A corrosion-resistant, self-cleaning, light-reflecting ceramic coating and its preparation method

Abstract

This invention discloses a corrosion-resistant, self-cleaning, light-reflecting ceramic coating and its preparation method, belonging to the field of surface treatment technology. The coating solution is applied to a substrate material using a scraping method to form the corrosion-resistant, self-cleaning, light-reflecting ceramic coating. The coating solution includes silica sol, silane coupling agent, wetting agent, tetrafluoroethylene particles, formic acid, and titanium dioxide nanoparticles, with the titanium dioxide nanoparticles comprising 12 wt.%–30 wt.%. This light-reflecting ceramic coating is a high-performance coating that can be used as a cooling coating for buildings. It effectively improves the light reflectivity of the substrate, thereby significantly reducing surface temperature and heat radiation absorption. It is particularly suitable for thermal management of building exterior walls and windows, achieving excellent energy-saving and cooling effects.

Description

Technical Field

[0001] This invention belongs to the field of surface treatment technology, specifically a corrosion-resistant, self-cleaning, light-reflecting ceramic coating and its preparation method. Background Technology

[0002] With the increasing severity of global climate change and energy shortages, building energy conservation has become a focus of social attention. Traditional building cooling methods mainly rely on mechanical equipment such as air conditioners, which not only consume a large amount of energy but also emit large amounts of greenhouse gases, further exacerbating climate change. Therefore, developing new energy-saving materials to reduce building energy consumption is particularly important.

[0003] Light-reflective cooling technology is a green, passive cooling solution that reduces heat accumulation and lowers indoor temperatures by efficiently reflecting solar radiation through a coating surface. Most existing reflective coatings use polymer materials, but these materials are easily degraded by ultraviolet radiation, leading to decreased reflectivity and durability, making them unsuitable for long-term use. In contrast, ceramic-based coatings have gained widespread attention due to their excellent weather resistance and chemical stability. Among them, titanium dioxide (TiO2), as a highly efficient light-reflective material, not only possesses excellent reflectivity but also withstands high temperatures and ultraviolet radiation, demonstrating great potential in building energy conservation. However, existing TiO2 coatings still suffer from insufficient adhesion, easy peeling, and limited corrosion resistance in practical applications, hindering their widespread adoption. Summary of the Invention

[0004] To address the problems of TiO2 coatings in the prior art, this invention provides a corrosion-resistant, self-cleaning, light-reflecting ceramic coating and its preparation method.

[0005] Technical solution: A method for preparing a corrosion-resistant, self-cleaning, light-reflecting ceramic coating, wherein a coating solution is applied to a substrate material by a scraping method to form a corrosion-resistant, self-cleaning, light-reflecting ceramic coating; the coating solution includes silica sol, silane coupling agent, wetting agent, tetrafluoroethylene particles, formic acid, and titanium dioxide nanoparticles.

[0006] Preferably, the content of titanium dioxide nanoparticles in the coating solution is 12 wt.%-30 wt.%.

[0007] Preferably, the content of each component in the coating solution is as follows:

[0008] Silane coupling agent, 24.5 wt.%–42.5 wt.%;

[0009] Silica sol, 40 wt.%;

[0010] Wetting agent, 0.1–0.3%;

[0011] Polytetrafluoroethylene granules, 5 wt.%;

[0012] Formic acid, 0.3 wt.%;

[0013] Titanium dioxide nanoparticles, 12 wt.%-30 wt.%.

[0014] Preferably, the silane coupling agent is methyltrimethoxysilane; the wetting agent is wetting agent BYK-310; and the titanium dioxide nanoparticles are rutile titanium dioxide nanomaterials with a particle size of approximately 250 nm.

[0015] A preferred method for preparing a corrosion-resistant, self-cleaning, light-reflecting ceramic coating includes the following steps:

[0016] Step 1: Add silane coupling agent, silica sol, wetting agent, polytetrafluoroethylene particles and formic acid to a reagent bottle, and mix them evenly on a shaker at 3000 rpm to obtain the basic solution.

[0017] Step 2: Add titanium dioxide nanoparticles of different concentrations to the base solution and stir at room temperature for 1 hour to ensure uniform dispersion of the nanoparticles and obtain the coating solution.

[0018] Step 3: Apply the coating solution evenly to the surface of the substrate material, and adjust the coating thickness using a scraping technique;

[0019] Step 4: Bake the coated substrate at 120°C for 30 minutes to complete the coating curing and form a light-reflective ceramic coating.

[0020] Preferably, in step three, the coating thickness is 74 μm, and the coating thickness is achieved by adjusting the gap of the scraper.

[0021] Preferably, the base material is any one of glass, wood, or steel.

[0022] In this invention, methyltrimethoxysilane is used to enhance the adhesion between the coating and the substrate, silica sol is used to improve the hardness and corrosion resistance of the coating, PTFE particles help form a hydrophobic surface and improve the self-cleaning properties of the coating, and wetting agent BYK-310 is used to improve the dispersibility of the coating. The addition of titanium dioxide nanoparticles effectively improves the light reflection performance of the coating. Titanium dioxide itself has good ultraviolet absorption capacity and self-cleaning properties, which can enhance the coating's resistance to contamination. The use of a scraping technique ensures uniform coating thickness, thereby guaranteeing the uniformity and functionality of the coating; baking helps to further improve the stability and corrosion resistance of the coating, allowing the coating to maintain its function for a longer period of time under high temperature and harsh environmental conditions. Adjusting the ratio of methyltrimethoxysilane to silica sol enhances the adhesion and weather resistance of the coating. By adjusting the ratio of titanium dioxide to silica sol, the performance of the light-reflective ceramic coating can be changed. The solar reflectivity of the coating surface prepared by this invention is not less than 80%, and the substrate temperature can be reduced by up to 13°C.

[0023] Beneficial effects:

[0024] 1) The light-reflecting ceramic coating of the present invention is a high-performance light-reflecting ceramic coating that can be used as a cooling coating for buildings. It has excellent solar energy reflectivity, strong adhesion and durability, and can effectively improve the light reflectivity of the substrate, thereby significantly reducing the surface temperature and reducing heat radiation absorption. It is especially suitable for the thermal management of building exterior walls and windows, achieving good energy-saving and cooling effects.

[0025] Compared with traditional polymer-based coatings, the ceramic coating of the present invention has stronger UV stability, corrosion resistance and mechanical properties, which can effectively reduce indoor temperature, reduce the burden on air conditioning and improve the energy efficiency of buildings.

[0026] 2) The ceramic coating prepared by this invention uses ceramic materials, consisting of titanium dioxide (TiO2) nanoparticles, silane coupling agents, and silica sol, and is adhered to a glass substrate. This coating is prepared using an improved low-temperature curing process (120℃), ensuring high adhesion, high reflectivity, and excellent weather resistance. The preparation process is simple and low-cost, and can be prepared at low temperatures, showing broad application prospects, especially suitable for areas with high solar radiation.

[0027] 3) The titanium dioxide nanoparticles in the light-reflecting ceramic coating of the present invention not only improve the light reflection performance, but also have excellent corrosion resistance, which can effectively extend the service life of the coating.

[0028] 4) The ceramic coating prepared by this invention not only possesses high light reflectivity and excellent corrosion resistance, but also exhibits good self-cleaning properties, making it suitable for various surfaces requiring durable protection, particularly in the fields of construction, automobiles, and electronic equipment, where it has broad application prospects. The PTFE particles added to the light-reflecting ceramic coating of this invention endow the coating with excellent self-cleaning characteristics, effectively preventing the adhesion of contaminants, maintaining the long-term stable function of the coating, and reducing maintenance costs. Even in humid or dusty environments, this coating can maintain its efficient reflectivity and self-cleaning function, thereby enhancing the usability of building materials. Attached Figure Description

[0029] Figure 1 Fourier transform infrared spectra of the light-reflecting ceramic coating (0% TiO2) and the light-reflecting ceramic coating (24% TiO2) and the pure TiO2 powder in Examples 1 and 4.

[0030] Figure 2 This is a scanning electron microscope image of the light-reflecting ceramic coating (24% TiO2) in Example 4.

[0031] Figure 3 The images shown are scanning electron microscope (SEM) images, coating cross-section diagrams, and energy dispersive spectroscopy (EDS) diagrams of the light-reflecting ceramic coating (24% TiO2) glass in Example 4.

[0032] Figure 4 This is a macroscopic comparison of light-reflecting ceramic coatings (24% TiO2) under different test conditions.

[0033] Figure 5 This is a schematic diagram showing the results of an indoor simulated house cooling experiment.

[0034] Figure 6 Temperature curves of a simulated house cooling experiment were obtained by irradiating the glass and the glass with a 24% TiO2 light-reflecting ceramic coating for 6 hours under the same ambient light conditions.

[0035] Figure 7 The middle image shows the test results of a three-day outdoor cooling experiment.

[0036] Figure 8 Schematic diagram of a cooling power device for light-reflective ceramic-coated (24% TiO2) glass.

[0037] Figure 9 The image shows the results of the electrochemical corrosion test.

[0038] Figure 10 This is a schematic diagram showing the contact angle of a light-reflecting ceramic coating (24% TiO2).

[0039] Figure 11The image shows a before-and-after comparison of the self-cleaning effect of the light-reflecting ceramic coating (24% TiO2). Detailed Implementation

[0040] The technical solution of the present invention will be described in detail below through embodiments, but the scope of protection of the present invention is not limited to the embodiments described.

[0041] In the following examples, for substances such as silica sol, wetting agent BYK-310, titanium dioxide nanoparticles (R902), and polytetrafluoroethylene (PTFE) particles, where the fixed structure or component parameters are uncertain, please provide the name of the manufacturer or purchaser. Methyltrimethoxysilane (MTMS, 98%), silica sol (alkaline, 30%), and formic acid (98%) were all sourced from Alibaba. Titanium dioxide nanoparticles (R902) were obtained from Chemours, Inc., USA. Polytetrafluoroethylene (PTFE) powder was purchased from Nanjing Tianshi New Materials Technology Co., Ltd. Silicon-based surface additive (BYK-310) was supplied by BYK (Wesel, Germany).

[0042] Example 1: Preparation of a light-reflecting ceramic coating (0% TiO2)

[0043] The preparation method of the light-reflecting ceramic coating (0% TiO2) includes the following steps:

[0044] (1) Add 54.5 wt.% methyltrimethoxysilane, 40 wt.% silica sol, 0.2 wt.% wetting agent BYK-310, 5 wt.% polytetrafluoroethylene (PTFE) particles and 0.3 wt.% formic acid to a 15 mL reagent bottle and mix them evenly on a shaker at 3000 rpm to obtain the basic solution.

[0045] (2) The base solution is uniformly coated onto the surface of the glass substrate, and the coating thickness is adjusted by scraping technique;

[0046] (3) Bake the coated substrate at 120°C for 30 minutes to complete the coating curing and form a ceramic coating (0% TiO2).

[0047] Example 2: Preparation of a light-reflecting ceramic coating (12% TiO2)

[0048] The preparation method of the light-reflecting ceramic coating (12% TiO2) includes the following steps:

[0049] (1) Add 42.5 wt.% methyltrimethoxysilane, 40 wt.% silica sol, 0.2 wt.% wetting agent BYK-310, 5 wt.% polytetrafluoroethylene (PTFE) particles and 0.3 wt.% formic acid to a 15 mL reagent bottle and mix them evenly on a shaker at 3000 rpm to obtain the basic solution.

[0050] (2) Add 12 wt.% of titanium dioxide nanoparticles (R902) to the base solution and stir at room temperature for 1 hour to ensure uniform dispersion of nanoparticles and obtain coating solution;

[0051] (3) Apply the coating solution evenly to the surface of the glass substrate and adjust the coating thickness using a scraping technique;

[0052] (4) Bake the coated substrate at 120°C for 30 minutes to complete the coating curing and form a ceramic coating (12% TiO2).

[0053] Example 3: Preparation of a light-reflecting ceramic coating (18% TiO2)

[0054] The preparation method of the light-reflecting ceramic coating (18% TiO2) includes the following steps:

[0055] (1) Add 36.5 wt.% methyltrimethoxysilane, 40 wt.% silica sol, 0.2 wt.% wetting agent BYK-310, 5 wt.% polytetrafluoroethylene (PTFE) particles and 0.3 wt.% formic acid to a 15 mL reagent bottle and mix them evenly on a shaker at 3000 rpm to obtain the basic solution.

[0056] (2) Add 18 wt.% of titanium dioxide nanoparticles (R902) to the base solution and stir at room temperature for 1 hour to ensure uniform dispersion of the nanoparticles and obtain the coating solution.

[0057] (3) Apply the coating solution evenly to the substrate surface and adjust the coating thickness using a scraping technique;

[0058] (4) Bake the coated substrate at 120°C for 30 minutes to complete the coating curing and form a ceramic coating (18% TiO2).

[0059] Example 4: Preparation of a light-reflecting ceramic coating (24% TiO2)

[0060] The preparation method of the light-reflecting ceramic coating (24% TiO2) includes the following steps:

[0061] (1) Add 30.5 wt.% methyltrimethoxysilane, 40 wt.% silica sol, 0.2 wt.% wetting agent BYK-310, 5 wt.% polytetrafluoroethylene (PTFE) particles and 0.3 wt.% formic acid to a 15 mL reagent bottle and mix them evenly on a shaker at 3000 rpm to obtain the basic solution.

[0062] (2) Add 24 wt.% of titanium dioxide nanoparticles (R902) to the base solution and stir at room temperature for 1 hour to ensure uniform dispersion of the nanoparticles and obtain the coating solution.

[0063] (3) Apply the coating solution evenly to the surface of the glass substrate and adjust the coating thickness using a scraping technique;

[0064] (4) Bake the coated substrate at 120°C for 30 minutes to complete the coating curing and form a ceramic coating (24% TiO2).

[0065] Example 5: Preparation of a light-reflecting ceramic coating (30% TiO2)

[0066] The preparation method of the light-reflecting ceramic coating (30% TiO2) includes the following steps:

[0067] (1) Add 24.5 wt.% methyltrimethoxysilane, 40 wt.% silica sol, 0.2 wt.% wetting agent BYK-310, 5 wt.% polytetrafluoroethylene (PTFE) particles and 0.3 wt.% formic acid to a 15 mL reagent bottle and mix them evenly on a shaker at 3000 rpm to obtain the basic solution.

[0068] (2) Add 30 wt.% of titanium dioxide nanoparticles (R902) to the base solution and stir at room temperature for 1 hour to ensure uniform dispersion of nanoparticles and obtain coating solution;

[0069] (3) Apply the coating solution evenly to the surface of the glass substrate and adjust the coating thickness using a scraping technique;

[0070] (4) Bake the coated substrate at 120°C for 30 minutes to complete the coating curing and form a ceramic coating (30% TiO2).

[0071] The ceramic coatings prepared in Examples 1-5 were characterized and tested, and the results are as follows:

[0072] 1) Figure 1 Fourier transform infrared (FTIR) spectra of ceramic coatings (24% TiO2) are shown, including the ceramic-coated (24% TiO2) glass of Example 4, the ceramic-coated (0% TiO2) glass of Example 1, and pure TiO2. The FTIR spectra at 1090 cm⁻¹ are... -1 and 1000cm -1Characteristic absorption peaks appeared at the locations, corresponding to the tensile vibrations of Si-O-Si and Si-OH, respectively. These characteristic peaks indicate the presence of silicon in the composite material and suggest the formation of Si-O-Si bonds on the glass surface. These results verify that the introduction of methyltrimethoxysilane, as a known silane coupling agent, can enhance the interfacial adhesion between the coating and the substrate.

[0073] 2) Figure 2 This is a scanning electron microscope image of the ceramic-coated (24% TiO2) glass in Example 4. Figure 2 Figure a shows that the TiO2 nanoparticles have a uniform size distribution, such as Figure 2 As shown in Figure b, the average diameter of the TiO2 nanoparticles is approximately 250 ± 52 nm. To verify the uniform distribution of TiO2 nanoparticles in the ceramic coating, the microstructure of the light-reflecting ceramic coating was further analyzed using scanning electron microscopy. The results... Figure 2 As shown in Figure c, TiO2 nanoparticles are uniformly distributed in the coating, verifying their good incorporation effect.

[0074] 3) Figure 3 The scanning electron microscope (SEM) images of the ceramic-coated (24% TiO2) glass in Example 4 are shown, where a is a magnified SEM image of the coating surface, b is a cross-sectional view of the coating, and cf is the energy dispersive spectroscopy (EDS) image of a. Figure 3 As can be seen, the thickness of the light-reflecting ceramic coating is approximately 74 μm. Magnified SEM images show tight interfaces between the coating layers, verifying the coating's density. Further analysis reveals the uniform distribution of Ti, Si, O, and C within the coating, confirming the successful integration of TiO2 nanoparticles into the ceramic matrix, resulting in a uniform morphology and elemental distribution. Furthermore, the SEM images demonstrate that the reflective coating adheres firmly to the glass substrate, verifying its adhesion and stability.

[0075] 4) Figure 4 Macroscopic comparison images of light-reflecting ceramic coating (24% TiO2) under different test conditions are shown. Figure 4 The image in section ab shows macroscopic images of the coating before and after boiling in water at 100°C for 10 hours. Figure 4 In the image, cd represents a macroscopic image after cross-section and peel tests of the boiled coating using 3M 600 tape; c represents a macroscopic image of the ceramic coating after 100 tape peels; d represents a macroscopic image of the ceramic coating after a scratch test following 100 tape peels. Figure 4 As can be seen from the image, the light-reflecting ceramic coating (24% TiO2) applied to the glass remained intact and showed no obvious damage after being boiled in water at 100°C for 10 hours and subjected to 100 tape peel tests. Figure 4Figure e is a macroscopic image of the pull-out force test of the ceramic coating. Figure e further shows that the light-reflective ceramic coating (24% TiO2) can withstand a tensile force of 5 MPa, demonstrating its good durability and adhesion.

[0076] 5) Indoor simulated house cooling experiment

[0077] Test Method: To demonstrate the effectiveness of the ceramic coating (24% TiO2) in mitigating the greenhouse effect, glass and glass coated with ceramic coatings of different TiO2 concentrations were installed on identical expanded polystyrene (EPS) boxes as light-illuminating windows. To simulate a real-world application, the light intensity was fixed at one sun, and a thermocouple was inserted in the center of each box to measure the internal temperature. A transparent, nail-free adhesive was used to ensure good thermal contact between the glass layer and the roof. The ambient temperature was controlled at 25°C, and a solar simulator was vertically irradiated into the boxes, with the temperature inside both boxes monitored in real time. The setup diagram is shown below. Figure 5 As shown in c.

[0078] Experimental results and conclusions: The results are as follows Figure 5 As shown, Figure 5 In the diagram, ab represents the transmission and absorption maps of glass, pure TiO2, and the light-reflecting ceramic coating (24% TiO2) glass in Example 4 in the ultraviolet-visible-near-infrared region of 200–2500 nm; c represents the indoor simulated house cooling device diagram; d represents the temperature rise curves of the glass box and the ceramic coating (24% TiO2) glass box in Example 4 under one sun at 25°C over time.

[0079] from Figure 5 As shown in Figure d, the average temperature difference between the initial stage and 1 hour was approximately 13°C, confirming the cooling effect of the ceramic coating (24% TiO2). A subsequent 6-hour indoor cooling experiment was conducted, and... Figure 6 The results showed that the temperature difference between the box containing ceramic-coated (24% TiO2) glass and the box containing ordinary glass was approximately 13°C, verifying that ceramic-coated (24% TiO2) glass was the optimal sample.

[0080] 6) Outdoor cooling test

[0081] Test Methods: To verify the practical effectiveness of ceramic-coated glass in cooling applications, an outdoor cooling experiment was conducted. Two sample rooms were used, each with a 2cm thick polystyrene foam base and surrounding environment to reduce heat conduction. The slopes of the sample rooms were covered with glass and ceramic coating, respectively. These sample rooms were placed on a table one meter high to reduce the influence of ground radiation, and solar irradiance was quantified using a power meter. K-type thermocouples were used to measure the temperature inside and around the sample rooms, and an anemometer with a hygrometer was used to monitor outdoor wind speed and ambient humidity. Throughout the experiment, solar irradiance inside the sample rooms, outdoor wind speed, humidity, temperature of the ceramic-coated (24% TiO2) glass sample room, and the temperature of the glass sample room and the ambient temperature were monitored in real time.

[0082] Experimental results and conclusions: Figure 7 The image shows the test results of an outdoor cooling experiment over three days. Figure a shows the change in outdoor light intensity over the three days; figure b shows the change in humidity; figure c shows the change in wind speed; and figure d shows the outdoor temperature (corresponding to the environment in the image), the temperature of the glass house (corresponding to the glass in the image), and the temperature of the glass house with the light-reflecting ceramic coating (24% TiO2). From... Figure 7 As can be seen, due to its excellent thermal insulation performance, the temperature inside the glass box is significantly higher than the ambient temperature, especially under strong light, where it rises by an average of about 17°C over three days due to the greenhouse effect. In contrast, the average temperature inside the ceramic-coated (24% TiO2) glass box is 17°C lower than that inside the glass box, demonstrating a significant cooling effect.

[0083] 7) Cooling power test of ceramic-coated (24% TiO2) glass

[0084] Test Method: Heating efficiency (η) of the ceramic rod (5W): The efficiency of the heating rod was calculated by heating water using the heating rod. Water (80g) was placed in a glass bottle wrapped with insulating foam to prevent heat loss. The water temperature rose from 19°C to 100°C within 30 minutes. The power supply voltage was recorded as 7.5V and the current as 2.15A. Therefore, the thermal efficiency (η) of the ceramic rod can be calculated using the following formula:

[0085]

[0086] In the formula, C p The specific heat of water (4.18 J g) -1 K -1 Let m be the mass of water (80g), ΔT be the temperature difference before and after heating (81), A and I be the power supply voltage (7.5V) and current (2.15A), and t be the heating time (30min). The calculated heating efficiency η of the ceramic rod is 93.3%.

[0087] like Figure 8The setup diagram shows a temperature controlled at 25°C. Glass and ceramic-coated (24% TiO2) glass are mounted on two identical expanded polystyrene (EPS) boxes, serving as light-illuminating windows. A clear, nail-free adhesive is used to ensure good thermal contact between the glass layers and the roof. The light intensity is fixed at one sun. A thermocouple is inserted in the center of each box to measure the internal temperature. Additionally, ceramic heating rods are inserted into the box containing the ceramic coating (24% TiO2). The current and voltage of the portable power supply are adjusted to ensure the temperature inside the two polystyrene foam boxes is uniform. Therefore, the cooling power P is calculated using the following formula:

[0088]

[0089] In the formula, A and I are the power supply voltage and current, and S is the surface area of ​​the ceramic-coated glass.

[0090] Experimental Results and Conclusions: Through calculation, the passive cooling power of the ceramic-coated glass room was determined to be 182 Wm. -2 After taking into account the efficiency of the heating rods, the effective cooling power of a house using coated glass is approximately 169.8 W / m². -2 .

[0091] 8) Electrochemical corrosion test

[0092] The ceramic coating was immersed in a 3.5 wt% NaCl solution, and its corrosion resistance was evaluated using an electrochemical workstation (Gamry Reference 3000). The corrosive medium was a 3.5 wt% NaCl solution, and the working electrode had an exposed area of ​​1 cm². 2 A platinum sheet was used as the counter electrode, and an Ag / AgCl electrode was used as the reference electrode. At 105 Hz-10... -2 EIS was measured within a frequency range of Hz, and polarization curves were obtained relative to the open-circuit potential in the range of -0.25 to 0.25 V at a scan rate of 1 mV / s. The open-circuit potential was measured 30 minutes before the test to ensure system stability.

[0093] Test results are as follows Figure 9 As shown, a is the Tafel curve of ordinary iron sheet and iron sheet with ceramic coating (24% TiO2), b is the Nyquist plot of ordinary iron sheet, c is the Nyquist plot of iron sheet with reflective ceramic coating (24% TiO2), and d is the Bode plot of ordinary iron sheet and iron sheet with light-reflective ceramic coating (24% TiO2).

[0094] Figure 9As shown in Figure a, the anode slope of the ceramic coating is large, while the cathode slope is small, indicating that the circuit density changes slowly with the increase of the cathode branch potential. Table 1 shows the Tafel data parameters of the ceramic coating (24% TiO2) as follows:

[0095] Table 1: Tafel data parameters for ordinary iron sheets and coated iron sheets

[0096]

[0097] As can be seen from the data in Table 1, the i of the coated iron sheet corr 4.890×10 -8 A cm -2 The i is far lower than that of ordinary iron sheets corr This indicates that the coating can effectively reduce the probability and severity of corrosion. For ordinary iron sheets, the EIS spectrum shows a concave semicircle at high frequencies, representing the charge transfer resistance at the electrode / electrolyte interface. Therefore, the equivalent circuit model shown is used for fitting, which consists of a modified Randle circuit. Here, Rs represents the solution resistance, Rct represents the charge transfer resistance at the electrode / electrolyte interface, and the CPE (phase constant element) is used to simulate the behavior of a non-ideal capacitor, such as... Figure 9 As shown in Figures b and c, these are schematic diagrams of equivalent circuit models for fitting the impedance data of ordinary iron sheets and iron sheets coated with ceramic coatings, respectively. The fitting results are shown in Table 2.

[0098] Table 2: EIS data fitting results for ordinary iron sheets and coated iron sheets

[0099]

[0100] Table 2 shows that, compared to the iron sheet, the ceramic-coated iron sheet has a larger capacitor circuit diameter, indicating an increased charge transfer resistance. This is due to the presence of a protective layer at the metal-solution interface. The Rf and Rct of the coated iron sheet are both higher than those of the ordinary iron sheet, while the CPEdl of the coated iron sheet is five orders of magnitude lower. The higher Rct and lower CPEdl indicate that the ceramic coating has better corrosion resistance. Figure 9 (d) shows a Bode diagram of a plain iron sheet and a coated iron sheet. Compared to the plain iron sheet, the coated iron sheet exhibits higher impedance at all frequencies. The impedance modulus |Z| of the coated sample reaches 2.023 × 10⁻⁶. 6 Ωcm 2 The corrosion resistance significantly exceeded that of ordinary iron sheets, further indicating its enhanced corrosion resistance. EIS analysis showed that compared with ordinary iron sheets (CPEdl = 1.670 × 10⁻⁶), the corrosion resistance was significantly higher. -3 F s(1-a)cm -2 Compared to the coated sample, the double-layer capacitance (CPEdl = 1.793 × 10⁻⁶) is significantly higher. -9F s(1-a)cm -2 The contact angle is significantly reduced, reflecting the development of a compact and robust protective barrier. This dense layer reduces the active sites for corrosion reactions and increases the stability of the coating in corrosive environments. The contact angle of the coating of this invention is greater than 90°. Figure 10 It has good hydrophobic properties. For example... Figure 11 As shown in Figure ab, ab is a comparison of the self-cleaning effect of the light-reflecting ceramic coating (24% TiO2) before and after. When riverbed silt is used on the surface of the ceramic coating, the coating surface can self-clean.

[0101] In summary, the light-reflecting ceramic coating prepared by this invention is a titanium dioxide-reinforced ceramic coating with excellent light-reflecting properties, which can effectively improve the passive cooling effect of buildings and significantly reduce energy consumption. This coating not only possesses excellent solar reflectivity, UV stability, and corrosion resistance, but also exhibits high adhesion, excellent wear resistance, and self-cleaning function, maintaining superior performance under long-term UV exposure and harsh outdoor environments. By optimizing the concentration of titanium dioxide, this invention maintains good adhesion and durability on various substrates such as metals, wood, and glass, and has significant resistance to yellowing, maintaining its aesthetic appearance even after long-term use. Therefore, the ceramic coating of this invention is not only suitable for various building materials, but also has broad application prospects in improving building energy efficiency and reducing energy consumption. This invention has strong market application potential and can provide the construction industry with a sustainable, environmentally friendly, and efficient passive cooling solution.

[0102] As described above, although the invention has been shown and described with reference to specific preferred embodiments, it should not be construed as limiting the invention itself. Various changes in form and detail may be made without departing from the spirit and scope of the invention.

Claims

1. A method for producing a corrosion-resistant, self-cleaning, light-reflecting ceramic coating, characterized in that The coating solution is attached to the base material by a doctor blade method to form a corrosion-resistant self-cleaning light-reflecting ceramic coating; The coating solution comprises a silica sol, a silane coupling agent, a wetting agent, tetrafluoroethylene particles, formic acid and titanium dioxide nanoparticles; the content of each component in the coating solution is as follows: The silane coupling agent is 24.5wt.%-42.5wt.%; The silica sol is 40wt.%; The wetting agent is 0.1-0.3wt.%; The polytetrafluoroethylene particles are 5wt.%; The formic acid is 0.3wt.%; The titanium dioxide nanoparticles are 24wt.%; The sum of the mass percentages of the components is 100%.

2. The production method according to claim 1, characterized by, The silane coupling agent is methyltrimethoxysilane; the wetting agent is wetting agent BYK-310; and the titanium dioxide nanoparticles are rutile titanium dioxide with a particle size of 250 nm.

3. The method of claim 1, wherein, The preparation method comprises the following steps: Step one, the silane coupling agent, silica sol, wetting agent, polytetrafluoroethylene particles and formic acid are added to a reagent bottle and mixed uniformly on a shaker at a speed of 3000 rpm to obtain a base solution; Step two, different concentrations of titanium dioxide nanoparticles are added to the base solution, and the mixture is stirred at room temperature for 1 hour to ensure uniform dispersion of the nanoparticles to obtain a coating solution; Step three, the coating solution is uniformly coated on the surface of the base material, and a doctor blade technique is used to adjust the coating thickness; Step four, the coated base is baked at 120°C for 30 minutes to complete the curing of the coating and form a light-reflecting ceramic coating.

4. The production method according to claim 3, characterized by, In step three, the coating thickness is 74 μm, and the coating thickness is achieved by adjusting the gap of the doctor blade.

5. The preparation method according to claim 3, characterized in that, The base material is any one of glass, wood and steel.

6. A corrosion-resistant self-cleaning light-reflecting ceramic coating obtained by the preparation method of any one of claims 1-5.

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