Yellow-green switching self-adaptive electrochromic camouflage system based on green light response and preparation method of yellow-green switching self-adaptive electrochromic camouflage system

Abstract

The invention relates to a yellow-green switching self-adaptive electrochromic camouflage system based on green light response and a preparation method thereof. The yellow-green switching self-adaptive electrochromic camouflage system comprises an electrochromic device and a microcontroller, the electrochromism device is of a sandwich laminated structure and comprises two conductive base materials and an interlayer photoresponse electrochromism gel electrolyte. The electrochromic device senses green light and realizes reversible conversion of yellow / green; the microcontroller processes the light signal and applies a coloring / fading voltage signal. According to the invention, the system design is simplified, the communication efficiency and stability of the camouflage system are improved, the response speed and the self-adaptive capability are remarkably improved, the camouflage effect is optimized, and the method has higher applicability.

Description

Technical Field

[0001] The present invention belongs to the field of photoelectric response / electrochromic technology and adaptive camouflage technology, and particularly relates to a yellow-green switching adaptive electrochromic camouflage system based on green light response and a preparation method thereof. Background Art

[0002] With the widespread application of camouflage technology in military, security, and civilian fields, achieving more intelligent, efficient, and stable camouflage effects has become a hot research topic. Traditional camouflage systems often rely on static color changes or manual adjustments, and are unable to automatically adjust color changes based on ambient light conditions, which to some extent limits their application. While existing electrochromic camouflage systems can achieve color adjustment, most rely on external light sources or manual intervention. Moreover, most systems only have a single response mode and lack flexible adaptive capabilities.

[0003] Electrochromic materials, which can produce significant color changes under the action of an electric field, have application potential in the field of adaptive camouflage. However, existing adaptive electrochromic camouflage systems generally have the following shortcomings: First, traditional adaptive camouflage systems require three modules: sensing, processing, and response, which makes system design and operation relatively complex; second, most electrochromic materials respond strongly to ultraviolet light but weakly to visible light (including green light), making it difficult to achieve a uniform adaptive camouflage effect; third, existing camouflage systems lack efficient response to green light environments. Especially in some specific application scenarios (such as when the background is highly similar to the ambient green light), how to accurately sense and switch the camouflage color tone becomes an urgent problem to be solved.

[0004] Therefore, key technical challenges in the development of electrochromic camouflage systems include maintaining adaptive camouflage while simplifying system design, improving response speed, and achieving precise color switching for specific light sources (such as green light). Existing technologies have not adequately addressed these issues, and innovative materials and system designs are urgently needed to improve the sensitivity, adjustability, and ease of operation of the camouflage effect. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a yellow-green switchable adaptive electrochromic camouflage system based on green light response and its preparation method, aiming to solve the problems that the existing adaptive electrochromic camouflage system is relatively complex in design and operation and the camouflage effect of the system is poor in a green light environment.

[0006] The present invention provides a yellow-green switchable adaptive electrochromic camouflage system based on green light response, comprising an electrochromic device and a microcontroller; the electrochromic device is a sandwich structure, comprising two conductive substrates and a light-responsive electrochromic gel electrolyte interlayer; the electrochromic device senses green light and achieves reversible conversion between yellow and green; the microcontroller processes the light signal and applies a coloring / fading voltage signal.

[0007] Preferably, the photoresponsive electrochromic gel electrolyte comprises photoresponsive nanoparticles, electrochromic small molecules, a hole sacrificial agent, a redox stabilizer, a gel matrix, an ionic liquid and a solvent.

[0008] More preferably, the photoresponsive nanoparticles are cadmium sulfide (CdS).

[0009] More preferably, the electrochromic small molecule includes at least one of ethyl viologen (EtVio) or methyl viologen (MeVio).

[0010] More preferably, the hole sacrificial agent is ethylene glycol (EG).

[0011] More preferably, the redox stabilizer is ferrocene (Fc).

[0012] More preferably, the gel matrix is polyethylene oxide (PEO), and its weight average molecular weight is about 4.5 million to 5.5 million.

[0013] More preferably, the ionic liquid includes at least one of 1-butyl-3-methylimidazolium bistrifluoroimide ([BMIM][NTf2]) or 1-ethyl-3-methylimidazolium bistrifluoroimide ([EMIM][NTf2]).

[0014] More preferably, the solvent includes at least one of propylene carbonate (PC), ethylene carbonate (EC) or diethyl carbonate (DEC).

[0015] Preferably, the conductive substrate includes a front conductive substrate and a back conductive substrate; wherein the front conductive substrate is a transparent conductive material; and the back conductive substrate is a transparent or non-transparent conductive material.

[0016] More preferably, the transparent conductive material includes but is not limited to any one of ITO glass, FTO glass, and ITO-PET film; the non-transparent conductive material includes but is not limited to any one of metal foil, metal film or conductive carbon foil, conductive carbon film, wherein the metal foil or metal film includes but is not limited to any one of Au, Pt, Pd, and Ag.

[0017] Preferably, the electrochromic device is at 60W m -2Green light irradiation produces 0.1~10μAcm -2 The current density signal is displayed, and switches from yellow to dark green when a voltage greater than 1.1 V is applied, and fades back from dark green to yellow when no voltage is applied.

[0018] Preferably, the microcontroller is a commercial single chip microcomputer, which has the ability to identify μA level current signals and output 0-2V voltage signals.

[0019] More preferably, the model of the microcontroller includes but is not limited to STM32L476RG, TI MSP432P401R, Microchip PIC24FJ256GA702, etc.

[0020] The present invention also provides a method for preparing a yellow-green switchable adaptive electrochromic camouflage system based on green light response, comprising the following steps:

[0021] S1. Preparation of Photoresponsive Electrochromic Gel Electrolyte

[0022] The electrochromic small molecule and the redox stabilizer are dissolved in a mixed solution of an ionic liquid and a solvent, a gel matrix is added, and the mixture is heated and stirred to form an electrochromic gel electrolyte. Subsequently, photoresponsive nanoparticles and a hole sacrificial agent are added and uniformly dispersed to prepare a photoresponsive electrochromic gel electrolyte.

[0023] S2. Assembling electrochromic devices

[0024] Injecting the light-responsive electrochromic gel electrolyte prepared in step S1 into the cavity constructed by two conductive substrates, controlling the thickness of the cavity, and sealing the cavity as a whole;

[0025] S3. Connecting the electrochromic device to the microcontroller

[0026] The cathode and anode of the electrochromic device were connected to the ground port (GND) and A0 / A1 port of the microcontroller respectively to obtain a yellow-green switchable adaptive electrochromic camouflage system.

[0027] Preferably, the concentrations of the electrochromic small molecule and the redox stabilizer in the mixed solution of the ionic liquid and the solvent in step S1 are both 18 to 22 mmol L -1 In the photoresponsive electrochromic gel electrolyte, the mass fraction of the gel matrix is 0.8 to 1.2 wt%, the mass fraction of the photoresponsive nanoparticles is 18 to 22 wt%, and the mass fraction of the hole sacrificial agent is 1 to 10 wt%.

[0028] Preferably, in step S2, 0.2-0.3 mm 3M VHB tape is used to control the cavity thickness; UV curing agent is used for overall sealing, and the curing time is 3-5 minutes. During the curing process, direct exposure to the active area of the device is avoided.

[0029] Preferably, the power supply mode of the microcontroller in step S3 includes USB power supply, a small portable power supply or a solar cell.

[0030] The working modes of the yellow-green switchable adaptive electrochromic camouflage system of the present invention include: (a) under the irradiation of 520-570nm green light, the electrochromic device generates a μA-level current signal, and the microcontroller recognizes the signal; (b) the microcontroller outputs a voltage to the electrochromic device, causing it to produce an electrochromic effect, changing from the initial yellow state to dark green; (c) the microcontroller stops outputting the voltage signal, and the electrochromic device undergoes a self-fading reaction, fading from dark green back to yellow.

[0031] Beneficial effects

[0032] (a) Simplified system design: By integrating the sensing module and the response module into the electrochromic device, the present invention simplifies the complex circuits and module connections in the traditional camouflage system, thereby improving the communication efficiency and stability of the system.

[0033] (b) Improving response speed: By using green-light-responsive electrochromic materials and a microcontroller, the present invention can achieve rapid and accurate color switching under green light, significantly improving the response speed and adaptability of the camouflage system.

[0034] (c) Optimizing camouflage effect: The present invention has excellent camouflage ability in green light environment, can accurately sense and switch to the appropriate color tone, solves the problem of poor response to green light environment in the prior art, and has higher stability and applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The crystal structure and micromorphology of the CdS powder in the embodiment of the present invention are shown as follows: (a) XRD pattern and standard PDF card; (b) FTIR transmittance spectrum; (c) SEM image; (d) particle size distribution.

[0036] Figure 2 (a) The electrochemical impedance spectroscopy of the electrochromic device containing different mass fractions of EG in the embodiment of the present invention; (b) The in situ time-current density change curve of the electrochromic device without EG (0 wt.% EG) before green light irradiation and after continuous green light irradiation for 3 h.

[0037] Figure 3Figure 2 shows the photoresponse stability of the electrochromic device containing different mass fractions of EG in the embodiment of the present invention, (a) before green light irradiation and (b) after continuous green light irradiation for 3 h.

[0038] Figure 4 The electrochromic performance of the green-light-responsive yellow-green switchable electrochromic device of the present invention. (a) Visible light reflectance spectra at different voltages (0-2V), with insets showing digital photographs of the bleached (0V) and tinted (1.2V) states; (b) The color reduction mechanism of the device as it changes from bright yellow to dark green; (c) CIE 1976 Lab coordinates corresponding to the bleached and tinted states; (d) In-situ reflectance response spectrum; (e) Tinting efficiency spectrum; (f) In-situ reflectance response spectrum before and after 5000 cycles.

[0039] Figure 5 Schematic diagram of the operating mechanism of the yellow-green switchable adaptive electrochromic camouflage system based on green light response in the present invention: sensing step and response step.

[0040] Figure 6 The adaptive electrochromic camouflage system: (a) the change in photocurrent density in the sensing step; (b) the change in color current density in the response step; (c) a schematic diagram of the device state changes during specific operation and the corresponding physical image. DETAILED DESCRIPTION

[0041] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0042] The reagents and materials used in the following examples are all commercially available: EtVio and MeVio (Sigma-Aldrich), CdCl2 (Shanghai Merck Chemical), organic solvents such as TAA, ammonia, EG, Fc and PC (Shanghai Sinopharm), [BMIM][NTf2] and [EMIM][NTf2] (Shanghai Merck), polymer PEO (BASF), ITO / FTO conductive glass and film (Zhuhai Kaiwei), metal / carbon flakes (Beijing Zhongnuo New Materials).

[0043] Example 1

[0044] In this embodiment, the photoresponsive CdS nanoparticles are prepared by a hydrothermal method, and the specific steps include:

[0045] (a) 1.10 g of cadmium chloride (CdCl2) and 0.451 g of thioacetamide (TAA) were dissolved in a mixture of 20 ml of ammonia water and 130 ml of deionized water, respectively;

[0046] (b) The two solutions were mixed and transferred to a stainless steel autoclave with a PTFE liner and reacted at 160 °C for 48 h.

[0047] (c) After natural cooling, the yellow precipitate was separated by filtration, washed by centrifugation with anhydrous ethanol and deionized water multiple times, and dried to obtain CdS yellow powder.

[0048] like Figure 1 As shown in Figure a, the XRD pattern of the synthesized CdS powder shows characteristic peaks that match the standard cards PDF#77-2306 and PDF#89 0440, namely the cubic zincite structure and the hexagonal beryl structure. The characteristic diffraction peaks corresponding to the (111), (220) and (311) crystal planes of the cubic phase cadmium sulfide, and the (100), (002) and (101) crystal planes of the hexagonal phase are precisely positioned and have sharp peak shapes, which indicates that the CdS powder was successfully synthesized and has good crystallinity. Figure 1 b is the infrared absorption spectrum of CdS powder, 620 cm -1 The peak at 1120 cm is a typical characteristic peak of CdS, which is related to the stretching vibration of the Cd-S bond; -1 The peak is usually associated with the stretching vibration of S=O or CN bond, which also indicates the successful synthesis of CdS powder. The microscopic morphology of CdS powder is shown in Figure 2. Figure 1 As shown in Figure c, CdS has a uniform polyhedral structure, uniform size distribution, clear interface, and good surface flatness, which indicates that cadmium sulfide particles can grow uniformly under hydrothermal synthesis conditions, and each crystal can fully display its polyhedral crystal characteristics. According to the statistical particle size analysis spectrum ( Figure 1 d) It can be concluded that the particle size of CdS powder is about 90 nm.

[0049] Example 2

[0050] Preparation of photoresponsive electrochromic gel electrolytes containing different mass fractions of EG:

[0051] 0.249 g EtVio and 0.074 g Fc were dissolved in a mixed solution of 2 ml [BMIM] [TFSI] and 18 ml PC. The concentrations of EtVio and Fc were both 20 mmol L -1; Add 1wt% PEO and heat with stirring to form an electrochromic gel electrolyte. Subsequently, add CdS (20wt%) and EG (3wt%) prepared in Example 1, and obtain the final electrolyte after mechanical / ultrasonic dispersion. Among them, when the total mass of the electrolyte is 10g, the actual added mass of PEO, CdS and EG are 0.1g, 2.0g and 0.3g respectively. In addition, it is worth noting that the amount of EG added is the optimal ratio after optimization. In order to demonstrate the optimization process, light-responsive electrochromic gel electrolytes containing 0wt%, 1wt% (0.1g), 5wt% (0.5g) and 10wt% (1.0g) EG were also prepared (while the proportion of EG increased, the proportion of the total of the other components decreased).

[0052] Preparation of electrochromic devices corresponding to light-responsive electrochromic gel electrolytes containing different mass fractions of EG:

[0053] The light-responsive electrochromic gel electrolyte prepared in the previous step was injected into a cavity constructed from two sheets of FTO conductive glass. 3M VHB tape was used to control the cavity thickness, and the entire cavity was sealed using a UV curing agent. The 3M VHB tape was 0.2 mm thick and the UV curing time was 5 minutes. During the curing process, avoid direct exposure to the active area of the device.

[0054] To this end, the electrochemical impedance spectroscopy technique was first used to characterize the ionic conductivity of the electrochromic devices corresponding to electrolytes containing different mass fractions of EG. Figure 2 a and the ionic conductivity calculation formula, the ionic conductivities of the electrochromic devices corresponding to the electrolytes containing 0wt%, 1wt%, 3wt%, 5wt% and 10wt% EG are 6.04×10 -4 S cm -1 、6.19×10 -4 S cm -1 , 5.23×10 -4 S cm -1 , 5.19×10 -4 S cm -1 and 4.58×10 -4 S cm -1 The ionic conductivity of the electrochromic devices with 0wt% and 1wt% EG was similar, but the ionic conductivity of the gel gradually decreased with increasing EG content. This phenomenon is mainly due to the fact that the addition of EG increases the viscosity of the gel, further restricting the migration of ions and leading to a decrease in ionic conductivity.

[0055] Figure 2 b is the electrochromic device without EG (0 wt% EG) under the light intensity of 60 W m -2The in-situ photoresponse current curves before and after continuous illumination for 3 hours under 520-570nm green light. The results show that the current density of the device fluctuates under intermittent green light irradiation (light on / light off). When the light source is turned on, the device absorbs light energy, stimulates electron transitions, and generates a photocurrent signal; when the light source is turned off, the electrons return to their original state, and the current density signal tends to 0. This change in current density when the light source is switched on and off proves that even without EG, the device still has the ability to respond to green light. At the same time, in order to further test the photostability of the device, it was placed in a room with a light intensity of 60W m -2 The device was continuously illuminated with 520-570nm green light for 3 hours (all subsequent illumination tests were based on this light intensity), and the photocurrent density change of the device under the switching light source conditions after 3 hours was tested. Figure 2 As shown by the dashed line in (b), after 3 hours of continuous illumination, the photoresponse current of the device is almost unrecognizable. This attenuation may be due to the photocorrosion of CdS.

[0056] Adding hole sacrificial agents is an effective method to improve the photostability of optoelectronic devices containing semiconductor materials. EG has been widely used to improve the performance of optoelectronic devices due to its excellent chemical stability and strong reducing ability. EG can not only effectively capture photogenerated holes, but also stabilize the structure of the material during the reaction process and slow down the occurrence of photoinduced degradation. Figure 3 As shown in a and b, the photoresponse changes of the electrochromic devices corresponding to the electrolytes containing 1wt%, 3wt%, 5wt% and 10wt% EG before and after 3 hours of continuous illumination under 520-570nm green light were characterized, and the decay rate of the photoresponse current density before and after illumination was calculated. For the 1wt% EG-based device, the average photocurrent change before continuous illumination was about 0.45μAcm -2 The average current density change after illumination is 0.07 μA cm -2 For the 3wt% based device, the average photocurrent change before continuous illumination is about 0.69μA cm -2 The average current density change after illumination is 0.25 μA cm -2 For the 5wt% EG-based device, the average photocurrent change before continuous illumination is about 2.76μA cm -2 The average current density change after illumination is 0.66 μA cm -2 For the 10wt% based device, the average photocurrent change before continuous illumination is about 3.05μA cm -2 The average current density change after illumination is 0.87 μA cm -2As can be seen, the attenuation rates of electrochromic devices containing 1wt%, 3wt%, 5wt%, and 10wt% EG were 84%, 64%, 76%, and 71%, respectively. Based on the degree of photocurrent response attenuation and ionic conductivity of devices containing different mass fractions of EG, the optimal EG content was determined to be 3wt% (lowest attenuation rate and higher ionic conductivity).

[0057] Based on the above optimization experiments, the color-changing performance of the electrochromic device containing 3 wt% EG was further characterized. Figure 4 a is the visible light reflectance spectrum of the device at 0-2V. When the applied voltage is less than 0.6V, the reflectance of the device remains unchanged; as the voltage increases, the color of the device gradually deepens, and this change is reflected in the gradual decrease in reflectance. When the voltage reaches 1.1V, the reflectance of the device almost reaches its maximum value. After further increasing the voltage, the reflectance changes slightly and the color of the device hardly changes. Considering that higher voltage can accelerate the color change process, but too high voltage may affect the cycle stability of the device, the coloring voltage is set to 1.2V. At the same time, Figure 4 a shows the effect of the device at 0V (bleached state, bright yellow) and 1.2V (colored state, dark green). The key to the device's ability to achieve yellow-green switching lies in the application of the subtractive effect. Figure 4 As shown in Figure 2 (b), the device without CdS nanoparticles is a transmissive device, transparent and colorless in the bleached state and dark blue in the stained state. This is due to the electrochromic property of EtVio: it changes from colorless to blue. The device with CdS nanoparticles, on the other hand, becomes a reflective device. In the bleached state, the CdS color is bright yellow, while the EtVio remains colorless. During stained state, the EtVio changes from colorless to blue, and the blue EtVio and the bright yellow of the CdS itself are superimposed, resulting in a dark green color.

[0058] In order to more accurately evaluate the color variation range of the device in the bleached and colored states, the [L, a, b] values of the device in the two states were characterized using a colorimeter and compared with the colorimetric values required for military camouflage, such as Figure 4c. The [L, a, b] values of the device in the bleached state are [59.86, 18.39, 39.91], while those in the tinted state are [42.93, 2.12, 12.56]. During this process, the L* value, representing brightness, decreases, indicating that the device absorbs more light and becomes darker during tinting. This change is consistent with the aforementioned reflectivity change. The a value in the tinted state is 2.12, indicating that it is close to neutral in the red-green range (neither green nor red). The b value in the faded state is 39.91, while the b value in the tinted state is 12.56. This indicates that the device exhibits a strong yellow component in the faded state, while in the tinted state, the yellow component is significantly reduced but still tends to be yellow. When the [L, a, b] values of the colored and faded states were compared with two commonly used camouflage colors, YG1247 (Lab: 66, 13.4, 35.9) and YE3559 (Lab: 41, -5.3, 12.8), the chromaticity differences were only 7 and 8, respectively. This indicates that the yellow-green color of the device has potential for application in the field of military camouflage.

[0059] In addition, the coloring / fading time and coloring efficiency of the device were also tested, such as Figure 4 d. When the device reaches 90% of the maximum light modulation range, the coloring and fading times are 2.0s and 2.5s respectively. By measuring the optical density change (ΔOD) under unit charge injection and combining it with the coloring efficiency calculation formula, the coloring efficiency of the device is calculated to be 91cm 2 C -1 ( Figure 4 e). The fast switching speed indicates that the electrochromic device can quickly switch between the coloring and fading states in a short period of time. The high coloring efficiency means that the device can achieve significant optical changes under low charge injection conditions, indicating that it can effectively adjust optical properties under low energy consumption conditions, which is crucial for the development of energy-efficient and environmentally friendly devices.

[0060] Finally, the color switching stability of electrochromic devices is one of the key performance indicators. Figure 4 a, The device has the largest optical modulation range at a wavelength of 605nm. The optical modulation range change of the device before and after 5000 cycles was tested, as shown in Figure 2. Figure 4 As shown in Figure f, the light modulation range is about 29.0% during the initial 100 cycles; after 5000 cycles, the light modulation range remains at 28.4% and the decay rate is only 2%, indicating that the device has good cycle stability and great application potential.

[0061] Example 3

[0062] Construction of a yellow-green switchable adaptive electrochromic camouflage system based on green light response: The optimized green light responsive yellow-green switchable electrochromic device in Example 2 (formula: 10g of light responsive electrochromic gel electrolyte containing 20mmol L -1 EtVio (0.249 g), 20 mmol L -1 The cathode and anode of a composite material (0.074g of Fc, 0.1g of 1wt% PEO, 20wt% CdS, and 0.3g of EG) were connected to the ground and A0 / A1 ports of a microcontroller, respectively. The microcontroller was powered by USB and used computer software to monitor the camouflage system's operation in real time and collect data.

[0063] The system consists of a green-light-responsive yellow-green switchable electrochromic device and a microcontroller, and its operation is divided into two main steps: sensing and response. Figure 5 As shown in the figure, during the sensing phase, the device detects green light illumination, generating a photocurrent signal that is fed into the microcontroller's A0 port. The microcontroller then processes this current signal and responds. During the response phase, the microcontroller supplies the device with the voltage required for coloration, switching it from the bleached state to the colored state. Figure 6 a shows the change in photocurrent density of the device during the switching of the green light source. The results show that the device generated obvious and identifiable photocurrent signals during multiple switching processes. Figure 6 b shows the current density change of the device during multiple yellow / green switching processes driven by a microcontroller, indicating that the device has high electrochromic cycle stability. Figure 6 Figure c further illustrates the color changes of the device during operation of the adaptive camouflage system. The corresponding images show the device's initial state, its state under illumination, the process of the microcontroller driving the device from yellow to green after the illumination is removed, and the process of the device fading back from green to yellow.

[0064] Compared to traditional adaptive camouflage systems, where the sensing and response modules are separate, the electrochromic device in this camouflage system performs both sensing and response functions, simplifying module and circuit connections and improving communication efficiency. This invention provides a new technical approach for the optimized design of adaptive camouflage systems and has significant application value.

Claims

1. A yellow-green switchable adaptive electrochromic camouflage system based on green light response, characterized in that: The invention comprises an electrochromic device and a microcontroller; the electrochromic device is a sandwich structure, comprising two conductive substrates and a light-responsive electrochromic gel electrolyte in an interlayer; the electrochromic device senses green light and realizes reversible conversion between yellow and green; the microcontroller processes the light signal and applies a coloring / fading voltage signal.

2. The yellow-green switchable adaptive electrochromic camouflage system based on green light response according to claim 1 is characterized in that: The photoresponsive electrochromic gel electrolyte comprises photoresponsive nanoparticles, electrochromic small molecules, a hole sacrificial agent, a redox stabilizer, a gel matrix, an ionic liquid and a solvent.

3. The yellow-green switchable adaptive electrochromic camouflage system based on green light response according to claim 2 is characterized in that: The photoresponsive nanoparticles are cadmium sulfide; the electrochromic small molecules include at least one of ethyl viologen or methyl viologen; the hole sacrificial agent is ethylene glycol; the redox stabilizer is ferrocene; the gel matrix is polyethylene oxide, and the weight-average molecular weight is 4.5 million to 5.5 million; the ionic liquid includes at least one of 1-butyl-3-methylimidazolium bistrifluoroimide or 1-ethyl-3-methylimidazolium bistrifluoroimide salt; and the solvent includes at least one of propylene carbonate, ethylene carbonate or diethyl carbonate.

4. The yellow-green switchable adaptive electrochromic camouflage system based on green light response according to claim 1 is characterized in that: The conductive substrate includes a front conductive substrate and a back conductive substrate; wherein the front conductive substrate is a transparent conductive material; and the back conductive substrate is a transparent or non-transparent conductive material.

5. The yellow-green switchable adaptive electrochromic camouflage system based on green light response according to claim 4 is characterized in that: The transparent conductive material includes any one of ITO glass, FTO glass, and ITO-PET film; the non-transparent conductive material includes any one of metal flakes, metal films, or conductive carbon flakes, and conductive carbon films; wherein the metal flakes or metal films include any one of Au, Pt, Pd, and Ag.

6. The yellow-green switchable adaptive electrochromic camouflage system based on green light response according to claim 1 is characterized in that: The electrochromic device is 60W m -2 Green light irradiation produces 0.1-10 μA cm -2 The current density signal is displayed, and switches from yellow to dark green when subjected to a voltage greater than 1.1V, and fades back from dark green to yellow when no voltage is applied; the microcontroller is a commercial single-chip microcomputer with the ability to recognize μA-level current signals and output 0-2V voltage signals.

7. A method for preparing a yellow-green switchable adaptive electrochromic camouflage system based on green light response, comprising the following steps: S1. Preparation of Photoresponsive Electrochromic Gel Electrolyte The electrochromic small molecule and the redox stabilizer are dissolved in a mixed solution of an ionic liquid and a solvent, a gel matrix is added, and the mixture is heated and stirred to form an electrochromic gel electrolyte. Subsequently, photoresponsive nanoparticles and a hole sacrificial agent are added and uniformly dispersed to prepare a photoresponsive electrochromic gel electrolyte. S2. Assembling electrochromic devices Injecting the light-responsive electrochromic gel electrolyte prepared in step S1 into the cavity constructed by two conductive substrates, controlling the thickness of the cavity, and sealing the cavity as a whole; S3. Connecting the electrochromic device to the microcontroller The cathode and anode of the electrochromic device are connected to the ground port and A0 / A1 port of the microcontroller respectively to obtain a yellow-green switchable adaptive electrochromic camouflage system.

8. The method for preparing the yellow-green switchable adaptive electrochromic camouflage system based on green light response according to claim 7, characterized in that: The concentrations of the electrochromic small molecule and the redox stabilizer in the mixed solution of the ionic liquid and the solvent in step S1 are both 18 to 22 mmol L -1 In the photoresponsive electrochromic gel electrolyte, the mass fraction of the gel matrix is 0.8 to 1.2 wt%, the mass fraction of the photoresponsive nanoparticles is 18 to 22 wt%, and the mass fraction of the hole sacrificial agent is 1 to 10 wt%.

9. The method for preparing a yellow-green switchable adaptive electrochromic camouflage system based on green light response according to claim 7, characterized in that: In step S2, 0.2-0.3 mm 3M VHB tape is used to control the cavity thickness; UV curing agent is used for overall sealing, and the curing time is 3-5 minutes. During the curing process, direct exposure to the active area of the device is avoided.

10. The method for preparing a yellow-green switchable adaptive electrochromic camouflage system based on green light response according to claim 7, characterized in that: In step S3, the microcontroller is powered by a USB, a small portable power supply or a solar cell.

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