³ tubes / μm².

8. The preparation method of a neuromorphic bionic sensor according to claim 7, characterized in that, The encapsulation process of the microcapsules in step 3 includes: vacuum impregnating the mesoporous silica carrier with the ionic liquid [EMIM][TFSI], and then dynamically depositing a polydopamine shell layer in a pH = 8.5 buffer solution. The microcapsule diameter is 1 - 3 μm, and the loading amount is ≥60 wt%.

9. The preparation method of a neuromorphic bionic sensor according to claim 8, wherein, The femtosecond laser etching parameters in step 4 are a wavelength of 1030 nm, a pulse energy of 50 μJ, a line spacing of 15 μm, and the etching depth accuracy is controlled within ±5%.

10. The preparation method of a neuromorphic bionic sensor according to claim 9, characterized in that, The dynamic feedback regulation in step 5 includes PID control of the ionic liquid release rate, and the response trigger threshold is pH > 8 or strain > 5%.

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