Coupling wedge structures, two-dimensional tip patterns, and three-dimensional tapered pillars of water harvesting surfaces

Abstract

The application relates to a water collecting surface coupling a wedge structure, a two-dimensional tip pattern and a three-dimensional conical column, comprising a two-dimensional tip patterned surface composed of a plurality of super-hydrophilic regions and super-hydrophobic regions in a tip structure and being distributed between the super-hydrophilic regions and the super-hydrophobic regions, the super-hydrophilic regions being provided with a plurality of wedge structures and standing three-dimensional conical columns, the side of the three-dimensional conical column being provided with a longitudinal groove, the surface of the wedge structure and the three-dimensional conical column being covered with a super-hydrophilic coating, and the surface of the super-hydrophobic region being covered with a super-hydrophobic coating, the two-dimensional tip patterned surface capable of guiding directional transportation and collection of water, the three-dimensional conical column for capturing water droplets and the wedge structure being combined into a multi-stage structure inspired by a plurality of biological prototypes, so that the adhesion of water droplets is solved, small water droplets can be quickly absorbed and timely and directionally transported for efficient water collection, and the water collection efficiency reaches 3.7 / h / cm. 2 The above can be one-time formed by 3D printing, is simple to process, is stable in structure and performance, can be recycled multiple times, and is beneficial to popularization and application.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of water collection, and particularly relates to a water collection surface coupled with a wedge structure, a two-dimensional tip pattern and a three-dimensional conical column and a preparation method thereof. BACKGROUND

[0002] With the development of population, economy and global warming, the demand for fresh water by human beings is becoming more and more urgent, which is particularly crucial in arid and semi-arid environments, and therefore, water collection has important practical significance for solving the water for living and production and emergency water supply after disasters in global arid regions. The research on application of a bionic structure to a water collection surface in the prior art has made certain progress, such as a two-dimensional water collection surface simulating a desert beetle formed by constructing a hydrophilic and hydrophobic combined pattern on a plane, although the hydrophobic area can drive water droplets to the hydrophilic area to realize directional transport of the water droplets, but its main defect is that in the hydrophilic area, small water droplets slowly gather, and a large surface tension will cause the water droplets to adhere to the hydrophilic surface, and only when the gravity of the water droplets is greater than the adhesion, the water droplets will slide down, in this process, the water droplets cover the water collection surface all the time, so that the water collection surface temporarily loses the water collection ability, and the continuous collection of water droplets is affected by time, which significantly reduces the water collection efficiency. Therefore, to develop a high-efficiency water collection system, it is necessary to improve the water collection efficiency of the water collection surface and timely transport and collect the water droplets so as to release the water collection surface to start the next round of water droplet collection.

[0003] Secondly, the microstructure of the traditional water collection surface synthesized by chemical synthesis or physically grown has problems of unstable surface structure and performance, complicated processing, inability to be recycled multiple times, environmental pollution and the like. SUMMARY

[0004] The present application aims to at least solve one of the above technical problems to some extent, and provides a water collection surface coupled with a wedge structure, a two-dimensional tip pattern and a three-dimensional conical column and a preparation method thereof, which can solve the problem of adhesion of water droplets, quickly adsorb small water droplets in the air, timely transport and collect the water droplets, significantly improve the water collection efficiency, has more stable surface structure and performance, can be recycled multiple times, has no pollution to the environment, is easy to process and maintain, and is conducive to popularization and application in the field of water collection.

[0005] The technical scheme adopted by the present application to solve the technical problems is as follows:

[0006] A water collecting surface coupling wedge-shaped structure, two-dimensional tip pattern and three-dimensional conical column, comprising a two-dimensional tip patterned surface, the two-dimensional tip patterned surface comprising a plurality of super-hydrophilic regions and super-hydrophobic regions in tip structure and inter-distributed, the super-hydrophilic regions being provided with a plurality of wedge-shaped structures and standing three-dimensional conical columns, the heads of the plurality of wedge-shaped structures being unidirectionally and continuously spread towards the bottom end of the super-hydrophilic regions, the side of the three-dimensional conical column being provided with longitudinal grooves, the surfaces of the wedge-shaped structures and three-dimensional conical columns being covered with super-hydrophilic coating, and the surface of the super-hydrophobic regions being covered with super-hydrophobic coating.

[0007] Further, the tip angle of the super-hydrophilic regions and super-hydrophobic regions is 5°-30°, the bottom end diameter of the three-dimensional conical column is 50μm-500μm, the height of the three-dimensional conical column is 80μm-1400μm, and the number of longitudinal grooves is 2-8.

[0008] If the tip angle of the super-hydrophilic regions and super-hydrophobic regions is too small, it is not conducive to the directional transport and coating of larger water droplets, and if the tip angle is too large, it is not conducive to the directional transport of water droplets by Laplace pressure; if the bottom end diameter of the three-dimensional conical column is too small, it is not conducive to the aggregation of small water droplets on the three-dimensional conical column and the processing of the water collecting surface, and if the bottom end diameter is too large, it is not conducive to the adsorption and directional transport of small water droplets on the three-dimensional conical column, and it leads to a decrease in the number of three-dimensional conical columns per unit water collecting area; if the height of the three-dimensional conical column is too large, it increases the evaporation loss of water droplets during transport, and if the height of the three-dimensional conical column is too small, it is not conducive to the three-dimensional conical column to provide sufficient paths for the adsorption, aggregation and directional transport of water droplets; if the number of longitudinal grooves is too large, it reduces the transport efficiency of water droplets from the three-dimensional conical column to the wedge-shaped structure, and if the number of longitudinal grooves is too small, it reduces the efficiency of adsorption, aggregation and directional transport of water droplets on the three-dimensional conical column; therefore, through optimization of various parameters, the water collecting efficiency of the water collecting surface can reach 3.7 / h / cm 2 above.

[0009] Further, the tip angle of the super-hydrophilic regions and super-hydrophobic regions is preferably 10°-20°, and the water collecting efficiency of the water collecting surface is 4.0 g / h / cm 2 above.

[0010] Further, the three-dimensional conical column stands above the wedge-shaped structure, which is conducive to fully exerting the directional transport effect of the wedge-shaped structure.

[0011] Further, the tip angle of the super-hydrophilic regions and super-hydrophobic regions is preferably 15°-20°, the bottom end diameter of the three-dimensional conical column is preferably 100μm-400μm, the height of the three-dimensional conical column is preferably 200μm-1400μm, and the water collecting efficiency of the water collecting surface is 4.7 g / h / cm 2 above.

[0012] Further, the longitudinal grooves are extended from the three-dimensional cylindrical column tip to the root by the capillary force to further improve the absorption, fusion and directional transport of water droplets, so that the tiny water droplets in the air are absorbed on the three-dimensional conical column tip and fused to grow and are transported directionally from the tip to the root.

[0013] Further, the number of longitudinal grooves is preferably 4-6, the height of the three-dimensional conical column is preferably 200μm-1000μm, and the water collection efficiency of the water collection surface is 6.5 g / h / cm 2 The above.

[0014] Further, the wedge-shaped structure has a cavity wedge angle of 30°-65°, a body length of 300μm-720μm, a pull-up length of 360μm-650μm, an elliptical semi-major axis length of 500μm-900μm, and a cavity length of 650μm-900μm, which can transfer water droplets directionally and timely to release the water collection area of the device to enter the next round of water collection cycle.

[0015] Further, the two-dimensional tip patterned surface is used for the collection and transport of water droplets, the tip of the super-hydrophilic region is adjacent to the bottom end of the super-hydrophobic region, and the bottom end of the super-hydrophilic region is adjacent to the tip of the super-hydrophobic region.

[0016] Further, the super-hydrophobic region is provided with a plurality of spaced recesses to further improve the super-hydrophobic properties of the super-hydrophobic region.

[0017] Further, the diameter of the recess is 200μm-400μm, the depth is 50μm-200μm, and the spacing between adjacent recesses is 200μm-400μm.

[0018] Further, the super-hydrophilic coating is prepared by cross-linking polyvinyl alcohol and tannic acid, and the hydrogen bond cross-linking between polyvinyl alcohol PVA and tannic acid TA forms a hydrogel coating, which can further improve the super-hydrophobic properties of the super-hydrophilic region.

[0019] Further, the super-hydrophobic coating includes fluorinated SiO2 nanoparticles modified by tetraethoxysilane and H,1H,2H,2H-perfluorodecyltriethoxysilane, the SiO2 nanoparticles provide roughness for the preparation of the super-hydrophobic coating, and the tetraethoxysilane and H,1H,2H,2H-perfluorodecyltriethoxysilane modify the SiO2 nanoparticles as low-surface-energy substances, which can further improve the super-hydrophobic properties of the super-hydrophobic region.

[0020] A preparation method of a water collection surface coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column, which method comprises:

[0021] Preparation of the substrate: a substrate of 3D printing coupled wedge-shaped structures, a two-dimensional tip pattern including several super-hydrophilic and super-hydrophobic regions in tip structure and inter-distributed, and three-dimensional conical columns, the wedge-shaped structures are several, the heads of the several wedge-shaped structures are unidirectionally and continuously spread toward the bottom of the super-hydrophilic region, and the three-dimensional conical columns are several and respectively stand in the super-hydrophilic region, and the three-dimensional conical columns are provided with several longitudinal grooves on the side surface;

[0022] Coating: coating the super-hydrophilic region of the substrate with super-hydrophilic paint; coating the super-hydrophobic region of the substrate with super-hydrophobic paint; forming a super-hydrophilic coating layer on the surface of the wedge-shaped structure and the three-dimensional conical column, and after forming a super-hydrophobic coating layer on the surface of the super-hydrophobic region, a water collecting surface is obtained.

[0023] Further, the substrate is prepared by one-step molding of 3D printing resin material by using a light-cured 3D printer, and after 3D printing, the substrate is ultrasonically rinsed with deionized water and ethanol respectively and dried to obtain a clean substrate surface, which is beneficial to further coating.

[0024] Further, when coating the super-hydrophilic paint, the tip pattern with the same size as the super-hydrophobic region is used as a mask for aligning the super-hydrophobic region; and when coating the super-hydrophobic paint, the tip pattern with the same size as the super-hydrophilic region is used as a mask for aligning the super-hydrophilic region.

[0025] Further, the method comprises:

[0026] Preparation of the super-hydrophilic paint: polyvinyl alcohol and tannic acid are dissolved in a solvent to obtain a mixed solution A, the mass fraction of the polyvinyl alcohol in the mixed solution A is 1%-10%, the mass fraction of the tannic acid in the mixed solution A is 1%-10%, the mixed solution A is fully stirred at 70-90 o C to obtain a PVA-TA hydrogel paint as the super-hydrophilic paint;

[0027] Spraying the super-hydrophilic paint on the super-hydrophilic region of the substrate and drying to form a super-hydrophilic coating layer.

[0028] Further, the mixed solution A is stirred at 70-90 o C for 3-6 hours.

[0029] Further, the solvent for preparing the mixed solution A is composed of deionized water and ethanol in a volume ratio of 1:1.

[0030] Further, the method comprises:

[0031] Preparation of super-hydrophobic coating: uniformly disperse SiO2 nanoparticles in a solvent and adjust pH to obtain a mixed solution B, the mass fraction of SiO2 nanoparticles in the mixed solution B is 10%-25%, add tetraethoxysilane and H,1H,2H,2H-perfluorodecyltriethoxysilane into the mixed solution B to obtain a mixed solution C, the volume fraction of the tetraethoxysilane in the mixed solution C is 2%-6%, the volume fraction of the H,1H,2H,2H-perfluorodecyltriethoxysilane in the mixed solution C is 1%-4%, and the mixed solution C is fully stirred to obtain a fluorinated SiO2 nanoparticle suspension as the super-hydrophobic coating;

[0032] The super-hydrophobic coating is coated on the super-hydrophobic area of the substrate, and is dried to form a super-hydrophobic coating layer.

[0033] Further, the solvent for preparing the mixed solution B is anhydrous ethanol, the pH is adjusted by using an ammonia solution, and the mixed solution B is stirred at room temperature for 30-60 min and ultrasonically stirred for 5-10 min, and the volume fraction of the ammonia solution in the mixed solution B is 5-10%, and the mixed solution C is stirred for 2-4 h.

[0034] Compared with the prior art, the present application has the following beneficial effects:

[0035] (1) In the water collecting process of the water collecting surface: the super-hydrophilic area of the two-dimensional tip patterned surface is modified by a super-hydrophilic coating to increase the super-hydrophilic property, the micro water droplets are quickly adsorbed and captured by the three-dimensional conical columns standing above the wedge-shaped structure, the capillary force generated by the longitudinal grooves makes the micro water droplets quickly directional transport along the tip to the root of the three-dimensional conical column and coalesce into large water droplets, solving the problem of water droplet adhesion and quickly adsorbing micro water droplets in the air.

[0036] The two-dimensional tip patterned surface adopts super-hydrophilic areas and super-hydrophobic areas distributed alternately to form a hydrophilic-hydrophobic interfacial wetting property, the super-hydrophobic area is modified by a super-hydrophobic coating to increase the super-hydrophobic property, so that the super-hydrophobic area can quickly drive water droplets to the super-hydrophilic area, which is beneficial to the detachment of water, and the water droplets on the surface of the super-hydrophilic area are transported from the tip to the bottom under the driving of the Laplace pressure generated by the tip geometry, cooperating with the wedge-shaped structure of the super-hydrophilic area, the capillary force of the wedge-shaped structure realizes the quick directional transport of the water droplets from the tip to the bottom of the super-hydrophilic area, timely transfers the water droplets, releases the water collecting area of the water collecting surface to enter the next round of water collecting cycle, and ensures the continuous collection of water droplets without being affected by time, which proves the stability of water droplet collection and improves the water collecting efficiency.

[0037] In summary, by the three-dimensional conical column for capturing water droplets, the two-dimensional tip patterned surface and the wedge structure that can guide the directional transport and collection of water, the coupling multi-level structure inspired by various biological prototypes can solve the adhesion problem of water droplets, quickly absorb the tiny water droplets in the air, and timely transport and collect the water droplets to a certain area, so that efficient water collection is realized, and the water collection efficiency can reach 3.7 / h / cm 2 Therefore, the efficiency is much higher than that of the traditional water collection surface.

[0038] (2) The preparation method of the water collection surface is to prepare the coupling substrate by 3D printing, so that the three-dimensional conical column structure is regular, ordered and firmly combined with the substrate, the processing is simple, the environment is not polluted, and compared with the traditional water collection surface with chemically synthesized or physically grown microstructure, the water collection efficiency basically remains unchanged after at least 20 cycles of tests, the surface structure and performance are more stable, the maintenance cost is low, the investment is low, the continuous output is high, the problems existing in the traditional water collection surface are overcome, and the method is suitable for solving the inconvenient water resource transport and deployment and large transport cost engineering.

[0039] (3) Further optimization of the tip angle of the super-hydrophilic area and the super-hydrophobic area, the bottom diameter of the three-dimensional conical column, the height of the three-dimensional conical column, and the number of longitudinal grooves, the water collection efficiency of the water collection surface can reach 7.5g / h / cm 2 . BRIEF DESCRIPTION OF DRAWINGS

[0040] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the following drawings of which:

[0041] Figure 1 is a water collection schematic diagram of the water collection surface prepared by the embodiment of the present application;

[0042] Figure 2 is a two-dimensional tip pattern structure diagram of the present application;

[0043] Figure 3 is a two-dimensional tip pattern top view of the present application;

[0044] Figure 4 is a photograph of the water collection surface of the present application and an optical electron microscope;

[0045] Figure 5 is a bottom view of the wedge structure of the present application;

[0046] Figure 6 is an AA direction sectional view of the present application Figure 5 ;

[0047] Figure 7 is a side view photograph of the water collection surface of the present application

[0048] Figure 8 is a perspective view of the three-dimensional conical column of the present application;

[0049] Figure 9 is a perspective view of the three-dimensional conical column of the present application;

[0050] Figure 10 is a perspective view of the three-dimensional conical column of the present application.

[0051] Marked in the figure: super-hydrophilic region-1, super-hydrophobic region-2, super-hydrophilic region and super-hydrophobic region tip angle-θ1, wedge structure-3, cavity wedge angle-θ2, body length-L2, pull-up length-L3, elliptical semi-axis length-L1, cavity length-L4, three-dimensional conical column-4, bottom end diameter-R, longitudinal groove-5, dimple-6, arrow indicates water collection direction, water-7, Figure 4 a represents the optical electron microscope photo of the super-hydrophilic region wedge structure, Figure 4 b represents the optical electron microscope photo of the super-hydrophobic region. DETAILED DESCRIPTION

[0052] The embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation of the present application.

[0053] The materials or reagents used in the following examples and comparative examples are described as follows:

[0054] Resin material: HTL high-temperature resistant photosensitive resin material, heat distortion temperature is 142℃, purchased from Chongqing Mofang Precision Technology Co., Ltd.

[0055] Super-hydrophilic coating: 3.0 g of polyvinyl alcohol PVA and 3.0 g of tannic acid TA were dissolved in 94.0 g of solvent, the solvent was deionized water and anhydrous ethanol in a volume ratio of 1:1, and the solution was stirred at 90 o C for 6h, and a PVA-TA hydrogel coating was obtained as a super-hydrophilic coating.

[0056] Superhydrophobic coating: 6.0 g of SiO2 nanoparticles with a diameter of 10-20 nm were uniformly dispersed in 44 ml of anhydrous ethanol and 6 mL of an ammonia solution with a concentration of 5-10 wt%, and the mixture was uniformly mixed by magnetic stirring at room temperature for 30 min and then ultrasonic stirring for 5 min. Then, 1.0 ml of tetraethoxysilane (TEOS) with a purity of 99.9% and 0.5 mL of H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTES) with a purity of 97% were added, and the mixture was magnetically stirred for 2 h to obtain a fluorinated SiO2 nanoparticle suspension as a superhydrophobic coating.

[0057] The simulated fog environment used in the following examples and comparative examples is described as follows: a fog environment with a humidity of 95% was constructed in a closed environment using a humidifier.

[0058] Example 1

[0059] A method for preparing a water-collecting surface coupled with a wedge-shaped structure, a two-dimensional tip pattern, and a three-dimensional conical column, the method comprising:

[0060] S1, preparing a substrate: printing a resin material using a photocuring 3D printer to prepare a substrate coupled with a wedge-shaped structure, a two-dimensional tip pattern, and a three-dimensional conical column in one piece, the two-dimensional tip pattern comprising a plurality of superhydrophilic regions and superhydrophobic regions distributed between each other in a tip structure, and the tip angle θ1 of the superhydrophilic regions and superhydrophobic regions being 5°;

[0061] The wedge-shaped structure has a plurality of wedge-shaped structures, and the heads of the plurality of wedge-shaped structures are unidirectionally and continuously spread toward the bottom end of the superhydrophilic region, the cavity wedge angle θ2 of the wedge-shaped structure is 30°, the body length L2 is 400 μm, the pull-up length L3 is 400 μm, the elliptical semi-major axis length L1 is 820 μm, and the cavity length L4 is 820 μm;

[0062] The three-dimensional conical column has a plurality of three-dimensional conical columns, and the plurality of three-dimensional conical columns respectively stand above the wedge-shaped structures, the bottom end diameter R of the three-dimensional conical column is 100 μm, the height of the three-dimensional conical column is 200 μm, the three-dimensional conical column is provided with a longitudinal groove, the number of the longitudinal groove is 3, and the longitudinal groove extends from the tip of the three-dimensional column to the root;

[0063] The superhydrophobic region is provided with a plurality of spaced recesses, the diameter of the recess is 200 μm, the depth is 50 μm, and the distance between adjacent recesses is 200 μm;

[0064] After 3D printing, the substrate was ultrasonically rinsed with deionized water and ethanol for 20 min, and then naturally dried to obtain the substrate;

[0065] S2, coating: using the tip pattern consistent with the size of the super-hydrophobic region as a mask to align the super-hydrophobic region, spraying super-hydrophilic paint on the super-hydrophilic region of the substrate in step S1; using the tip pattern consistent with the size of the super-hydrophilic region as a mask to align the super-hydrophilic region, coating super-hydrophobic paint on the super-hydrophobic region of the substrate in step S1; drying in air to form a super-hydrophilic coating on the surface of the wedge structure and the three-dimensional conical column, and after the super-hydrophobic coating on the surface of the super-hydrophobic region, a water collecting surface is obtained.

[0066] Water collecting performance test: the prepared water collecting surface is taken to test water collecting in a simulated fog environment, and the water collecting efficiency is 3.7 g / h / cm 2 After 20 cycles of test, the water collecting efficiency remains at about 3.6 g / h / cm 2 .

[0067] Example 2:

[0068] A method for preparing a water collecting surface coupled with a wedge structure, a two-dimensional tip pattern and a three-dimensional conical column, the method comprising:

[0069] S1, preparing a substrate: using a light-cured 3D printer to print a resin material to prepare a substrate coupled with a wedge structure, a two-dimensional tip pattern and a three-dimensional conical column in one step, the two-dimensional tip pattern comprising a plurality of super-hydrophilic regions and super-hydrophobic regions in a tip structure and distributed between each other, and the tip angle θ1 of the super-hydrophilic regions and the super-hydrophobic regions being 12°;

[0070] The wedge structure has a plurality of heads that are unidirectionally and continuously spread towards the bottom end of the super-hydrophilic region, the cavity wedge angle θ2 of the wedge structure is 30°, the body length L2 is 400 μm, the pull-up length L3 is 400 μm, the elliptical semi-major axis length L1 is 820 μm, and the cavity length L4 is 820 μm;

[0071] The three-dimensional conical column has a plurality of three-dimensional conical columns that stand above the wedge structure, the bottom end diameter R of the three-dimensional conical column is 100 μm, the height of the three-dimensional conical column is 200 μm, the three-dimensional conical column is provided with a longitudinal groove, the number of the longitudinal groove is 3, and the longitudinal groove extends from the tip of the three-dimensional column to the root;

[0072] The super-hydrophobic region is provided with a plurality of spaced recesses, the diameter of the recess is 200 μm, the depth is 50 μm, and the distance between adjacent recesses is 200 μm;

[0073] After 3D printing, the substrate is ultrasonically rinsed with deionized water and ethanol for 20 min, and naturally dried to obtain the substrate;

[0074] S2, coating: using the tip pattern consistent with the size of the super-hydrophobic region as a mask to align the super-hydrophobic region, spraying super-hydrophilic paint on the super-hydrophilic region of the substrate in step S1; using the tip pattern consistent with the size of the super-hydrophilic region as a mask to align the super-hydrophilic region, coating super-hydrophobic paint on the super-hydrophobic region of the substrate in step S1; drying in air to form a super-hydrophilic coating on the surface of the wedge structure and the three-dimensional conical column, and after the super-hydrophobic coating on the surface of the super-hydrophobic region, a water collecting surface is obtained.

[0075] Water collecting performance test: the prepared water collecting surface is taken to test water collecting in a simulated fog environment, and the water collecting efficiency is 4.6 g / h / cm 2 After 20 cycles of testing, the water collecting efficiency remains at about 4.5 g / h / cm 2 .

[0076] Comparative Example 1

[0077] A method for preparing a water collecting surface, which is different from Example 2 in that the tip angle θ1 of the super-hydrophilic region and the super-hydrophobic region is 3°, and the prepared water collecting surface is taken to test water collecting in a simulated fog environment, and the water collecting efficiency is 1.6 g / h / cm 2 After 20 cycles of testing, the water collecting efficiency remains at about 1.5 g / h / cm 2 .

[0078] The comparison results of Example 2 and Comparative Example 1 show that the tip angle of the super-hydrophilic region and the super-hydrophobic region of the two-dimensional tip patterned surface is too small, which is not conducive to the directional transport of larger water droplets, and the area of the super-hydrophilic region and the super-hydrophobic region is small, so that the super-hydrophilic coating and the super-hydrophobic coating will cover each other during spraying, resulting in a significant decrease in water collecting efficiency.

[0079] Example 3

[0080] A method for preparing a water collecting surface coupled with a wedge structure, a two-dimensional tip pattern and a three-dimensional conical column, the method comprising:

[0081] S1, preparing a substrate: using a light-cured 3D printer to print a resin material to prepare a substrate coupled with a wedge structure, a two-dimensional tip pattern and a three-dimensional conical column in one step, the two-dimensional tip pattern comprising a plurality of super-hydrophilic regions and super-hydrophobic regions in a tip structure and distributed between each other, the tip angle θ1 of the super-hydrophilic region and the super-hydrophobic region being 15°;

[0082] The wedge structure has a plurality of heads that are unidirectionally and continuously spread towards the bottom end of the super-hydrophilic region, the cavity wedge angle θ2 of the wedge structure is 30°, the body length L2 is 400 μm, the pull-up length L3 is 400 μm, the elliptical semi-major axis length L1 is 820 μm, and the cavity length L4 is 820 μm;

[0083] The three-dimensional conical columns are several, and the several three-dimensional conical columns stand above the wedge-shaped structures, the bottom diameter R of the three-dimensional conical columns is 100 μm, the height of the three-dimensional conical columns is 200 μm, longitudinal grooves are arranged on the side surface of the three-dimensional conical columns, the number of the longitudinal grooves is 3, and the longitudinal grooves extend from the tip of the three-dimensional conical columns to the root;

[0084] The super-hydrophobic area is provided with a plurality of spaced recesses, the diameter of the recesses is 200 μm, the depth is 50 μm, and the spacing between adjacent recesses is 200 μm;

[0085] After 3D printing, the substrate is ultrasonically washed with deionized water and ethanol for 20 minutes respectively, and is naturally dried to obtain the substrate;

[0086] S2, coating: using a tip pattern consistent with the size of the super-hydrophobic area as a mask for aligning the super-hydrophobic area, spraying super-hydrophilic paint on the super-hydrophilic area of the substrate in step S1; using a tip pattern consistent with the size of the super-hydrophilic area as a mask for aligning the super-hydrophilic area, coating super-hydrophobic paint on the super-hydrophobic area of the substrate in step S1; drying in air to form a super-hydrophilic coating layer covering the surface of the wedge-shaped structure and the three-dimensional conical column, and after the super-hydrophobic coating layer covering the surface of the super-hydrophobic area, a water collecting surface is obtained.

[0087] Water collecting performance test: taking the prepared water collecting surface to test water collecting in a simulated fog wind environment, and obtaining a water collecting efficiency of 5.2 g / h / cm 2 After 20 cycles of testing, the water collecting efficiency remains at about 5.0 g / h / cm 2 .

[0088] Example 4:

[0089] A preparation method of a water collecting surface coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column, the method comprising:

[0090] S1, preparing a substrate: using a light-cured 3D printer to print a resin material to once-form a substrate coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column, the two-dimensional tip pattern comprising a plurality of super-hydrophilic areas and super-hydrophobic areas distributed in a tip structure, and the tip angle θ1 of the super-hydrophilic areas and the super-hydrophobic areas is 20°;

[0091] The wedge-shaped structures are several, and the heads of the several wedge-shaped structures are unidirectionally and continuously spread towards the bottom end of the super-hydrophilic area, the cavity wedge angle θ2 of the wedge-shaped structure is 30°, the body length L2 is 500 μm, the pull-up length L3 is 460 μm, the elliptical semi-major axis length L1 is 860 μm, and the cavity length L4 is 860 μm;

[0092] The three-dimensional conical columns are several, and the several three-dimensional conical columns stand above the wedge-shaped structures, the bottom diameter R of the three-dimensional conical columns is 100 μm, the height of the three-dimensional conical columns is 200 μm, longitudinal grooves are arranged on the side surface of the three-dimensional conical columns, the number of the longitudinal grooves is 3, and the longitudinal grooves extend from the tip of the three-dimensional conical columns to the root.

[0093] The super-hydrophobic area is provided with a plurality of spaced recesses, the diameter of the recesses is 200 μm, the depth is 50 μm, and the spacing between adjacent recesses is 200 μm.

[0094] After 3D printing, the substrate is ultrasonically washed with deionized water and ethanol for 20 minutes respectively, and is naturally dried to obtain the substrate.

[0095] S2, coating: using a tip pattern consistent with the size of the super-hydrophobic area as a mask for aligning the super-hydrophobic area, spraying super-hydrophilic paint on the super-hydrophilic area of the substrate in step S1; using a tip pattern consistent with the size of the super-hydrophilic area as a mask for aligning the super-hydrophilic area, coating super-hydrophobic paint on the super-hydrophobic area of the substrate in step S1; drying in air to form a super-hydrophilic coating layer covering the surface of the wedge-shaped structure and the three-dimensional conical column, and after the super-hydrophobic coating layer covering the surface of the super-hydrophobic area, a water collecting surface is obtained.

[0096] Water collecting performance test: taking the prepared water collecting surface to test water collecting in a simulated fog wind environment, and obtaining a water collecting efficiency of 4.8 g / h / cm 2 After 20 cycles of testing, the water collecting efficiency remains at about 4.5 g / h / cm 2 .

[0097] Example 5:

[0098] A preparation method of a water collecting surface coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column, the method comprising:

[0099] S1, preparing a substrate: using a light-cured 3D printer to print a resin material, and once-forming a substrate coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column, the two-dimensional tip pattern comprising a plurality of super-hydrophilic areas and super-hydrophobic areas distributed in a tip structure, and the tip angle θ1 of the super-hydrophilic areas and the super-hydrophobic areas is 30°;

[0100] The wedge-shaped structures are several, and the heads of the several wedge-shaped structures are unidirectionally and continuously spread towards the bottom end of the super-hydrophilic area, the cavity wedge angle θ2 of the wedge-shaped structure is 30°, the body length L2 is 500 μm, the pull-up length L3 is 460 μm, the elliptical semi-major axis length L1 is 860 μm, and the cavity length L4 is 860 μm;

[0101] The three-dimensional conical columns are several, and the several three-dimensional conical columns stand above the wedge-shaped structures, the bottom diameter R of the three-dimensional conical columns is 100 μm, the height of the three-dimensional conical columns is 200 μm, longitudinal grooves are arranged on the side surface of the three-dimensional conical columns, the number of the longitudinal grooves is 3, and the longitudinal grooves extend from the tip of the three-dimensional conical columns to the root.

[0102] The super-hydrophobic area is provided with a plurality of spaced recesses, the diameter of the recesses is 250 μm, the depth is 80 μm, and the spacing between adjacent recesses is 300 μm.

[0103] After 3D printing, the substrate is ultrasonically washed with deionized water and ethanol for 20 minutes respectively, and is naturally dried to obtain the substrate.

[0104] S2, coating: using a tip pattern consistent with the size of the super-hydrophobic area as a mask for aligning the super-hydrophobic area, spraying super-hydrophilic paint on the super-hydrophilic area of the substrate in step S1; using a tip pattern consistent with the size of the super-hydrophilic area as a mask for aligning the super-hydrophilic area, coating super-hydrophobic paint on the super-hydrophobic area of the substrate in step S1; drying in air to form a super-hydrophilic coating layer covering the surface of the wedge-shaped structure and the three-dimensional conical column, and after the super-hydrophobic coating layer covering the surface of the super-hydrophobic area, a water collecting surface is obtained.

[0105] Water collecting performance test: taking the prepared water collecting surface to perform water collecting test in a simulated fog wind environment, and obtaining a water collecting efficiency of 4.5 g / h / cm 2 After 20 cycles of test, the water collecting efficiency remains at about 4.5 g / h / cm 2 .

[0106] Comparative Example 2:

[0107] A method for preparing a water collecting surface, which is different from Example 5 in that the tip angle θ1 of the super-hydrophilic area and the super-hydrophobic area is 40°, and taking the prepared water collecting surface to perform water collecting test in a simulated fog wind environment, and obtaining a water collecting efficiency of 1.6 g / h / cm 2 After 20 cycles of test, the water collecting efficiency remains at about 1.5 g / h / cm 2 .

[0108] The comparison results of Example 5 and Comparative Example 2 show that the tip angle of the super-hydrophilic area and the super-hydrophobic area of the two-dimensional tip patterned surface is too large, which results in that the Laplace pressure generated by the geometric structure is not enough to quickly drive the directional transport of water droplets, and the water collecting efficiency is significantly reduced.

[0109] Example 6:

[0110] A method for preparing a water collecting surface coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column, which comprises:

[0111] S1, preparing a substrate: using a light-cured 3D printer to print a resin material, once-forming a substrate coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column, the two-dimensional tip pattern comprising a plurality of super-hydrophilic regions and super-hydrophobic regions distributed in a tip structure, the tip angle θ1 of the super-hydrophilic regions and super-hydrophobic regions being 15°;

[0112] The wedge-shaped structure has a plurality of wedge-shaped structures, the heads of the plurality of wedge-shaped structures are unidirectionally and continuously spread towards the bottom end of the super-hydrophilic region, the cavity wedge angle θ2 of the wedge-shaped structure is 30°, the body length L2 is 500 μm, the pull-up length L3 is 460 μm, the elliptical semi-major axis length L1 is 860 μm, and the cavity length L4 is 860 μm;

[0113] The three-dimensional conical column has a plurality of three-dimensional conical columns, and the plurality of three-dimensional conical columns respectively stand above the wedge-shaped structures, the bottom end diameter R of the three-dimensional conical column is 50 μm, the height of the three-dimensional conical column is 100 μm, the three-dimensional conical column is provided with a longitudinal groove, the number of the longitudinal groove is 3, and the longitudinal groove extends from the tip of the three-dimensional column to the root;

[0114] The super-hydrophobic region is provided with a plurality of spaced recesses, the diameter of the recess is 250 μm, the depth is 80 μm, and the distance between adjacent recesses is 300 μm;

[0115] After 3D printing, the substrate is ultrasonically washed with deionized water and ethanol for 20 minutes, and naturally dried to obtain the substrate;

[0116] S2, coating: using a tip pattern with the same size as the super-hydrophobic region as a mask for aligning the super-hydrophobic region, spraying super-hydrophilic paint on the super-hydrophilic region of the substrate in step S1; using a tip pattern with the same size as the super-hydrophilic region as a mask for aligning the super-hydrophilic region, coating super-hydrophobic paint on the super-hydrophobic region of the substrate in step S1; drying in air to form a super-hydrophilic coating layer covering the surface of the wedge-shaped structure and the three-dimensional conical column, and a super-hydrophobic coating layer covering the surface of the super-hydrophobic region, thereby obtaining a water collecting surface.

[0117] Water collecting performance test: taking the prepared water collecting surface to test water collecting in a simulated fog wind environment, and obtaining a water collecting efficiency of 4.0 g / h / cm 2 After 20 cycles of testing, the water collecting efficiency remains at about 4.0 g / h / cm 2 .

[0118] Example 7:

[0119] A method for preparing a water collecting surface coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column, the method comprising:

[0120] S1, preparing a substrate: using a light-cured 3D printer to print a resin material, once-forming a substrate of a coupling wedge structure, a two-dimensional tip pattern and a three-dimensional conical column, the two-dimensional tip pattern comprising a plurality of super-hydrophilic regions and super-hydrophobic regions in a tip structure and inter-distributed, the tip angle θ1 of the super-hydrophilic regions and the super-hydrophobic regions being 15°;

[0121] The wedge structure has a plurality of wedge structures, the heads of the plurality of wedge structures are unidirectionally and continuously spread toward the bottom end of the super-hydrophilic region, the cavity wedge angle θ2 of the wedge structure is 30°, the body length L2 is 400 μm, the pull-up length L3 is 400 μm, the elliptical semi-major axis length L1 is 820 μm, and the cavity length L4 is 820 μm;

[0122] The three-dimensional conical column has a plurality of three-dimensional conical columns, and the plurality of three-dimensional conical columns respectively stand above the wedge structures, the bottom end diameter R of the three-dimensional conical column is 150 μm, the height of the three-dimensional conical column is 200 μm, the three-dimensional conical column is provided with a longitudinal groove, the number of the longitudinal groove is 3, and the longitudinal groove extends from the tip of the three-dimensional column to the root;

[0123] The super-hydrophobic region is provided with a plurality of spaced recesses, the diameter of the recess is 250 μm, the depth is 80 μm, and the distance between adjacent recesses is 300 μm;

[0124] After 3D printing, the substrate is ultrasonically washed with deionized water and ethanol for 20 minutes, and naturally dried to obtain the substrate;

[0125] S2, coating: using a tip pattern with the same size as the super-hydrophobic region as a mask for aligning the super-hydrophobic region, spraying super-hydrophilic paint on the super-hydrophilic region of the substrate in step S1; using a tip pattern with the same size as the super-hydrophilic region as a mask for aligning the super-hydrophilic region, coating the super-hydrophobic region of the substrate in step S1 with super-hydrophobic paint; drying in air to form a super-hydrophilic coating on the surface of the wedge structure and the three-dimensional conical column, and a super-hydrophobic coating on the surface of the super-hydrophobic region, thereby obtaining a water collecting surface.

[0126] Water collecting performance test: taking the prepared water collecting surface to test the water collecting performance in a simulated fog wind environment, and obtaining a water collecting efficiency of 5.05 g / h / cm 2 After 20 cycles of testing, the water collecting efficiency remains at about 5.0 g / h / cm 2 .

[0127] Comparative Example 3:

[0128] A method for preparing a water collecting surface, which is different from Example 7 in that the bottom end diameter R of the three-dimensional conical column is 40 μm, and taking the prepared water collecting surface to test the water collecting performance in a simulated fog wind environment, and obtaining a water collecting efficiency of 1.6 g / h / cm 2After 20 cycles of testing, the water collection efficiency remained at 1.5 g / h / cm 2 left and right.

[0129] The comparison results of Example 7 and Comparative Example 3 show that the smaller diameter R of the bottom end of the three-dimensional conical column is not conducive to the aggregation of micro water droplets into larger water droplets, and the smaller structure parameters of the conical column result in incomplete conical column array due to lower equipment precision, which leads to a significant decrease in water collection efficiency.

[0130] Example 8:

[0131] A method for preparing a water collection surface coupled with a wedge structure, a two-dimensional tip pattern, and a three-dimensional conical column, the method comprising:

[0132] S1, preparing a substrate: using a light-cured 3D printer to print a resin material, a substrate coupled with a wedge structure, a two-dimensional tip pattern, and a three-dimensional conical column is prepared by one-time forming, the two-dimensional tip pattern comprises a plurality of super-hydrophilic regions and super-hydrophobic regions distributed between each other in a tip structure, and the tip angle θ1 of the super-hydrophilic regions and the super-hydrophobic regions is 15°;

[0133] The wedge structure has a plurality of heads that are unidirectionally and continuously spread toward the bottom end of the super-hydrophilic region, the cavity wedge angle θ2 of the wedge structure is 30°, the body length L2 is 400 μm, the pull-up length L3 is 400 μm, the elliptical semi-major axis length L1 is 820 μm, and the cavity length L4 is 820 μm;

[0134] The three-dimensional conical column has a plurality of three-dimensional conical columns that stand above the wedge structure, the bottom end diameter R of the three-dimensional conical column is 500 μm, the height of the three-dimensional conical column is 800 μm, the three-dimensional conical column side is provided with a longitudinal groove, the number of the longitudinal groove is 3, and the longitudinal groove extends from the tip of the three-dimensional column to the root;

[0135] The super-hydrophobic region is provided with a plurality of spaced recesses, the diameter of the recess is 250 μm, the depth is 80 μm, and the distance between adjacent recesses is 300 μm;

[0136] After 3D printing, the substrate is ultrasonically rinsed with deionized water and ethanol for 20 minutes, and naturally dried to obtain the substrate;

[0137] S2, coating: using a tip pattern with the same size as the super-hydrophobic region as a mask for aligning the super-hydrophobic region, spraying super-hydrophilic paint on the super-hydrophilic region of the substrate in step S1; using a tip pattern with the same size as the super-hydrophilic region as a mask for aligning the super-hydrophilic region, coating the super-hydrophobic region of the substrate in step S1 with super-hydrophobic paint; drying in air to form a super-hydrophilic coating on the surface of the wedge structure and the three-dimensional conical column, and after the super-hydrophobic coating on the surface of the super-hydrophobic region, a water collection surface is obtained.

[0138] Water collection performance test: take the prepared water collection surface in the simulated fog wind environment to carry out water collection test, and obtain the water collection efficiency of 4.7 g / h / cm 2 After 20 cycles of test, the water collection efficiency remains at about 4.7 g / h / cm 2 .

[0139] Example 9

[0140] A method for preparing a water collection surface coupled with wedge-shaped structure, two-dimensional tip pattern and three-dimensional conical column, the method comprising:

[0141] S1, preparing a substrate: printing a resin material by using a photocuring 3D printer to prepare a substrate coupled with wedge-shaped structure, two-dimensional tip pattern and three-dimensional conical column in one step, the two-dimensional tip pattern comprising a plurality of super-hydrophilic regions and super-hydrophobic regions distributed in a tip structure, and the tip angle θ1 of the super-hydrophilic regions and super-hydrophobic regions being 15°;

[0142] The wedge-shaped structure has a plurality of wedge-shaped structures, and the heads of the plurality of wedge-shaped structures are unidirectionally and continuously spread towards the bottom end of the super-hydrophilic region, the cavity wedge angle θ2 of the wedge-shaped structure being 30°, the body length L2 being 400 μm, the pull-up length L3 being 820 μm, the elliptical semi-major axis length L1 being 400 μm, and the cavity length L4 being 820 μm;

[0143] The three-dimensional conical column has a plurality of three-dimensional conical columns, and the plurality of three-dimensional conical columns respectively stand above the wedge-shaped structures, the bottom end diameter R of the three-dimensional conical column being 200 μm, the height of the three-dimensional conical column being 400 μm, the three-dimensional conical column side being provided with longitudinal grooves, the number of the longitudinal grooves being 3, and the longitudinal grooves extending from the three-dimensional columnar column tip to the root;

[0144] The super-hydrophobic region is provided with a plurality of spaced recesses, the diameter of the recess being 200 μm, the depth being 50 μm, and the spacing between adjacent recesses being 200 μm;

[0145] After 3D printing, the substrate is ultrasonically rinsed with deionized water and ethanol for 20 min respectively, and is naturally dried to obtain the substrate;

[0146] S2, coating: using a tip pattern with the same size as the super-hydrophobic region as a mask for aligning the super-hydrophobic region, spraying super-hydrophilic paint on the super-hydrophilic region of the substrate in step S1; using a tip pattern with the same size as the super-hydrophilic region as a mask for aligning the super-hydrophilic region, coating super-hydrophobic paint on the super-hydrophobic region of the substrate in step S1; drying in air to form a super-hydrophilic coating layer covering the surface of the wedge-shaped structure and the three-dimensional conical column, and after the super-hydrophobic coating layer covering the surface of the super-hydrophobic region, a water collection surface is obtained.

[0147] Water collection performance test: take the prepared water collection surface in the simulated fog wind environment to carry out water collection test, and obtain the water collection efficiency of 5.75 g / h / cm2 After 20 cycles of testing, the water collection efficiency remained at about 5.6 g / h / cm 2 .

[0148] Comparative Example 4:

[0149] A method for preparing a water collection surface, which is different from Example 9 in that the bottom end diameter R of the three-dimensional conical column is 600 μm, and the prepared water collection surface is subjected to water collection testing in a simulated fog environment, obtaining a water collection efficiency of 2.6 g / h / cm 2 After 20 cycles of testing, the water collection efficiency remained at about 2.5 g / h / cm 2 .

[0150] The comparative results of Example 9 and Comparative Example 4 show that a larger bottom end diameter R of the three-dimensional conical column is not conducive to the adsorption, aggregation and directional transport of micro water droplets, and a larger conical column structure parameter results in a smaller number of conical columns per unit area, and the water collection efficiency is significantly reduced.

[0151] Example 10:

[0152] A method for preparing a water collection surface coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column, the method comprising:

[0153] S1, preparing a substrate: using a light-cured 3D printer to print a resin material, a substrate coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column is prepared by one-step forming, the two-dimensional tip pattern comprises a plurality of super-hydrophilic regions and super-hydrophobic regions distributed between each other in a tip structure, and the tip angle θ1 of the super-hydrophilic regions and the super-hydrophobic regions is 5°-30°;

[0154] The wedge-shaped structure has a plurality of wedge-shaped structures, the heads of the plurality of wedge-shaped structures are unidirectionally and continuously spread toward the bottom end of the super-hydrophilic region, the cavity wedge angle θ2 of the wedge-shaped structure is 30°, the body length L2 is 350 μm, the pull-up length L3 is 400 μm, the elliptical semi-major axis length L1 is 650 μm, and the cavity length L4 is 700 μm;

[0155] The three-dimensional conical column has a plurality of three-dimensional conical columns, and the plurality of three-dimensional conical columns respectively stand above the wedge-shaped structures, the bottom end diameter R of the three-dimensional conical column is 200 μm, the height of the three-dimensional conical column is 400 μm, the three-dimensional conical column side is provided with a longitudinal groove, the number of the longitudinal groove is 2, and the longitudinal groove extends from the tip of the three-dimensional conical column to the root;

[0156] The super-hydrophobic region is provided with a plurality of spaced recesses, the diameter of the recess is 200 μm, the depth is 50 μm, and the distance between adjacent recesses is 200 μm;

[0157] 3D printing after using deionized water and ethanol respectively ultrasonic flushing the substrate 20 min, natural drying to obtain the substrate;

[0158] S2, coating: using the tip pattern consistent with the size of the super-hydrophobic area as a mask to align the super-hydrophobic area, spraying super-hydrophilic paint on the super-hydrophilic area of the substrate in step S1; using the tip pattern consistent with the size of the super-hydrophilic area as a mask to align the super-hydrophilic area, coating super-hydrophobic paint on the super-hydrophobic area of the substrate in step S1; drying in air to form a super-hydrophilic coating on the surface of the wedge structure and the three-dimensional conical column, and after the super-hydrophobic coating on the surface of the super-hydrophobic area, a water collecting surface is obtained.

[0159] Water collecting performance test: taking the prepared water collecting surface to test water collecting in a simulated fog wind environment, and obtaining a water collecting efficiency of 4.9 g / h / cm 2 After 20 cycles of testing, the water collecting efficiency remains at about 4.7 g / h / cm 2 .

[0160] Comparative Example 5:

[0161] A method for preparing a water collecting surface, which is different from Example 10 in that the number of longitudinal grooves is 1, and taking the prepared water collecting surface to test water collecting in a simulated fog wind environment, and obtaining a water collecting efficiency of 3.1 g / h / cm 2 After 20 cycles of testing, the water collecting efficiency remains at about 3.0 g / h / cm 2 .

[0162] The comparison results of Example 10 and Comparative Example 5 show that the number of longitudinal grooves on the side surface of the three-dimensional conical column is small, and the capillary force of a single longitudinal groove is insufficient to adsorb, gather and directionally transport a large number of water droplets, resulting in a decrease in water collecting efficiency.

[0163] Example 11:

[0164] A method for preparing a water collecting surface coupled with a wedge structure, a two-dimensional tip pattern and a three-dimensional conical column, which comprises:

[0165] S1, preparing a substrate: using a light-cured 3D printer to print a resin material to prepare a substrate coupled with a wedge structure, a two-dimensional tip pattern and a three-dimensional conical column in one step, the two-dimensional tip pattern comprising a plurality of super-hydrophilic areas and super-hydrophobic areas in a tip structure and distributed between each other, and the tip angle θ1 of the super-hydrophilic areas and the super-hydrophobic areas being 15°;

[0166] The wedge structure has a plurality of heads, and the heads of the plurality of wedge structures are unidirectionally and continuously spread towards the bottom end of the super-hydrophilic area, the cavity wedge angle θ2 of the wedge structure is 30°, the body length L2 is 350 μm, the pull-up length L3 is 400 μm, the elliptical semi-major axis length L1 is 650 μm, and the cavity length L4 is 700 μm.

[0167] The three-dimensional conical columns are several, and the several three-dimensional conical columns stand above the wedge structures. The bottom end diameter R of the three-dimensional conical column is 200 μm, the height of the three-dimensional conical column is 400 μm, and a longitudinal groove is arranged on the side of the three-dimensional conical column. The number of the longitudinal grooves is 4, and the longitudinal grooves extend from the tip of the three-dimensional column to the root.

[0168] The super-hydrophobic area is provided with a plurality of spaced recesses. The diameter of the recess is 200 μm, the depth is 50 μm, and the spacing between adjacent recesses is 200 μm.

[0169] After 3D printing, the substrate is ultrasonically rinsed with deionized water and ethanol for 20 minutes, and then naturally dried to obtain the substrate.

[0170] S2, coating: using a tip pattern consistent with the size of the super-hydrophobic area as a mask for aligning the super-hydrophobic area, spraying super-hydrophilic paint on the super-hydrophilic area of the substrate in step S1; using a tip pattern consistent with the size of the super-hydrophilic area as a mask for aligning the super-hydrophilic area, coating super-hydrophobic paint on the super-hydrophobic area of the substrate in step S1; drying in air to form a super-hydrophilic coating on the surface of the wedge structure and the three-dimensional conical column, and then obtaining a water collecting surface.

[0171] Water collecting performance test: taking the prepared water collecting surface to test the water collecting performance in a simulated fog environment, and obtaining a water collecting efficiency of 6.5 g / h / cm 2 After 20 cycles of testing, the water collecting efficiency remains at about 6.5 g / h / cm 2 .

[0172] Example 12:

[0173] A method for preparing a water collecting surface coupled with a wedge structure, a two-dimensional tip pattern and a three-dimensional conical column, the method comprising:

[0174] S1, preparing a substrate: using a light-cured 3D printer to print a resin material to prepare a substrate coupled with a wedge structure, a two-dimensional tip pattern and a three-dimensional conical column in one step. The two-dimensional tip pattern comprises a plurality of super-hydrophilic areas and super-hydrophobic areas arranged in a tip structure and alternating with each other. The tip angle θ1 of the super-hydrophilic area and the super-hydrophobic area is 15°.

[0175] The wedge structures are several, and the heads of the several wedge structures are unidirectionally and continuously spread towards the bottom end of the super-hydrophilic area. The cavity wedge angle θ2 of the wedge structure is 30°, the body length L2 is 400 μm, the pull-up length L3 is 400 μm, the elliptical semi-major axis length L1 is 820 μm, and the cavity length L4 is 820 μm.

[0176] The three-dimensional conical columns are several, and the several three-dimensional conical columns stand above the wedge-shaped structures, the bottom diameter R of the three-dimensional conical columns is 200 μm, the height of the three-dimensional conical columns is 400 μm, longitudinal grooves are arranged on the side surface of the three-dimensional conical columns, the number of the longitudinal grooves is 6, and the longitudinal grooves extend from the tip of the three-dimensional conical columns to the root.

[0177] The super-hydrophobic area is provided with a plurality of spaced recesses, the diameter of the recesses is 250 μm, the depth is 80 μm, and the spacing between adjacent recesses is 300 μm.

[0178] After 3D printing, the substrate is ultrasonically washed with deionized water and ethanol for 20 minutes respectively, and is naturally dried to obtain the substrate.

[0179] S2, coating: using a tip pattern consistent with the size of the super-hydrophobic area as a mask for aligning the super-hydrophobic area, spraying super-hydrophilic paint on the super-hydrophilic area of the substrate in step S1; using a tip pattern consistent with the size of the super-hydrophilic area as a mask for aligning the super-hydrophilic area, coating super-hydrophobic paint on the super-hydrophobic area of the substrate in step S1; drying in air to form a super-hydrophilic coating layer covering the surface of the wedge-shaped structure and the three-dimensional conical column, and after the super-hydrophobic coating layer covering the surface of the super-hydrophobic area, a water collecting surface is obtained.

[0180] Water collecting performance test: taking the prepared water collecting surface to test water collecting in a simulated fog environment, and obtaining a water collecting efficiency of 7.5 g / h / cm 2 After 20 cycles of testing, the water collecting efficiency remains at about 7.3 g / h / cm 2 .

[0181] Example 13:

[0182] A preparation method of a water collecting surface coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column, the method comprising:

[0183] S1, preparing a substrate: using a light-cured 3D printer to print a resin material, and once-forming a substrate coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column, the two-dimensional tip pattern comprising a plurality of super-hydrophilic areas and super-hydrophobic areas distributed in a tip structure, and the tip angle θ1 of the super-hydrophilic areas and the super-hydrophobic areas is 15°;

[0184] The wedge-shaped structures are several, and the heads of the several wedge-shaped structures are unidirectionally and continuously spread towards the bottom end of the super-hydrophilic area, the cavity wedge angle θ2 of the wedge-shaped structure is 30°, the body length L2 is 400 μm, the pull-up length L3 is 400 μm, the elliptical semi-major axis length L1 is 820 μm, and the cavity length L4 is 820 μm;

[0185] The plurality of three-dimensional conical columns are respectively erected above the wedge-shaped structures, the bottom end diameter R of the three-dimensional conical column is 200 μm, the height of the three-dimensional conical column is 400 μm, and a longitudinal groove is arranged on the side surface of the three-dimensional conical column, the number of the longitudinal grooves is 8, and the longitudinal grooves extend from the tip of the three-dimensional column to the root.

[0186] The super-hydrophobic region is provided with a plurality of spaced recesses, the diameter of the recess is 250 μm, the depth is 80 μm, and the spacing between adjacent recesses is 300 μm.

[0187] After 3D printing, the substrate is ultrasonically washed with deionized water and ethanol for 20 minutes respectively, and then naturally dried to obtain the substrate.

[0188] S2, coating: using a tip pattern consistent with the size of the super-hydrophobic region as a mask for aligning the super-hydrophobic region, spraying super-hydrophilic paint on the super-hydrophilic region of the substrate in step S1; using a tip pattern consistent with the size of the super-hydrophilic region as a mask for aligning the super-hydrophilic region, coating super-hydrophobic paint on the super-hydrophobic region of the substrate in step S1; drying in air to form a super-hydrophilic coating layer covering the surface of the wedge-shaped structure and the three-dimensional conical column, and then obtaining a water collecting surface.

[0189] Water collecting performance test: taking the prepared water collecting surface to test the water collecting performance in a simulated fog wind environment, and obtaining a water collecting efficiency of 6.2 g / h / cm 2 After 20 cycles of testing, the water collecting efficiency remains at about 6.0 g / h / cm 2 .

[0190] Comparative Example 6:

[0191] A method for preparing a water collecting surface, which is different from Example 13 in that the number of longitudinal grooves is 12, and taking the prepared water collecting surface to test the water collecting performance in a simulated fog wind environment, and obtaining a water collecting efficiency of 2.7 g / h / cm 2 After 20 cycles of testing, the water collecting efficiency remains at about 2.5 g / h / cm 2 .

[0192] The comparison results of Example 13 and Comparative Example 6 show that the number of longitudinal grooves on the side surface of the three-dimensional conical column is larger, and the longitudinal grooves generate stronger capillary force, which makes the water droplets adhere tightly to the three-dimensional conical column, hinders the directional transport of water droplets from the conical column to the wedge-shaped structure, and causes the water collecting efficiency to decrease significantly.

[0193] Example 14:

[0194] A method for preparing a water collecting surface coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column, the method comprising:

[0195] S1, preparing a substrate: using a light-cured 3D printer to print a resin material, once-forming to prepare a substrate coupled with a wedge-shaped structure, a two-dimensional tip pattern and a three-dimensional conical column, the two-dimensional tip pattern comprising a plurality of super-hydrophilic regions and super-hydrophobic regions distributed in a tip structure, and the tip angle θ1 of the super-hydrophilic regions and super-hydrophobic regions is 15°;

[0196] The wedge-shaped structure has a plurality of wedge-shaped structures, the heads of the plurality of wedge-shaped structures are unidirectionally and continuously spread toward the bottom end of the super-hydrophilic region, the cavity wedge angle θ2 of the wedge-shaped structure is 30°, the body length L2 is 400 μm, the pull-up length L3 is 400 μm, the elliptical semi-major axis length L1 is 820 μm, and the cavity length L4 is 820 μm;

[0197] The three-dimensional conical column has a plurality of three-dimensional conical columns, and the plurality of three-dimensional conical columns respectively stand above the wedge-shaped structures, the bottom end diameter R of the three-dimensional conical column is 100 μm, the height of the three-dimensional conical column is 80 μm, the three-dimensional conical column is provided with a longitudinal groove, the number of the longitudinal groove is 6, and the longitudinal groove extends from the tip of the three-dimensional column to the root;

[0198] The super-hydrophobic region is provided with a plurality of spaced recesses, the diameter of the recess is 250 μm, the depth is 80 μm, and the distance between adjacent recesses is 300 μm;

[0199] After 3D printing, the substrate is ultrasonically washed with deionized water and ethanol for 20 minutes, and naturally dried to obtain the substrate;

[0200] S2, coating: using a tip pattern with the same size as the super-hydrophobic region as a mask for aligning the super-hydrophobic region, spraying super-hydrophilic paint on the super-hydrophilic region of the substrate in step S1; using a tip pattern with the same size as the super-hydrophilic region as a mask for aligning the super-hydrophilic region, coating the super-hydrophobic region of the substrate in step S1 with super-hydrophobic paint; drying in air to form a super-hydrophilic coating on the surface of the wedge-shaped structure and the three-dimensional conical column, and a super-hydrophobic coating on the surface of the super-hydrophobic region, thereby obtaining a water collecting surface.

[0201] Water collecting performance test: taking the prepared water collecting surface to test the water collecting performance in a simulated fog wind environment, and obtaining a water collecting efficiency of 4.5 g / h / cm 2 After 20 cycles of testing, the water collecting efficiency remains at about 4.4 g / h / cm 2

[0202] Comparative Example 7:

[0203] A method for preparing a water collecting surface, which is different from Example 14 in that the height of the three-dimensional conical column is 60 μm, and taking the prepared water collecting surface to test the water collecting performance in a simulated fog wind environment, and obtaining a water collecting efficiency of 2.5 g / h / cm 2 ​The water collection efficiency is maintained at 2.5 g / h / cm after 20 cycles 2 left and right.

[0204] The comparison results of Example 14 and Comparative Example 7 show that the height of the three-dimensional conical column is too low, and the three-dimensional conical column is not sufficient to provide a sufficient path for the large amount of adsorption, aggregation and directional transport of water droplets, resulting in a significant decrease in water collection efficiency.

[0205] Example 15:

[0206] A method for preparing a water collection surface coupled with a wedge structure, a two-dimensional tip pattern and a three-dimensional conical column, the method comprising:

[0207] S1, preparing a substrate: using a light-cured 3D printer to print a resin material, a substrate coupled with a wedge structure, a two-dimensional tip pattern and a three-dimensional conical column is prepared by one-step forming, the two-dimensional tip pattern comprises a plurality of super-hydrophilic regions and super-hydrophobic regions distributed between each other in a tip structure, and the tip angle θ1 of the super-hydrophilic regions and the super-hydrophobic regions is 15°;

[0208] The wedge structure has a plurality of wedge structures, the heads of the plurality of wedge structures are unidirectionally and continuously spread towards the bottom end of the super-hydrophilic region, the cavity wedge angle θ2 of the wedge structure is 30°, the body length L2 is 400 μm, the pull-up length L3 is 400 μm, the elliptical semi-major axis length L1 is 820 μm, and the cavity length L4 is 820 μm;

[0209] The three-dimensional conical column has a plurality of three-dimensional conical columns, and the plurality of three-dimensional conical columns respectively stand above the wedge structures, the bottom end diameter R of the three-dimensional conical column is 500 μm, the height of the three-dimensional conical column is 1400 μm, the three-dimensional conical column side is provided with longitudinal grooves, the number of the longitudinal grooves is 6, and the longitudinal grooves extend from the tip of the three-dimensional conical column to the root;

[0210] The super-hydrophobic region is provided with a plurality of spaced recesses, the diameter of the recess is 250 μm, the depth is 80 μm, and the distance between adjacent recesses is 300 μm;

[0211] After 3D printing, the substrate is ultrasonically washed with deionized water and ethanol for 20 minutes respectively, and naturally dried to obtain the substrate;

[0212] S2, coating: using a tip pattern with the same size as the super-hydrophobic region as a mask for aligning the super-hydrophobic region, spraying super-hydrophilic paint on the super-hydrophilic region of the substrate in step S1; using a tip pattern with the same size as the super-hydrophilic region as a mask for aligning the super-hydrophilic region, coating the super-hydrophobic region of the substrate in step S1 with super-hydrophobic paint; drying in air to form a super-hydrophilic coating layer on the surface of the wedge structure and the three-dimensional conical column, and after the super-hydrophobic coating layer on the surface of the super-hydrophobic region, a water collection surface is obtained.

[0213] Water harvesting performance test: The prepared water harvesting surface was taken to conduct water harvesting test in the simulated mist wind environment, and the water harvesting efficiency was 5.8 g / h / cm 2 After 20 cycles of test, the water harvesting efficiency remained at about 5.7 g / h / cm 2 .

[0214] Comparative Example 8:

[0215] A method for preparing a water harvesting surface, which is different from Example 15 in that the height of the three-dimensional conical column is 1800 μm, and the prepared water harvesting surface is taken to conduct water harvesting test in the simulated mist wind environment, and the water harvesting efficiency is 1.9 g / h / cm 2 After 20 cycles of test, the water harvesting efficiency remained at about 1.8 g / h / cm 2 .

[0216] The comparison results of Example 15 and Comparative Example 8 show that the height of the three-dimensional conical column is too high, although it can provide sufficient paths for a large number of adsorption, aggregation and directional transport of water droplets, however, the long-distance directional transport also increases the loss of water droplets through evaporation, resulting in a significant decrease in water harvesting rate.

[0217] Comparative Example 9:

[0218] A method for preparing a water harvesting surface, which is different from Example 15 in that the base is coupled with a wedge-shaped structure and a two-dimensional tip pattern, and lacks a three-dimensional conical column, and the prepared water harvesting surface is taken to conduct water harvesting test in the simulated mist wind environment, and the water harvesting efficiency is 2.6 g / h / cm 2 After 20 cycles of test, the water harvesting efficiency remained at about 2.5 g / h / cm 2 .

[0219] The comparison results of Example 15 and Comparative Example 9 show that due to the lack of three-dimensional conical columns, the entire water harvesting surface is difficult to adsorb, aggregate and directionally transport water droplets, and the water droplets have adhesion problems, resulting in a significant decrease in water harvesting rate.

[0220] Comparative Example 10:

[0221] A method for preparing a water harvesting surface, which is different from Example 15 in that the base is coupled with a three-dimensional conical column and a two-dimensional tip pattern, and lacks a wedge-shaped structure, and the prepared water harvesting surface is taken to conduct water harvesting test in the simulated mist wind environment, and the water harvesting efficiency is 2.9 g / h / cm 2 After 20 cycles of test, the water harvesting efficiency remained at about 2.9 g / h / cm 2 .

[0222] The comparison results of Example 15 and Comparative Example 10 show that, due to the lack of wedge-shaped structures, the water collection surface is difficult to direct the collected water droplets, which destroys the water collection cycle and leads to a significant decrease in the water collection rate.

[0223] Comparative Example 11:

[0224] A method for preparing a water collection surface, which is different from Example 15 in that step S2 is not processed, and the prepared water collection surface is used as a water collection test in a simulated mist wind environment, and the water collection efficiency is 2.6 g / h / cm 2 After 20 cycles of testing, the water collection efficiency remains at about 2.5 g / h / cm 2 .

[0225] The comparison results of Example 15 and Comparative Example 11 show that, due to the lack of super-hydrophilic coating and super-hydrophobic coating modification, water droplets on the two-dimensional tip patterned surface are difficult to be transported from the super-hydrophobic area to the super-hydrophilic area, and the water droplets on the wedge-shaped structure are difficult to be transported, which destroys the water collection cycle and leads to a significant decrease in the water collection rate.

[0226] Comparative Example 12:

[0227] A method for preparing a water collection surface, which is different from Example 15 in that step S2 is not sprayed with super-hydrophilic coating, and the prepared water collection surface is used as a water collection test in a simulated mist wind environment, and the water collection efficiency is 3.1 g / h / cm 2 After 20 cycles of testing, the water collection efficiency remains at about 3.0 g / h / cm 2 .

[0228] The comparison results of Example 15 and Comparative Example 12 show that, due to the lack of super-hydrophilic coating modification, water droplets on the wedge-shaped structure are difficult to be transported, which destroys the water collection cycle and leads to a decrease in the water collection rate.

[0229] Comparative Example 13:

[0230] A method for preparing a water collection surface, which is different from Example 15 in that step S2 is not coated with super-hydrophobic coating, and the prepared water collection surface is used as a water collection test in a simulated mist wind environment, and the water collection efficiency is 2.9 g / h / cm 2 After 20 cycles of testing, the water collection efficiency remains at about 2.7 g / h / cm 2 .

[0231] The comparison results of Example 15 and Comparative Example 13 show that, due to the lack of super-hydrophobic coating modification, water droplets on the two-dimensional tip patterned surface are difficult to be transported from the super-hydrophobic area to the super-hydrophilic area, which destroys the water collection cycle and leads to a decrease in the water collection rate.

[0232] The above detailed description is merely exemplary in nature and is not intended to limit the present application or the application and uses of it. Various changes to the details can be made in the application without departing from the spirit or scope of the application.

Claims

1. A water harvesting surface coupling a wedge-shaped structure, a two-dimensional tip pattern, and a three-dimensional conical pillar, characterized in that, The application relates to a two-dimensional tip patterned surface comprising a plurality of super-hydrophilic regions and super-hydrophobic regions in tip structure and inter-distributed, the super-hydrophilic regions being provided with a plurality of wedge structures and standing three-dimensional conical columns, the heads of the plurality of wedge structures being unidirectionally and continuously spread towards the bottom ends of the super-hydrophilic regions, the three-dimensional conical columns being provided with longitudinal grooves on the side surfaces, the surfaces of the wedge structures and the three-dimensional conical columns being covered with super-hydrophilic coating, and the surfaces of the super-hydrophobic regions being covered with super-hydrophobic coating; the tip angles of the super-hydrophilic regions and the super-hydrophobic regions are 5-30 DEG, the bottom end diameters of the three-dimensional conical columns are 50-500 mu m, the heights of the three-dimensional conical columns are 80-1400 mu m, and the number of the longitudinal grooves is 2-8.

2. The water harvesting surface of claim 1, wherein, The cavity wedge angle of the wedge structure is 30-65 DEG, the body length is 300-720 mu m, the pull-up length is 360-650 mu m, the elliptical semi-major axis length is 500-900 mu m, and the cavity length is 650-900 mu m.

3. The water harvesting surface of claim 1, wherein, The tip of the super-hydrophilic region is adjacent to the bottom end of the super-hydrophobic region, the bottom end of the super-hydrophilic region is adjacent to the tip of the super-hydrophobic region, and the super-hydrophobic region is provided with a plurality of interval arranged pits.

4. The water harvesting surface of claim 1, wherein, The super-hydrophilic coating is prepared by cross-linking polyvinyl alcohol and tannic acid.

5. The water harvesting surface of claim 1, wherein, The super-hydrophobic coating comprises fluorinated SiO2 nanoparticles modified by tetraethoxysilane and H,1H,2H,2H-perfluorodecyltriethoxysilane.

6. A method of fabricating a water harvesting surface that couples a wedge-shaped structure, a two-dimensional tip pattern, and a three-dimensional conical pillar, the method comprising: The method comprises the following steps: Preparation of a substrate: a 3D printed substrate coupled with wedge structures, a two-dimensional tip pattern and three-dimensional conical columns, the two-dimensional tip pattern comprising a plurality of super-hydrophilic regions and super-hydrophobic regions in tip structure and inter-distributed, the wedge structures being a plurality of wedge structures, the heads of the plurality of wedge structures being unidirectionally and continuously spread towards the bottom ends of the super-hydrophilic regions, the three-dimensional conical columns being a plurality of three-dimensional conical columns and standing in the super-hydrophilic regions, and the three-dimensional conical columns being provided with a plurality of longitudinal grooves on the side surfaces; the tip angles of the super-hydrophilic regions and the super-hydrophobic regions are 5-30 DEG, the bottom end diameters of the three-dimensional conical columns are 50-500 mu m, the heights of the three-dimensional conical columns are 80-1400 mu m, and the number of the longitudinal grooves is 2-8. Coating: super-hydrophilic paint is coated on the super-hydrophilic regions of the substrate; super-hydrophobic paint is coated on the super-hydrophobic regions of the substrate; a super-hydrophilic coating is formed on the surfaces of the wedge structures and the three-dimensional conical columns, and after the super-hydrophobic coating is formed on the surface of the super-hydrophobic regions, a water collecting surface is obtained.

7. The method of claim 6, wherein the coupling of the wedge-shaped structure, the two- dimensional tip pattern, and the three-dimensional conical pillar of the water harvesting surface is performed by, When the super-hydrophilic paint is coated, a tip pattern with the same size as the super-hydrophobic region is used as a mask for aligning the super-hydrophobic region; when the super-hydrophobic paint is coated, a tip pattern with the same size as the super-hydrophilic region is used as a mask for aligning the super-hydrophilic region.

8. The method of claim 6, wherein the coupling of the wedge-shaped structure, the two- dimensional tip pattern, and the three-dimensional conical pillar of the water harvesting surface is performed by, The method comprises the following steps: Preparation of super-hydrophilic coating: polyvinyl alcohol and tannic acid are dissolved in a solvent to obtain a mixed solution A, the mass fraction of polyvinyl alcohol in the mixed solution A is 1%-10%, the mass fraction of tannic acid in the mixed solution A is 1%-10%, the mixed solution A is fully stirred at 70-90 o C to obtain a PVA-TA hydrogel coating as a super-hydrophilic coating; Spraying super-hydrophilic paint on the super-hydrophilic regions of the substrate to form a super-hydrophilic coating after drying.

9. The method of claim 6, wherein the coupling of the wedge-shaped structure, the two- dimensional tip pattern, and the three-dimensional conical pillar of the water harvesting surface is performed by, The method comprises the following steps: Preparation of the super-hydrophobic coating: uniformly disperse SiO2 nanoparticles in a solvent and adjust pH to obtain a mixed solution B, the mass fraction of SiO2 nanoparticles in the mixed solution B is 10%-25%, add tetraethoxysilane and H,1H,2H,2H-perfluorodecyltriethoxysilane into the mixed solution B to obtain a mixed solution C, the volume fraction of the tetraethoxysilane in the mixed solution C is 2%-6%, the volume fraction of the H,1H,2H,2H-perfluorodecyltriethoxysilane in the mixed solution C is 1%-4%, and sufficiently stir the mixed solution C to obtain a fluorinated SiO2 nanoparticle suspension as the super-hydrophobic coating; coat the super-hydrophobic coating on the super-hydrophobic area of the substrate and dry to form a super-hydrophobic coating layer.

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