Phase-change photo-thermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel modified Ni net and preparation method of phase-change photo-thermal hydrophobic anti-icing coating

Abstract

The invention discloses a phase-change photo-thermal hydrophobic anti-icing coating based on a carbon nanotube SiO2 aerogel modified Ni net and a preparation method of the phase-change photo-thermal hydrophobic anti-icing coating, and belongs to the technical field of functional composite materials and active anti-icing. The coating comprises a metal framework substrate with a porous net structure, a composite system of photo-thermal filler and a phase change material is packaged in the metal framework substrate, and the surface of the metal framework substrate is covered with a hydrophobic polymer layer. According to the invention, synergistic interaction of triple functions of photo-thermal triggering, phase change energy storage and hydrophobic protection is innovatively realized. The coating not only can quickly remove ice under illumination, but also can continuously prevent ice under a dark condition by utilizing latent heat stored by the phase change material, so that the time limit is broken through. Meanwhile, the hydrophobic polymer on the outer layer is combined with the interface lubrication effect generated by the internal phase change unit, the ice adhesive force can be remarkably reduced, the deicing process is converted into low-energy-consumption deicing from high-energy-consumption deicing, and finally the efficient, long-acting and energy-saving active anti-icing effect is achieved.

Description

Technical Field

[0001] This invention relates to a phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel modified Ni mesh and its preparation method, belonging to the field of functional composite materials and active anti-icing technology. Background Technology

[0002] In daily production and life, many uncontrollable freezing and icing phenomena can pose serious threats to transportation systems, infrastructure, wind turbines, and other fields, and may even lead to severe socio-economic impacts or disasters. Currently, the main solution is to effectively mitigate snow and ice disasters in engineering applications by using anti-icing coatings. However, current traditional anti-icing technologies suffer from high energy consumption, low efficiency, and reliance on external energy input. In particular, emerging photothermal anti-icing coatings still suffer from low photothermal energy utilization, inability to continuously remove ice, and poor substrate adhesion and mechanical durability. This invention mainly provides a method for preparing an anti-icing coating that can efficiently collect and store light energy, continuously and actively release energy for anti-icing / de-icing under no-light conditions, and simultaneously possesses good mechanical stability.

[0003] Traditional passive anti-icing coatings (such as superhydrophobic coatings or fluid-filled smooth surfaces) typically rely on sophisticated micro / nano rough structures or fluid-retaining polymer networks to achieve anti-icing functionality. However, such structures or networks are prone to physical damage under severe mechanical stress (such as wind and sand erosion, ice crystal expansion, or daily wear), leading to microstructural collapse or rapid lubricant loss, thus causing irreversible degradation of anti-icing performance.

[0004] Most existing photothermal anti-icing coatings can rapidly heat up under sunlight, but once the sunlight stops, their temperature drops rapidly below freezing, thus losing their anti-icing ability. The anti-icing effect of these coatings depends entirely on continuous sunlight and lacks effective energy regulation and storage capabilities. Therefore, they cannot cope with the actual environmental challenges posed by intermittent sunlight, resulting in a significant decrease or even failure of their anti-icing performance, and failing to meet the engineering requirements for all-weather protection.

[0005] Meanwhile, some anti-icing coatings have poor adhesion to metal substrates (such as aircraft skin and wind turbine blades) and are brittle. They are prone to peeling off under harsh conditions such as wind and rain erosion, ice shedding, or mechanical wear, making it difficult to meet the stringent durability requirements of actual engineering applications.

[0006] Therefore, the purpose of this invention is to overcome the shortcomings of existing anti-icing technologies in terms of sustainability, energy consumption, and functionality, and to provide a high-performance active anti-icing coating integrating photothermal conversion, energy storage, and hydrophobic protection, as well as its preparation method. This invention provides a phase change composite material based on a porous Ni mesh framework and carbon nanotube / SiO2 aerogel encapsulation, and combines this with hydrophobic polymer modification via a sol-gel method to prepare a highly efficient, long-lasting, and stable anti-icing coating with multifunctional synergistic effects of photothermal triggering and phase change energy storage. Simultaneously, it provides a simple and reliable preparation method for this coating to solve the technical problems of high energy consumption and poor sustainability in existing anti-icing technologies. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a phase change material / hydrophobic polymer composite anti-icing coating with photothermal triggering de-icing function, prepared by the sol-gel method. It is a multi-layer composite structure, including a metal skeleton substrate with a porous mesh structure, a composite system containing photothermal fillers and phase change materials formed therein by the sol-gel method, and a hydrophobic polymer layer covering the surface of the metal skeleton substrate.

[0008] Meanwhile, this invention provides a method for preparing a phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel-modified Ni mesh.

[0009] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A method for preparing a phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel-modified Ni mesh includes the following steps: Step 1: Pretreatment of the metal mesh skeleton: Cut the porous nickel mesh substrate (surface pore size varies from 200-300 μm, thickness from 0.5-1.5 mm) to the required size. Clean it sequentially with acetone, anhydrous ethanol, and deionized water using ultrasonic cleaning for 8-12 minutes each, and then dry it at 75-85 ℃.

[0010] Step 2: Prepare carbon nanotubes (MWCNTs) with a length of 10-30 μm, purity > 95 wt%, and outer diameter of 10-20 nm. Use carboxylated modified carbon nanotubes (commercially available, such as XFM12 carboxylated multi-walled carbon nanotubes from Xianfeng Nano). Disperse a certain amount of MWCNTs in anhydrous ethanol at a concentration of approximately 0.5-1.5 mg / mL and sonicate (300-500 W for 30-60 minutes) to form a uniform carbon nanotube dispersion.

[0011] Step 3: Under continuous magnetic stirring (at a speed of 280-320 rpm), add tetraethyl orthosilicate (TEOS) dropwise to the carbon nanotube dispersion obtained in Step 2, and continue stirring for 25-35 minutes to ensure uniform mixing. The molar ratio of tetraethyl orthosilicate to anhydrous ethanol should be controlled between 1:4 and 1:8.

[0012] Step 4: Perform the catalytic and hydrolysis process. While continuously stirring, add dropwise a mixed solution of deionized water and ethanol containing a catalyst (such as hydrochloric acid or ammonia), wherein the molar ratio of tetraethyl orthosilicate:ethanol:deionized water:hydrochloric acid is controlled at 1:6:3:0.05. The catalyst is hydrochloric acid or ammonia, with a concentration of 0.05-0.2 M (mol / L).

[0013] After the addition is complete, seal the mouth of the beaker with sealing film and continuously stir magnetically at room temperature (25±2℃) for 180~220rpm for 3.5~4.5 hours to form a uniform and stable carbon nanotube / SiO2 sol (which appears as a slightly transparent dark brown sol).

[0014] Step 5: Immerse the pretreated porous Ni mesh from Step 1 into the sol prepared in Step 4, ensuring the Ni mesh is completely wetted so that the carbon nanotube / SiO2 sol fully fills the macroscopic pores of the porous Ni mesh. Using a dip-coating machine, vertically and smoothly pull the Ni mesh out of the liquid surface at a speed of 1-3 mm / s, so that a uniform sol film can be formed on the Ni mesh surface through surface tension.

[0015] Step Six: Place the Ni mesh with sol on a polytetrafluoroethylene plate and transfer the entire assembly to a sealed container. Allow it to stand and age at room temperature or a slightly higher temperature (e.g., 30-45°C) for 20-28 hours to complete the hydrolysis-condensation reaction and form a wet gel. At this point, the pores of the Ni mesh are filled with the carbon nanotube / SiO2 composite wet gel.

[0016] Step Seven: Next, solvent replacement is performed. The sample aged in Step Six is ​​immersed in anhydrous ethanol for 10-14 hours to shrink and strengthen the gel network. The sample is then removed from the ethanol and immersed in n-hexane for 10-14 hours, replacing the hexane with fresh hexane every 4 hours. The hexane-replaced sample is then placed in a fume hood and allowed to air dry at room temperature for 1-3 hours to allow most of the hexane to evaporate. Finally, the sample is transferred to a forced-air drying oven at 40-60°C and dried for 3-5 hours to ensure complete solvent removal.

[0017] Step 8: Heat the fatty acid phase change material (select a binary eutectic mixture of lauric acid and myristic acid; the phase change temperature can be precisely controlled between 20-35℃ by adjusting the ratio) to a completely molten state (approximately 60-80℃) to obtain a molten PCM liquid. Simultaneously, preheat the aerogel / Ni mesh skeleton obtained in Step 7 at 70-80℃ for 12-18 minutes.

[0018] Step Nine: Quickly immerse the preheated metal skeleton in molten PCM and transfer the entire beaker to a vacuum drying oven, where it is maintained for 30-120 minutes, preferably 50-70 minutes. Utilizing the synergistic effect of vacuum negative pressure (vacuum degree: 0.08-0.1 MPa) and capillary action, the molten PCM is forcibly injected into and fills the nanopores of the aerogel, achieving high loading rate and leak-proof encapsulation. Air is then slowly introduced to restore atmospheric pressure. To achieve a higher encapsulation rate, the cyclic immersion process can be repeated 2-3 times. The sample is then removed, and excess phase change material on the surface is gently wiped away with filter paper. The sample is then cooled to room temperature to obtain a composite skeleton filled with phase change material.

[0019] Step 10: Mix polydimethylsiloxane (PDMS) Part A and Part B at a mass ratio of 10:1. Part A is mainly a mixture of vinyl-terminated PDMS, while Part B, acting as a crosslinking agent and chain extender, is a mixture of polymethylhydrosiloxane and PDMS. Add an appropriate amount (e.g., 1-5 wt%) of SiC particles as a reinforcing filler, dissolve in hexane, and then magnetically stir and ultrasonically disperse to ensure uniform dispersion.

[0020] Step 11: Using spin coating, uniformly coat the mixed solution obtained in Step 10 onto the sample surface obtained in Step 9. The spin coating process consists of two stages: the first stage involves spin coating at 1000-1500 rpm for 15-25 seconds to achieve solution pre-spreading; the second stage involves spin coating at 2000-3000 rpm for 40-60 seconds to control the final film thickness to 20-50 μm. After spin coating, transfer the sample to a conventional oven for further curing. Heat treat at 40-60℃ for 30-60 minutes, then raise the temperature to 80-100℃ for 1-2 hours. Cool in the oven and remove the sample to obtain the finished product.

[0021] In step two, the purpose of using carboxylated modified carbon nanotubes is to enhance their compatibility with ethanol and to enable them to form a stronger interaction with the subsequent SiO2 matrix.

[0022] In step two, pre-dispersion is required. Use a magnetic stirrer to stir for 30 minutes at a speed of 400-500 rpm to initially wet the carbon nanotubes.

[0023] In step two, an ultrasonic cell disruptor is used to break up the carbon nanotube bundles using the cavitation effect, forming a uniform and stable black dispersion, preferably with no visible precipitate after standing for 24 hours.

[0024] In step four, the droplet infusion rate must be strictly controlled to avoid localized excessively rapid hydrolysis and precipitation.

[0025] In step six, a small beaker filled with ethanol can be placed at the bottom of the container to maintain the internal solvent atmosphere and prevent the surface from cracking due to the solvent evaporating too quickly.

[0026] In step eight, the purpose of preheating at 75-80℃ for 12-18 minutes is to reduce the viscosity of the PCM and remove any residual air in the skeleton pores, in preparation for vacuum impregnation.

[0027] The main purpose of adding n-hexane in step ten is to adjust the viscosity and facilitate film formation. The quality of n-hexane used is the same as that of the PDMS prepolymer.

[0028] The application of a smart self-de-icing coating based on photothermal triggering and phase change energy storage (i.e., a phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel modified Ni mesh) on the surface of engineering components, including energy equipment such as wind turbine blades, UAV wings, and power transmission lines, or communication equipment such as communication towers and radar antennas.

[0029] Addressing the technical challenges of existing photothermal anti-icing coatings' strong dependence on continuous light exposure and their susceptibility to failure in the absence of light, as well as the performance degradation caused by leakage of phase change materials during solid-liquid cycling, this invention creatively combines a highly thermally conductive porous metal framework, a photothermal nanofiller / silica composite aerogel, a fatty acid phase change material, and a hydrophobic polymer protective layer. Using a porous Ni mesh as the macroscopic support substrate, and employing carbon nanotube / SiO2 nanoporous aerogel constructed in situ via the sol-gel method as a micro / nano container, the invention leverages the large specific surface area and strong capillary forces to achieve efficient and robust encapsulation of molten fatty acid phase change materials, fundamentally solving the leakage problem. By combining the use of a surface hydrophobic polymer layer (PDMS) and its ingenious "photothermal-phase change-hydrophobic" triple functional synergy design, carbon nanotubes are used to achieve efficient photothermal triggering, phase change materials are used to achieve continuous energy supply and continuous heating in the absence of light, and the low ice adhesion of the hydrophobic layer and the interfacial lubrication effect mediated by the phase change transform "ice melting" into "ice removal". This fundamentally improves the anti-icing efficiency of the anti-icing structure, extends the protection time, and significantly reduces de-icing energy consumption. The preparation method is mature, highly controllable, and can be mass-produced.

[0030] This invention employs a method combining the sol-gel method with vacuum impregnation, which has a clear technical route. By precisely controlling the sol components, aging conditions, and impregnation parameters, it is possible to stably and reliably prepare a high-performance photothermal triggered self-de-icing coating.

[0031] Compared with the prior art, the beneficial effects of the present invention are: The core advantage of this invention lies in solving two key technical bottlenecks: the dependence of photothermal anti-icing technology on continuous illumination and the easy leakage of phase change materials. The carbon nanotube / SiO2 composite aerogel constructed within a porous nickel mesh using the sol-gel method can achieve rapid photothermal response through the carbon nanotubes, and its three-dimensional pores can firmly lock the phase change material through capillary forces, ensuring the structural stability and durability of the coating during long-term phase change cycles.

[0032] Building upon this foundation, this invention innovatively achieves a synergistic effect of three functions: photothermal triggering, phase change energy storage, and hydrophobic protection. The coating not only rapidly de-ices under light but also utilizes the latent heat stored in the phase change material for continuous anti-icing in the absence of light, overcoming time limitations. Simultaneously, the combination of the hydrophobic polymer on the outer layer and the interfacial lubrication effect generated by the internal phase change unit significantly reduces ice adhesion, transforming the de-icing process from high-energy-consuming "ice melting" to low-energy-consuming "ice removal," ultimately achieving a highly efficient, long-lasting, and energy-saving active anti-icing effect. Furthermore, its preparation process is mature and controllable, possessing the potential for large-scale application. Attached Figure Description

[0033] Figure 1 Here is an SEM image of the coating from Example 1; Figure 2 These are magnified optical photographs of Example 1 and Comparative Example 2. Figure 3 It is the static water contact angle; Figure 4 These are surface morphology photographs and surface roughness data of Example 1 and Comparative Example 2; Figure 5 These are the results of delayed icing tests on supercooled droplets on the surfaces of different samples; Figure 6 It represents the temperature change trajectory of different samples during the heating and cooling processes. Detailed Implementation

[0034] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The following embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0035] Example 1 A method for preparing a phase change material / hydrophobic polymer composite anti-icing coating with photothermal triggered de-icing function based on the sol-gel method includes the following steps: 1. Cut the porous nickel mesh substrate to the required size of 100mm × 100mm × 1.0mm, with a surface pore diameter in the range of 200-300 μm and an internal porosity calculated to be approximately 89%. This achieves a balance between ensuring high porosity and sufficient mechanical strength. Perform ultrasonic cleaning sequentially with acetone, anhydrous ethanol, and deionized water for 10 minutes each, then dry at 80℃ for later use.

[0036] 2. A certain amount of carboxylated modified multi-walled carbon nanotubes (MWCNTs) were dispersed in anhydrous ethanol. 0.1 g of MWCNTs was added to 100 mL of anhydrous ethanol, with a concentration of about 1 mg / mL. The mixture was then subjected to ultrasonic treatment (ultrasonic power 400 W, time 45 minutes) to form a uniform carbon nanotube dispersion.

[0037] 3. Based on the above 100 mL carbon nanotube ethanol dispersion, under continuous magnetic stirring (at a speed of 300 rpm), tetraethyl orthosilicate (TEOS) is slowly added dropwise to the carbon nanotube dispersion obtained in step two, and the mixture is stirred continuously for 30 minutes to ensure uniform mixing. The molar ratio of tetraethyl orthosilicate to ethanol is controlled at 1:5.

[0038] 4. While continuously stirring, add dropwise a mixed solution of deionized water and ethanol containing a catalyst (0.1M hydrochloric acid), wherein the molar ratio of tetraethyl orthosilicate:ethanol:deionized water:hydrochloric acid is controlled at 1:6:3:0.05. After the addition is complete, seal the beaker with sealing film and continuously stir magnetically at 200 rpm for 4 hours at room temperature to form a homogeneous and stable carbon nanotube / SiO2 sol (appearing as a slightly transparent dark brown sol).

[0039] 5. Immerse the pretreated porous Ni mesh from step 1 into the carbon nanotube / SiO2 sol prepared in step 4, ensuring the Ni mesh is completely wetted so that the carbon nanotube / SiO2 sol fully fills the macroscopic pores of the porous Ni mesh. Using a dip-coating machine, vertically and smoothly pull the Ni mesh out of the liquid surface at a speed of 2 mm / s, so that it forms a uniform sol film on the Ni mesh surface through surface tension.

[0040] 6. Place the Ni mesh with sol on a polytetrafluoroethylene (PTFE) plate and transfer the entire assembly to a sealed container. Allow it to age at 40°C for 24 hours to complete the hydrolysis-condensation reaction and form a wet gel. At this point, the pores of the Ni mesh are filled with the carbon nanotube / SiO2 composite wet gel.

[0041] 7. Subsequently, solvent replacement was performed. The sample aged in step 6 was immersed in anhydrous ethanol for 12 hours to shrink and strengthen the gel network. The sample was then removed from the ethanol and immersed in n-hexane for 12 hours, with fresh n-hexane replaced every 4 hours. The sample after n-hexane replacement was then placed in a fume hood and allowed to air dry at room temperature for 2 hours to allow most of the n-hexane to evaporate. The sample was then transferred to a 50°C forced-air drying oven and dried for 4 hours to ensure complete solvent removal.

[0042] 8. The fatty acid phase change material (a binary eutectic mixture of lauric acid and myristic acid, with a phase change temperature of approximately 25°C) is heated in an oven at 75°C for 30 minutes to obtain a phase change material solution (PCM). Simultaneously, the aerogel / Ni mesh skeleton obtained in step 7 is preheated at 75°C for 15 minutes.

[0043] 9. Rapidly immerse the preheated metal framework in molten PCM solution. This step requires a sufficient volume of PCM solution, ensuring it significantly exceeds the total pore volume of the porous framework. Transfer the entire beaker to a vacuum drying oven and maintain this position for 60 minutes. Utilizing the synergistic effect of vacuum pressure (0.09 MPa) and capillary action, the molten PCM solution is forcibly injected into and fills the nanopores of the aerogel, achieving high loading rate and leak-proof encapsulation. Air is then slowly introduced to restore atmospheric pressure. To achieve an even higher encapsulation rate, the immersion process is repeated twice. The sample is then removed, and excess phase change material is gently wiped off with filter paper. The sample is then cooled to room temperature to obtain a composite framework filled with phase change material.

[0044] 10. Weigh PDMS prepolymer (Part A) and curing agent (Part B) into a glass beaker at a mass ratio of 10:1, and stir magnetically for 2 minutes at a speed of approximately 100 rpm. Add SiC nanoparticles, accounting for 3 wt% of the total mass of PDMS. Add an equal mass of n-hexane to dilute the PDMS prepolymer. Then, stir magnetically at 400 rpm for 30 minutes, and then transfer to an ultrasonic cleaner (power set to 100W) for 20 minutes of ultrasonic treatment to obtain a uniform, translucent, milky white suspension.

[0045] 11. Using spin coating, uniformly coat the mixed solution obtained in step 10 onto the sample surface obtained in step 9. The spin coating process consists of two stages: the first stage involves spin coating at 1200 rpm for 20 seconds to achieve solution pre-spreading; the second stage involves spin coating at 2500 rpm for 50 seconds to control the final film thickness at 35 μm. After spin coating, transfer the sample to a conventional oven for further curing. Heat treat at 40℃ for 30 minutes, then raise the temperature to 85℃ for 60 minutes, cool with the oven, and remove the sample to obtain the finished product.

[0046] This embodiment provides a phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel-modified Ni mesh, comprising a metal skeleton substrate with a porous mesh structure, an encapsulated composite system containing photothermal fillers and phase change materials formed therein by a sol-gel method, and a hydrophobic polymer layer covering the surface of the metal skeleton substrate.

[0047] Specifically, this embodiment presents a phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel-modified Ni mesh, which has a porous metal skeleton with a porosity of 85-95%, a SiO2 aerogel layer doped with photothermal nanofillers formed inside and on the surface of the metal skeleton by a sol-gel method, a fatty acid phase change material encapsulated in the nanopores of the SiO2 aerogel by vacuum impregnation, together forming a photothermal conversion and energy storage unit, and a hydrophobic polymer protective layer covering the outermost layer.

[0048] This embodiment describes the application of a phase change photothermal hydrophobic and anti-icing coating based on carbon nanotube SiO2 aerogel-modified Ni mesh on the surface of engineering components, including wind turbine blades, power transmission lines, UAV wings, communication towers, and radar antennas.

[0049] Figure 1 SEM images from Example 1 are provided. Figure 1 As shown in (a), the surface is generally smooth and flat, without obvious cracks, pores, or other defects. SiC fibers are visible on the coating surface, appearing as short rods with relatively uniform diameters. Most of the SiC rod-shaped fibers are covered by PDMS and are uniformly distributed within the PDMS matrix, without agglomeration. Figure 1 As shown in (b), the cross-sectional morphology of Example 1 shows irregularly distributed pores with a size of approximately 3 to 5 µm. In contrast, the surface morphology of Comparative Examples 1 and 3 is not significantly different from that of Example 1.

[0050] Figure 2 Partially magnified optical photographs of Example 1 and Comparative Example 2 are provided. As shown in the figure, the surface of Example 1 (…) Figure 2 (a) has a SiC-modified PDMS matrix covering the surface, which appears smooth and uniform, without any visible cracks, bubbles, or particle agglomerates. In contrast, the surface of Comparative Example 2 ( Figure 2 (b) A well-organized mesh structure of the porous nickel mesh can be observed, with smaller pores on the mesh. At this point, the SiO2 aerogel has uniformly coated the surface of the frame, and a thin, uniform sol film can be observed on the surface. Meanwhile, the sample still feels dry to the touch, with no oily seepage, indicating that the phase change material is effectively encapsulated and leak-free.

[0051] Figure 3 Example 1 is given. Figure 3 (a) and Comparative Example 1-( Figure 3 (b), Comparative Example 2-( Figure 3 (c), Comparative Example 3-( Figure 3 (d) Static water contact angle. As Example 1, when a PDMS+SiC coating was added to the surface, the water contact angle was 126.3 ± 2.2°, with a contact angle hysteresis of approximately 5.6°. Comparative Examples 1 and 3 showed no significant difference from Example 1. Comparative Example 1 had a water contact angle of 121.1 ± 1.9° with a contact angle hysteresis of approximately 5.9°, while Comparative Example 3 had a water contact angle of 120.9 ± 1.9° with a contact angle hysteresis of approximately 6.1°. Comparative Example 2, lacking a hydrophobic coating, exhibited a three-dimensional cross-linked structure. The rough surface structure improved hydrophobicity, resulting in a water contact angle of 131.6 ± 2.3°, but a higher contact angle hysteresis of 15.1°. Therefore, the addition of a hydrophobic surface layer helps to construct a more uniform and stable composite structure. In this state, the three-phase contact line of the water droplet can easily move at the tips of these protrusions, resulting in a lower contact angle hysteresis.

[0052] Figure 4 (a) and Figure 4 (b) Surface morphology photographs and surface roughness data of Example 1 and Comparative Example 2 are given. In Example 1, when a PDMS+SiC coating is added to the surface, the surface is smooth and flat, and its surface roughness is approximately 3.2 ± 0.2 μm; the porous nickel mesh of Comparative Example 2 has a regular mesh structure. Its surface roughness is approximately 21.3 ± 3.1 μm.

[0053] Figure 5 The results of delayed freezing tests on supercooled droplets on different sample surfaces show that the freezing time of the droplet on the surface of Comparative Example 2 was the shortest, at 72 ± 2.1 s. This is because the absence of a hydrophobic coating on its surface allows the contact with the porous Ni mesh framework to increase its thermal conductivity, accelerating the absorption of heat by the supercooled droplet. Comparative Example 3 showed a delayed freezing time of 284 ± 5.9 s, as it had a PDMS / SiC composite hydrophobic coating. The low surface energy composition of this surface layer reduced the number of heterogeneous nucleation sites and effectively suppressed ice crystal formation. The delayed freezing time of Example 1 was 411 ± 8.1 s. Firstly, its hydrophobic properties are improved, thereby reducing the contact area between the supercooled droplets and the coating, decreasing the heat exchange efficiency, and delaying the occurrence of icing. Secondly, due to the photothermal phase change energy storage mechanism, the carbon nanotubes in the coating can convert the previously absorbed light energy back into heat energy. Through the characteristics of melting heat absorption and solidification heat release, it continuously releases latent heat in the absence of light, actively heating the surface and preventing the supercooled droplets from reaching the conditions for icing, thus effectively delaying icing for a long time.

[0054] Figure 6 To illustrate the temperature change trajectories of different samples during heating and cooling, the coated samples were placed on a constant-temperature plate (48 ℃). For Comparative Example 1, its temperature rapidly increased from 15.0 ℃ to 45 ℃ within 28 seconds when heated; however, when placed on a constant-temperature plate (14 ℃), the coating temperature rapidly decreased to 14 ℃. In contrast, Comparative Example 3 exhibited a slower heating and cooling rate, with a significantly longer time required to reach equilibrium temperature. Example 1, on the other hand, showed a slower heating and cooling rate compared to Comparative Example 3, and a plateau appeared around 22 ℃, indicating its ability to control a large amount of heat and possessing good temperature control characteristics.

[0055] Example 2 A method for preparing a phase change material / hydrophobic polymer composite anti-icing coating with photothermal triggered de-icing function based on the sol-gel method includes the following steps: 1. Cut the porous nickel mesh substrate to the required size of 100mm × 100mm × 1.0mm, with a surface pore diameter in the range of 200-300 μm and an internal porosity calculated to be approximately 89%. This achieves a balance between ensuring high porosity and sufficient mechanical strength. Perform ultrasonic cleaning sequentially with acetone, anhydrous ethanol, and deionized water for 8 minutes each, then dry at 75 ℃ before use.

[0056] 2. A certain amount of carboxylated modified multi-walled carbon nanotubes (MWCNTs) were dispersed in anhydrous ethanol. 0.05 g of MWCNTs was added to 100 mL of anhydrous ethanol, with a concentration of about 0.5 mg / mL. The mixture was then subjected to ultrasonic treatment (ultrasonic power 300 W, time 30 minutes) to form a uniform carbon nanotube dispersion.

[0057] 3. Based on the above 100 mL carbon nanotube ethanol dispersion, under continuous magnetic stirring (speed maintained at 280 rpm), tetraethyl orthosilicate (TEOS) is slowly added dropwise to the carbon nanotube dispersion obtained in step two, and the mixture is stirred continuously for 25 minutes to ensure uniform mixing. The molar ratio of tetraethyl orthosilicate to ethanol is controlled at 1:4.

[0058] 4. While continuously stirring, add dropwise a mixed solution of deionized water and ethanol containing a catalyst (0.05M hydrochloric acid), wherein the molar ratio of tetraethyl orthosilicate:ethanol:deionized water:hydrochloric acid is controlled at 1:6:3:0.05. After the addition is complete, seal the beaker with sealing film and continuously stir magnetically at 180 rpm for 3.5 hours at room temperature to form a homogeneous and stable carbon nanotube / SiO2 sol (appearing as a slightly transparent dark brown sol).

[0059] 5. Immerse the pretreated porous Ni mesh from step 1 into the carbon nanotube / SiO2 sol prepared in step 4, ensuring the Ni mesh is completely wetted so that the carbon nanotube / SiO2 sol fully fills the macroscopic pores of the porous Ni mesh. Using a dip-coating machine, vertically and smoothly pull the Ni mesh out of the liquid surface at a speed of 1 mm / s, so that a uniform sol film can be formed on the surface of the Ni mesh through surface tension.

[0060] 6. Place the Ni mesh with sol on a polytetrafluoroethylene (PTFE) plate and transfer the entire assembly to a sealed container. Allow it to stand at 30°C for 20 hours to complete the hydrolysis-condensation reaction, forming a wet gel. At this point, the pores of the Ni mesh are filled with the carbon nanotube / SiO2 composite wet gel.

[0061] 7. Subsequently, solvent replacement was performed. The sample aged in step 6 was immersed in anhydrous ethanol for 10 hours to shrink and strengthen the gel network. The sample was then removed from the ethanol and immersed in n-hexane for 10 hours, with fresh n-hexane replaced every 4 hours. The sample after n-hexane replacement was then placed in a fume hood and allowed to air dry at room temperature for 1 hour to allow most of the n-hexane to evaporate. The sample was then transferred to a 40°C forced-air drying oven and dried for 3 hours to ensure complete removal of the solvent.

[0062] 8. The fatty acid phase change material (a binary eutectic mixture of lauric acid and myristic acid, with a phase change temperature of approximately 20°C) is heated in an oven at 60°C for 30 minutes to obtain a phase change material solution (PCM). Simultaneously, the aerogel / Ni mesh skeleton obtained in step 7 is preheated at 70°C for 12 minutes.

[0063] 9. Rapidly immerse the preheated metal framework in molten PCM solution. This step requires a sufficient volume of PCM solution, ensuring it significantly exceeds the total volume of the porous framework pores. Transfer the entire beaker to a vacuum drying oven and maintain this position for 50 minutes. Utilizing the synergistic effect of vacuum pressure (0.08 MPa) and capillary action, forcibly inject and fill the nanopores of the aerogel with the molten PCM solution, achieving high loading rate and leak-proof encapsulation. Then, slowly introduce air to restore atmospheric pressure. To achieve an even higher encapsulation rate, repeat the immersion process three times. Afterward, remove the sample, gently wipe away excess phase change material with filter paper, and cool to room temperature to obtain a composite framework filled with phase change material.

[0064] 10. Weigh PDMS prepolymer (Part A) and curing agent (Part B) into a glass beaker at a mass ratio of 10:1, and stir magnetically for 1 minute at a speed of approximately 80 rpm. Add SiC nanoparticles, accounting for 1 wt% of the total mass of PDMS. Add an equal mass of n-hexane to dilute the PDMS prepolymer. Then, stir magnetically at 300 rpm for 20 minutes, and then transfer to an ultrasonic cleaner (power set to 200W) for 15 minutes of ultrasonic treatment to obtain a uniform, translucent, milky white suspension.

[0065] 11. Using spin coating, uniformly coat the mixed solution obtained in step 10 onto the sample surface obtained in step 9. The spin coating process consists of two stages: the first stage involves spin coating at 1000 rpm for 15 seconds to achieve pre-spreading of the solution; the second stage involves spin coating at 2000 rpm for 40 seconds to control the final film thickness to approximately 20 μm. After spin coating, transfer the sample to a conventional oven for further curing. Heat treat at 50℃ for 45 minutes, then raise the temperature to 80℃ for 90 minutes. Cool in the oven and remove the sample to obtain the finished product.

[0066] This embodiment presents a phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel modified Ni mesh, comprising a metal skeleton substrate with a porous mesh structure, a composite system of photothermal filler and phase change material encapsulated inside the metal skeleton substrate, and a hydrophobic polymer layer covering the surface of the metal skeleton substrate.

[0067] The phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel modified Ni mesh in this embodiment has a water contact angle of 125.6±1.8°, a contact angle hysteresis of 5.7°, and a delayed freezing time of 410±6.2s.

[0068] This embodiment describes the application of a phase change photothermal hydrophobic and anti-icing coating based on carbon nanotube SiO2 aerogel-modified Ni mesh on the surface of engineering components, including wind turbine blades, power transmission lines, UAV wings, communication towers, and radar antennas.

[0069] Example 3 A method for preparing a phase change material / hydrophobic polymer composite anti-icing coating with photothermal triggered de-icing function based on the sol-gel method includes the following steps: 1. Cut the porous nickel mesh substrate to the required size of 100mm × 100mm × 1.0mm, with a surface pore diameter in the range of 200-300 μm and an internal porosity calculated to be approximately 89%. This achieves a balance between ensuring high porosity and sufficient mechanical strength. Perform ultrasonic cleaning sequentially with acetone, anhydrous ethanol, and deionized water for 12 minutes each, then dry at 85°C for later use.

[0070] 2. A certain amount of carboxylated modified multi-walled carbon nanotubes (MWCNTs) were dispersed in anhydrous ethanol. 0.15 g of MWCNTs was added to 100 mL of anhydrous ethanol, with a concentration of about 1.5 mg / mL. The mixture was then subjected to ultrasonic treatment (ultrasonic power 500 W, time 60 minutes) to form a uniform carbon nanotube dispersion.

[0071] 3. Based on the above 100 mL carbon nanotube ethanol dispersion, under continuous magnetic stirring (at a speed of 320 rpm), tetraethyl orthosilicate (TEOS) is slowly added dropwise to the carbon nanotube dispersion obtained in step two, and the mixture is stirred continuously for 35 minutes to ensure uniform mixing. The molar ratio of tetraethyl orthosilicate to ethanol is controlled at 1:8.

[0072] 4. While continuously stirring, add dropwise a mixed solution of deionized water and ethanol containing a catalyst (0.2M hydrochloric acid), wherein the molar ratio of tetraethyl orthosilicate:ethanol:deionized water:hydrochloric acid is controlled at 1:6:3:0.05. After the addition is complete, seal the beaker with sealing film and continuously stir magnetically at room temperature for 4.5 hours at a stirring speed of 220 rpm to form a homogeneous and stable carbon nanotube / SiO2 sol (appearing as a slightly transparent dark brown sol).

[0073] 5. Immerse the pretreated porous Ni mesh from step 1 into the carbon nanotube / SiO2 sol prepared in step 4, ensuring the Ni mesh is completely wetted so that the carbon nanotube / SiO2 sol fully fills the macroscopic pores of the porous Ni mesh. Using a dip-coating machine, vertically and smoothly pull the Ni mesh out of the liquid surface at a speed of 3 mm / s, so that a uniform sol film can be formed on the surface of the Ni mesh through surface tension.

[0074] 6. Place the Ni mesh with sol on a polytetrafluoroethylene (PTFE) plate and transfer the entire assembly to a sealed container. Allow it to age at 45°C for 28 hours to complete the hydrolysis-condensation reaction and form a wet gel. At this point, the pores of the Ni mesh are filled with the carbon nanotube / SiO2 composite wet gel.

[0075] 7. Subsequently, solvent replacement was performed. The sample aged in step 6 was immersed in anhydrous ethanol for 14 hours to shrink and strengthen the gel network. The sample was then removed from the ethanol and immersed in n-hexane for 14 hours, with fresh n-hexane replaced every 4 hours. The sample after n-hexane replacement was then placed in a fume hood and allowed to air dry at room temperature for 3 hours to allow most of the n-hexane to evaporate. The sample was then transferred to a 60°C forced-air drying oven and dried for 5 hours to ensure complete solvent removal.

[0076] 8. The fatty acid phase change material (a binary eutectic mixture of lauric acid and myristic acid, with a phase change temperature of approximately 35°C) is heated in an oven at 80°C for 35 minutes to obtain a phase change material solution (PCM). Simultaneously, the aerogel / Ni mesh skeleton obtained in step 7 is preheated at 80°C for 18 minutes.

[0077] 9. Rapidly immerse the preheated metal framework in molten PCM solution. This step requires a sufficient volume of PCM solution, ensuring it significantly exceeds the total volume of the porous framework pores. Transfer the entire beaker to a vacuum drying oven and maintain this position for 120 minutes. Utilizing the synergistic effect of vacuum pressure (0.1 MPa) and capillary action, the molten PCM solution is forcibly injected into and fills the nanopores of the aerogel, achieving high loading rate and leak-proof encapsulation. Air is then slowly introduced to restore atmospheric pressure. To achieve an even higher encapsulation rate, the immersion process is repeated three times. The sample is then removed, and excess phase change material is gently wiped off with filter paper. The sample is then cooled to room temperature to obtain a composite framework filled with phase change material.

[0078] 10. Weigh PDMS prepolymer (Part A) and curing agent (Part B) into a glass beaker at a mass ratio of 10:1, and stir magnetically for 3 minutes at a speed of approximately 120 rpm. Add SiC nanoparticles, accounting for 5 wt% of the total mass of PDMS. Add an equal mass of n-hexane to dilute the PDMS prepolymer. Then, stir magnetically at 500 rpm for 40 minutes, and then transfer to an ultrasonic cleaner (power set to 400W) for 25 minutes of ultrasonic treatment to obtain a uniform, translucent, milky white suspension.

[0079] 11. Using spin coating, uniformly coat the mixed solution obtained in step 10 onto the sample surface obtained in step 9. The spin coating process consists of two stages: the first stage involves spin coating at 1500 rpm for 25 seconds to achieve pre-spreading of the solution; the second stage involves spin coating at 3000 rpm for 60 seconds to control the final film thickness to approximately 50 μm. After spin coating, transfer the sample to a conventional oven for further curing. Heat treat at 60℃ for 60 minutes, then raise the temperature to 100℃ for 120 minutes. Cool in the oven and remove the sample to obtain the finished product.

[0080] This embodiment presents a phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel modified Ni mesh, comprising a metal skeleton substrate with a porous mesh structure, a composite system of photothermal filler and phase change material encapsulated inside the metal skeleton substrate, and a hydrophobic polymer layer covering the surface of the metal skeleton substrate.

[0081] The phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel modified Ni mesh in this embodiment has a water contact angle of 126.8±2.1°, a contact angle hysteresis of 5.6°, and a delayed freezing time of 413±7.3s.

[0082] This embodiment describes the application of a phase change photothermal hydrophobic and anti-icing coating based on carbon nanotube SiO2 aerogel-modified Ni mesh on the surface of engineering components, including wind turbine blades, power transmission lines, UAV wings, communication towers, and radar antennas.

[0083] Example 4 A method for preparing a phase change material / hydrophobic polymer composite anti-icing coating with photothermal triggered de-icing function based on the sol-gel method includes the following steps: 1. Cut the porous nickel mesh substrate to the required size of 100mm × 100mm × 1.0mm, with a surface pore diameter in the range of 200-300 μm and an internal porosity calculated to be approximately 89%. This achieves a balance between ensuring high porosity and sufficient mechanical strength. Perform ultrasonic cleaning sequentially with acetone, anhydrous ethanol, and deionized water for 9 minutes each, then dry at 80℃ for later use.

[0084] 2. A certain amount of carboxylated modified multi-walled carbon nanotubes (MWCNTs) were dispersed in anhydrous ethanol. 0.15 g of MWCNTs was added to 100 mL of anhydrous ethanol, with a concentration of about 1.5 mg / mL. The mixture was then subjected to ultrasonic treatment (ultrasonic power 450 W, time 60 minutes) to form a uniform carbon nanotube dispersion.

[0085] 3. Based on the above 100 mL carbon nanotube ethanol dispersion, under continuous magnetic stirring (at a speed of 310 rpm), tetraethyl orthosilicate (TEOS) is slowly added dropwise to the carbon nanotube dispersion obtained in step two, and the mixture is stirred continuously for 30 minutes to ensure uniform mixing. The molar ratio of tetraethyl orthosilicate to ethanol is controlled at 1:8.

[0086] 4. During continuous stirring, a mixed solution of deionized water and ethanol containing a catalyst (0.2M ammonia) was added dropwise, with the molar ratio of tetraethyl orthosilicate:ethanol:deionized water:ammonia controlled at 1:6:3:0.05. After the addition was complete, the beaker was sealed with sealing film and continuously magnetically stirred at 210 rpm for 4.0 hours at room temperature to form a homogeneous and stable carbon nanotube / SiO2 sol (appearing as a slightly transparent dark brown sol).

[0087] 5. Immerse the pretreated porous Ni mesh from step 1 into the carbon nanotube / SiO2 sol prepared in step 4, ensuring the Ni mesh is completely wetted so that the carbon nanotube / SiO2 sol fully fills the macroscopic pores of the porous Ni mesh. Using a dip-coating machine, vertically and smoothly pull the Ni mesh out of the liquid surface at a speed of 2 mm / s, so that it forms a uniform sol film on the Ni mesh surface through surface tension.

[0088] 6. Place the Ni mesh with sol on a polytetrafluoroethylene (PTFE) plate and transfer the entire assembly to a sealed container. Allow it to stand at 35°C for 26 hours to complete the hydrolysis-condensation reaction, forming a wet gel. At this point, the pores of the Ni mesh are filled with the carbon nanotube / SiO2 composite wet gel.

[0089] 7. Subsequently, solvent replacement was performed. The sample aged in step 6 was immersed in anhydrous ethanol for 12 hours to shrink and strengthen the gel network. The sample was then removed from the ethanol and immersed in n-hexane for 14 hours, with fresh n-hexane replaced every 4 hours. The sample after n-hexane replacement was then placed in a fume hood and allowed to air dry at room temperature for 1.5 hours to allow most of the n-hexane to evaporate. The sample was then transferred to a 45°C forced-air drying oven and dried for 3.5 hours to ensure complete removal of the solvent.

[0090] 8. The fatty acid phase change material (a binary eutectic mixture of lauric acid and myristic acid, with a phase change temperature of approximately 30°C) is heated in an oven at 80°C for 30 minutes to obtain a phase change material solution (PCM). Simultaneously, the aerogel / Ni mesh skeleton obtained in step 7 is preheated at 80°C for 15 minutes.

[0091] 9. Rapidly immerse the preheated metal framework in molten PCM solution. This step requires a sufficient volume of PCM solution, ensuring it significantly exceeds the total volume of the porous framework pores. Transfer the entire beaker to a vacuum drying oven and maintain this position for 30 minutes. Utilizing the synergistic effect of vacuum pressure (0.1 MPa) and capillary action, forcibly inject and fill the nanopores of the aerogel with the molten PCM solution, achieving high loading rate and leak-proof encapsulation. Then, slowly introduce air to restore atmospheric pressure. To achieve an even higher encapsulation rate, repeat the immersion process twice. Afterward, remove the sample, gently wipe away excess phase change material with filter paper, and cool to room temperature to obtain a composite framework filled with phase change material.

[0092] 10. Weigh PDMS prepolymer (Part A) and curing agent (Part B) into a glass beaker at a mass ratio of 10:1, and stir magnetically for 3 minutes at a speed of approximately 150 rpm. Add SiC nanoparticles, accounting for 4 wt% of the total mass of PDMS. Add an equal mass of n-hexane to dilute the PDMS prepolymer. Then, stir magnetically at 350 rpm for 30 minutes, and then transfer to an ultrasonic cleaner (power set to 300W) for 20 minutes of ultrasonic treatment to obtain a uniform, translucent, milky white suspension.

[0093] 11. Using spin coating, uniformly coat the mixed solution obtained in step 10 onto the sample surface obtained in step 9. The spin coating process consists of two stages: the first stage involves spin coating at 1300 rpm for 22 seconds to achieve solution pre-spreading; the second stage involves spin coating at 2700 rpm for 50 seconds to control the final film thickness to approximately 40 μm. After spin coating, transfer the sample to a conventional oven for further curing. Heat treat at 50℃ for 35 minutes, then raise the temperature to 95℃ for 80 minutes, cool with the oven, and remove the sample to obtain the finished product.

[0094] This embodiment presents a phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel modified Ni mesh, comprising a metal skeleton substrate with a porous mesh structure, a composite system of photothermal filler and phase change material encapsulated inside the metal skeleton substrate, and a hydrophobic polymer layer covering the surface of the metal skeleton substrate.

[0095] The phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel modified Ni mesh in this embodiment has a water contact angle of 127.1±2.5°, a contact angle hysteresis of 6.0°, and a delayed freezing time of 417±8.4s.

[0096] This embodiment describes the application of a phase change photothermal hydrophobic and anti-icing coating based on carbon nanotube SiO2 aerogel-modified Ni mesh on the surface of engineering components, including wind turbine blades, power transmission lines, UAV wings, communication towers, and radar antennas.

[0097] Comparative Example 1 The only difference between this comparative example and Example 1 is that steps 8 and 9 in Example 1 are omitted, that is, the content of filling with phase change material is omitted.

[0098] Comparative Example 2

[0099] The only difference between this comparative example and Example 1 is that steps 10 and 11 in Example 1 are omitted, that is, the hydrophobic polymer layer is omitted.

[0100] Comparative Example 3

[0101] The only difference between this comparative example and Example 1 is that the type of phase change material was changed in step 8, the photothermal triggering mechanism was removed, and only ordinary phase change energy storage materials were used.

[0102] Specifically, step 8 involves accurately weighing and mixing solid n-tetradecane and n-hexadecane at a specific mass ratio (80:20, phase transition temperature approximately 25°C), and placing the mixture in a dry container. The mixture is then heated in a constant-temperature oven at 75°C for 30 minutes until it completely melts into a transparent liquid, forming a homogeneous eutectic phase change material (PCM) solution. Simultaneously, the aerogel / Ni mesh skeleton obtained in step 7 is preheated at 75°C for 15 minutes.

[0103] Characterization and testing methods: Optical microscopy analysis: The surface morphology of the prepared anti-icing coating was characterized using a Nikon Microscope.

[0104] Scanning electron microscopy analysis: The surface microstructure of the prepared anti-icing coating was characterized using a JEOL-6490LV SEM with a scanning voltage of 20 kV and a working distance of 10 mm. Since the coating surface is non-conductive, a platinum spraying treatment was performed before imaging to add a platinum (Pt) layer to the coating, making it conductive.

[0105] Static water contact angle test: The surface wettability of the coating was tested using a fully automated optical contact angle measuring instrument (FTA200, First Ten Angstroms) from the United States. The test solvent was deionized water, the volume of the test droplet was 5µL, the release rate was 1µL / s, and 5 locations were selected for testing for each sample, and the average value was calculated.

[0106] Surface 3D morphology analysis: The surface roughness and 3D morphology characteristics of the prepared samples were analyzed using a three-dimensional profilometer (UP-3000) non-contact optical profilometer.

[0107] Supercooled droplet freezing delay effect test: The freezing delay effect of supercooled droplets on different samples was evaluated using a freezing stage (temperature set to -20 ℃), and the specific freezing process of supercooled droplets on the sample surface was recorded to determine its duration. For each sample, a 5 µL water droplet was used for testing, and five different test points were selected. To ensure consistency of starting conditions, all samples were stored at room temperature.

[0108] Coating thermal regulation capability test: The prepared coating sample was placed on a constant temperature plate (48°C) and the temperature change during the heating process was recorded. Then it was placed on a constant temperature plate (14°C) and the temperature change during the cooling process was recorded. The temperature regulation characteristics were tested by recording the temperature changes during the heating and cooling processes.

[0109] It should be understood that, in order to simplify this disclosure and aid in understanding one or more of the various aspects of the invention, features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof in the above description of exemplary embodiments of the invention. However, this method of disclosure should not be interpreted as reflecting an intention that the claimed invention requires more features than expressly recited in each claim. Rather, as reflected in the claims, inventive aspects lie in fewer than all the features of the foregoingly disclosed embodiments. Therefore, the claims, following the detailed description, are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the invention.

[0110] Although the invention has been described with reference to a limited number of embodiments, those skilled in the art will understand from the foregoing description that other embodiments are conceivable within the scope of the invention described herein. Furthermore, it should be noted that the language used in this specification has been chosen primarily for readability and instructional purposes, and not for the purpose of interpreting or limiting the subject matter of the invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the invention is illustrative and not restrictive, and the scope of the invention is defined by the appended claims.

[0111] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel-modified Ni mesh, characterized in that, It includes a metal skeleton substrate with a porous mesh structure, a composite system of photothermal filler and phase change material encapsulated inside the metal skeleton substrate, and a hydrophobic polymer layer covering the surface of the metal skeleton substrate.

2. The phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel modified Ni mesh according to claim 1, characterized in that, The metal framework substrate includes a porous nickel mesh substrate with a surface pore size of 200-300 μm and a thickness of 0.5-1.5 mm.

3. The phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel modified Ni mesh according to claim 1, characterized in that, Photothermal fillers include carbon nanotube / SiO2 composite materials; phase change materials include fatty acid phase change materials, which include a binary eutectic mixture of lauric acid and myristic acid with a phase change temperature between 20-35℃.

4. The phase change photothermal hydrophobic anti-icing coating based on carbon nanotube SiO2 aerogel modified Ni mesh according to claim 1, characterized in that, The hydrophobic polymer layer is made of polydimethylsiloxane (PDMS) and SiC particles equivalent to 1-5 wt% of PDMS.

5. A method for preparing a phase change photothermal hydrophobic anti-icing coating based on a carbon nanotube SiO2 aerogel-modified Ni mesh according to any one of claims 1 to 4, characterized in that, Includes the following steps: Step 1: Pretreatment of the metal skeleton substrate: Clean the porous nickel mesh substrate and then dry it; Step 2: Prepare carboxylated multi-walled carbon nanotubes (MWCNTs). Disperse a certain amount of carboxylated MWCNTs in anhydrous ethanol at a concentration of 0.5-1.5 mg / mL, and sonicate them at a power of 300-500W for 30-60 minutes to form a uniform carbon nanotube dispersion. Step 3: Under continuous magnetic stirring at 280-320 rpm, tetraethyl orthosilicate is added dropwise to the carbon nanotube dispersion obtained in Step 2, and stirring is continued for 25-35 minutes. The molar ratio of tetraethyl orthosilicate to anhydrous ethanol is controlled at 1:4 to 1:

8. Step 4: Catalysis and hydrolysis process: Under continuous stirring at 280-320 rpm, add dropwise a mixed solution of deionized water and ethanol containing the catalyst, wherein the molar ratio of tetraethyl orthosilicate:ethanol:deionized water:catalyst is controlled at 1:6:3:0.05; the catalyst is hydrochloric acid or ammonia water, and its concentration is 0.05-0.2 M; After the addition is complete, seal the mouth of the beaker with sealing film and continuously stir magnetically at 180-220 rpm for 3.5-4.5 hours at room temperature to form carbon nanotube / SiO2 sol; Step 5: Immerse the pretreated porous nickel mesh substrate from Step 1 into the carbon nanotube / SiO2 sol prepared in Step 4, ensuring that the porous nickel mesh substrate is completely wetted so that the carbon nanotube / SiO2 sol fully fills the macroscopic pores of the porous nickel mesh substrate; use a dip coating machine to vertically and smoothly pull the porous nickel mesh substrate out of the liquid surface of the carbon nanotube / SiO2 sol at a speed of 1-3 mm / s; Step 6: Place the porous nickel mesh substrate with carbon nanotubes / SiO2 sol on a polytetrafluoroethylene plate and transfer the whole thing to a sealed container; let it stand at 30-45℃ for 20-28 hours to complete the hydrolysis-condensation reaction and form a wet gel. At this point, the pores of the porous nickel mesh substrate have been filled with carbon nanotube / SiO2 composite wet gel; Step 7: Subsequently, solvent replacement is performed. The sample aged in Step 6 is immersed in anhydrous ethanol for 10-14 hours to shrink and strengthen the gel network. The sample is then removed from the ethanol and immersed in n-hexane for 10-14 hours, with fresh n-hexane replaced every 4 hours. The sample after n-hexane replacement is then placed in a fume hood and allowed to air dry at room temperature for 1-3 hours. The sample is then transferred to a forced-air drying oven at 40-60℃ and dried for 3-5 hours to obtain an aerogel / porous nickel mesh substrate. Step 8: Heat the fatty acid phase change material, a binary eutectic mixture of lauric acid and myristic acid with a phase change temperature between 20-35℃, to 60-80℃ to obtain a molten PCM liquid; at the same time, preheat the aerogel / porous nickel mesh substrate obtained in Step 7 at 70-80℃ for 12-18 minutes. Step 9: Quickly immerse the preheated aerogel / porous nickel mesh substrate in molten PCM, and transfer the entire beaker to a vacuum drying oven. Maintain this position for 30-120 minutes, utilizing the synergistic effect of a vacuum negative pressure of 0.08-0.1 MPa and capillary action to force the molten PCM into and fill the nanopores of the aerogel. Then, slowly introduce air to restore atmospheric pressure. Repeat the cyclic immersion process 2-3 times. Afterward, remove the sample, wipe off any excess fatty acid phase change material from the surface, and cool to room temperature to obtain a composite framework filled with phase change material. Step 10: Mix Part A and Part B of polydimethylsiloxane PDMS at a mass ratio of 10:1, and add SiC particles equivalent to 1-5 wt% of polydimethylsiloxane PDMS as reinforcing filler. Dissolve the mixture in n-hexane of equal mass to polydimethylsiloxane PDMS, stir magnetically and sonicate to ensure uniform dispersion; obtain a uniform, translucent milky white suspension. Step 11: Use spin coating to evenly coat the suspension obtained in Step 10 onto the sample surface obtained in Step 9; after the spin coating operation is completed, transfer the sample to an oven for a second time, cool it in the oven, and take out the sample to obtain the finished product.

6. The preparation method according to claim 5, characterized in that, In step two, the carboxylated multi-walled carbon nanotubes (MWCNTs) have a length of 10-30 μm, a purity > 95 wt%, and an outer diameter of 10-20 nm. Before ultrasonic treatment, pre-dispersion is first performed by using a magnetic stirrer to stir for at least 30 minutes at a speed of 400-500 rpm to initially wet the carboxylated multi-walled carbon nanotubes (MWCNTs). Ultrasonic treatment involves using an ultrasonic cell disruptor and utilizing the cavitation effect to break up the bundles of carboxylated multi-walled carbon nanotubes (MWCNTs) to form a uniform and stable black dispersion, ideally with no visible precipitate after standing for 24 hours.

7. The preparation method according to claim 5, characterized in that, In step eleven, the spin coating process is divided into two stages: the first stage is to spin coat at a speed of 1000-1500 rpm for 15-25 seconds to achieve solution pre-spreading, and the second stage is to spin coat at a speed of 2000-3000 rpm for 40-60 seconds to control the final film thickness at 20-50 μm.

8. The preparation method according to claim 5, characterized in that, In step eleven, the curing process is as follows: heat treatment at 40-60℃ for 30-60 minutes, followed by heating at 80-100℃ for 1-2 hours.

9. The application of a phase change photothermal hydrophobic and anti-icing coating based on carbon nanotube SiO2 aerogel modified Ni mesh according to any one of claims 1 to 4 on the surface of engineering components, characterized in that, Engineering components include wind turbine blades, drone wings, power transmission lines, communication towers, or radar antennas.

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