Temperature response type hydrophilic and hydrophobic patterned photo-thermal surface as well as construction method and application thereof

Abstract

The invention discloses a temperature response type hydrophilic and hydrophobic patterned photo-thermal surface as well as a construction method and application thereof, and relates to the technical field of industrial defrosting. According to the method, accurate frost control is adopted, the problem of photo-thermal defrosting failure is solved, the characteristic that a temperature response material spontaneously forms a hydrophilic-hydrophobic patterned surface at low temperature is utilized, accurate regulation and control of local frost accumulation and local dryness keeping are achieved through wettability difference, photo-thermal conversion efficiency attenuation or failure caused by frost layer full-surface covering is avoided, and the method is suitable for large-scale popularization and application. The defrosting function is stable and continuous; the characteristics that an ice layer in the hydrophilic area is excellent in light transmittance and a frost layer in the super-hydrophobic area is loose and easy to melt are utilized, the maximum utilization of the photo-thermal conversion efficiency and the maximum photo-thermal conversion efficiency are achieved, heat is accurately conducted to the frost layer area through the positive feedback cycle design, the problems that defrosting power is insufficient and melting is slow in the low-temperature environment are solved, and the defrosting efficiency is improved. The defrosting rate and the photo-thermal utilization efficiency are remarkably improved, and the technical problem of rapid defrosting in the low-temperature environment is solved.

Description

Technical Field

[0001] This invention relates to the field of industrial defrosting technology, specifically to temperature-responsive hydrophilic and hydrophobic patterned photothermal surfaces, their construction methods, and applications. Background Technology

[0002] In low-temperature and high-humidity environments, frost accumulation and frost buildup are prone to occur on the surfaces of industrial facilities (such as heat exchangers, power transmission lines, wind turbines, and air conditioning systems). This significantly reduces the heat transfer efficiency of equipment, resulting in substantial energy consumption and socio-economic losses. Currently, mainstream defrosting technologies in the industrial field can be divided into two main categories: active and passive. Active defrosting requires additional energy input to remove frost, while passive defrosting, through surface functional design, delays frost formation or enables autonomous removal without additional energy consumption, and has become a key research focus in current defrosting technology. Passive defrosting technology primarily focuses on the following two core directions:

[0003] (1) Surface wettability regulation anti-frost technology: The frosting process is intervened by constructing special wettable surfaces. For example, superhydrophobic surfaces can delay the formation of ice nuclei by taking advantage of the low solid-liquid contact area, while promoting the merging and bouncing of surface droplets, thus achieving active removal of water before frosting; while superhydrophilic surfaces can induce the formation of a dense ice layer in the early stage of frosting, and control the thickness of the frost layer by inhibiting the loose growth of the frost layer, thereby reducing the difficulty of defrosting.

[0004] (2) Photothermal conversion defrosting technology: Photothermal conversion materials, represented by carbon-based materials, have the ability to efficiently absorb sunlight and convert light energy into heat energy. They can heat up the surface through the photothermal effect and melt the frost on the surface. This technology directly utilizes solar energy, a clean energy source, and has both economic and environmental advantages. Moreover, the application process does not require manual intervention, does not require damage to the original structure of the equipment, and does not require direct contact with the defrosting surface. It has extremely high application potential in industrial scenarios and has attracted much attention from the industry.

[0005] Although the aforementioned passive defrosting technology has a certain defrosting effect, it still faces insurmountable technical bottlenecks under actual low-temperature and high-humidity conditions. The specific drawbacks are as follows:

[0006] (1) Limitations of wettability-controlled defrosting technology: No matter whether the surface is superhydrophobic or superhydrophilic, it is impossible to completely avoid frost formation. As time goes on, the frost layer will gradually form and spread on the surface, eventually achieving full surface coverage; and in low-temperature environments, the frost layer melts slowly, making it impossible to achieve rapid defrosting. At the same time, melted droplets are easy to remain on the surface, which can easily cause secondary frost formation, resulting in a continuous decline in the defrosting effect.

[0007] (2) The core pain point of photothermal conversion defrosting technology: the photothermal surface will still frost normally during periods without light, and the frost layer formed has a high light reflectivity, which will seriously hinder the absorption of sunlight by the photothermal conversion material; when the frost layer covers the entire surface, the photothermal conversion efficiency will decrease sharply or even be completely lost, resulting in the failure of the defrosting function under light conditions, and the inability to achieve a stable and continuous defrosting effect.

[0008] In summary, the key bottleneck for the industrial application of photothermal de-icing technology lies in reconciling the core contradiction between "inevitable surface frost formation" and "efficient photothermal defrosting" and solving the problem of functional failure of photothermal conversion materials due to frost coverage.

[0009] Therefore, a new solution is needed to address the above problems. Summary of the Invention

[0010] The purpose of this invention is to provide a temperature-responsive hydrophilic and hydrophobic patterned photothermal surface, its construction method, and its application, thereby solving the problem of photothermal defrosting failure at its root, improving defrosting efficiency and continuity, and addressing the technical problems mentioned in the background art.

[0011] To achieve the above objectives, the present invention provides the following technical solution: a method for constructing temperature-responsive hydrophilic-hydrophobic patterned photothermal surfaces, comprising at least the following steps:

[0012] S1: Substrate pretreatment: Cleaning (removing oil and oxide layers) the surface of substrates for various industrial facilities without requiring additional structural processing of the substrate;

[0013] S2: A temperature-responsive wettability-transition photothermal conversion material is made into a coating slurry and uniformly coated onto the surface of a substrate to form a functional layer.

[0014] S3: Curing and molding, after low-temperature curing or natural drying, the functional layer and the substrate form a stable physical adsorption and interfacial bond.

[0015] S4: Patterning is formed autonomously. The functional layer spontaneously forms a patterned structure of hydrophilic and hydrophobic regions under low-temperature conditions, without relying on the pre-pattern design of the substrate.

[0016] Furthermore, the temperature-responsive wettability transition photothermal conversion material includes at least polyvinylcaprolactam, wherein the alkenylcaprolactam is PNVCL, and the lower critical dissolution temperature of the polyvinylcaprolactam is 31.5℃-35℃.

[0017] Furthermore, the low-temperature operating condition is a low-temperature and high-humidity environment that easily causes frost formation on the surface of industrial facilities. When the temperature is lower than the low critical dissolution temperature of the functional layer under the low-temperature operating condition, the functional layer forms a patterned structure of hydrophilic-hydrophobic regions by transforming the properties of the photothermal conversion material through temperature-responsive wettability.

[0018] Furthermore, the various industrial facilities include at least heat exchangers, power transmission lines, wind turbines, or air conditioning systems.

[0019] A temperature-responsive hydrophilic-hydrophobic patterned photothermal surface was constructed using a temperature-responsive hydrophilic-hydrophobic patterned photothermal surface construction method.

[0020] Application of temperature-responsive hydrophilic and hydrophobic patterned photothermal surfaces: These surfaces are used for defrosting, defrosting, and drainage on industrial facility surfaces in low-temperature and high-humidity environments.

[0021] Furthermore, the defrosting, defrosting, and drainage methods applied to the surface of industrial facilities include at least the following steps:

[0022] S1: Defrosting: The functional layer of the photothermal surface spontaneously forms a patterned structure of hydrophilic and hydrophobic water zones under low-temperature conditions. It achieves precise defrosting control by controlling local frost accumulation and local dryness through wettability differences, thus preserving the photothermal conversion channel.

[0023] S2: Defrost: Under light conditions, the frost-free dry area of ​​the patterned surface absorbs sunlight and undergoes photothermal conversion to generate heat. The heat is conducted laterally to the frost-covered area, forming defrost, which drives the frost and ice to melt.

[0024] S3: Drainage: The surface temperature rise caused by photothermal conversion triggers the functional layer to change from hydrophilic to hydrophobic properties. Combined with natural external forces and the hydrophilic-hydrophobic wettability gradient, it enables the rapid self-desorption and directional migration of defrost droplets, thus completing efficient drainage to prevent secondary frosting.

[0025] S4: The heat generated by photothermal conversion forms a positive feedback loop.

[0026] Furthermore, in the patterned structure of the hydrophilic-hydrophobic regions, the hydrophilic regions form a continuous ice layer, and the superhydrophobic regions form a discrete loose frost layer. The light transmittance of the continuous ice layer is better than that of the discrete loose frost layer.

[0027] Furthermore, the natural external forces mentioned include at least gravity and wind.

[0028] Furthermore, S5 includes at least the following steps:

[0029] Initial stage: There are some dry areas on the patterned surface of the hydrophilic-hydrophobic zone. Under light, photothermal conversion generates heat and melts the surrounding frost layer.

[0030] Phase 1: After the frost melts, the area that was originally covered becomes a dry area again, and the area for absorbing light and heat increases.

[0031] Phase Two: More dry areas absorb sunlight, generating significantly more heat.

[0032] Third stage: Additional heat is conducted laterally to quickly melt the remaining frost layer, further expanding the dry area;

[0033] Cyclic upgrade phase: The newly restored dry zone continues to enhance photothermal conversion until the frost layer in the entire area completely melts, at which point the cycle ends.

[0034] Compared with the prior art, the beneficial effects of the present invention are:

[0035] 1. This invention employs precise defrosting control to solve the problem of photothermal defrosting failure. It utilizes the characteristic of temperature-responsive materials to spontaneously form hydrophilic-hydrophobic patterned surfaces at low temperatures. By controlling the difference in wettability, it achieves precise control over localized frost accumulation and localized dryness, avoiding the attenuation or failure of photothermal conversion efficiency caused by full surface coverage of frost, and ensuring stable and continuous defrosting function.

[0036] 2. This invention utilizes the excellent light transmittance of the hydrophilic ice layer and the loose and easily meltable frost layer of the superhydrophobic region to maximize the utilization of photothermal conversion efficiency. By maximizing the photothermal conversion efficiency and through positive feedback loop design, heat is accurately conducted to the frost layer area, solving the problems of insufficient defrosting power and slow melting in low-temperature environments. This significantly improves the defrosting rate and photothermal utilization efficiency, and solves the technical problem of rapid defrosting in low-temperature environments.

[0037] 3. This invention features efficient liquid drainage, thereby avoiding secondary frosting. Through the design of photothermal conversion to change the hydrophilic-hydrophobic properties of the material, and relying on the low adhesion effect of the hydrophobic surface, the defrosting droplets can quickly self-desorb under the action of natural external force, achieving efficient liquid drainage. This design not only solves the problem of defrosting droplet residue in the prior art, but also fundamentally eliminates secondary frosting caused by residual droplets, ensuring the long-lasting effect of defrosting and avoiding repeated decay of the defrosting function.

[0038] 4. This invention operates entirely passively, offering excellent economy and adaptability. It requires no additional energy input and relies on temperature response, solar energy, and natural external forces to achieve fully passive defrosting, reducing energy consumption and maintenance costs. It is suitable for low-temperature and high-humidity operating conditions in various industrial facilities.

[0039] 5. This invention simplifies the application process and reduces the difficulty of engineering implementation. The temperature-responsive wettability transition photothermal conversion material can spontaneously form a hydrophilic-hydrophobic patterned surface without the need for complex artificial pattern preparation and control processes. At the same time, the solution does not require destructive modification of the substrate and structure of existing industrial facilities and can be directly adapted to the surface modification needs of existing equipment, reducing the difficulty and cost of engineering implementation and facilitating the large-scale promotion of the technology. Attached Figure Description

[0040] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of the photothermal-wetting synergistic defrosting method of the present invention;

[0042] Figure 2 This is a schematic diagram of melt water migration during the patterned surface defrosting process of the present invention;

[0043] Figure 3 This is an observation diagram of meltwater traction migration during defrosting on the hydrophilic and hydrophobic patterned surface of the present invention. Detailed Implementation

[0044] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0045] This invention achieves multi-dimensional technological breakthroughs and produces significant technical effects compared to existing wettability-controlled defrosting technology and photothermal conversion defrosting technology through innovative designs of temperature-responsive wettability-transition photothermal conversion photothermal conversion material, hydrophilic-hydrophobic patterned surface, and photothermal-wetting conversion synergistic mechanism.

[0046] Specifically as follows:

[0047] Example 1:

[0048] A method for constructing temperature-responsive hydrophobic patterned photothermal surfaces includes at least the following steps:

[0049] S1: Substrate pretreatment: Cleaning (removing oil and oxide layers) the surface of substrates for various industrial facilities without requiring additional structural processing of the substrate;

[0050] S2: A temperature-responsive wettability-transition photothermal conversion material is made into a coating slurry and uniformly coated onto the surface of a substrate to form a functional layer.

[0051] S3: Curing and molding, after low-temperature curing or natural drying, the functional layer and the substrate form a stable physical adsorption and interfacial bond.

[0052] S4: Patterning is formed autonomously. The functional layer spontaneously forms a patterned structure of hydrophilic and hydrophobic regions under low-temperature conditions, without relying on the pre-pattern design of the substrate.

[0053] Temperature-responsive wettability transition photothermal conversion materials include at least polyvinylcaprolactam, alkenylcaprolactam (PNVCL), and the low critical dissolution temperature of polyvinylcaprolactam is 31.5℃-35℃.

[0054] Low-temperature operating conditions are low-temperature and high-humidity environments that easily cause frost formation on the surface of industrial facilities. When the temperature is lower than the low critical dissolution temperature of the functional layer under low-temperature operating conditions, the functional layer forms a patterned structure of hydrophilic-hydrophobic regions by transforming the properties of the photothermal conversion material through temperature-responsive wettability.

[0055] Various industrial facilities include at least heat exchangers, power transmission lines, wind turbines, or air conditioning systems.

[0056] Example 2:

[0057] A temperature-responsive hydrophilic-hydrophobic patterned photothermal surface was constructed using the method disclosed in Example 1.

[0058] Example 3:

[0059] To address the three core challenges in existing technologies—"unavoidable surface frost formation," "failure of photothermal defrosting due to full frost coverage," and "the inability of defrosting droplets to detach in time, easily leading to secondary frost formation"—this invention proposes a fully passive solution for synergistic frost control, defrosting, and liquid drainage on a patterned surface featuring "photothermal conversion-wetting transformation."

[0060] See Figures 1 to 3 This paper proposes the application of temperature-responsive hydrophilic and hydrophobic patterned photothermal surfaces, and uses these surfaces for defrosting, defrost control, and liquid drainage on industrial facility surfaces in low-temperature and high-humidity environments.

[0061] This embodiment achieves efficient defrosting through the synergistic effect of three core mechanisms:

[0062] Using polyvinyl caprolactone as the core temperature-responsive wettability transition photothermal conversion material, and relying on its low critical dissolution temperature of 31.5-35℃, a composite surface constructed through surface patterning modification can spontaneously form patterned surfaces with hydrophilic and hydrophobic regions under low-temperature conditions. By utilizing the difference in surface wettability, a precise frost control effect of "local frost accumulation and local dryness" is achieved, fundamentally preventing the surface from being completely covered by a frost layer with high light reflectivity, and ensuring the effective preservation of the photothermal conversion channel.

[0063] See Figure 1 Under illumination, sunlight can directly act on the frost-free and dry areas of the surface. After absorbing sunlight, the photothermal conversion material generates heat through photothermal conversion. The heat is then conducted laterally along the surface to the frost-covered area, thereby driving the frost to melt efficiently.

[0064] The surface temperature rise caused by photothermal conversion can further trigger the material to change from hydrophilic to hydrophobic properties. Relying on the low adhesion effect of the hydrophobic surface, the defrosting droplets can quickly self-desorb under the action of external force, achieving efficient drainage and preventing secondary frosting.

[0065] See Figure 2 In low-temperature environments, temperature-responsive photothermal conversion materials undergo a self-transformation of wettability, forming a patterned structure of hydrophilic and hydrophobic properties on their surface. The hydrophilic regions readily condense to form a continuous ice layer, while the superhydrophobic regions tend to generate a discrete, loose frost layer. Compared to the loose frost layer with high light reflectivity, the continuous ice layer exhibits superior light transmittance. When sunlight shines, the light can penetrate the ice layer in the hydrophilic regions to reach the photothermal conversion substrate. The substrate absorbs the light energy and converts it into heat energy, raising the surface temperature. This temperature rise preferentially melts the loosely structured frost layer in the superhydrophobic regions. Driven by the hydrophilic-hydrophobic wettability gradient, the melted droplets actively and rapidly migrate directionally to the hydrophilic regions, allowing the superhydrophobic regions to recover their clean and dry state first. Subsequently, the dry superhydrophobic region can absorb sunlight efficiently and without obstruction and enhance photothermal conversion. The heat generated acts directly on the residual frost layer on the one hand, and is transferred to the adjacent hydrophilic region through heat conduction on the other hand, which accelerates the melting process of the ice layer and residual frost layer in that area, forming a positive feedback loop of "photothermal conversion - defrosting and desorption - heat transfer - full-area defrosting", which greatly improves the photothermal utilization efficiency and defrosting rate.

[0066] In addition, the temperature rise caused by photothermal conversion will also trigger the hydrophilic material to change from hydrophilic to hydrophobic. With the help of the low adhesion effect of the hydrophobic surface, the rapid desorption of ice in the hydrophilic region is accelerated, and secondary frosting caused by meltwater residue is completely eliminated.

[0067] Therefore, this invention achieves synergistic enhancement of "wetting transformation for defrosting, photothermal conversion for defrosting, and thermo-induced hydrophobic drainage" under fully passive conditions. It not only breaks through the technical bottleneck of insufficient defrosting power and slow surface drying of traditional wettable patterned surfaces in low-temperature environments, but also completely solves the core problem of defrosting failure caused by frost layer coverage of photothermal conversion materials. It has significant advantages of being stable, efficient, and requiring no additional energy consumption.

[0068] Figure 3 This indicates the migration of meltwater from the hydrophobic region during defrosting. Experimental observations show that the hydrophobic surface area indicated by the red circle has already frosted under low-temperature conditions. Due to the directional pull of the hydrophilic region, meltwater on the hydrophobic surface migrates efficiently towards the hydrophilic region. Ultimately, no meltwater retention was observed on the hydrophobic surface, which directly demonstrates the efficient guiding effect of the difference in wetting behavior between the hydrophilic and hydrophobic interfaces on meltwater, effectively achieving rapid transfer of meltwater from the hydrophobic surface and thus enhancing the liquid film removal effect during defrosting.

[0069] In summary:

[0070] 1. This invention establishes a fully passive synergistic control system: integrating three core mechanisms—temperature-responsive wettability change for defrosting, photothermal conversion-lateral thermal conduction for defrosting, and thermally induced hydrophobic drainage—to construct a fully passive synergistic control system that requires no additional energy consumption, thereby achieving synergistic enhancement of the three mechanisms and ensuring stable and efficient operation of the solution.

[0071] 2. This invention uses a temperature-responsive wettability transition photothermal conversion material as the functional layer. This material is the core carrier for achieving the synergistic effects of defrosting, defrosting, and liquid drainage. It simultaneously possesses temperature-responsive wettability transition characteristics and efficient photothermal conversion characteristics, providing a fundamental guarantee for a fully passive solution.

[0072] 3. This invention employs a hydrophilic-hydrophobic partitioned patterned surface construction technology. Through the autonomous wettability transformation of temperature-responsive materials, a patterned surface structure with hydrophilic-hydrophobic partitions is spontaneously formed under low-temperature conditions. By leveraging the wettability differences, precise frost control is achieved for localized frost accumulation and localized dryness retention, thus preserving the photothermal conversion channel from the source and solving the problem of traditional photothermal materials failing due to full frost coverage.

[0073] 4. This invention adopts a photothermal conversion-lateral heat conduction synergistic defrosting mechanism design. It utilizes the frost-free dry area of ​​the patterned surface to efficiently absorb sunlight and generate heat through photothermal conversion. At the same time, it constructs a lateral heat conduction path to directionally transfer heat to the frost-covered area, driving the frost and ice layers to melt efficiently, thus overcoming the bottleneck of insufficient low-temperature defrosting power of traditional wettable patterned surfaces.

[0074] 5. This invention employs a thermo-induced wettability secondary transformation-driven drainage technology. By leveraging the surface temperature rise caused by photothermal conversion, the material (including hydrophilic regions) is triggered to transform from hydrophilic to hydrophobic. Utilizing the low adhesion effect of the hydrophobic surface, combined with natural external forces such as gravity and wind, rapid self-desorption of defrosting / ice-melting droplets is achieved. Simultaneously, the melt is driven to migrate in a directional manner through the hydrophilic-hydrophobic wettability gradient, ensuring efficient drainage across the entire area and preventing secondary frosting.

[0075] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for constructing temperature-responsive hydrophilic-hydrophobic patterned photothermal surfaces, characterized in that: At least the following steps are included: S1: Substrate pretreatment: Cleaning the surface of the substrate for industrial facilities without requiring additional structural processing of the substrate; S2: A temperature-responsive wettability-transition photothermal conversion material is made into a coating slurry and uniformly coated onto the surface of a substrate to form a functional layer. S3: Curing and molding, after low-temperature curing or natural drying, the functional layer and the substrate form a stable physical adsorption and interfacial bond. S4: Patterning is formed autonomously. The functional layer spontaneously forms a patterned structure of hydrophilic and hydrophobic regions under low-temperature conditions, without relying on the pre-pattern design of the substrate.

2. The method for constructing a temperature-responsive hydrophobic patterned photothermal surface according to claim 1, characterized in that: The temperature-responsive wettability transition photothermal conversion material includes at least polyvinyl caprolactam, wherein the lower critical dissolution temperature of the polyvinyl caprolactam is 31.5℃-35℃.

3. The method for constructing a temperature-responsive hydrophilic-hydrophobic patterned photothermal surface according to claim 2, characterized in that: The low-temperature operating condition is a low-temperature and high-humidity environment that easily causes frost formation on the surface of industrial facilities. When the temperature is lower than the low critical dissolution temperature of the functional layer under the low-temperature operating condition, the functional layer forms a patterned structure of hydrophilic-hydrophobic regions by transforming the properties of the photothermal conversion material through temperature-responsive wettability.

4. The method for constructing a temperature-responsive hydrophilic-hydrophobic patterned photothermal surface according to claim 1, characterized in that: The industrial facilities include at least heat exchangers, power transmission lines, wind turbines, or air conditioning systems.

5. A temperature-responsive hydrophilic-hydrophobic patterned photothermal surface, characterized in that: It is constructed by the method described in any one of claims 1-4 above.

6. Application of temperature-responsive hydrophilic-hydrophobic patterned photothermal surfaces, characterized by: The temperature-responsive hydrophilic and hydrophobic patterned photothermal surface described in claim 5 is applied to the surface of industrial facilities in low-temperature and high-humidity environments for defrosting, defrosting, and drainage.

7. The application of the temperature-responsive hydrophobic patterned photothermal surface according to claim 6, characterized in that: The defrosting, de-frost, and drainage methods applied to the surfaces of industrial facilities include at least the following steps: S1: Defrosting: The functional layer of the photothermal surface spontaneously forms a patterned structure of hydrophilic and hydrophobic water zones under low-temperature conditions. It achieves precise defrosting control by controlling local frost accumulation and local dryness through wettability differences, thus preserving the photothermal conversion channel. S2: Defrost: Under light conditions, the frost-free dry area of ​​the patterned surface absorbs sunlight and undergoes photothermal conversion to generate heat. The heat is conducted laterally to the frost-covered area, forming defrost, which drives the frost and ice to melt. S3: Drainage: The surface temperature rise caused by photothermal conversion triggers the functional layer to change from hydrophilic to hydrophobic properties. Combined with natural external forces and the hydrophilic-hydrophobic wettability gradient, it enables the rapid self-desorption and directional migration of defrost droplets, thus completing efficient drainage to prevent secondary frosting. S4: The heat generated by photothermal conversion forms a positive feedback loop.

8. The application of the temperature-responsive hydrophilic-phobic patterned photothermal surface according to claim 7, characterized in that: In the patterned structure of the hydrophilic-hydrophobic regions, the hydrophilic regions form a continuous ice layer, and the superhydrophobic regions form a discrete loose frost layer. The light transmittance of the continuous ice layer is better than that of the discrete loose frost layer.

9. The application of the temperature-responsive hydrophobic patterned photothermal surface according to claim 8, characterized in that: The natural external forces mentioned include at least gravity and wind.

10. The application of the temperature-responsive hydrophobic patterned photothermal surface according to claim 9, characterized in that: The S4 includes at least the following steps: Initial stage: There are some dry areas on the patterned surface of the hydrophilic-hydrophobic zone. Under light, photothermal conversion generates heat and melts the surrounding frost layer. Phase 1: After the frost melts, the area that was originally covered becomes a dry area again, and the area for absorbing light and heat increases. Phase Two: More dry areas absorb sunlight, generating significantly more heat. Third stage: Additional heat is conducted laterally to quickly melt the remaining frost layer, further expanding the dry area; Cyclic upgrade phase: The newly restored dry zone continues to enhance photothermal conversion until the frost layer in the entire area completely melts, at which point the cycle ends.

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