Preparation method and application of nano composite material with infrared stealth energy storage function

Abstract

The invention discloses a preparation method and application of a nano composite material with infrared stealth energy storage, and relates to the technical field of new materials. According to the invention, cooperation is formed through efficient energy storage of MXene and infrared protection of vanadium dioxide, during normal work, the MXene supercapacitor continuously stores electric energy, and long-acting energy support is provided for the sensor to stably monitor the environment temperature; meanwhile, the vanadium dioxide film plays an infrared protection role, can reflect infrared radiation in an external environment, prevents high-temperature infrared energy from damaging internal elements of the sensor and has excellent reversible phase change and cycling stability, the reversible phase change characteristic of the vanadium dioxide film is deeply matched with the energy storage cycling stability of MXene, and the performance of the sensor is improved. And the infrared protection function of vanadium dioxide runs through the whole process. In multiple temperature rising and falling cycles, vanadium dioxide can be stably switched between a semiconductor phase and a conductor phase, the phase change performance is not attenuated, infrared radiation is continuously blocked, and a sensor core module is protected.

Description

Technical Field

[0001] This invention relates to the field of new materials technology, specifically to a method for preparing and applying a nanocomposite material with infrared stealth energy storage. Background Technology

[0002] Infrared optoelectronic detection equipment has become a core component of advanced avionics systems. The airborne infrared search and track (IRST) systems of advanced fighter jets, the infrared detection modules of high-precision missiles, and the infrared thermal imaging equipment integrated into UAV pods all rely on infrared signals to achieve target search, tracking, and identification. The stable operation of these devices requires a continuous power supply and efficient infrared protection.

[0003] In the current battlefield environment, laser weapons, with their advantages of high attack speed and strong resistance to electromagnetic interference, pose a severe threat to infrared optoelectronic devices, potentially causing structural damage and functional failure. These devices also require energy to operate. Traditional solutions separate infrared protection and energy storage systems, increasing equipment size and weight, and making them unsuitable for lightweight platforms such as fighter jets and drones. This makes integrated energy storage and infrared protection materials a critical requirement—materials must maintain high transmittance in infrared detection windows of 3-5 μm and 8-12 μm under normal operating conditions to ensure detection accuracy, while continuously powering the equipment; and when attacked by lasers, they must respond quickly to provide protection, preventing device damage, and truly achieving synergistic "power supply-protection."

[0004] In the field of flexible electronics, the demand for "flexibility, lightweight, and high adaptability" in wearable electronics, smart healthcare, and other scenarios is driving the rapid development of flexible energy storage technology. However, if these flexible electronic devices are applied to scenarios such as military reconnaissance (e.g., flexible infrared detection clothing) and polar scientific expeditions, they not only need flexible energy storage materials to provide stable energy, but also need to cope with infrared radiation interference or laser threats in complex environments.

[0005] Therefore, flexible energy storage and infrared protection integrated materials have become a new research direction: through material system innovation and cross-scale structural design, while ensuring mechanical flexibility (bendable, foldable, and stretchable), it is necessary to balance energy density, power density, and cycle stability to power flexible devices, and at the same time, it is necessary to have infrared protection capabilities in specific bands to meet the usage requirements in different scenarios. A new solution is needed to address the above issues. Summary of the Invention

[0006] The purpose of this invention is to provide a method for preparing and applying a nanocomposite material with infrared stealth energy storage, so as to solve the technical problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing a nanocomposite material with infrared stealth energy storage, comprising at least the following steps: Step 1: Prepare MXene material to obtain a monolayer MXene dispersion; Step 2: Prepare PANI@ANFs; Step 3: Preparation of M / PA / M using MXene and PANI@ANFs; Step 4: Equipment pretreatment. Use fine sandpaper to polish the equipment chamber walls and wipe them with ethanol to ensure no impurities or contamination. Finally, place the substrate in the target sputtering center to ensure uniform deposition. Step 5: Coating pretreatment. Vacuum is drawn using mechanical and molecular pumps, and the temperature is adjusted and kept warm. Then, argon and oxygen are introduced for repeated degassing and cleaning. Pre-sputtering is then performed to clean the target surface. Step 6: Deposit thin film. After pre-sputtering, adjust the gas pressure and start sputtering deposition. After deposition, slowly cool to room temperature in an argon atmosphere.

[0008] Furthermore, step 1 includes at least the following steps: Mix LiF with 3M-9M HCl in a polytetrafluoroethylene beaker, and stir the mixture continuously at 20℃-70℃ until it is completely dissolved. The Ti3AlC2 was then stirred at 300 rpm for 20-40 hours to etch the Al layer. Afterwards, the mixture was washed multiple times with deionized water until the pH of the mixed solution reached 6, and then dried in a vacuum environment at 50℃-100℃ for 16h-24h. The dried product is then dispersed in deionized water by ultrasonication to obtain a monolayer MXene dispersion.

[0009] Furthermore, step 2 includes at least the following steps: First, the PPTA fibers are dissolved: PPTA fibers and potassium hydroxide (KOH) were added to a dimethyl sulfoxide (DMSO) solution and stirred until homogeneous. Using a magnetic stirrer, the mixture was stirred continuously at room temperature for 5–7 days until the PPTA fibers were completely dissolved and the solution turned dark red. After dissolution, the solution was washed multiple times with deionized water to remove potassium hydroxide and dimethyl sulfoxide. To ensure complete dispersion, the solution was ultrasonically treated with a probe to uniformly disperse the fibers in water, thus obtaining an aromatic nanofibers (ANFs) aqueous dispersion. Then, the aniline-initiated polymerization reaction is carried out: The obtained aromatic nanofiber aqueous dispersion was mixed with concentrated sulfuric acid (H2SO4), and aniline (50 µL to 200 µL, depending on the reaction requirements) was added as a polymerization initiator. The mixture was stirred with a magnetic stirrer for 10 to 45 minutes at a low temperature of 0-10°C to ensure that the aniline was evenly distributed and the polymerization reaction started. The stirred mixture was then transferred to a refrigerator and polymerized at 0-10°C for 2 to 5 hours.

[0010] Furthermore, step 3 includes at least the following steps: MXene, PANI@ANFs and MXene were vacuum filtered in sequence to form a sandwich film, denoted as M / PA / M; The membrane obtained after MXene filtration is denoted as the MXene membrane. The same method is used for the mixed membranes of MXene, PANI@ANFs and MXene. MXene and PANI@ANFs were mixed using magnetic stirring, then placed in a refrigerator for polymerization for 5 hours. Finally, the mixture was filtered to form a composite film, denoted as M / PA.

[0011] Furthermore, step 4 includes at least the following steps: Before the experiment, use fine sandpaper to polish the cabin walls; Then, wipe with ethanol to prevent impurities from contaminating the film and affecting its quality; Finally, the substrate is placed on a disk in the center region of the target sputtering area, and the disk rotation speed is set to 10Hz-50Hz to ensure the uniformity of thin film deposition.

[0012] Furthermore, step 5 includes at least the following steps: The initial vacuum inside the chamber is first pre-evacuated using a mechanical pump. Once the pressure drops to 1.0 Pa-10.0 Pa, the baffle valve is opened to activate the molecular pump for further fine evacuation, raising the background vacuum of the chamber to 3.0 × 10⁻³ Pa-5.0 × 10⁻³ Pa. 4 After Pa, the working gas is introduced. After the required vacuum level in the chamber is reached, the heating system is turned on to raise the temperature of the M / PA / M substrate to the required 200°C-550°C for deposition, and the temperature is maintained for 30-60 minutes to ensure the stability of the vanadium oxide phase generated by reactive sputtering. Once the required temperature and vacuum level are reached, argon and oxygen are introduced and the gas flow rate is adjusted. Then, the gas is turned off and the cycle is repeated several times to remove any residual gas. After completion, set the DC pulse power supply parameters (power 60W-200W, pulse time 1-10μs, frequency 30-100kHz) and perform pre-sputtering for 5-20 minutes to clean the target surface and remove impurities such as oxides.

[0013] Furthermore, step 6 includes at least the following steps: After pre-sputtering is completed, adjust the angle valve to stabilize the thin film gauge at 0.4 Pa-1.2 Pa, open the baffle and start the sputtering timer; After deposition, turn off the DC pulse power supply and oxygen supply, and keep warm in an argon atmosphere of 30 sccm-200 sccm for 20-60 minutes; The heating power was then turned off, and the sample was allowed to cool slowly to room temperature under argon protection.

[0014] An application of a nanocomposite material with infrared stealth energy storage is described above, which is used in the preparation method of the aforementioned nanocomposite material with infrared stealth energy storage to assemble a supercapacitor.

[0015] Furthermore, the use of M / PA / M for assembling supercapacitors includes at least the following steps: Weigh 1 g-5 g of PVA and 5 ml-50 ml of H2SO4 and stir magnetically for 1 h-3 h in a water bath at 50℃-80℃ until the solution becomes a clear gel to obtain the PVA / H2SO4 electrolyte. A membrane loaded with PVA / H2SO4 can be obtained by immersing a piece of non-woven fabric in PVA / H2SO4 electrolyte. After the M / PA / M coating is cut, it is assembled in the following order: substrate, conductive copper foil, conductive silver paste, thin film, separator soaked in electrolyte, conductive silver paste, conductive copper foil and PET substrate, to obtain a symmetrical all-solid-state M / PA / M supercapacitor with infrared stealth.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention achieves synergy between the high-efficiency energy storage of MXene and the infrared protection of vanadium dioxide. During normal operation, the MXene supercapacitor continuously stores electrical energy, providing long-term power support for the sensor to stably monitor ambient temperature. Simultaneously, the vanadium dioxide film provides infrared protection, reflecting infrared radiation from the external environment and preventing damage to the sensor's internal components from high-temperature infrared energy. In the event of sudden temperature changes such as a fire, when the ambient temperature reaches the vanadium dioxide phase transition temperature, it instantly completes the semiconductor-conductor phase transition, rapidly converting the temperature signal into an electrical signal. At this time, MXene immediately releases its stored electrical energy, ensuring efficient transmission of the electrical signal and triggering an alarm. Compared to the several-second response time of traditional sensors, this invention achieves a microsecond-level response, gaining crucial time for emergency response. 2. This invention possesses excellent reversible phase transition and cycling stability. The reversible phase transition characteristics of the vanadium dioxide thin film are deeply compatible with the energy storage cycling stability of MXene, and the infrared protection function of vanadium dioxide is maintained throughout the entire process. During multiple temperature rise and fall cycles, vanadium dioxide can stably switch between the semiconductor and conductor phases without any degradation in phase transition performance, while continuously blocking infrared radiation to protect the core sensor module; the MXene supercapacitor can simultaneously withstand repeated charging and discharging, maintaining a high energy storage efficiency throughout, eliminating the need for frequent replacement of energy storage components. In industrial production and other scenarios with frequent temperature fluctuations, the two work together to ensure that the sensor can accurately capture temperature changes while relying on stable energy storage and infrared protection for long-term operation, significantly reducing maintenance costs and ensuring stable production processes. 3. This invention achieves breakthroughs in zero hysteresis width and multi-effect synergy. Through innovative preparation processes, the hysteresis width of the vanadium dioxide thin film is reduced to zero, completely solving the measurement deviation problem of traditional sensors. Its infrared protection capability is also further optimized, enabling more accurate resistance to infrared radiation in specific wavelengths. The energy storage advantage of the MXene supercapacitor provides strong support for this characteristic. Zero hysteresis width significantly improves the sensor's measurement accuracy near the phase transition point, accurately reflecting actual temperature changes. MXene continuously powers the temperature measurement module, ensuring that the response speed is not limited by energy supply. With the combination of these two, the sensor not only relies on the infrared protection of vanadium dioxide to isolate damage in high-temperature and harsh environments and maintains efficient operation with the energy storage of MXene, but also can be extended to the field of precision equipment monitoring where both infrared protection and energy storage stability are required, opening up new paths for the upgrading of temperature sensor technology. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a circumferential voltammetry scan test diagram from Embodiment 3 of the present invention; Figure 2 This is a constant current charge-discharge test diagram of Embodiment 3 of the present invention; Figure 3 This is a SEM image of Embodiment 3 of the present invention; Figure 4 This is a circumferential voltammetry scan test diagram from Embodiment 4 of the present invention; Figure 5 This is a constant current charge-discharge test diagram of Embodiment 4 of the present invention; Figure 6 This is a SEM image of Embodiment 4 of the present invention; Figure 7This is a circumferential voltammetry scan test diagram from Embodiment 5 of the present invention; Figure 8 This is a constant current charge-discharge test diagram from Embodiment 5 of the present invention; Figure 9 This is a SEM image of Embodiment 5 of the present invention; Figure 10 This is a schematic diagram of the present invention. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0020] This invention discloses a method for preparing a composite thin film with infrared stealth and energy storage effects. The invention employs multiple strategies, including constructing a three-dimensional porous structure and introducing other materials to form a composite material to prevent the self-stacking of MXene sheets. The prepared flexible composite thin film exhibits a typical sandwich structure. Biaxial magnetron sputtering is used to prepare the VO2 thin film, and the introduction of Ti impurity ions to replace vanadium ions effectively disrupts the V2 film. 4 ⁺-V 4 ⁺ Covalent bonds, thereby increasing defects in the thin film, can regulate the phase transition characteristics of vanadium dioxide thin films. Specifically, by precisely controlling the type, concentration, and doping method of impurity ions, their electrochemical performance in supercapacitors can be improved, enhancing the electrochemical activity of electrode materials, thereby increasing the specific capacitance and energy density of supercapacitors. Key parameters such as the phase transition temperature and hysteresis width of the thin film can be adjusted to achieve a narrower hysteresis range for rapid and sensitive response. In the entire process, a monolayer MXene dispersion is first obtained using conventional etching methods, while ANFs are obtained using conventional deprotonation methods. The PANI@ANFs coating structure is formed by monomer polymerization under acidic conditions, forming a stable conductive network in the intermediate layer. Finally, MXene, PANI@ANFs, and MXene are sequentially processed into a sandwich film (M / PA / M) through vacuum filtration. Using a sandwich-structured M / PA / M thin film as a substrate, a vanadium dioxide thin film is generated as a seed layer. Then, Ti element is introduced, and a biaxial co-sputtering mode is used. The doping concentration is adjusted by changing the sputtering power, and the oxygen content inside the cavity is kept constant by adjusting the inlet flow rate during sputtering.

[0021] Specifically as follows: Example

[0022] A method for preparing a nanocomposite material with infrared stealth energy storage includes at least the following steps: Step 1: Prepare MXene material to obtain a monolayer MXene dispersion; Step 2: Prepare PANI@ANFs; Step 3: Preparation of M / PA / M using MXene and PANI@ANFs; Step 4: Equipment pretreatment. Use fine sandpaper to polish the equipment chamber walls and wipe them with ethanol to ensure no impurities or contamination. Finally, place the substrate in the target sputtering center to ensure uniform deposition. Step 5: Coating pretreatment. Vacuum is drawn using mechanical and molecular pumps, and the temperature is adjusted and kept warm. Then, argon and oxygen are introduced for repeated degassing and cleaning. Pre-sputtering is then performed to clean the target surface. Step 6: Deposit thin film. After pre-sputtering, adjust the gas pressure and start sputtering deposition. After deposition, slowly cool to room temperature in an argon atmosphere.

[0023] Step 1 includes at least the following steps: Mix LiF with 3M-9M HCl in a polytetrafluoroethylene beaker, and stir the mixture continuously at 20℃-70℃ until it is completely dissolved. The Ti3AlC2 was then stirred at 300 rpm for 20-40 hours to etch the Al layer. Afterwards, the mixture was washed multiple times with deionized water until the pH of the mixed solution reached 6, and then dried in a vacuum environment at 50℃-100℃ for 16h-24h. The dried product is then dispersed in deionized water by ultrasonication to obtain a monolayer MXene dispersion.

[0024] Step 2 includes at least the following steps: First, the PPTA fibers are dissolved: PPTA fibers and potassium hydroxide (KOH) were added to a dimethyl sulfoxide (DMSO) solution and stirred until homogeneous. Using a magnetic stirrer, the mixture was stirred continuously at room temperature for 5–7 days until the PPTA fibers were completely dissolved and the solution turned dark red. After dissolution, the solution was washed multiple times with deionized water to remove potassium hydroxide and dimethyl sulfoxide. To ensure complete dispersion, the solution was ultrasonically treated with a probe to uniformly disperse the fibers in water, thus obtaining an aromatic nanofibers (ANFs) aqueous dispersion. Then, the aniline-initiated polymerization reaction is carried out: The obtained aromatic nanofiber aqueous dispersion was mixed with concentrated sulfuric acid (H2SO4), and aniline (50 µL to 200 µL, depending on the reaction requirements) was added as a polymerization initiator. The mixture was stirred with a magnetic stirrer for 10 to 45 minutes at a low temperature of 0-10°C to ensure that the aniline was evenly distributed and the polymerization reaction started. The stirred mixture was then transferred to a refrigerator and polymerized at 0-10°C for 2 to 5 hours.

[0025] Step 3 includes at least the following steps: MXene, PANI@ANFs and MXene were vacuum filtered in sequence to form a sandwich film, denoted as M / PA / M; The membrane obtained after MXene filtration is denoted as the MXene membrane. The same method is used for the mixed membranes of MXene, PANI@ANFs and MXene. MXene and PANI@ANFs were mixed using magnetic stirring, then placed in a refrigerator for polymerization for 5 hours. Finally, the mixture was filtered to form a composite film, denoted as M / PA.

[0026] Step 4 includes at least the following steps: Before the experiment, use fine sandpaper to polish the cabin walls; Then, wipe with ethanol to prevent impurities from contaminating the film and affecting its quality; Finally, the substrate is placed on a disk in the center region of the target sputtering area, and the disk rotation speed is set to 10Hz-50Hz to ensure the uniformity of thin film deposition.

[0027] Step 5 includes at least the following steps: The initial vacuum inside the chamber is first pre-evacuated using a mechanical pump. Once the pressure drops to 1.0 Pa-10.0 Pa, the baffle valve is opened to activate the molecular pump for further fine evacuation, raising the background vacuum of the chamber to 3.0 × 10⁻³ Pa-5.0 × 10⁻³ Pa. 4 After Pa, the working gas is introduced. After the required vacuum level in the chamber is reached, the heating system is turned on to raise the temperature of the M / PA / M substrate to the required 200°C-550°C for deposition, and the temperature is maintained for 30-60 minutes to ensure the stability of the vanadium oxide phase generated by reactive sputtering. Once the required temperature and vacuum level are reached, argon and oxygen are introduced and the gas flow rate is adjusted. Then, the gas is turned off and the cycle is repeated several times to remove any residual gas. After completion, set the DC pulse power supply parameters (power 60W-200W, pulse time 1-10μs, frequency 30-100kHz) and perform pre-sputtering for 5-20 minutes to clean the target surface and remove impurities such as oxides.

[0028] Step 6 includes at least the following steps: After pre-sputtering is completed, adjust the angle valve to stabilize the thin film gauge at 0.4 Pa-1.2 Pa, open the baffle and start the sputtering timer; After deposition, turn off the DC pulse power supply and oxygen supply, and keep warm in an argon atmosphere of 30 sccm-200 sccm for 20-60 minutes; The heating power was then turned off, and the sample was allowed to cool slowly to room temperature under argon protection. Example

[0029] An application of a nanocomposite material with infrared stealth energy storage is described in Example 1 above, which uses M / PA / M to assemble a supercapacitor.

[0030] Using M / PA / M to assemble supercapacitors includes at least the following steps: Weigh 1 g-5 g of PVA and 5 ml-50 ml of H2SO4 and stir magnetically for 1 h-3 h in a water bath at 50℃-80℃ until the solution becomes a clear gel to obtain the PVA / H2SO4 electrolyte. A membrane loaded with PVA / H2SO4 can be obtained by immersing a piece of non-woven fabric in PVA / H2SO4 electrolyte. After the M / PA / M coating is cut, it is assembled in the following order: substrate, conductive copper foil, conductive silver paste, thin film, separator soaked in electrolyte, conductive silver paste, conductive copper foil and PET substrate, to obtain a symmetrical all-solid-state M / PA / M supercapacitor with infrared stealth. Example

[0031] This embodiment proposes a specific application based on the above embodiments one and two: Step 1: Preparation of MXene. 1 g LiF was mixed with 30 ml 9M HCl in a polytetrafluoroethylene beaker. The mixture was then continuously stirred at 20℃-70℃ until completely dissolved. 1 g Ti3AlC2 was then stirred at 300 rpm for 36 h to etch the Al layer. Afterward, the mixture was washed multiple times with deionized water until the pH of the solution reached 6. It was then dried under vacuum at 70℃ for 24 h. Finally, it was ultrasonically dispersed in deionized water to obtain a monolayer MXene dispersion.

[0032] Step 2: Preparation of PANI@ANFs. Add 0.2g of PPTA fiber and 0.3g of KOH to a DMSO bottle and stir continuously with a magnetic stirrer for 7 days until the fiber is completely dissolved into a dark red solution. Wash several times with deionized water and then sonicate using a probe to disperse the solution in water, obtaining a 2 mg / ml ANFs aqueous dispersion. Mix 10ml of the ANFs dispersion with 10ml of 1M H2SO4, add 50µl of aniline, and stir with a magnetic stirrer for 30 min. Then transfer the mixture to a refrigerator for polymerization for 5 h. Stirring and polymerization are carried out only at 0-10℃.

[0033] Step 3: Preparation of M / PA / M. 2 ml of MXene, 10 ml of PANI@ANFs, and 2 ml of MXene were vacuum filtered to form sandwich films, denoted as M / PA / M. The film obtained by MXene filtration was denoted as MXene. For the mixed film, the same method was used: first, MXene and PANI@ANFs were magnetically stirred and mixed, then placed in a refrigerator for polymerization for 5 hours, and finally filtered to form a film, denoted as MPA.

[0034] Step 4: Equipment Pretreatment. Before the experiment, the chamber walls were first sanded with fine sandpaper, then wiped with ethanol to prevent impurities from contaminating the film quality. Finally, the substrate was placed on the disk in the center area of ​​the target sputtering region, and the disk rotation speed was set to 30Hz to ensure the uniformity of film deposition.

[0035] Step 5: Coating Pretreatment. The initial vacuum inside the chamber is first pre-evacuated using a mechanical pump. Once the pressure drops to 10.0 Pa, the baffle valve is opened and the molecular pump is started for further fine evacuation, raising the background vacuum of the chamber to 5.0 × 10⁻⁻⁻⁶. 4 After Pa, the working gas is introduced. Once the required vacuum level in the chamber is reached, the heating system is turned on to raise the substrate temperature to the 500 °C required for deposition and hold it at that temperature for 60 minutes to ensure the stability of the vanadium oxide phase generated by reactive sputtering. After the required temperature and vacuum level are reached, 100 sccm of argon and 20 sccm of oxygen are introduced and the gas flow rate is adjusted. Then, the gas supply is turned off and the cycle is repeated several times to remove residual gas. After completion, the DC pulse power supply parameters are set (power 100W, pulse time 1μs, frequency 50 kHz) for 20 minutes of pre-sputtering to clean the target surface and remove impurities such as oxides.

[0036] Step 6: Film Deposition. After pre-sputtering, adjust the angle valve to stabilize the film gauge at 1.0 Pa, open the baffle, and start the sputtering timer. After deposition, turn off the DC pulse power supply and oxygen inlet, and hold the sample at 150 sccm argon for 30 minutes. Then, turn off the heating power and allow the sample to cool slowly to room temperature under argon protection.

[0037] Step 7: Assembly and Molding. Weigh 1 g of PVA and 10 ml of H2SO4 and stir magnetically in a water bath at 50℃-80℃ for 1-3 hours until the solution becomes a clear gel. This yields the PVA / H2SO4 electrolyte. Immerse a piece of non-woven fabric in the resulting solution to obtain a PVA / H2SO4-loaded separator. Cut the coated M / PA / M membrane and assemble them in the following order: substrate, conductive copper foil, conductive silver paste, thin film, separator soaked in electrolyte, conductive silver paste, conductive copper foil, and PET substrate. This yields a symmetrical, all-solid-state M / PA / M supercapacitor with infrared stealth capabilities.

[0038] 1. Cyclic Voltammetry Scan Test See Figure 1 At 2 mV s -1 At a scan rate of cyclic voltammetry (CV), all samples showed a pair of redox peaks near -0.2 V, with peak values ​​at 3.57 mA cm⁻¹. -2 This indicates that it has a higher specific capacitance relative to its thin film, allowing more charge to be stored within it.

[0039] 2. Constant current charge and discharge test See Figure 2 , at 1 mA cm -2 The constant current charge-discharge curves of the M / PA / M50 thin film under current density also show a discharge time of 988.2 s and a maximum voltage of 0.4V.

[0040] This group of experiments served as the control group.

[0041] 3. SEM electron microscopy test See Figure 3 The PA interlayer cross section shows a fiber-layered stacked structure similar to aramid nanofibers (ANFs), but its cross section is rougher than that of ANFs films. In the M / PA / M sample, its overall thickness reaches the maximum value (49.45 μm), which may be due to insufficient PANI content, making it difficult for it to form effective chemical bonds with MXene sheets. Example

[0042] This embodiment proposes a specific application based on the above embodiments one and two: Step 1: Preparation of MXene. 1 g LiF was mixed with 30 ml 9M HCl in a polytetrafluoroethylene beaker. The mixture was then continuously stirred at 20℃-70℃ until completely dissolved. 1 g Ti3AlC2 was then stirred at 300 rpm for 36 h to etch the Al layer. Afterward, the mixture was washed multiple times with deionized water until the pH of the solution reached 6. It was then dried under vacuum at 70℃ for 24 h. Finally, it was ultrasonically dispersed in deionized water to obtain a monolayer MXene dispersion.

[0043] Step 2: Preparation of PANI@ANFs. Add 0.2g of PPTA fiber and 0.3g of KOH to a DMSO bottle and stir continuously with a magnetic stirrer for 7 days until the fiber is completely dissolved into a dark red solution. Wash several times with deionized water and then sonicate using a probe to disperse the solution in water, obtaining a 2 mg / ml ANFs aqueous dispersion. Mix 10ml of the ANFs dispersion with 10ml of 1M H2SO4, add 100µl of aniline, and stir with a magnetic stirrer for 30 min. Then transfer the mixture to a refrigerator for polymerization for 5 h. Stirring and polymerization are carried out only at 0-10℃.

[0044] Step 3: Preparation of M / PA / M. 2 ml of MXene, 10 ml of PANI@ANFs, and 2 ml of MXene were vacuum filtered to form sandwich films, denoted as M / PA / M. The film obtained by MXene filtration was denoted as MXene. For the mixed film, the same method was used: first, MXene and PANI@ANFs were magnetically stirred and mixed, then placed in a refrigerator for polymerization for 5 hours, and finally filtered to form a film, denoted as MPA.

[0045] Step 4: Equipment Pretreatment. Before the experiment, the chamber walls were first sanded with fine sandpaper, then wiped with ethanol to prevent impurities from contaminating the film quality. Finally, the substrate was placed on the disk in the center area of ​​the target sputtering region, and the disk rotation speed was set to 30Hz to ensure the uniformity of film deposition.

[0046] Step 5: Coating Pretreatment. The initial vacuum inside the chamber is first pre-evacuated using a mechanical pump. Once the pressure drops to 10.0 Pa, the baffle valve is opened and the molecular pump is started for further fine evacuation, raising the background vacuum of the chamber to 5.0 × 10⁻⁻⁻⁶. 4 After Pa, the working gas is introduced. Once the required vacuum level in the chamber is reached, the heating system is turned on to raise the substrate temperature to the 500 °C required for deposition and hold it at that temperature for 60 minutes to ensure the stability of the vanadium oxide phase generated by reactive sputtering. After the required temperature and vacuum level are reached, 100 sccm of argon and 20 sccm of oxygen are introduced and the gas flow rate is adjusted. Then, the gas supply is turned off and the cycle is repeated several times to remove residual gas. After completion, the DC pulse power supply parameters are set (power 100W, pulse time 1μs, frequency 50 kHz) for 20 minutes of pre-sputtering to clean the target surface and remove impurities such as oxides.

[0047] Step 6: Film Deposition. After pre-sputtering, adjust the angle valve to stabilize the film gauge at 1.0 Pa, open the baffle, and start the sputtering timer. After deposition, turn off the DC pulse power supply and oxygen inlet, and hold the sample at 150 sccm argon for 30 minutes. Then, turn off the heating power and allow the sample to cool slowly to room temperature under argon protection.

[0048] Step 7: Assembly and Molding. Weigh 1 g of PVA and 10 ml of H2SO4 and stir magnetically in a water bath at 50℃-80℃ for 1-3 hours until the solution becomes a clear gel. This yields the PVA / H2SO4 electrolyte. Immerse a piece of non-woven fabric in the resulting solution to obtain a PVA / H2SO4-loaded separator. Cut the coated M / PA / M membrane and assemble them in the following order: substrate, conductive copper foil, conductive silver paste, thin film, separator soaked in electrolyte, conductive silver paste, conductive copper foil, and PET substrate. This yields a symmetrical, all-solid-state M / PA / M supercapacitor with infrared stealth capabilities.

[0049] 1. Cyclic Voltammetry Scan Test See Figure 4 At 2 mV s -1 At a scan rate of [scan rate], cyclic voltammetry (CV) revealed a pair of redox peaks near -0.2 V for all samples, with peak values ​​at 4.4 mA cm⁻¹. -2 Compared to the control group, it has a larger maximum area of ​​closed curve, indicating that it has a higher specific capacitance.

[0050] 2. Constant current charge and discharge test See Figure 5 , at 1 mA cm -2 The constant current charge-discharge curves of the M / PA / M100 thin film under current density also show a discharge time of 1027 s, which is longer than that of the control group, indicating the highest capacitance, which is consistent with the results shown in the CV plot.

[0051] SEM electron microscopy test See Figure 6 When the PANI content increases to 100%, a tight interfacial bond is formed between the three components, and the surface morphology exhibits a rough feature that is completely different from that of ANFs. This confirms the successful polymerization of PANI and the successful construction of a three-dimensional conductive network structure. At this time, the film thickness is reduced to 32.35 μm. Example

[0052] This embodiment proposes a specific application based on the above embodiments one and two: Step 1: Preparation of MXene. 1 g LiF was mixed with 30 ml 9M HCl in a polytetrafluoroethylene beaker. The mixture was then continuously stirred at 20℃-70℃ until completely dissolved. 1 g Ti3AlC2 was then stirred at 300 rpm for 36 h to etch the Al layer. Afterward, the mixture was washed multiple times with deionized water until the pH of the solution reached 6. It was then dried under vacuum at 70℃ for 24 h. Finally, it was ultrasonically dispersed in deionized water to obtain a monolayer MXene dispersion.

[0053] Step 2: Preparation of PANI@ANFs. Add 0.2g of PPTA fiber and 0.3g of KOH to a DMSO bottle and stir continuously with a magnetic stirrer for 7 days until the fiber is completely dissolved into a dark red solution. Wash several times with deionized water and then sonicate using a probe to disperse the solution in water, obtaining a 2 mg / ml ANFs aqueous dispersion. Mix 10ml of the ANFs dispersion with 10ml of 1M H2SO4, add 150µl of aniline, and stir with a magnetic stirrer for 30 min. Then transfer the mixture to a refrigerator for polymerization for 5 h. Stirring and polymerization are carried out only at 0-10℃.

[0054] Step 3: Preparation of M / PA / M. 2 ml of MXene, 10 ml of PANI@ANFs, and 2 ml of MXene were vacuum filtered to form sandwich films, denoted as M / PA / M. The film obtained by MXene filtration was denoted as MXene. For the mixed film, the same method was used: first, MXene and PANI@ANFs were magnetically stirred and mixed, then placed in a refrigerator for polymerization for 5 hours, and finally filtered to form a film, denoted as MPA.

[0055] Step 4: Equipment Pretreatment. Before the experiment, the chamber walls were first sanded with fine sandpaper, then wiped with ethanol to prevent impurities from contaminating the film quality. Finally, the substrate was placed on the disk in the center area of ​​the target sputtering region, and the disk rotation speed was set to 30Hz to ensure the uniformity of film deposition.

[0056] Step 5: Coating Pretreatment. The initial vacuum inside the chamber is first pre-evacuated using a mechanical pump. Once the pressure drops to 10.0 Pa, the baffle valve is opened and the molecular pump is started for further fine evacuation, raising the background vacuum of the chamber to 5.0 × 10⁻⁻⁻⁶. 4 After Pa, the working gas is introduced. Once the required vacuum level in the chamber is reached, the heating system is turned on to raise the substrate temperature to the 500 °C required for deposition and hold it at that temperature for 60 minutes to ensure the stability of the vanadium oxide phase generated by reactive sputtering. After the required temperature and vacuum level are reached, 100 sccm of argon and 20 sccm of oxygen are introduced and the gas flow rate is adjusted. Then, the gas supply is turned off and the cycle is repeated several times to remove residual gas. After completion, the DC pulse power supply parameters are set (power 100W, pulse time 1μs, frequency 50 kHz) for 20 minutes of pre-sputtering to clean the target surface and remove impurities such as oxides.

[0057] Step 6: Film Deposition. After pre-sputtering, adjust the angle valve to stabilize the film gauge at 1.0 Pa, open the baffle, and start the sputtering timer. After deposition, turn off the DC pulse power supply and oxygen inlet, and hold the sample at 150 sccm argon for 30 minutes. Then, turn off the heating power and allow the sample to cool slowly to room temperature under argon protection.

[0058] Step 7: Assembly and Molding. Weigh 1 g of PVA and 10 ml of H2SO4 and stir magnetically in a water bath at 50℃-80℃ for 1-3 hours until the solution becomes a clear gel. This yields the PVA / H2SO4 electrolyte. Immerse a piece of non-woven fabric in the resulting solution to obtain a PVA / H2SO4-loaded separator. Cut the coated M / PA / M membrane and assemble them in the following order: substrate, conductive copper foil, conductive silver paste, thin film, separator soaked in electrolyte, conductive silver paste, conductive copper foil, and PET substrate. This yields a symmetrical, all-solid-state M / PA / M supercapacitor with infrared stealth capabilities.

[0059] 1. Cyclic Voltammetry Scan Test See Figure 7 At 2 mV s -1 At a scan rate of cyclic voltammetry (CV), all samples showed a pair of redox peaks near -0.2 V, with peak values ​​at 2.84 mA cm⁻¹. -2 Compared to the control group, the area of ​​the closed curve in this group is smaller, indicating that it has a smaller specific capacitance. This suggests that excessive aniline addition reduces its capacitance.

[0060] Constant current charge and discharge test See Figure 8 , at 1 mA cm -2 The constant current charge-discharge curves of the M / PA / M150 film under current density also show a discharge time of 795.1 s, which is shorter than that of the control group. This indicates that the excessive addition of aniline leads to a reduction in discharge time, indicating a smaller capacitance, which is consistent with the results shown in the CV plot.

[0061] 3. SEM electron microscopy test See Figure 9 When the PANI content was further increased to 150, PANI exhibited a distinct aggregated morphology and separated from the ANFs phase, and the film thickness increased to 38.11 μm.

[0062] See Figure 10In summary, the composite film of this invention has a sandwich structure (M / PA / M), consisting of an MXene layer, a PANI@ANFs layer, and another MXene layer from top to bottom. In the PANI@ANFs layer, PANI is attached to the surface of ANFs in a coating structure, forming a stable conductive network. In the application of all-solid-state supercapacitors in temperature sensors, the MXene layer provides long-term energy storage, while the VO2 film provides infrared stealth and temperature response capabilities. Together, they achieve microsecond-level temperature signal response and alarm triggering. During multiple temperature cycles and charge-discharge cycles, the phase transition performance of the VO2 film does not degrade, and the energy storage efficiency of the MXene layer remains high, making it suitable for precision temperature monitoring in industrial production environments.

[0063] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for preparing a nanocomposite material with infrared stealth energy storage, characterized by: At least comprising the following steps: Step 1: Preparation of MXene material to obtain single-layer MXene dispersion liquid; Step 2: Preparation of PANI@ANFs; Step 3: Preparation of M / PA / M using MXene and PANI@ANFs; Step 4: Equipment pretreatment, sandpaper is used to polish the equipment cabin wall, and ethanol is used to wipe it to ensure that there is no impurity pollution, and finally the substrate is placed in the center of the target sputtering to ensure uniform deposition; Step 5: Film coating pretreatment, vacuumize through mechanical pump and molecular pump, and then adjust the temperature for heat preservation, then introduce argon and oxygen, repeatedly exhaust and clean, and then pre-sputter to clean the target surface; Step 6: Thin film deposition, after pre-sputtering, adjust the gas pressure and start sputtering deposition, and after deposition, slowly cool to room temperature in argon environment.

2. The method for preparing the nanocomposite material with infrared stealth energy storage according to claim 1, characterized in that: The step 1 at least comprises the following steps: Mix LiF with 3M-9M HCl in a Teflon beaker, continuously stir the mixed solution at 20℃-70℃ until completely dissolved; Then stir Ti3AlC2 at a speed of 300 rmp for 20 h-40h to etch the AL layer; After that, use deionized water to wash several times until the PH of the mixed solution reaches 6, and dry at 50℃-100℃ in a vacuum environment for 16h~24h; After that, the dried product is dispersed in deionized water by ultrasonic, and single-layer MXene dispersion liquid is obtained.

3. The method according to claim 2, wherein the method is characterized by: The step 2 at least comprises the following steps: First, dissolve PPTA fiber: Add PPTA fiber and potassium hydroxide to dimethyl sulfoxide solution, stir uniformly, use a magnetic stirrer to continuously stir at room temperature for 5-7 days until the PPTA fiber is completely dissolved and the solution turns dark red, after the dissolution is completed, use deionized water to wash several times to remove potassium hydroxide and dimethyl sulfoxide in the solution, in order to ensure complete dispersion, use a probe to ultrasonically treat the solution to make the fiber uniformly dispersed in water, and obtain an aromatic nanofiber water dispersion; Then, initiate polymerization reaction of aniline: Mix the obtained aromatic nanofiber water dispersion with concentrated sulfuric acid, add aniline as a polymerization initiator, stir at 0-10℃ low temperature environment using a magnetic stirrer for 10-45 minutes to ensure uniform distribution of aniline and start polymerization reaction, move the stirring mixture into a refrigerator to polymerize at 0-10℃ environment for 2-5 hours.

4. The method according to claim 3, wherein the method is characterized by: The step 3 at least comprises the following steps: Vacuum filter MXene, PANI@ANFs and MXene in sequence to form a sandwich film, denoted as M / PA / M.

5. The method of claim 4, wherein the method further comprises: The step 4 at least comprises the following steps: Before the experiment, use fine sandpaper to polish the cabin wall; Then use ethanol to wipe to prevent impurity pollution affecting the quality of the film; Finally, place the substrate on the disc in the center of the target sputtering area, set the disc speed to 10Hz-50 Hz to ensure the uniformity of film deposition.

6. The method of claim 5, wherein the method further comprises: The step 5 at least comprises the following steps: The initial vacuum degree inside the cavity is pre-extracted by a mechanical pump, and when the air pressure is reduced to 1.0 Pa-10.0 Pa, the baffle valve is opened to start the molecular pump for further fine extraction, so that the background vacuum degree of the chamber is increased to 3.0x10⁻³ Pa-5.0x10⁻³ Pa 4 After that, the working gas is introduced. After the chamber vacuum reaches the required degree, the heating system is turned on to raise the temperature of the M / PA / M substrate to 200 °C-550 °C required for deposition and keep it for 30-60 minutes to ensure the stability of the vanadium oxide phase generated by reactive sputtering; After the temperature and vacuum reach the required degree, argon and oxygen are introduced and the gas flow is adjusted, then the gas is turned off and the cycle is repeated several times to remove residual gas; After completion, the parameters of the direct current pulse power are set for 5-20 minutes of pre-sputtering to clean the target surface and remove impurities.

7. The method according to claim 6, wherein the method is characterized by: The step 6 at least includes the following steps: After the pre-sputtering is completed, the angle valve is adjusted to stabilize the film gauge at 0.4 Pa-1.2 Pa, the shutter is opened, and the sputtering is started; After the deposition is completed, the direct current pulse power and the oxygen inlet are turned off, and the sample is kept in an argon environment of 30-200 sccm for 20-60 minutes; Then the heating power is turned off, and the sample is slowly cooled to room temperature under argon protection.

8. Use of the nanocomposite with infrared stealth energy storage according to any one of claims 1 to 7, characterized in that: The M / PA / M is used to assemble supercapacitors.

9. Use of a nanocomposite material with infrared stealth energy storage according to claim 8, characterized in that: The step of using the M / PA / M to assemble supercapacitors at least includes the following steps: 1 g-5 g of PVA is weighed and mixed with 5 ml-50 ml of H2SO4 in a water bath at 50-80 °C under magnetic stirring for 1-3 hours until the solution becomes a clear gel, and the PVA / H2SO4 electrolyte is obtained; A piece of non-woven fabric is soaked in the PVA / H2SO4 electrolyte to obtain a PVA / H2SO4-loaded separator; The coated M / PA / M is cut, and then assembled according to the order of substrate, conductive copper foil, conductive silver paste, film, electrolyte-soaked separator, conductive silver paste, conductive copper foil, and PET substrate, and a full-solid M / PA / M symmetric supercapacitor with infrared stealth is obtained.

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