Solar thermal interface evaporation coating and preparation method thereof

Abstract

The present invention discloses a solar thermal interface evaporation coating and a preparation method thereof. The preparation method of the solar thermal interface evaporation coating comprises: wrapping polyaniline or polypyrrole on the surface of microsphere particles to obtain photothermal microsphere particles, wherein the microsphere particles are organic or inorganic microsphere particles with a particle size of 10 to 100 μm; uniformly mixing the photothermal microsphere particles, acrylic resin, dispersant and hydrophilic modifier; the ratio of the mass of acrylic resin to the total volume of the photothermal microsphere particles is 1: (5 to 30) g / cm 3 After the photothermal interface evaporation coating is cured, the photothermal microsphere particles accumulate to form a three-dimensional porous network structure, and the gaps between the photothermal microsphere particles form capillary channels with water transmission capabilities. The present invention does not require an additional three-dimensional porous network structure. The coating formed after the coating is cured not only acts as a photothermal layer to absorb solar energy and convert it into heat energy to drive water evaporation, but also acts as a three-dimensional porous network structure to provide a channel for water transmission, greatly simplifying the structure of the solar interface evaporation device.

Description

Technical Field

[0001] The invention relates to a photothermal interface evaporation coating, in particular to a solar photothermal interface evaporation coating and a preparation method thereof. Background Art

[0002] Interfacial evaporation technology uses thermal energy management to concentrate heat on the evaporation interface to improve evaporation efficiency and produce fresh water efficiently. Compared with traditional bulk heating methods, this technology reduces heat loss caused by convection and thermal radiation with its ingenious thermal insulation layer design and evaporation interface optimization and other thermal energy management methods, effectively avoiding heat loss to the water body and the outer space, significantly improving energy utilization efficiency, and thus promoting the evaporation process of water. Solar interfacial evaporation technology, which uses solar energy as a heat source to drive the interfacial evaporation process, has the advantages of low cost, green and low carbon, and high energy utilization efficiency, and has received special attention.

[0003] The water transfer process of transporting water from the bottom to the evaporation surface is an extremely critical factor in solar interfacial evaporation technology. If the water supply rate is less than the evaporation rate, insufficient water supply will occur, resulting in a decrease in the water content in the evaporator and a decrease in the water evaporation efficiency. In order to achieve a continuous and efficient evaporation process, the water transmission channel needs to be reasonably designed. The current solar interfacial evaporation system is usually complex in the construction of water transmission channels. Some use ready-made three-dimensional porous network structures such as sponges, wood, non-woven fabrics, cotton cores, etc. as water transmission channels, and some use 3D printing to construct water channels, which will increase the complexity of the entire device system and is not conducive to promotion and application. In order to promote the widespread application of solar interfacial evaporation technology in seawater desalination, it is imperative to simplify the construction of the device system. Summary of the invention

[0004] In order to overcome the above-mentioned shortcomings and deficiencies of the prior art, the purpose of the present invention is to provide a method for preparing a solar thermal interface evaporation coating. After the prepared coating is cured, the photothermal microsphere particles themselves accumulate to form a three-dimensional porous network structure, and the gaps between the photothermal microsphere particles form channels with capillary action. The present invention does not require an additional three-dimensional porous network structure. The coating formed after the coating is cured can be used as a photothermal layer to absorb solar energy and convert it into heat energy to drive water evaporation, and can also be used as a three-dimensional porous network structure to provide a channel for water transmission, thereby greatly simplifying the structure of the solar interface evaporation device.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] The present invention provides a method for preparing a solar thermal interface evaporation coating, comprising the following steps:

[0007] A layer of polyaniline or polypyrrole is coated on the surface of the microsphere particles to obtain photothermal microsphere particles; the microsphere particles are organic microsphere particles or inorganic microsphere particles, and the particle size is 10-100 μm;

[0008] The photothermal microsphere particles, acrylic resin, dispersant and hydrophilic modifier are uniformly mixed to obtain a solar photothermal interface evaporation coating; the mass ratio of the acrylic resin to the total volume of the photothermal microsphere particles is 1: (5-30) g / cm 3 Preferably, the ratio of the mass of the acrylic resin to the total volume of the photothermal microsphere particles is 1: (5-10) g / cm 3 More preferably, the ratio of the mass of the acrylic resin to the total volume of the photothermal microsphere particles is 1: (5-7) g / cm 3 ;

[0009] After the photothermal interface evaporation coating is cured, the photothermal microsphere particles accumulate themselves to form a three-dimensional porous network structure, and the gaps between the photothermal microsphere particles form capillary channels with water transmission capabilities.

[0010] Preferably, the hydrophilic modifier is neutral silica sol; and the dispersant is ethanol.

[0011] Preferably, the surface of the microsphere particles is coated with a layer of polyaniline, specifically:

[0012] The microsphere particles are dispersed in pure water or sodium dodecyl sulfate aqueous solution and stirred to form a suspension; aniline and hydrochloric acid are added and stirred evenly, and ammonium persulfate solution is added dropwise during the stirring process, and the reaction is carried out in an ice bath. After centrifugal washing and drying, microsphere particles wrapped with polyaniline are obtained; wherein the mass concentration of the suspension is 3.8~4.2%, the concentration of hydrochloric acid is 0.8~1.2 mol / L, the concentration of ammonium persulfate solution is 0.25~0.35g / ml, and the volume ratio of the suspension, hydrochloric acid, aniline, and ammonium persulfate solution is (11~13):(2.5~3.5):(0.08~0.12):1.

[0013] Preferably, the photothermal microsphere particles are silica microsphere particles wrapped by polyaniline; the particle size of the silica microsphere particles is 10-80 μm; the mass ratio of the photothermal microsphere particles, ethanol and neutral silica sol is (1.8-2.2):(8.8-9.3):1.

[0014] Preferably, the photothermal microsphere particles are polystyrene microsphere particles wrapped by polyaniline; the particle size of the polystyrene microsphere particles is 10-80 μm; the mass ratio of the photothermal microsphere particles, ethanol and neutral silica sol is (0.8-1.2):(8.8-9.3):1.

[0015] The present invention also provides another method for preparing a solar thermal interface evaporation coating, comprising the following steps:

[0016] A layer of polyaniline or polypyrrole is coated on the surface of the microsphere particles to obtain photothermal microsphere particles; the microsphere particles are organic microsphere particles or inorganic microsphere particles, and the particle size is 10-100 μm;

[0017] Coating a hydrophilic silicon dioxide layer on the surface of the photothermal microsphere particles to obtain hydrophilically modified photothermal microsphere particles;

[0018] The hydrophilic modified photothermal microsphere particles, acrylic resin and dispersant are uniformly mixed to obtain a solar photothermal interface evaporation coating; the ratio of the mass of the acrylic resin to the total volume of the hydrophilic modified photothermal microsphere particles is 1: (5-30) g / cm 3 Preferably, the ratio of the mass of the acrylic resin to the total volume of the hydrophilically modified photothermal microsphere particles is 1: (5-10) g / cm 3 More preferably, the ratio of the mass of the acrylic resin to the total volume of the hydrophilically modified photothermal microsphere particles is 1: (5-7) g / cm 3 ;

[0019] After the photothermal interface evaporation coating is cured, the hydrophilically modified photothermal microsphere particles accumulate themselves to form a three-dimensional porous network structure, and the gaps between the hydrophilically modified photothermal microsphere particles form capillary channels with water transmission capabilities.

[0020] Preferably, the surface of the photothermal microsphere particles is coated with a hydrophilic layer of silicon dioxide, and the specific steps are:

[0021] The photothermal microsphere particles are dispersed in a mixed solution of water and ethanol, and ammonia water is added; then, an ethanol solution of tetraethyl silicate is dropped at 45-55°C for reaction, and the photothermal microsphere particles with a surface coated with a hydrophilic layer of silica are obtained after centrifugal washing and drying.

[0022] Preferably, the photothermal microsphere particles are polymethyl methacrylate microsphere particles wrapped by polyaniline; the particle size of the polymethyl methacrylate microsphere particles is 10-50 μm; and the mass ratio of the hydrophilically modified photothermal microsphere particles to the dispersant is 1:(9.5-10).

[0023] The present invention also provides a solar thermal interface evaporation coating, comprising photothermal microsphere particles, acrylic resin, dispersant and hydrophilic modifier; specifically, the photothermal microspheres of the present invention can be carbon black microsphere particles, or microsphere particles with a layer of polyaniline or polypyrrole coated on the surface, or other materials with high solar light absorption rate;

[0024] The hydrophilic modifier is mixed with the photothermal microsphere particles, acrylic resin, and dispersant to form a coating, and the ratio of the mass of the acrylic resin to the total volume of the photothermal microsphere particles is 1: (5-30) g / cm 3 ;

[0025] Alternatively, the hydrophilic modifier is coated with a hydrophilic layer on the surface of the photothermal microsphere particles by a liquid phase coating method to form hydrophilically modified photothermal microsphere particles, and the hydrophilically modified photothermal microsphere particles, acrylic resin, and dispersant are mixed to form a coating, and the ratio of the mass of the acrylic resin to the total volume of the hydrophilically modified photothermal microsphere particles is 1: (5~30) g / cm 3 ;

[0026] After the photothermal interface evaporation coating is cured, the photothermal microsphere particles or the hydrophilically modified photothermal microsphere particles accumulate themselves to form a three-dimensional porous network structure, and the gaps between the photothermal microsphere particles or the gaps between the hydrophilically modified photothermal microsphere particles form capillary channels with water transmission capability.

[0027] The present invention also provides a solar thermal interface evaporation device, comprising an insulating substrate and a solar thermal interface evaporation coating located on the surface of the insulating substrate; the solar thermal interface evaporation coating is obtained by curing the solar thermal interface evaporation coating at room temperature.

[0028] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0029] (1) After the coating of the present invention is cured, the photothermal microsphere particles accumulate themselves to form a three-dimensional porous network structure, and the gaps between the photothermal microsphere particles form channels with capillary action. The present invention does not require an additional three-dimensional porous network structure. The coating formed after the coating is cured can serve as a photothermal layer to absorb solar energy and convert it into heat energy to drive water evaporation, and can also serve as a three-dimensional porous network structure to provide a channel for water transmission, greatly simplifying the structure of the solar interface evaporation device.

[0030] (2) The solar thermal interface evaporation coating of the present invention selects photothermal microsphere particles of appropriate particle size and adds an appropriate amount of acrylic resin, so that some photothermal microsphere particles are tightly bonded to each other, while some photothermal microsphere particles are not bonded to each other and form gaps, thereby forming a three-dimensional porous network structure. The gaps between the photothermal microsphere particles form capillary channels with water transmission capacity, which transmit salt water from the bottom to the top evaporation surface for stable evaporation; at the same time, by adding a hydrophilic modifier, the water transmission capacity of the capillary channels is further improved, thereby improving the evaporation efficiency and stability.

[0031] (3) The solar thermal interface evaporation coating of the present invention can be coated on the surface of any type and shape of thermal insulation materials, and interface evaporation devices of various shapes can be constructed to meet different needs; at the same time, coatings with different evaporation rates can be obtained by selecting the shape of the evaporation interface, preferably a spherical shape.

[0032] (4) The solar thermal interface evaporation coating of the present invention can be cured and formed by simply standing at room temperature. The conditions required are low, the preparation process is simpler, and the solvent is only ethanol, which is safe, green and pollution-free. It is expected to achieve large-scale application in seawater desalination and realize efficient production of fresh water. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a scanning electron microscope photograph of the solar thermal interface evaporation coating after curing prepared in Example 1 of the present invention.

[0034] Figure 2 This is a graph showing the variation of evaporation rate over time in a long-term evaporation experiment of salt water using the solar thermal interface devices prepared in Example 1, Example 2, and Comparative Example 1 of the present invention.

[0035] Figure 3 This is a graph showing the variation of evaporation rate over time in a long-term evaporation experiment of salt water using the solar thermal interface device prepared in Example 3 of the present invention.

[0036] Figure 4 This is a graph showing the variation of evaporation rate over time in a long-term evaporation experiment of salt water using the solar thermal interface device prepared in Example 4 of the present invention.

[0037] Figure 5 This is a graph showing the variation of evaporation rate over time in a long-term evaporation experiment of salt water using the solar thermal interface device prepared in Example 5 of the present invention.

[0038] Figure 6 This is a graph showing the variation of evaporation rate over time in a long-term evaporation experiment of salt water using the solar thermal interface device prepared in Example 6 of the present invention.

[0039] Figure 7 This is a graph showing the variation of evaporation rate over time in a long-term evaporation experiment of salt water using the solar thermal interface device prepared in Example 7 of the present invention. DETAILED DESCRIPTION

[0040] The present invention will be further described in detail below in conjunction with examples, but the embodiments of the present invention are not limited thereto.

[0041] Example 1

[0042] The solar thermal interface evaporation coating of this embodiment is prepared as follows:

[0043] (1) Disperse silica microspheres in pure water and stir to form a suspension, add aniline and hydrochloric acid and stir evenly, slowly drop ammonium persulfate solution into the mixture while stirring, react in an ice bath, centrifuge and wash with water, and dry to obtain silica microsphere particles wrapped by polyaniline, i.e., photothermal microsphere particles. The silica microspheres are 30 μm microsphere particles with uniform particle size distribution, the mass concentration of the silica suspension is 4%, the concentration of hydrochloric acid is 1 mol / L, the concentration of ammonium persulfate solution is 0.3 g / ml, and the volume ratio of silica suspension, hydrochloric acid, aniline, and ammonium persulfate solution is 12:3:0.1:1.

[0044] (2) The silica microsphere particles wrapped by polyaniline, acrylic resin, ethanol and neutral silica sol are mixed evenly to obtain a solar thermal interface evaporation coating. The mass ratio of the silica microsphere particles wrapped by polyaniline, ethanol and neutral silica sol is 2:9.1:1, and the mass ratio of the acrylic resin to the total volume of the silica microsphere particles wrapped by polyaniline is 1:6 g / cm 3 Among them, the brand of neutral silica sol is Yousuo; the brand of acrylic resin is Foshan Juntu, and the model is JT-206.

[0045] The solar thermal interface evaporation coating prepared in this embodiment is brushed on the surface of a glass sheet and left to stand at room temperature until it is completely cured to form a coating. The ethanol in the coating is completely volatilized, and the acrylic resin forms chemical bonds between the photothermal microsphere particles and between the photothermal microsphere particles and the substrate, bonding them tightly together. The morphology is observed under a scanning electron microscope, as shown in FIG. Figure 1 As shown, some photothermal microsphere particles are tightly bonded, while some photothermal microsphere particles are not bonded and form gaps, forming a three-dimensional porous network structure. The gaps between the photothermal microsphere particles form capillary channels with water transmission capabilities (yellow arrows in the figure).

[0046] The construction process of the solar thermal interface device of this embodiment is as follows:

[0047] The solar thermal interface evaporation coating prepared in this embodiment is brushed on the surface of a glass sheet, and left to stand at room temperature until it is completely cured to form a coating, thereby obtaining a plate-shaped thermal interface, which is then fixed on an auxiliary floating thermal insulation material (such as polystyrene foam) to form a plate-shaped thermal interface evaporation device. When in use, the plate-shaped thermal interface is inserted into the water at an angle, with the upper part located above the water surface and the lower part located below the water surface. The plate-shaped thermal interface in the lower part transfers salt water from the lower part to the upper part through the capillary channels formed by the gaps between the thermal microsphere particles, and the plate-shaped thermal interface in the upper part absorbs solar energy, converts the solar energy into thermal energy, and drives water evaporation.

[0048] The solar thermal interface device prepared in this example was placed in a beaker containing a salt solution, and the interface was evaporated under sunlight to test its evaporation rate. Figure 2 As shown in , the solar thermal interface device of this embodiment has a high evaporation rate and can still maintain a stable evaporation rate after long-term illumination.

[0049] Example 2

[0050] The ratio of the mass of the solar thermal interface evaporation coating of this embodiment excluding the acrylic resin to the total volume of the silica microsphere particles wrapped by polyaniline is 1:30 g / cm 3 Otherwise, the preparation process is the same as that of Example 1.

[0051] The solar thermal interface device of this embodiment is constructed in the same manner as in Example 1. The solar thermal interface device prepared in this embodiment is placed in a beaker containing a salt solution, and the interface is evaporated under sunlight to test its evaporation rate. The results are as follows: Figure 2 As shown, it can be seen that after long-term illumination, the solar thermal interface device of this embodiment can still maintain a relatively stable evaporation rate, but the evaporation rate is lower than that of Example 1 and the stability is slightly worse.

[0052] Comparative Example 1

[0053] The ratio of the mass of the solar thermal interface evaporation coating of this comparative example except the mass of the acrylic resin to the total volume of the silica microsphere particles wrapped by polyaniline is 1:1.2 g / cm 3 Otherwise, the preparation process is the same as that of Example 1.

[0054] The solar thermal interface device of this embodiment is constructed in the same manner as in Example 1. The solar thermal interface device prepared in this embodiment is placed in a beaker containing a salt solution, and the interface is evaporated under sunlight to test its evaporation rate. The results are as follows: Figure 2 As shown, it can be seen that the evaporation rate of the solar thermal interface device of this embodiment is low, and the stability is also poor after long-term illumination.

[0055] It can be seen from Examples 1 and 2 and Comparative Example 1 that the ratio of the mass of acrylic resin to the total volume of the silica microsphere particles wrapped by polyaniline is 1:6 g / cm 3 For the optimal ratio, the amount of acrylic resin added plays a crucial role in the formation of capillary channels and water transmission capacity.

[0056] Example 3

[0057] The preparation process of the solar thermal interface evaporation coating of this embodiment is the same as that of embodiment 1, except that the silicon dioxide microspheres are 50 μm microsphere particles with uniform particle size distribution.

[0058] The solar thermal interface device of this embodiment is constructed in the same manner as in Example 1. The solar thermal interface device prepared in this embodiment is placed in a beaker containing a salt solution, and the interface is evaporated under sunlight to test its evaporation rate. The results are as follows: Figure 3 As shown. Figure 3 It can be seen that the solar thermal interface device of this embodiment has a high evaporation rate and can still maintain a stable evaporation rate after long-term illumination.

[0059] Example 4

[0060] The solar thermal interface evaporation coating of this embodiment is the same as that of embodiment 3.

[0061] The construction process of the solar thermal interface device of this embodiment is as follows:

[0062] The solar thermal interface evaporation coating was brushed onto the surface of the spherical foam and allowed to stand at room temperature until the coating was completely cured to form a spherical thermal interface evaporation device. The solar thermal interface device prepared in this embodiment was placed in a beaker containing a salt solution and subjected to interface evaporation under sunlight. The evaporation rate was tested. The results were as follows: Figure 4 As shown. Figure 4 It can be seen that the evaporation rate of the solar thermal interface device of this embodiment is higher than that of the embodiment 3, and the evaporation rate can still be kept stable after long-term illumination.

[0063] Example 5

[0064] The solar thermal interface evaporation coating of this embodiment is prepared as follows:

[0065] (1) Disperse polystyrene microspheres in pure water and stir to form a suspension, add aniline and hydrochloric acid and stir evenly, slowly drop ammonium persulfate solution into the mixture while stirring and react in an ice bath, centrifuge, wash with water and dry to obtain polystyrene microsphere particles wrapped by polyaniline. The polystyrene microspheres are 20 μm microsphere particles with uniform particle size distribution, the mass concentration of the polystyrene suspension is 4%, the concentration of hydrochloric acid is 1 mol / L, the concentration of ammonium persulfate solution is 0.3 g / ml, and the volume ratio of the polystyrene suspension, hydrochloric acid, aniline and ammonium persulfate solution is 12:3:0.1:1.

[0066] (2) The polystyrene microsphere particles wrapped by polyaniline, acrylic resin, ethanol and neutral silica sol are mixed evenly to obtain a solar thermal interface evaporation coating. The mass ratio of the polystyrene microsphere particles wrapped by polyaniline, ethanol and neutral silica sol is 1:9.1:1, and the mass ratio of the acrylic resin to the total volume of the polystyrene microsphere particles wrapped by polyaniline is 1:6 g / cm 3 Among them, the brand of neutral silica sol is Yousuo; the brand of acrylic resin is Foshan Juntu, and the model is JT-206.

[0067] The construction process of the solar thermal interface device of this embodiment is as follows:

[0068] The solar thermal interface evaporation coating prepared in this example was brushed onto the surface of the spherical foam and allowed to stand at room temperature until the coating was completely cured to form a spherical thermal interface evaporation device. The solar thermal interface device prepared in this example was placed in a beaker containing a salt solution and subjected to interface evaporation under sunlight. The evaporation rate was tested. The results were as follows: Figure 5 As shown. Figure 5 It can be seen that the solar thermal interface device of this embodiment has a high evaporation rate and can still maintain a stable evaporation rate after long-term illumination.

[0069] Example 6

[0070] The solar thermal interface evaporation coating of this embodiment is prepared as follows:

[0071] (1) Disperse polymethyl methacrylate microspheres in sodium dodecyl sulfate aqueous solution and stir to form an emulsion, add aniline and hydrochloric acid and stir evenly, slowly drop ammonium persulfate solution into the mixture during stirring and react in an ice bath, centrifuge, wash with water and dry to obtain polymethyl methacrylate microsphere particles wrapped by polyaniline, i.e., photothermal microsphere particles. The polymethyl methacrylate microsphere particles are 20 μm microsphere particles with uniform particle size distribution, the concentration of sodium dodecyl sulfate aqueous solution is 0.25%, the mass concentration of polymethyl methacrylate emulsion is 4%, the concentration of hydrochloric acid is 1 mol / L, the concentration of ammonium persulfate solution is 0.3 g / ml, and the volume ratio of polymethyl methacrylate emulsion, hydrochloric acid, aniline and ammonium persulfate solution is 12:3:0.1:1.

[0072] (2) The polymethyl methacrylate microsphere particles coated with polyaniline are dispersed in a mixed solution of water and ethanol, ammonia water is added, and then an ethanol solution of tetraethyl silicate is slowly dropped at 50°C for reaction, and after centrifugal washing and drying, polymethyl methacrylate microsphere particles coated with polyaniline and loaded with a hydrophilic layer of silica on the surface are obtained, i.e., hydrophilically modified photothermal microsphere particles. The volume ratio of ammonia water to tetraethyl silicate is 4:1.

[0073] (3) The hydrophilically modified photothermal microsphere particles, acrylic resin and ethanol are mixed evenly to obtain a solar thermal interface evaporation coating. The mass ratio of the hydrophilically modified photothermal microsphere particles to ethanol is 1:9.85, and the mass ratio of the acrylic resin to the total volume of the hydrophilically modified photothermal microsphere particles is 1:6 g / cm 3 The brand of acrylic resin is Foshan Juntu and the model is JT-206.

[0074] The construction process of the solar thermal interface device of this embodiment is as follows:

[0075] The solar thermal interface evaporation coating was brushed onto the surface of the spherical foam and left to stand at room temperature until the coating was completely cured to form a spherical thermal interface evaporation device. The prepared device was placed in a beaker containing a salt solution and subjected to interface evaporation under sunlight. The evaporation rate was tested. The results are as follows: Figure 6 As shown. Figure 6 It can be seen that the solar thermal interface device of this embodiment has a high evaporation rate and can still maintain a stable evaporation rate after long-term illumination.

[0076] Example 7

[0077] The solar thermal interface evaporation coating of this embodiment is the same as that of embodiment 6.

[0078] The construction process of the solar thermal interface device of this embodiment is as follows:

[0079] The solar interface evaporation coating is brushed on the conical foam surface. After the coating is completely cured, a conical photothermal interface evaporation device is formed. The prepared device is placed in a beaker containing a salt solution and the interface is evaporated under sunlight. The evaporation rate is tested. The results are as follows: Figure 7 As shown. Figure 7 It can be seen that the evaporation rate of the solar thermal interface device of this embodiment is relatively high, but lower than that of Example 6. After long-term illumination, it can still maintain a stable evaporation rate.

[0080] In the above embodiments, the photothermal microspheres may also be carbon black microsphere particles, or organic microsphere particles or inorganic microsphere particles with polypyrrole coated on the surface, or other materials with high solar light absorption rate.

[0081] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A method for preparing a solar thermal interface evaporation coating, characterized in that: The following steps are involved: A layer of polyaniline or polypyrrole is coated on the surface of the microsphere particles to obtain photothermal microsphere particles; the microsphere particles are organic microsphere particles or inorganic microsphere particles, and the particle size is 10-100 μm; Coating a hydrophilic silicon dioxide layer on the surface of the photothermal microsphere particles to obtain hydrophilically modified photothermal microsphere particles; The hydrophilic modified photothermal microsphere particles, acrylic resin and dispersant are uniformly mixed to obtain a solar photothermal interface evaporation coating; the ratio of the mass of the acrylic resin to the total volume of the hydrophilic modified photothermal microsphere particles is 1: (5-30) g / cm 3 ; After the solar thermal interface evaporation coating is cured, the hydrophilically modified photothermal microsphere particles accumulate themselves to form a three-dimensional porous network structure, and the gaps between the hydrophilically modified photothermal microsphere particles form capillary channels with water transmission capabilities.

2. The method for preparing the solar thermal interface evaporation coating according to claim 1, characterized in that: The specific steps of wrapping a hydrophilic layer of silicon dioxide on the surface of the photothermal microsphere particles are as follows: The photothermal microsphere particles are dispersed in a mixed solution of water and ethanol, and ammonia water is added; then, an ethanol solution of tetraethyl silicate is dropped at 45-55°C for reaction, and the photothermal microsphere particles with a surface coated with a hydrophilic layer of silica are obtained after centrifugal washing and drying.

3. The method for preparing the solar thermal interface evaporation coating according to claim 1, characterized in that: The photothermal microsphere particles are polymethyl methacrylate microsphere particles wrapped by polyaniline; the particle size of the polymethyl methacrylate microsphere particles is 10-50 μm; the mass ratio of the hydrophilically modified photothermal microsphere particles to the dispersant is 1: (9.5-10).

4. Solar thermal interface evaporation coating, characterized in that: The coating is prepared by the method for preparing the solar thermal interface evaporation coating according to any one of claims 1 to 3.

5. Solar thermal interface evaporation device, characterized in that: It comprises a heat-insulating substrate and a solar thermal interface evaporation coating located on the surface of the heat-insulating substrate; the solar thermal interface evaporation coating is obtained by curing the solar thermal interface evaporation coating according to claim 4 at room temperature.

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