A wetting-tunable biomimetic surface for droplet directional manipulation and collection
By combining various biomimetic surface structures, a biomimetic surface with adjustable wettability was designed, which solved the problems of low operational accuracy and high energy consumption of droplet manipulation and collection devices, realized efficient directional transport and collection of droplets, and expanded its application in microfluidics, biomedical detection and other fields.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- YANSHAN UNIV
- Filing Date
- 2025-06-27
- Publication Date
- 2026-07-31
AI Technical Summary
Existing droplet manipulation and collection devices suffer from low operational precision and high energy consumption, making it difficult to achieve directional droplet transport along complex paths. Furthermore, the existing biomimetic surface wettability control is insufficient, limiting their application in more complex scenarios.
A biomimetic surface with tunable wettability was designed, combining the wedge-shaped micro-nano structure of cactus spines, the mist-collecting gradient wettability structure of desert beetles, and the directional transport lubrication surface characteristics of pitcher plants. Through a multi-scale coupled tree-like branching topology, droplets can be rapidly converged and collected along a preset path by utilizing surface tension gradients and differences in wettability.
This improved droplet collection efficiency and flux, enabling efficient enrichment of droplets within a patterned hydrophilic confinement structure. It broke through the technical bottleneck of single-function operation and provided a new approach for developing smart surfaces that combine droplet manipulation, material separation, and energy conversion.
Smart Images
Figure CN224573773U_ABST
Abstract
Description
Technical Field
[0001] This application relates to biomimetic channel structures on metallic Ti surfaces, and more particularly to the technical field of a biomimetic surface with adjustable wettability for droplet directional manipulation and collection. Background Technology
[0002] Precise directional manipulation and efficient collection of tiny droplets are crucial in numerous fields such as microfluidics, biomedicine, and chemical analysis. Traditional droplet manipulation and collection devices suffer from several limitations, including low operational precision, high energy consumption, and difficulty in achieving directional droplet transport along complex paths. With the deepening of biomimetic research, mimicking surface structures with unique wettability found in nature, such as the wedge-shaped directional transport structure of cactus spines and the gradient wettability structure of desert beetles, has provided new insights into droplet manipulation and collection technologies. However, existing biomimetic surfaces still have shortcomings in wettability control, making it difficult to flexibly adjust surface wettability according to actual needs, thus limiting their application in more complex scenarios. Therefore, there is an urgent need to develop a biomimetic surface with tunable wettability to achieve more efficient and precise droplet directional manipulation and collection. Utility Model Content
[0003] To address the shortcomings of existing technologies, this application proposes a biomimetic surface with adjustable wettability for droplet directional manipulation and collection, which can solve at least one technical problem.
[0004] This application proposes a biomimetic surface with adjustable wettability for droplet directional manipulation and collection, comprising: a titanium substrate, a periodic papillary array composed of circular papillae, a first pit, and a second pit, wherein the periodic papillary array is located on the upper surface of the titanium substrate, and the first pit and the second pit form a tree-like pattern on the upper surface of the periodic papillary array.
[0005] Optionally, the first recess is a recess composed of a straight isosceles triangular prism and a semi-cylinder, wherein the base edge of the straight isosceles triangular prism coincides with the diameter edge of the base of the semi-cylinder, and the second recess is a triangular prism recess.
[0006] The first recess forms the trunk of the tree-like pattern, and the second recess forms the side branches of the tree-like pattern.
[0007] Optionally, the trunk of the tree-like pattern consists of four first recesses connected in a plug-in manner, with each subsequent first recess plugged into the middle of the previous first recess. The side branches consist of 18 second recesses asymmetrically distributed on both sides of the trunk, with the first bottom edge of the second recess coinciding with the waist of the isosceles right angle of the bottom surface of the first recess.
[0008] Optionally, the angle of the apex of the base of the right isosceles triangular prism is 4-10°, the height of the base of the right isosceles triangular prism is 4-8mm, the lateral edge length of the right isosceles triangular prism is 90-110μm, the base side length of the right isosceles triangular prism is 0.5-1.5mm, the diameter of the base of the semi-cylinder is 0.5-1.5mm, and the lateral edge length of the semi-cylinder is 90-110μm.
[0009] Optionally, the side length of the first base of the triangular prism is 1.18 mm, the side length of the second base is 5.35 mm, and the side length of the third base is 6.63 mm. The lateral edge length of the triangular prism is 30-90 μm.
[0010] Optionally, the diameter of the circular papillae is 300 μm, and the spacing between adjacent circular papillae is 100 μm. Optionally, the length of the titanium substrate is 20 mm, the width is 20 mm, and the thickness is 0.5 mm.
[0011] Optionally, the optimal angle of the apex of the base of the right isosceles triangular prism is 8°, the optimal height of the base of the right isosceles triangular prism is 8mm, the optimal lateral edge length of the right isosceles triangular prism is 100μm, the optimal diameter of the base of the semi-cylinder is 1.5mm, and the optimal lateral edge length of the semi-cylinder is 100μm.
[0012] This application proposes a biomimetic surface with tunable wettability for droplet directional manipulation and collection. It innovatively couples the wedge-shaped micro / nano structure of cactus spines, the gradient wettability structure for mist collection in desert beetles, and the directional transport lubrication surface characteristics of pitcher plants across multiple scales. Based on the synergistic principle of surface tension gradient and wettability differences at the micro / nano scale, the designed tree-like branching topology, driven by capillary action and surface tension in fluid mechanics, guides droplets to rapidly converge from the branch ends to the central trunk region along a predetermined path. This effectively improves droplet collection efficiency and flux, achieving efficient enrichment of droplets within a patterned hydrophilic confinement structure.
[0013] Compared to traditional single-wetting biomimetic surfaces, the hybrid wettability biomimetic surface system proposed in this invention breaks through the technical bottleneck of single function through the synergistic regulation of multiple structures, scales, and mechanisms. It provides a new technical route for developing intelligent surface materials with composite functions such as droplet manipulation, material separation, and energy conversion, and shows broad application prospects and technological expansion space in cutting-edge fields such as microfluidics, biomedical detection, and environmental monitoring and sensing. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the structure of a biomimetic surface with adjustable wettability for droplet directional manipulation and collection, according to an embodiment of this application.
[0015] Figure 2 This is a schematic diagram of the structure of the second pit of a biomimetic surface with adjustable wettability for droplet directional manipulation and collection, according to an embodiment of this application.
[0016] Figure 3 This is a schematic diagram illustrating the fabrication of a biomimetic surface with adjustable wettability for droplet directional manipulation and collection, according to an embodiment of this application.
[0017] Figure 4 This is a comparison of droplet transport efficiency after different volumes of droplets are added to the first recess of three different insertion methods using a biomimetic surface with adjustable wettability for droplet orientation manipulation and collection, according to an embodiment of this application.
[0018] Figure 5 This is a comparison of droplet transport efficiency after quantitatively adding different volumes of droplets to four different isosceles triangular prism recesses with different bottom apex angles, according to an embodiment of this application for droplet directional manipulation and collection.
[0019] Figure 6 This is a schematic diagram of the aggregation state of different droplets on a low-adhesion surface outside the dendritic pattern of a wettability-tunable biomimetic surface for droplet orientation manipulation and collection, according to an embodiment of this application.
[0020] Figure 7 This is a schematic diagram of the transport process of droplets in a tree-like pattern after quantitative dispensing by a syringe using a wettability-adjustable biomimetic surface for droplet orientation manipulation and collection, according to an embodiment of this application.
[0021] Figure 8 This is a schematic diagram of the fog collection process of a wettability-tunable biomimetic surface for droplet directional manipulation and collection, according to an embodiment of this application.
[0022] Figure 9 The wettability-tunable biomimetic surface for droplet directional manipulation and collection is an embodiment of this application, demonstrating the fog collection efficiency after ten cycles. Detailed Implementation
[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0024] In the following detailed description, reference can be made to the accompanying drawings, which form part of this application and illustrate specific embodiments of the present application. In the drawings, similar reference numerals describe substantially similar components in different figures. Specific embodiments of the present application are described in sufficient detail below to enable those skilled in the art to implement the technical solutions of the present application. It should be understood that other embodiments may also be utilized, or structural, logical, or electrical changes may be made to the embodiments of the present application.
[0025] Figure 1 A schematic diagram of a biomimetic surface with adjustable wettability for droplet directional manipulation and collection, according to an embodiment of this application, is shown below. Figure 1 As shown, the biomimetic surface for droplet manipulation proposed in this application includes:
[0026] The titanium substrate S101, circular papillae S102, first pit S103, and second pit S104 are provided. The periodic papillae array formed by the circular papillae S102 is located on the upper surface of the titanium substrate S101, and the tree-like pattern formed by the first pit S103 and the second pit S104 is located on the upper surface of the periodic papillae array.
[0027] The biomimetic surface with adjustable wettability proposed in this application for droplet directional manipulation and collection has different interface structures, enabling the surface to have different droplet manipulation capabilities. The periodic papillary array is superhydrophobic, and the tree-like pattern composed of the first pit S103 and the second pit S104 is superhydrophilic, enabling droplets to gather from the tip of the second pit S104 and the surface of the periodic papillary array towards the middle first pit S103, achieving rapid droplet transport and collection through a wettability gradient.
[0028] like Figure 1 As shown, the first recess S103 is a recess composed of a straight isosceles triangular prism and a semi-cylinder, wherein the base edge of the straight isosceles triangular prism coincides with the diameter edge of the base of the semi-cylinder. The second recess S104 is a triangular prism recess. The first recesses S103 form the trunk of the tree-like pattern, and the second recesses S104 form the side branches of the tree-like pattern. The trunk of the tree-like pattern is formed by four first recesses S103 connected in a plug-in manner, with each subsequent first recess S103 plugged into the middle of the previous first recess S103. The side branches are formed by 18 second recesses S104 asymmetrically distributed on both sides of the trunk, with the first bottom edge of the second recess coinciding with the waist of the isosceles right angle of the bottom surface of the first recess.
[0029] Figure 2The schematic diagram illustrates the structure of the second recess S104 of the biomimetic surface with adjustable wettability for droplet orientation manipulation and collection, as described in an embodiment of this application. Figure 2 As shown, the side length of the first base edge S201 of the triangular prism is 1.18 mm, the side length of the second base edge S202 is 5.35 mm, and the side length of the third base edge S203 is 6.63 mm. The length of the lateral edge S204 of the triangular prism is 30-90 μm.
[0030] In some embodiments of this application, the diameter of the circular papillae is 300 μm, and the spacing between adjacent circular papillae is 100 μm. The titanium substrate has a length of 20 mm, a width of 20 mm, and a thickness of 0.5 mm.
[0031] In some embodiments of this application, the angle of the apex of the base of the right isosceles triangular prism is preferably 8°, the height of the base of the right isosceles triangular prism is preferably 8mm, the side edge length of the right isosceles triangular prism is preferably 100μm, the diameter of the base of the semi-cylinder is preferably 1.5mm, and the side edge length of the semi-cylinder is preferably 100μm.
[0032] Figure 3 The illustration schematically depicts the fabrication of a biomimetic surface with adjustable wettability for droplet directional manipulation and collection, according to an embodiment of this application, including:
[0033] S1 The surface of the titanium sheet was sanded with sandpaper and then ultrasonically cleaned with anhydrous ethanol and deionized water for 10 minutes.
[0034] S2 performs laser processing on the surface of the pretreated titanium sheet described in S1 to obtain a superhydrophilic titanium sheet substrate with a periodic papillary array on the surface of the titanium sheet.
[0035] S3. Place the titanium substrate from S2 into a drying oven and dry it at 160°C for 120 min to obtain a superhydrophobic titanium sheet substrate.
[0036] S4 performs a second laser processing on a selected area of the dry titanium surface to create a tree-like pattern structure. The main trunk consists of four interlocking first recesses, each 8 mm long and with an 8° apex angle on the bottom surface. The side branches consist of 18 asymmetrically distributed second recesses on both sides of the main trunk, with the first bottom edge of each second recess coinciding with the waist of the isosceles right angle formed by the bottom surface of the first recess. The parameters for the second laser processing are: a line fill spacing of 0.01 mm; laser intensities of 20 W, 25 W, 30 W, and 35 W for processing the four first recesses of the main trunk; a scanning speed of 500 mm / s; a laser frequency of 20 kHz; and 30 scans. For processing the 18 side branches, the laser intensity is 20 W, the scanning speed is 500 mm / s, the laser frequency is 20 kHz, and the number of scans is 30, resulting in a hydrophilic tree-like pattern structure.
[0037] This application proposes a biomimetic surface with tunable wettability for droplet directional manipulation and collection. It innovatively couples the wedge-shaped micro / nano structure of cactus spines, the mist-collecting gradient wettability structure of desert beetles, and the directional transport lubrication surface characteristics of pitcher plants across multiple scales. Based on the synergistic effect of surface tension gradient and wettability differences at the micro / nano scale, the designed tree-like branching topology exhibits excellent droplet directional transport and collection capabilities. Utilizing capillary action and surface tension-driven mechanisms in fluid mechanics, it guides droplets along a pre-defined path from the branch ends to the central trunk region, effectively improving droplet collection efficiency and flux, and achieving efficient enrichment of droplets within a patterned hydrophilic confinement structure.
[0038] The structural features of the multiple biomimetic surfaces proposed in this utility model have been described above through multiple embodiments. The technical advantages of the multiple biomimetic surfaces proposed in this application will be verified through specific embodiments below.
[0039] Example 1
[0040] To verify the optimal insertion method of the first pit S103 of the biomimetic surface with adjustable wettability for droplet directional manipulation and collection proposed in this application, the following experiment was conducted:
[0041] Different volumes of droplets were quantitatively added to the first recesses with three different insertion methods, and the droplet transport efficiency was calculated. The three insertion methods were: the second first recess S103 was inserted into the first first recess S103 at 1 / 2, the second first recess S103 was inserted into the first first recess S103 at 1 / 3, and the second first recess S103 was inserted into the first first recess S103 at 1 / 4.
[0042] Droplets of 4 μL, 6 μL, 8 μL, and 10 μL were added to the tip of the first recess S103 with three different insertion methods, and the droplet transport efficiency was calculated. Figure 4 The illustration schematically demonstrates the transport efficiency of droplets of different volumes after being dropped into the first recesses of three different insertion methods using a wettability-tunable biomimetic surface for droplet orientation manipulation and collection, according to an embodiment of this application. Figure 4 As shown, overall, when the next first recess S103 is inserted into half of the previous first recess S103, the droplet transport rate is relatively high, proving that the insertion method is optimal when the next first recess S103 is inserted into half of the previous first recess S103.
[0043] Example 2
[0044] To verify the optimal angle of the apex angle of the bottom surface of the right isosceles triangular prism recess of the biomimetic surface with adjustable wettability for droplet directional manipulation and collection proposed in this application, the following experiment was conducted:
[0045] Four types of right isosceles triangular prism depressions with different base apex angles were prepared, and the transport efficiency of the droplets was calculated after quantitatively adding different volumes of liquid to them. The four types of right isosceles triangular prism depressions with different base apex angles are: the first right isosceles triangular prism with a base apex angle of 4°, the second right isosceles triangular prism with a base apex angle of 6°, the third right isosceles triangular prism with a base apex angle of 8°, and the fourth right isosceles triangular prism with a base apex angle of 10°.
[0046] Droplets of 2 μL, 4 μL, 6 μL, and 8 μL were added to the tips of the apex angles of the bottom surfaces of four different right isosceles triangular prisms. Figure 5 The illustration schematically shows a comparison of droplet transport efficiency after quantitatively adding different volumes of droplets to four different isosceles triangular prism recesses with different apex angles on four different base surfaces using a wettability-adjustable biomimetic surface for droplet orientation manipulation and collection, as described in the embodiments of this application. Figure 5 As shown, when the apex angle of the bottom surface of the third straight isosceles triangular prism is 8°, it can transport farther or complete more droplet transport per unit time under different droplet volumes, proving that the transport efficiency is optimal when the apex angle of the bottom surface of the straight isosceles triangular prism is 8°. Therefore, the optimal angle of the apex angle of the bottom surface of the first pit S103 is 8°.
[0047] Example 3
[0048] To verify the superhydrophobic properties beyond the dendritic pattern of the biomimetic surface with tunable wettability proposed in this application for droplet directional manipulation and collection, the following experiments were conducted:
[0049] Five droplets were dropped onto a low-adhesion surface outside the tree pattern, and the aggregation state of the droplets was observed. The five droplets were tea, cola, Sprite, milk, and orange juice. Figure 6 This illustration schematically depicts the aggregation states of different droplets on a low-adhesion surface outside a dendritic pattern, utilizing a wettability-tunable biomimetic surface for droplet orientation manipulation and collection, according to embodiments of this application. Figure 6 As shown, the five droplets exhibit a spherical shape on the surface, indicating a high water contact angle. This demonstrates that the fabricated structured surface can achieve ultra-high water contact angles in various media. Introducing specific interface structures into the periodic papillary array structure can create structural and functional cross-links. The combination of the unique site wetting properties and superhydrophobic properties brought about by the specific interface structure allows for the construction of biomimetic surfaces with excellent droplet orientation manipulation and collection.
[0050] Example 4
[0051] To verify the overall coherence of the dendritic pattern structure of the wettability-tunable biomimetic surface proposed in this application for droplet directional manipulation and collection, the following experiments were conducted:
[0052] The tree-like pattern structure of this embodiment is placed horizontally with its face upward. Water droplets are stained with litmus reagent, and quantitative droplet testing is performed using a syringe to observe the movement state of the stained water droplets. Figure 7 This illustration schematically depicts the transport process of droplets in a tree-like pattern after quantitative dispensing via a syringe, using a wettability-adjustable biomimetic surface for droplet orientation manipulation and collection, according to an embodiment of this application. Figure 7 As shown, when a droplet contacts the tip of the main trunk of the hydrophilic dendritic pattern, it is rapidly transported towards the trunk and fills the side branches, completing the entire dendritic pattern structure in 0.42 seconds. This demonstrates the excellent continuity between the main trunk and side branches of the dendritic pattern structure in transporting droplets.
[0053] Example 5
[0054] To verify the performance of the biomimetic surface with tunable wettability proposed in this application for droplet directional manipulation and collection in collecting tiny droplets from fog, the following experiments were conducted:
[0055] The process of fixing the biomimetic surface with adjustable wettability for droplet directional manipulation and collection proposed in this application into the built spray system for mist collection, with the spray distance controlled at 15cm, the spray humidity set at 50%, and the temperature at 23℃, is carried out. Figure 8 This diagram schematically illustrates a fog-collecting process using a wettability-tunable biomimetic surface for droplet directional manipulation and collection, according to an embodiment of this application. Figure 8 As shown, the fog collection process changes over time, with the 1-minute fog collection process from left to right representing 10 seconds, 20 seconds, 40 seconds, and 60 seconds respectively. At 10 seconds, only a small number of fine fog droplets adhere to the side branches. At 20 seconds, the number of fog droplets gradually increases, and they begin to accumulate significantly on the trunk, forming small droplet clusters and expanding the coverage. At 40 seconds, the droplets further converge and grow, some small droplets merge, the surface droplet distribution becomes denser, and the tree-like pattern is clearly covered by fog droplets. By 60 seconds, the fog droplets continue to grow and merge, and the number of large droplets increases significantly and drips, demonstrating the good performance of this invention in collecting tiny droplets.
[0056] Example 6
[0057] To verify the stable performance of the biomimetic surface with tunable wettability for droplet orientation manipulation and collection proposed in this application in collecting tiny droplets from fog, the following experiment was conducted:
[0058] The biomimetic surface with adjustable wettability proposed in this application for droplet directional manipulation and collection was placed in air for 7 days, then fixed in a constructed spray system. The spray distance was controlled at 15 cm, the spray humidity was set at 50%, and the temperature was 23°C. Fog collection was performed and the fog collection efficiency was calculated. Figure 9The illustration schematically demonstrates the fog collection efficiency of a wettability-tunable biomimetic surface for droplet orientation manipulation and collection after ten cycles. (Example) Figure 9 As shown, after ten cycles of experimentation, the average fog collection efficiency of this embodiment was verified to be 7.725 g cm⁻¹. -2 h -1 This demonstrates that the fog collection efficiency of this embodiment is significantly higher than that of other structures and that the interface structure has good stability.
[0059] In summary, a biomimetic surface with tunable wettability for droplet directional manipulation and collection possesses advantages such as stable wettability, precise and controllable structural parameters, and high processing accuracy. It can effectively grasp droplets and controllably alter their trajectory, demonstrating potential advantages in the field of microfluidics. Furthermore, compared to traditional single-wetting biomimetic surfaces, the hybrid wettability biomimetic surface proposed in this application, through the synergistic control of multiple structures, scales, and mechanisms, breaks through the technical bottleneck of single-function applications, providing a new approach for developing intelligent surfaces with combined functions such as droplet manipulation, matter separation, and energy conversion.
[0060] The above embodiments are for illustrative purposes only and are not intended to limit the scope of this application. Those skilled in the art can make various changes and modifications without departing from the scope of this application. Therefore, all equivalent technical solutions should also fall within the scope of this application.
Claims
1. A wetting-tunable biomimetic surface for droplet directed manipulation and collection, characterized in that, include: The device comprises a titanium substrate, a periodic array of circular papillae, a first pit, and a second pit, wherein the periodic array of papillae is located on the upper surface of the titanium substrate, and the first pit and the second pit form a tree-like pattern on the upper surface of the periodic array of papillae.
2. The wettability switchable biomimetic surface for droplet directed manipulation and collection according to claim 1, wherein, The first recess is a recess composed of a straight isosceles triangular prism and a semi-cylinder, wherein the base edge of the straight isosceles triangular prism coincides with the diameter edge of the base of the semi-cylinder, and the second recess is a triangular prism recess. The first recess forms the trunk of the tree-like pattern, and the second recess forms the side branches of the tree-like pattern.
3. The wetting-tuneable biomimetic surface for droplet directed manipulation and collection according to claim 2, characterized in that, The trunk of the tree-like pattern consists of four first recesses connected by a plug-in mechanism, with each subsequent first recess plugged into the middle of the previous first recess. The side branches of the tree-like pattern consist of 18 second recesses asymmetrically distributed on both sides of the trunk. The first bottom edge of the second recess coincides with the waist of the isosceles right angle of the bottom surface of the first recess.
4. The wettability switchable surface for droplet directed manipulation and collection according to claim 2, wherein, The angle of the apex of the base of the right isosceles triangular prism is 4-10°, the height of the base of the right isosceles triangular prism is 4-8mm, the lateral edge length of the right isosceles triangular prism is 90-110μm, the base side length of the right isosceles triangular prism is 0.5-1.5mm, the diameter of the base of the semi-cylinder is 0.5-1.5mm, and the lateral edge length of the semi-cylinder is 90-110μm.
5. A biomimetic surface with adjustable wettability for droplet directional manipulation and collection according to claim 2, characterized in that, The first base edge of the triangular prism has a side length of 1.18 mm, the second base edge has a side length of 5.35 mm, and the third base edge has a side length of 6.63 mm; the lateral edge length of the triangular prism is 30-90 μm.
6. The wetting-tuneable biomimetic surface for droplet directional manipulation and collection according to claim 1, characterized in that, The diameter of the circular papillae is 300 μm, and the distance between adjacent circular papillae is 100 μm.
7. The wetting-tuneable biomimetic surface for droplet directional manipulation and collection according to claim 1, characterized in that, The titanium substrate has a length of 20 mm, a width of 20 mm, and a thickness of 0.5 mm.
8. The wettability switchable surface for droplet directed manipulation and collection according to claim 4, wherein, The optimal angle of the apex of the base of the right isosceles triangular prism is 8°, the optimal height of the base of the right isosceles triangular prism is 8mm, the optimal side length of the right isosceles triangular prism is 100μm, the optimal diameter of the base of the semi-cylinder is 1.5mm, and the optimal side length of the semi-cylinder is 100μm.