High-efficiency mist collector and its manufacturing method

Abstract

To provide a highly efficient mist collector improved in mist collection performance and water transportation performance, and a method for manufacturing the same.SOLUTION: This highly efficient mist collector comprises a radiation fin 1. A transportation recessed groove 2 is installed on one surface of the radiation fin. The radiation fin includes mist collection structure units 11. The mist collection structure units are connected to each other in an arc transition form by a connection arc 12. Each mist collection structure unit includes a sharp protrusion 111 and a trapezoidal connection part 112. A plurality of sharp protrusions is symmetrically arranged at equal intervals on both sides of the trapezoidal connection part. Each sharp protrusion is hydrophobic at the tip and hydrophilic at the tail edge, and an included angle between the sharp protrusion and the transportation recessed groove is 30-90°. The manufacturing method comprises: a step of spin-coating a copper plate surface with a PDMS graphene suspension and curing it to provide a copper-graphene PDMS composite layer; a step of providing a radiation fin having a sharp protrusion and a transportation recessed groove through cutting and washing; and a step of executing a hydrophobic treatment and a hydrophilic treatment.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a mist collector and a manufacturing method thereof, and more particularly to a high-efficiency mist collector and a manufacturing method thereof. [Background technology]

[0002] Freshwater is essential for the survival of all living things on Earth, but rapid population growth and pollution of water bodies are increasing the demand for clean water resources. Therefore, developing direct and efficient methods of water collection is the most direct way to solve this crisis.

[0003] Fog is a widespread resource on Earth, and mist in the air can condense and become a freshwater resource directly accessible to humans. By studying the efficient mist collection capabilities of animal and plant structural surfaces, scientists have been inspired to develop artificial bionic mist collectors. Existing methods for fabricating mist collection devices include kirigami cutting, electrospinning, and 3D printing. However, mist collectors fabricated using these techniques focus solely on improving a single performance and rarely explore the impact of thermodynamic heat absorption and dissipation during the mist collection process on mist collection efficiency. As a result, their mist collection capabilities are extremely limited. An ideal mist collector would be able to quickly capture mist droplets and achieve ultrafast water transport, while also providing an excellent thermal management interface to promote mist droplet condensation. Existing two-dimensional mist collectors have low water collection efficiency, slow transport speeds, and are prone to droplet clogging. Therefore, further improvements in heat dissipation and condensation efficiency are needed. Summary of the Invention [Problem to be solved by the invention]

[0004] Regarding the purpose of the invention, in order to eliminate the deficiencies in the prior art, the purpose of the present invention is to provide a high-efficiency mist collector that has high mist collection efficiency, quickly transports water, and accelerates condensation. Another purpose of the present invention is to provide a method for manufacturing a high-efficiency mist collector that has high processing accuracy, low processing cost, and excellent wetting performance. [Means for solving the problem]

[0005] Regarding technical solutions, the high-efficiency mist collector of the present invention comprises: To release the latent heat generated when mist condenses The heat dissipating fin (1) has a conveying groove (2) on one surface thereof, and the heat dissipating fin (1) has a plurality of mist collecting structural units (11) between which the mist collecting structural units (11) are spaced. , reducing the resistance of the droplets being transported The connecting arc (12) Mutually The mist collecting structure unit (11) is connected to the conveying groove (2), and the mist collecting structure unit (11) includes a sharp protrusion (111) and a trapezoidal connecting portion (112), and a plurality of sharp protrusions (111) are symmetrically installed on both sides of the trapezoidal connecting portion (112) at equal intervals, and the tip of the sharp protrusion (111) is hydrophobic and the tail end is hydrophilic, and the included angle between the sharp protrusion (111) and the conveying groove (2) is 30 to 90 degrees.

[0006] Furthermore, the heat dissipation fins are made of graphene Composite material in which is dispersed in polydimethylsiloxane (PDMS) and a copper plate layer having a transport groove (2) at the center.

[0007] Furthermore, the length of the sharp protrusions is 0.5 to 1.1 mm, and the included angle is 10 to 23°. The wetting performance of the sharp protrusions is superhydrophobic, superhydrophobic-superhydrophilic, or superhydrophilic. Preferably, the length of the sharp protrusions is 0.7 mm, the included angle is 12°, and the included angle between the sharp protrusions and the transport groove is 60°.

[0008] Furthermore, both the trapezoidal connecting portions and the connecting arcs are hydrophilic.

[0009] Furthermore, the radius of the connecting arc is 1.0 to 1.4 mm and the arc length is 0.6 to 1.0 mm. Preferably, the radius of the connecting arc is 1.2 mm and the arc length is 0.8 mm.

[0010] Furthermore, the trapezoidal connecting portion has an upper base of 0.3 to 0.4 mm, a lower base of 0.7 to 0.9 mm, and a height of 2 to 2.5 mm. Preferably, the trapezoidal connecting portion has an upper base of 0.35 mm, a lower base of 0.8 mm, and a height of 2.2 mm.

[0011] The method for manufacturing a high-efficiency mist collector according to the present invention includes: Step 1: spin-coating the PDMS-graphene suspension onto a copper plate surface and curing it to obtain a copper-graphene PDMS composite layer; Step 2: laser cutting the copper-graphene PDMS composite layer into a predetermined shape and cleaning it to obtain heat dissipation fins with transport grooves on the surface; and step 3 of subjecting the tips of the sharp protrusions to hydrophobic treatment, and subjecting the tails of the sharp protrusions, the trapezoidal connecting portions, and the connecting arcs to hydrophilic treatment.

[0012] Furthermore, in step 1, the PDMS graphene suspension is Polydimethylsiloxane (hereinafter referred to as " PDMS ") The PDMS, crosslinker, and graphene powder are mixed in a mass ratio of 10:1:0.2-0.5, and the curing temperature is set to 60-80°C for 4-6 hours. Preferably, the mass ratio of PDMS, crosslinker, and graphene powder is 10:1:0.5. The crosslinker is either dibutyl phthalate or dibutyltin dilaurate.

[0013] Furthermore, in step 2, the central wavelength of the laser pulse for laser cutting is 350-360 nm, the peak power is 3.8-3.9 W, the beam diameter is 8.5-9.0 μm, the marking speed is 190-200 mm / s, the frequency is 100-120 kHz, the pulse width is 5-7 ns, and the pulse energy density is 25-26 J / cm 2 The laser scanning path interval is 4 to 6 μm, and the cutting speed is 90 to 100 mm / s.

[0014] Furthermore, in step 3, the hydrophobic treatment is performed by applying n-dodecyl mercaptan solution with a cotton swab and drying it, and the hydrophilic treatment is performed by applying silicone hydrophilic agent with a cotton swab and drying it.

[0015] 1. Mist collection and transport by sharp protrusions: Analysis of the forces acting on a single droplet on the surface of a sharp protrusion shows that when the included angle between the sharp protrusion and the channel is 90°, the droplet is subjected to Laplace pressure (FL), downward gravity (G), and opposing adhesion forces (FVx, FVy) from the tip to the base of the sharp protrusion. When the sharp protrusion is tilted, gravity G can be decomposed into Fy and Fx, and Fx and FL are coaxial (providing additional driving force for the droplet). According to the trigonometric cosine formula Fx = G * cos α, the smaller the included angle between the sharp protrusion and the channel, the greater the gravitational force Fx, which increases the force acting on the droplet and the transport speed. However, if the included angle between the conical protrusion and the channel is too small, liquid nucleated on the side of the adjacent conical protrusion easily forms a liquid film after condensation, thereby hindering the transport of droplets on the conical protrusion.

[0016] 2. Trapezoidal transport channel: When a droplet passes through the junction of ladder blocks without a transition arc, the forces acting on the droplet include gravity G, capillary force Fc, Laplace force FL, viscous force Fv consisting of friction and pinning forces, and boundary resistance force Fp generated by the boundary at the large end of the wedge block. Fc and FL are driving forces, while Fv and Fp are reaction forces. The resultant force F1 = G + Fc + FL - Fp - Fv. Here, FL originates from the special wedge-shaped structure, Fc originates from the multiscale rough microstructure of the grooves on the channel, and Fp originates from the boundary resistance force generated on the longitudinal boundary at the large end of the wedge, perpendicular to the droplet transport direction. Previous literature has shown that when a droplet moves through the junction of a wedge-shaped channel, it is resisted by the boundary resistance force Fp, resulting in a slowdown in transport speed or even stagnation of droplet transport. To reduce the impact of this resistance on the water transport process, a circular arc joint is used to transition the wedge-shaped connection. Because the droplets are in a passing state at the connection, the boundary resistance force of the droplets at the connection can be ignored, and the optimized channel can achieve continuous droplet transport. After using the circular arc connection, the resultant force F2 experienced by the droplet is F2 = G + Fc + F1 - Fv. Therefore, the resultant force F2 of the droplet on the wedge-shaped channel optimized with the designed circular arc shape is greater than the resultant force F1 of the droplet on the non-optimized channel, so the grouped wedge-shaped transport channel optimized with the circular arc shape can improve the transport effect.

[0017] 3. Grooved transport channel: The resultant force F3 = G + Fc + FL - Fv during the wetting process in a directional trapezoidal channel from the narrow end to the bottom. The capillary force (Fc) induced by the small grooved channel is the main driving force, while the Laplace pressure (FL) induced by the conical geometry and the liquid gravity (G) are auxiliary forces. The main resisting force is the viscous force (Fv), which consists of pinning and friction forces and is generated by contaminants or molecular interactions at the contact line, resulting in liquid-solid adhesion and hindering the movement of objects on the surface. For a channel without grooves, F4 = G + FL - Fv. The loss of the capillary force Fc reduces the resultant force F4 of the liquid on the channel, resulting in a sharp drop in the transport rate. This explains why the transport rate in a grooved channel is faster than that in a non-grooved channel when the channel geometry is the same. [Effects of the Invention]

[0018] Compared with the prior art, the present invention has the following important features:

[0019] 1. The mist collection performance and water transport performance of the mist collector are both significantly improved, with the transport speed increasing by approximately 2.8 times, eliminating droplet clogging, and achieving efficient mist collection, rapid water transport, and accelerated condensation.

[0020] 2. Integrating thermal management into the mist collector significantly improves the condensation efficiency of the mist collector, and the mist collection efficiency of the fabricated mist collector with heat dissipation film increases by 126% compared with that of the mist collector without heat dissipation film.

[0021] 3. The obtained mist collector has excellent water collection efficiency, and the mist collection efficiency of the whole mist collector is increased by 300% compared with the original mist collector. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a structural schematic diagram of the present invention. [Figure 2]Optical microscope images of the present invention, where (a) is an optical image of the copper plate layer, (a1) is an optical image of the graphene PDMS layer, (b) is a microscope image of the copper plate layer, (c) is a microscope image of the graphene PDMS layer, (d) is a locally enlarged image of the transport groove 2 on the surface of the copper plate layer, and (e) is a locally enlarged image of the graphene PDMS layer. [Figure 3] 1 is a schematic diagram of the manufacturing process of the present invention. [Figure 4] 1A and 1B are morphological representations of the present invention, where (a) is a wet image of the transport channels at the tip and tail of the sharp protrusions 111, (b) is an energy spectrum analysis image of the sharp protrusions 111, (c) is an energy spectrum analysis image of the transport grooves 2, and (d) is a scanning electron microscope image of the graphene PDMS layer. [Figure 5] FIG. 10 illustrates the mist collection efficiency of sharp protrusions 111 of different sizes according to the present invention. [Figure 6] FIG. 10 is a diagram showing mist collection efficiency at different included angles between the sharp protrusions 111 and the transport channel according to the present invention. [Figure 7] FIG. 10 is a diagram showing mist collection efficiency of different modification treatment methods of the sharp protrusions 111 according to the present invention. [Figure 8] FIG. 10 shows droplet transport velocity on different channel structures according to the present invention. [Figure 9] FIG. 10 is a diagram showing the temperature rise of graphene-PDMS heat dissipation films with different ratios according to the present invention when irradiated with a xenon lamp. [Figure 10] FIG. 10 is a diagram showing the mist collection efficiency of mist collectors equipped with different proportions of graphene-PDMS heat dissipation films according to the present invention. [Figure 11] FIG. 10 is a diagram comparing the mist collection effect of the mist collector of the present invention and the mist collector of the comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0023] The method for manufacturing a high-efficiency mist collector includes steps (1) to (3).

[0024] (1) Fabrication of copper-graphene PDMS composite heat sink fin 1: First, an 80 μm-thick copper plate was cleaned in an ultrasonic cleaner with ethanol for 10 minutes, and then washed with deionized water for further use. Next, a PDMS solution (PDMS:crosslinker mass ratio of 10:1) was thoroughly mixed with graphene powder at a mass ratio of 20:1. The crosslinker was either dibutyl phthalate or dibutyltin dilaurate. The PDMS-graphene suspension was spin-coated onto the copper plate surface at 2000 rpm for 1 minute. The Cu-PDMS sheet was then cured in a drying oven at 80°C for 4 hours to obtain a copper-graphene PDMS composite layer.

[0025] (2) Laser cutting: The copper-graphene PDMS composite layer was irradiated with a laser processing system. The laser pulse was a near-Gaussian pulse, the central wavelength was 355 nm, the peak power was 3.83 W, the beam diameter was 8.6 μm, the marking speed was 200 mm / s, the frequency was 100 kHz, the pulse width was 5 ns, and the pulse energy density was 25.89 J / cm. 2 The laser scanning path spacing is 5 μm. All sketches were first designed using the EzcadZeu software design software. Transport grooves 2 (gradient microgrooves) were etched on the copper plate at a speed of 800 mm / s. Subsequently, a two-dimensional, highly efficient mist collector structure was cut from the copper-graphene PDMS composite layer at a speed of 100 mm / s. After laser processing, the copper plate was cleaned in an ultrasonic cleaner with ethanol for 3 minutes to remove surface residue. Then, it was washed with deionized water for 3 minutes to remove the alcohol on the surface, resulting in the heat dissipation fin 1 with transport grooves 2 on its surface.

[0026] (3) Mist collector wetting performance treatment: n-dodecyl mercaptan solution is applied to the tips of the sharp protrusions 111 cut with a cotton swab to perform a hydrophobic treatment, and then dried in a drying oven at 60°C for 30 minutes, giving the tips of the sharp protrusions 111 of the mist collector superhydrophobic properties. Silicone hydrophilic agent is evenly applied with a cotton swab to the transport grooves 2 of the copper plate layer, the tail ends of the sharp protrusions 111, the trapezoidal connecting parts 112, and the connecting arcs 12 to perform a hydrophilic treatment, and then dried in a drying oven at 60°C for 30 minutes, giving the transport channels and the tail ends of the sharp protrusions 111 superhydrophilic properties.

[0027] As shown in FIGS. 1 and 2, the high-efficiency mist collector obtained in this embodiment includes a heat dissipation fin 1, which is a composite of graphene PDMS layers bonded to the top and bottom and a copper plate layer. A transport groove 2 is located in the center of the copper plate layer. The heat dissipation fin 1 includes a plurality of mist collection structural units 11, which are connected to each other in an arc-like manner by connecting arcs 12. The mist collection structural units 11 include sharp protrusions 111 and trapezoidal connecting portions 112, and a plurality of sharp protrusions 111 are symmetrically located on both sides of the trapezoidal connecting portions 112, with equal spacing between them. The tips of the sharp protrusions 111 are hydrophobic and the tails are hydrophilic. The included angle between the sharp protrusions 111 and the transport groove 2 is 30-90°. The length of the sharp protrusions is 0.5-1.1 mm, and the included angle is 10-15°. The radius of the connecting arc 12 is 1.0-1.4 mm, and the arc length is 0.6-1.0 mm. The trapezoidal connecting portion 112 has an upper base of 0.3-0.4 mm, a lower base of 0.7-0.9 mm, and a height of 2-2.5 mm. Preferably, the length of the sharp protrusion is 0.7 mm, the included angle is 12°, and the included angle between the sharp protrusion 111 and the conveying groove is 60°.

[0028] Figure 3 illustrates the fabrication process of the mist collector. After fabrication was completed, the contact angles between the hydrophobicized sharp protrusion tips and the hydrophilic transport channel were measured as 142° and 2°, respectively, as shown in Figure 4a. Energy spectroscopy (EDS) analysis of the sharp protrusion tips, as shown in Figure 4b, revealed that carbon (C), oxygen (O), and sulfur (S) elements were uniformly distributed on the surface of the SH-S2 sample, with their contents of 31.2%, 0.9%, and 0.1%, respectively. This indicates that sulfur was successfully deposited and the channel surface was successfully modified to be superhydrophobic. As shown in Figure 4c, the microstructure of the grooved channel is a typical laser-machined morphology, producing micro- and nanoscale particles through Cu melting and resolidification. The path formed by the laser spot forms the grooved channel, and therefore, the SEM image of the grooved channel appears as interconnected circular pits. Energy spectroscopy (EDS) of the channel surface revealed uniform distribution of carbon (C), oxygen (O), and silicon (Si) elements on the SH-S2 sample surface, with their respective contents of 32.8%, 18.5%, and 2.6%, respectively. This indicates that the silicone hydrophilic agent was successfully deposited, resulting in superhydrophilic modification of the channel surface. Figure 4e shows a cross-sectional SEM image of a heat-dissipating film with a 20:1 PDMS:graphene mass ratio. The PDMS is colloidal and has smooth edges, while the graphene nanosheets are very thin, with uneven edges and irregular shapes. This indicates that the graphene nanosheets are uniformly distributed throughout the composite.

[0029] To study the effect of different sizes of the sharp protrusions 111 on the mist collection efficiency, the included angles between the sharp protrusions 111 and the transport groove 2 were set to 30°, 45°, 60°, 75°, and 90°, respectively, as shown in Figure 5, the length of the sharp protrusions was set to 0.7 mm, and the included angle was set to 12°. It can be seen that when the included angle between the sharp protrusions 111 and the transport groove is 60°, the WCR is 19.89 g cm -2 h -1As shown in Figure 6, when the length of the sharp protrusions 111 is set to 0.5 mm, 0.7 mm, 0.9 mm, and 1.1 mm, the included angle is set to 12°, and the included angle between the sharp protrusions 111 and the transport groove is set to 60° and 12°, it can be seen that when the length of the sharp protrusions 111 is 0.7 mm, the WCR is 20.07 g cm -2 h -1 As shown in Figure 7, when the wettability of the sharp protrusions 111 is set to all hydrophobic (SHB), all hydrophilic (SHL), and hydrophobic at the tip and hydrophilic at the tail (SHB-SHL), the included angle between the protrusions and the transport groove is set to 60°, the included angle is set to 12°, and the length is set to 0.7 mm, the WCR is 21.25 g cm -2 h -1 This provides the highest mist collection efficiency.

[0030] Channel transport speed test: The fabricated superhydrophilic channels (SC, SCG, CC, and CCG) were sandwiched vertically and horizontally. A droplet of approximately 2 μm was placed 1 cm from the tail end of the channel. The droplet rapidly spread along the different channels. As shown in Figure 4a, at 0.03 s, the droplet transport speed on the CCG was fastest, followed by the SCG. At 0.05 s, the droplet transport speed on the CC channel equaled or even exceeded that of the SCG, and the droplet on the CCG channel reached the tail end. The droplet on the CC channel reached the bottom at 0.07 s, and finally, at 0.14 s, the droplets on all four channels reached the tail end. The transport speeds of the four channels were calculated and found to be CCG > CC > SCG > SC, as shown in Figure 8. The CCG transport speed was 200 mm s. -1 , which was approximately 2.8 times faster than the transport rate of CC.

[0031] Heat dissipation performance test of PDMS-graphene heat dissipation fins: A xenon lamp was used to irradiate composite sheets with PDMS-Graphene heat-dissipating films on their surfaces. The xenon lamp was irradiated at a power of 1 solar fluence, and the distance between the xenon lamp and the sheet was 20 cm. The surface temperatures of the composite sheets were measured after 5, 10, 20, and 30 minutes of irradiation. As can be seen, the surface temperatures of the PDMS-Graphene heat-dissipating films were consistently lower than those of the Cu surface, and the surface temperatures of the heat-dissipating films were uniform. Figure 9 shows the surface temperature rise after 30 minutes of xenon lamp irradiation when the PDMS-Graphene heat-dissipating film mass ratios were 20:1, 30:1, 40:1, and 50:1. As can be seen, the 20:1 heat-dissipating film had the lowest surface temperature but the highest heat-dissipating effect. Due to graphene's ultra-high thermal conductivity, the higher the graphene content, the higher the heat-dissipating rate of the composite film. However, experiments showed that if too much PDMS was added, it would not harden into a film, and when the graphene mass ratio was high, a weight ratio of 20:1 was the optimal ratio for film formation.

[0032] Mist collection performance test: A homemade indoor mist collection experimental system was constructed. A mist collector with sharp protrusions of different shapes and wettability was clamped in a universal sample holder. To simulate mist in a natural environment, a mist flow was generated using a humidifier (mist flow rate 370 ml / h). The distance between the sample and the humidifier nozzle was 3 cm, and the mist droplet diameter was 1-5 μm. The relative humidity in the laboratory was ≥ 90% and the temperature ≤ 25 ± 1 °C. The water collection rate (WCR) was calculated using the formula:

number

[0033] Comparative Example In this comparative example, step (3) of the above example was omitted, and the original mist collector was obtained without performing the wettability treatment.

[0034] As shown in Figure 11, a comparative analysis was performed during the initial mist collection wetting phase and the continuous mist collection phase. The mist collection performance of the optimized mist collector was significantly superior to that of the original mist collector in the comparative example. During the initial wetting phase, 1 second after the mist flow arrived at the mist collector, significantly more droplets were captured on the sharp protrusions of the mist collector of this example than on the original mist collector, and the nucleated droplets were larger. When wetting of the mist collector was complete, the volume of droplets on the sharp protrusions of the mist collector of this example was observed to be much larger than that of the original mist collector. During continuous mist collection, due to the action of surface viscous forces, the droplets collected by the original mist collector continued to coalesce and grow in size on the transport channel until channel clogging occurred, preventing smooth transport and reducing the mist collection efficiency of the sharp protrusions, preventing continuous mist collection. On the other hand, the water collected in the channels of the mist collector of this example was transported continuously without clogging the channels, and it was observed that droplets condensed on the sharp protrusions of the optimized mist collector and were transported to the channels continuously. Both of these experimental phenomena proved that the mist collector of this example has excellent water collection performance after being optimized by multiple methods.

Claims

1. A high-efficiency mist collector, comprising: a heat-dissipating fin (1) for dissipating latent heat generated when mist condenses; a transport groove (2) installed on one surface of the heat-dissipating fin (1); the heat-dissipating fin (1) comprises a plurality of mist-collecting structural units (11); the mist-collecting structural units (11) are connected to each other by connecting arcs (12) that reduce the resistance of transported droplets; the mist-collecting structural units (11) comprise sharp protrusions (111) and trapezoidal connecting portions (112); a plurality of sharp protrusions (111) are symmetrically installed on both sides of the trapezoidal connecting portions (112) at equal intervals; the tips of the sharp protrusions (111) are hydrophobic and the tails are hydrophilic; and the included angle between the sharp protrusions (111) and the transport groove (2) is 30-90°.

2. 2. The high-efficiency mist collector of claim 1, wherein the heat dissipation fin (1) comprises a composite material layer made of graphene dispersed in polydimethylsiloxane (PDMS) and a copper plate layer with a transport groove (2) at the center.

3. 2. The high-efficiency mist collector of claim 1, wherein the length of the sharp protrusions is 0.5-1.1 mm and the included angle is 10-23 degrees.

4. 2. The high-efficiency mist collector according to claim 1, wherein both the trapezoidal connecting portion (112) and the connecting arc (12) are hydrophilic.

5. 2. The high-efficiency mist collector according to claim 1, wherein the radius of the connecting arc (12) is 1.0-1.4 mm, and the arc length is 0.6-1.0 mm.

6. The high-efficiency mist collector according to claim 1, wherein the trapezoidal connecting portion (112) has an upper base of 0.3-0.4 mm, a lower base of 0.7-0.9 mm, and a height of 2-2.5 mm.

7. 2. A method for manufacturing the high-efficiency mist collector according to claim 1, comprising: Step 1: spin-coating a suspension containing polydimethylsiloxane (PDMS) and graphene onto a surface of a copper plate, and curing the suspension to obtain a composite layer in which the copper plate and a composite material layer in which the graphene is dispersed in the polydimethylsiloxane (PDMS) are laminated together; Step 2: laser cutting the composite layer into a predetermined shape and cleaning it to obtain a heat sink fin (1) with transport grooves (2) and sharp protrusions (111) on the surface; and step 3 of hydrophobizing the tip of the sharp protrusion (111) and hydrophilizing the tail end of the sharp protrusion (111), the trapezoidal connecting portion (112), and the connecting arc (12).

8. 8. The method for manufacturing a high-efficiency mist collector according to claim 7, wherein in step 1, the suspension is obtained by mixing polydimethylsiloxane (PDMS), a cross-linking agent, and graphene powder in a mass ratio of 10:1:0.2-0.5, curing at a temperature of 60-80°C for a curing time of 4-6 hours.

9. In step 2, the laser pulse for laser cutting has a central wavelength of 350-360 nm, a peak power of 3.8-3.9 W, a beam diameter of 8.5-9.0 μm, a marking speed of 190-200 mm / s, a frequency of 100-120 kHz, a pulse width of 5-7 ns, and a pulse energy density of 25-26 J / cm ２ 8. The method for manufacturing a high-efficiency mist collector according to claim 7, wherein the interval of the laser scanning path is 4-6 μm, and the cutting speed is 90-100 mm / s.

10. 8. The method for manufacturing a high-efficiency mist collector according to claim 7, wherein in step 3, the hydrophobic treatment is performed by applying an n-dodecyl mercaptan solution with a cotton swab and then drying it, and the hydrophilic treatment is performed by applying a silicone hydrophilic agent with a cotton swab and then drying it.

Images