Method and device for preparing self-assembled structure
By establishing a temperature gradient at the liquid-gas interface to generate a Marangoni flow field, particles are driven to self-assemble and continuously transfer to the matrix, solving the control problem of self-assembly in industrial applications and realizing efficient and stable production of self-assembled structures.
Patent Information
- Application Number
- CN202510766400.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-10
- Publication Date
- 2025-10-28
AI Technical Summary
Existing self-assembly methods have problems in industrial applications, such as demanding control conditions, low output, long time consumption, and stringent environmental requirements, making it difficult to meet industrialization needs.
By arranging two symmetrical heat sources at the liquid-gas interface, a temperature gradient is established to generate a Marangoni flow field. The flow field is used to drive the particles to be assembled to form a densely packed self-assembled structure. The self-assembled structure is then continuously picked up by the matrix, thus achieving continuous production.
It achieves improved stability and yield of self-assembly structures, adapts to industrial needs, reduces the severity of environmental conditions, and improves self-assembly efficiency and area.
Smart Images
Figure CN120838487A_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of self-assembly technology, and in particular to a method and apparatus for preparing self-assembled structures. Background Technology
[0002] Self-assembly refers to a technique in which basic structural units (e.g., molecules, nanomaterials, substances at the micrometer or larger scale) spontaneously form ordered structures. During self-assembly, the basic structural units spontaneously organize or aggregate into a stable structure with a certain regular geometric appearance through non-covalent interactions.
[0003] Self-assembly methods can conveniently grow monodisperse nanoparticles in solution into periodic structures, including convection self-assembly, dip-coating, interfacial self-assembly, electrostatic self-assembly, electrophoretic self-assembly, and liquid-gas interfacial self-assembly.
[0004] However, existing self-assembly methods still face bottlenecks in practical industrial applications. Firstly, the control conditions for the self-assembly process are too stringent; secondly, the output of self-assembly is too low to meet industrial needs; and thirdly, continuous self-assembly equipment is time-consuming and requires stringent environmental conditions. Summary of the Invention
[0005] The purpose of this disclosure is to provide a method and apparatus for preparing self-assembled structures to solve at least some of the problems mentioned in the background art or other similar problems.
[0006] According to one aspect of the present disclosure, a method for preparing a self-assembled structure is provided, comprising: establishing a temperature gradient at the liquid-gas interface, with the temperature decreasing from the two heat sources toward the reference plane, by means of two heat sources arranged on a liquid-gas interface and symmetrical about a reference plane perpendicular to the liquid-gas interface, to generate two Marangoni flow fields flowing toward the reference plane from the two heat sources on the liquid-gas interface; providing particles to be assembled to the liquid-gas interface, the particles aggregating toward the reference plane and forming a densely packed self-assembled structure under the action of the two Marangoni flow fields; and transferring the self-assembled structure onto a substrate.
[0007] In some embodiments, establishing a temperature gradient at the liquid-gas interface, with the temperature decreasing from the two heat sources toward the reference plane, by means of two heat sources arranged on a liquid-gas interface and symmetrical about a reference plane perpendicular to the liquid-gas interface, includes: maintaining the temperature gradient by continuously increasing the temperature of the heat sources, or by keeping the temperature of the heat sources constant and continuously cooling the liquid-gas interface, so that the two Marangoni flow fields continue to exist; providing particles to be assembled to the liquid-gas interface includes: continuously supplying particles to be assembled to the liquid-gas interface to continuously form the self-assembled structure; transferring the self-assembled structure onto a substrate includes: continuously picking up the self-assembled structure by continuously moving a substrate through the liquid-gas interface.
[0008] In some embodiments, the liquid-gas interface is the surface of a liquid phase; the continuous cooling of the liquid-gas interface includes: continuously cooling the liquid-gas interface by means of a cooling device arranged in the liquid phase.
[0009] In some embodiments, the matrix has a pickup surface for picking up the self-assembled structure; the provision of the particles to be assembled to the liquid-gas interface includes: continuously supplying a dispersion containing the particles to be assembled to the liquid-gas interface on the side of the liquid-gas interface facing the pickup surface, wherein the flow field formed by the dispersion continuously pushes the self-assembled structure toward the pickup surface of the matrix, so that the self-assembled structure is continuously picked up by the pickup surface of the matrix.
[0010] In some embodiments, the flow directions of the two Marangoni flow fields at the liquid-gas interface are respectively a first direction and a second direction from the two heat sources toward the reference surface and perpendicular to the reference surface, wherein the first direction and the second direction are opposite; the flow direction of the flow field formed by the dispersion liquid at the liquid-gas interface is a third direction toward the matrix, wherein the third direction is perpendicular to the first direction and the second direction.
[0011] In some embodiments, the substrate is a thin film, and the intersection line between the thin film and the liquid-gas interface is perpendicular to the reference plane.
[0012] In some embodiments, providing the particles to be assembled to the liquid-gas interface includes: supplying a dispersion containing the particles to be assembled to the liquid-gas interface via a feeding panel, wherein the feeding panel is inclined relative to and in contact with the liquid-gas interface, and the particles to be assembled in the dispersion are pre-spread on the feeding panel before entering the liquid-gas interface.
[0013] In some embodiments, the upper end of the feeding panel is provided with a plurality of feeding ports, the lower end of the feeding panel is in contact with the liquid-gas interface, the plurality of feeding ports are arranged at equal intervals in a direction perpendicular to the reference plane, and the plurality of feeding ports are at the same height relative to the liquid-gas interface; the step of providing the particles to be assembled to the liquid-gas interface includes: supplying a dispersion containing the particles to be assembled simultaneously and at the same supply rate through the plurality of feeding ports.
[0014] In some embodiments, the liquid-gas interface is the surface of water; the particles to be assembled are hydrophobic particles; the feeding panel is a hydrophilic panel; and the liquid of the dispersion is water or a hydrophilic liquid.
[0015] In some embodiments, the liquid-gas interface is the liquid surface of the liquid phase, the two Marangoni flow fields converge at the reference surface, and form two flow field vortices symmetrical to the reference surface in the liquid phase, the two flow field vortices being located between the two heat sources and the reference surface respectively.
[0016] According to another aspect of the present disclosure, an apparatus for preparing a self-assembled structure is provided, comprising: a liquid pool containing a liquid phase having a liquid-gas interface exposed to a gas phase environment; two heat sources arranged on the liquid-gas interface and symmetrical about a reference plane perpendicular to the liquid-gas interface, wherein a temperature gradient decreasing from the two heat sources toward the reference plane is established on the liquid-gas interface by the two heat sources to generate two Marangoni flow fields flowing toward the reference plane from the two heat sources; a feeding device for supplying particles to be assembled to the liquid-gas interface, the particles aggregating toward the reference plane under the action of the two Marangoni flow fields and forming a densely packed self-assembled structure; and a substrate for picking up the self-assembled structure.
[0017] In some embodiments, the liquid pool has two opposing sidewalls, and two heat sources are respectively fixed to the inner surfaces of the two sidewalls. A portion of each heat source is located in the liquid phase, and another portion of each heat source is located in the gas phase environment.
[0018] In some embodiments, the feeding device is a feeding panel, which is inclined relative to and in contact with the liquid-gas interface. The upper end of the feeding panel is provided with a plurality of feeding ports, and the lower end of the feeding panel is in contact with the liquid-gas interface. The plurality of feeding ports are arranged at equal intervals in a direction perpendicular to the reference plane, and the plurality of feeding ports are at the same height relative to the liquid-gas interface.
[0019] In some embodiments, the apparatus for preparing a self-assembled structure further includes a cooling device disposed within the liquid pool for continuously cooling the liquid and liquid-gas interface within the liquid pool to maintain the temperature gradient.
[0020] In some embodiments, the substrate is a thin film that continuously picks up the self-assembled structure by continuously moving through the liquid-gas interface.
[0021] The embodiments disclosed herein utilize temperature differences to construct a stable and long-lasting opposing Marangoni flow field, based on which the continuous self-assembly of the particles to be assembled can be achieved. Attached Figure Description
[0022] To more clearly illustrate the technical solutions in the embodiments or prior art of this specification, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:
[0023] Figure 1 This is a schematic flowchart of a method for preparing a self-assembled structure according to an embodiment of the present disclosure;
[0024] Figure 2 This is a schematic diagram of the self-assembly principle at the liquid-gas interface in an embodiment of this disclosure;
[0025] Figure 3 This is a schematic diagram of the distribution of the Marangoni flow field in an embodiment of this disclosure;
[0026] Figure 4 This is a schematic diagram of the apparatus for preparing a self-assembled structure according to an embodiment of the present disclosure. Detailed Implementation
[0027] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. Based on the embodiments in this specification, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this specification.
[0028] In the embodiments of this disclosure, the terms "first," "second," etc., are used to distinguish different elements by name, but do not indicate the spatial arrangement or chronological order of these elements, and these elements should not be limited by these terms. The term "and / or" includes any one or more of the terms listed in association and all combinations thereof. The terms "comprising," "including," "having," etc., refer to the presence of the stated features, elements, components, or assemblies, but do not exclude the presence or addition of one or more other features, elements, components, or assemblies.
[0029] In the embodiments of this disclosure, the singular forms "a," "the," etc., may include the plural forms and should be broadly understood as "a kind" or "a class" rather than limited to the meaning of "one." Furthermore, the term "the" should be understood to include both the singular and plural forms unless the context explicitly indicates otherwise. Furthermore, the term "according to" should be understood as "at least partially based on..." and the term "based on" should be understood as "at least partially based on..." unless the context explicitly indicates otherwise. Furthermore, the term "a plurality" means two or more, unless otherwise stated.
[0030] The adjective or adverbial modifiers “up” and “down”, “clockwise” and “counterclockwise”, “front” and “back”, “left” and “right”, “top” and “bottom”, “inner” and “outer” used in this article are only for the convenience of relative reference between multiple sets of terms and do not describe any specific directional restrictions on the modified terms.
[0031] The embodiments of this disclosure will now be described with reference to the accompanying drawings.
[0032] An embodiment of the first aspect of this disclosure provides a method for preparing a self-assembled structure. Figure 1 This illustration shows a flowchart of a method for preparing a self-assembled structure according to an embodiment of the present disclosure. Figure 2 This diagram illustrates the self-assembly principle at the liquid-gas interface in an embodiment of this disclosure. Figure 3 This diagram shows the distribution of the Marangoni flow field in an embodiment of this disclosure. Figure 4 A schematic diagram of an apparatus for preparing a self-assembled structure is shown, which is used in the method of an embodiment of this disclosure.
[0033] like Figures 1 to 4 As shown, the method for preparing a self-assembled structure according to this embodiment includes the following steps:
[0034] Step S100: By arranging two heat sources 2 on a liquid-gas interface 100 and symmetrical about a reference plane P perpendicular to the liquid-gas interface 100, a temperature gradient with decreasing temperature from the two heat sources 2 toward the reference plane P is established on the liquid-gas interface 100, so as to generate two Marangoni flow fields flowing in opposite directions from the two heat sources 2 toward the reference plane P on the liquid-gas interface 100.
[0035] Step S200: Provide particles 200 to be assembled to the liquid-gas interface 100. Under the influence of two Marangoni flow fields, the particles 200 aggregate toward the reference plane P and form a densely packed self-assembled structure; and
[0036] Step S300: Transfer the self-assembled structure onto the substrate 3.
[0037] It should be noted that the execution order of steps S100, S200 and S300 is not limited in the present embodiments. These steps can be executed simultaneously, sequentially, or some steps can be executed simultaneously.
[0038] In step S100, the liquid-gas interface 100 refers to the liquid surface exposed to the gas phase. Figure 4 In the example, the liquid phase can be a liquid contained in a liquid pool 1, and the liquid can be deionized water. The gas phase can be air. The liquid pool 1 can be surrounded by side walls and a bottom wall. The top of the liquid pool 1 can be open, so the liquid surface in the liquid pool 1 is in contact with the air to form a liquid-gas interface 100. The shape of the liquid pool 1 can be square, and the side walls of the liquid pool 1 can be transparent plates to facilitate observation of the self-assembly process in the liquid pool 1.
[0039] In step S100, see Figure 3 The reference plane P is an imaginary plane; the two heat sources 2 are symmetrical with respect to the reference plane P, which means that the distances between the two heat sources 2 and the reference plane P are approximately equal, and the two heat sources 2 face each other.
[0040] In step S100, the two heat sources 2 can have the same shape and the same temperature, so as to establish the same temperature gradient on both sides of the reference surface P, thereby generating a Marangoni flow field symmetrical with respect to the reference surface P on both sides of the reference surface P.
[0041] For example, such as Figure 4 As shown, the two heat sources 2 can be two heating plates. The two heating plates can be arranged on opposite sides of the reference plane P in a manner parallel to the reference plane P and facing each other, with equal spacing between the two heating plates and the reference plane P. For example, the two heating plates can be fixed to the inner surfaces of two opposite side walls of the liquid pool 1, with a portion of each heating plate located in the liquid within the liquid pool 1 and the other portion located in the air. Therefore, when the temperature of the heating plate is higher than the temperature of the liquid within the liquid pool 1, the heat from the heating plate will be transferred to the liquid within the liquid pool 1, causing the temperature of the liquid and liquid-gas interface 100 to rise and the temperature to be distributed in a gradient in the direction away from the heat source 2.
[0042] For example, two heat sources 2 can be electrically connected to a controller to control the heating temperature of the heat sources 2. Two heat sources 2 can be electrically connected to the same controller to synchronously control the two heat sources 2 through one controller, but this application is not limited thereto. Two heat sources 2 can also be electrically connected to two separate controllers to control the two heat sources 2 separately through two separate controllers.
[0043] In this embodiment of the disclosure, the two heat sources 2 heat the liquid phase, thereby establishing a temperature gradient on the liquid-gas interface 100 that decreases in temperature from the two heat sources 2 toward the reference surface P, thereby generating two Marangoni flow fields on the liquid-gas interface 100 that flow in opposite directions from the two heat sources 2 toward the reference surface P. These two Marangoni flow fields are used to drive the self-assembly of the particles 200 to be assembled.
[0044] Figure 3 The distribution of temperature and Marangoni flow field in the liquid within pool 1 is shown. Specifically, Figure 3 The display shows the temperature and Marangoni flow field distribution at a cross-section of the liquid in the liquid pool 1, which is perpendicular to the reference plane P and the liquid-gas interface 100 and passes through the center of the two heat sources 2. Figure 3 The horizontal axis represents the width of the liquid in the pool in the direction perpendicular to the reference plane P. Figure 3 The left vertical axis represents the height of the liquid in the liquid pool in the direction perpendicular to the liquid-gas interface (100°). Figure 3 The right-hand vertical axis represents the temperature difference between the liquid temperature and room temperature (for example, 0 on the vertical axis represents room temperature, and 40 on the vertical axis represents a temperature 40 degrees Celsius higher than room temperature).
[0045] Figure 3 The direction of the arrow in the diagram indicates the flow direction of the Marangoni flow field, and the length of the arrow indicates the flow velocity of the Marangoni flow field. The longer the arrow, the greater the flow velocity of the Marangoni flow field, and the shorter the arrow, the smaller the flow velocity of the Marangoni flow field. Figure 3 The horizontal line at the top of the yellow area represents the liquid-gas interface 100, and the gaps on both sides of the yellow area represent the location of the heat source 2 (e.g., the heating plate). Figure 3 The background color in the image represents temperature. Yellow represents higher temperatures, and within the yellow area, the light yellow area is warmer than the dark yellow area. Red represents lower temperatures, and purple represents even lower temperatures.
[0046] like Figure 3 As shown, the liquid-gas interface 100 has the highest temperature near the two heat sources 2 and the lowest temperature at the reference surface P, thus generating two temperature gradients on the liquid-gas interface 100 that decrease in temperature from the two heat sources 2 to the reference surface P. Induced by these two temperature gradients, two Marangoni flow fields are generated on the liquid-gas interface 100.
[0047] For example Figure 3As shown, at the liquid-gas interface 100, the Marangoni flow field on the left flows from the left heat source 2 towards the reference surface P (to the right), and the Marangoni flow field on the right flows from the right heat source 2 towards the reference surface P (to the left). The two opposing Marangoni flow fields converge at the reference surface P and then flow downwards, thus forming two symmetrical flow field vortices in the liquid phase relative to the reference surface P. The two flow field vortices are located between the two heat sources 2 and the reference surface P, respectively. Figure 3 The flow field vortex on the left side flows clockwise, while the flow field vortex on the right side flows counterclockwise. The presence of these two flow field vortices contributes to the stability of the Marangoni flow field, which in turn facilitates the smooth self-assembly process.
[0048] For example Figure 3 As shown, the flow velocities of the two Marangoni flow fields at the liquid-gas interface 100 decrease from their respective heat sources 2 toward the reference surface P. That is, the flow velocities of the two Marangoni flow fields are greatest near the two heat sources 2 at the liquid-gas interface 100, and smallest at the reference surface P far from the heat sources 2. This is also beneficial for self-assembly, which will be introduced below.
[0049] In step S200, see Figure 2 The particles 200 to be assembled provided to the liquid-gas interface 100 can be nanoparticles or microparticles, for example, the particles 200 to be assembled can be colloidal particles. Figure 2 The red arrows in the diagram represent the flow directions of the two Marangoni flow fields at the liquid-gas interface 100. Due to the presence of two opposing Marangoni flow fields at the liquid-gas interface 100, the particles 200 to be assembled overcome the electrostatic repulsion between them under the drive of the two Marangoni flow fields, gather toward the reference plane P, and form a densely packed self-assembled structure.
[0050] Preferably, the particles 200 to be assembled are provided in a dispersed state to the liquid-gas interface 100 in order to form a self-assembled structure arranged in a single layer.
[0051] It is understandable that, due to the presence of two opposing Marangoni flow fields at the liquid-gas interface 100, the particles 200 to be assembled located on both sides of the reference plane P will simultaneously converge towards the reference plane P under the drive of their respective Marangoni flow fields (e.g., ...). Figure 2As shown in the diagram, in other words, the two groups of particles 200 to be assembled, located on either side of the reference plane P, move simultaneously towards the same aggregation center line (i.e., the intersection of the reference plane P and the liquid-gas interface 100) (i.e., bidirectional aggregation). Compared with unidirectional aggregation, this allows for faster self-assembly into a self-assembly structure, thereby effectively improving self-assembly efficiency. Furthermore, since all particles 200 to be assembled converge towards the same aggregation center line, the arrangement of the particles 200 is more compact, resulting in better self-assembly and greater stability of the self-assembly structure, making it less likely for them to disperse after self-assembly. Additionally, the resulting self-assembly structure can be controlled through process parameters to be a multi-layered or porous structure.
[0052] In addition, since all the particles 200 to be assembled are gathered toward the reference plane P, the particles to be self-assembled at the reference plane P will be the first to complete self-assembly and form the middle part of the self-assembled structure. Since the flow velocity of the Marangoni flow field at the reference plane P is the smallest (for example, approximately zero), the particles that complete self-assembly first can remain stable and are not driven by the Marangoni flow field. That is, the middle part of the self-assembled structure remains stable and does not move further, thereby further improving the stability of the entire self-assembled structure.
[0053] Furthermore, the two opposing Marangoni flow fields provide a larger self-assembly space, enabling large-area self-assembly and resulting in larger self-assembled structures, especially in the direction perpendicular to the reference plane P, where the self-assembled structure can have a larger width.
[0054] In step S300, the substrate 3 used can be a substrate or a thin film. For example, the substrate can be a silicon substrate; the thin film is a flexible thin film, preferably a hydrophilic thin film, for example, the material of the thin film can be a polyimide film. Since there is an adhesive force between the thin film and the particles of the self-assembled structure, the thin film can pick up the self-assembled structure.
[0055] For example, the self-assembled structure on the liquid-gas interface 100 can be transferred to the substrate 3 by tilting and picking up, or the substrate 3 can be configured to continuously move through the liquid-gas interface 100, and the substrate 3 picks up the self-assembled structure on the liquid-gas interface 100 during the movement.
[0056] In some embodiments, step S100 includes maintaining a temperature gradient by continuously increasing the temperature of the heat source 2, or by keeping the temperature of the heat source 2 constant and continuously cooling the liquid-gas interface 100, so that the two Marangoni flow fields continue to exist; step S200 includes continuously supplying the particles to be assembled 200 to the liquid-gas interface 100 to continuously form a self-assembled structure; step S300 includes continuously picking up the self-assembled structure by continuously moving the substrate 3 through the liquid-gas interface 100.
[0057] In this embodiment, by maintaining the temperature gradient, the two Marangoni flow fields are continuously maintained, providing continuous power for continuous self-assembly; by continuously supplying the particles 200 to be assembled to the liquid-gas interface 100, a continuous supply of raw materials is provided for continuous self-assembly; by continuously moving the substrate 3 through the liquid-gas interface 100, a continuous carrier supply is provided for continuous self-assembly. Thus, the smooth progress of continuous self-assembly is ensured from the three aspects of driving force, raw material supply, and carrier supply, so as to adapt to industrial applications.
[0058] In this embodiment, the substrate 3 further has a pickup surface for picking up the self-assembled structure; step S200 includes: continuously supplying a dispersion containing particles 200 to be assembled to the liquid-gas interface 100 on the side of the liquid-gas interface 100 facing the pickup surface of the substrate 3, wherein the flow field formed by the dispersion continuously pushes the self-assembled structure toward the pickup surface of the substrate 3 so that the self-assembled structure is continuously picked up by the pickup surface of the substrate 3.
[0059] Figure 2 The blue arrows in the diagram represent the flow direction of the dispersion. The dispersion is supplied to the liquid-gas interface 100 from the left to the right. The substrate 3 can be located on the right side of the liquid-gas interface 100, and the pickup surface of the substrate 3 faces left. Therefore, the flow field formed by the dispersion can drive the self-assembled structure to continuously move toward the pickup surface of the substrate 3, so that the self-assembled structure is continuously picked up by the pickup surface of the substrate 3.
[0060] This solution not only enables the continuous supply of particles 200 to be assembled to the liquid-gas interface 100, but also enables the self-assembled structure to be continuously picked up by the matrix 3 by the flow field formed by the dispersion liquid, thereby continuously transferring the self-assembled structure onto the matrix 3, which is very suitable for industrial applications.
[0061] For example, such as Figure 2 As shown, in this scheme, the flow directions of the two Marangoni flow fields at the liquid-gas interface 100 are a first direction D1 and a second direction D2, respectively, from the two heat sources 2 toward the reference plane P and perpendicular to the reference plane P, with the first direction D1 and the second direction D2 being opposite. The flow direction of the dispersion liquid flow field at the liquid-gas interface 100 is a third direction D3 toward the substrate 3, with the third direction D3 being perpendicular to the first direction D1 and the second direction D2. Therefore, in this scheme, the particles 200 to be assembled on the liquid-gas interface 100 are driven by the Marangoni flow fields of the first direction D1 and the second direction D2 to perform self-assembly, and are also driven by the dispersion liquid flow field of the third direction D3 to transfer to the substrate, realizing the simultaneous occurrence of the self-assembly process and the transfer process, greatly improving the self-assembly efficiency.
[0062] In this embodiment, further, in step S100, the temperature gradient is maintained by keeping the temperature of the heat source 2 constant and continuously cooling the liquid-gas interface 100, so that the temperature gradient and Marangoni flow field on the liquid-gas interface 100 exist for a long time.
[0063] For example, a controller can be used to control the heat source 2 to heat the liquid-gas interface 100 at a constant temperature using PID constant temperature control. Alternatively, a temperature sensor can be installed on the heat source 2, electrically connected to the controller. The temperature sensor collects the temperature of the heat source 2 and transmits the temperature data to the controller. The controller then controls the heating temperature of the heat source 2 based on this temperature data to maintain a constant temperature. Preferably, this constant temperature is lower than the boiling point of the liquid in the liquid pool 1.
[0064] For example, such as Figure 4 As shown, a cooling device can be arranged at the bottom of the liquid pool 1 to continuously cool the liquid in the liquid pool 1, so that the temperature of the liquid and the liquid-gas interface 100 in the liquid pool 1 is always lower than the temperature of the heat source 2, thereby ensuring that the temperature gradient on the liquid-gas interface 100 persists.
[0065] For example, the cooling device is a cooling pipe connected to a water pump. The water pump pumps cold water into the cooling pipe, where the cold water absorbs and removes heat from the liquid in the liquid pool 1, thus cooling the liquid in the pool 1. The cooling pipe can be made of materials with good thermal conductivity, such as metal, to improve heat exchange efficiency. After absorbing heat, the cold water in the cooling pipe becomes hot water. To achieve circulating cooling, a semiconductor cooling chip or similar method can be used to cool the hot water. The cooled water is then pumped back into the cooling pipe, thus achieving circulating cooling and ensuring a good cooling effect.
[0066] Figure 3 It also shows a diagram illustrating the cooling effect of arranging a cooling device within liquid pool 1. Figure 3 The blue component is a cooling device, which is located in the middle of the bottom of the liquid in the liquid pool 1. The center of the cooling device is located at the reference plane P to achieve symmetrical cooling of the liquid on both sides of the reference plane P.
[0067] However, this application is not limited to this. In other embodiments, the temperature gradient can also be maintained by controlling the heating plate to heat the liquid phase at an increasing temperature. However, this method consumes a lot of energy, and the temperature of the liquid in the liquid pool 1 will not continue to rise after reaching the boiling point. Therefore, it is difficult to maintain the temperature gradient for a long time by heating at an increasing temperature. Therefore, the inventors recommend maintaining the temperature gradient by cooling the liquid in the liquid pool 1.
[0068] In this embodiment, as Figure 4As shown, further, step S200 includes: supplying a dispersion containing particles 200 to be assembled to the liquid-gas interface 100 through the feeding panel 4, wherein the feeding panel 4 is inclined relative to the liquid-gas interface 100 and in contact with the liquid-gas interface 100, and the particles 200 to be assembled in the dispersion are pre-spread on the feeding panel 4 before entering the liquid-gas interface 100.
[0069] In this embodiment, the feeding panel 4 is used to supply the particles 200 to be assembled, so that the particles 200 to be assembled enter the liquid-gas interface 100 in a dispersed state, so as to facilitate the preparation of a single-layer self-assembled structure.
[0070] For example, such as Figure 4 As shown, the upper end of the feeding panel 4 is fixed to the side wall of the liquid pool 1. The length direction of the feeding panel 4 is perpendicular to the reference plane P. The lower end of the feeding panel 4 extends into the liquid in the liquid pool 1 and contacts the liquid-gas interface 100. The feeding panel 4 is tilted at a preset angle relative to the liquid-gas interface 100. Therefore, when the dispersion liquid containing the particles to be assembled 200 is supplied from the upper end of the feeding panel 4, the dispersion liquid flows downward along the surface of the feeding panel 4. At the same time, the particles to be assembled 200 in the dispersion liquid are pre-spread on the surface of the feeding panel 4, so as to reach the liquid-gas interface 100 in a dispersed state.
[0071] Furthermore, the upper end of the feeding panel 4 is provided with multiple feeding ports (not shown in the figure), the multiple feeding ports are arranged at equal intervals along the length direction of the feeding panel 4, and the multiple feeding ports are at the same height relative to the liquid-gas interface 100; step S200 includes: supplying a dispersion containing the particles to be assembled 200 through the multiple feeding ports simultaneously and at the same supply speed, so that the pre-spread particles to be assembled 200 have the same concentration and speed when entering the liquid-gas interface 100 below from different positions at the lower end of the feeding panel 4, which is beneficial to the continuous self-assembly.
[0072] For example, the liquid-gas interface 100 is the surface of water, that is, the liquid in the liquid pool 1 is deionized water; the particles to be assembled 200 are hydrophobic particles, for example, the material of the particles to be assembled 200 is hydrophobic materials such as polystyrene (PS), silicon dioxide (SiO2) or polytetrafluoroethylene (PTFE); the feeding panel 4 is a hydrophilic panel, for example, the material of the hydrophilic panel is quartz or metal, and the metals that can be selected include, but are not limited to, chromium, aluminum, zinc and their oxides; the liquid in the dispersion is deionized water or a hydrophilic liquid (e.g., ethanol).
[0073] In this embodiment, further, in step S300, the substrate 3 is a thin film, which can be wound around a rotating shaft. This rotating shaft can be located in the liquid pool 1 and below the liquid-gas interface 100. By lifting the film upwards, the film moves through the liquid-gas interface 100, and automatically picks up the self-assembly structure on the liquid-gas interface 100 when it passes through it. Furthermore, a rotatable roller can be provided outside the liquid pool 1 to lift the film and guide it to move in a preset direction outside the liquid pool 1, for example, to the next workstation. Exemplarily, the direction of film movement is the fourth direction D4, which can be parallel to the third direction D3.
[0074] Furthermore, in step S300, the intersection line of the thin film and the liquid-gas interface 100 is perpendicular to the reference plane P. This intersection line can pass through two heat sources 2, for example, the intersection line passes through the center of the two heat sources 2.
[0075] This disclosure utilizes temperature difference to construct a stable and long-lasting opposing Marangoni flow field, based on which the particles to be assembled 200 are continuously self-assembled. The resulting self-assembled structure is stable, with a large self-assembly area, high yield, high self-assembly efficiency, low requirements for environmental conditions, and simple self-assembly equipment, which can meet industrial needs.
[0076] An embodiment of the second aspect of this disclosure provides an apparatus for preparing self-assembled structures. Figure 4 A schematic diagram of an apparatus for preparing a self-assembled structure according to an embodiment of the present disclosure is shown.
[0077] like Figure 4 As shown, the device includes a liquid pool 1, two heat sources 2, a feeding device, and a substrate 3. The liquid pool 1 contains a liquid phase with a liquid-gas interface 100 exposed to a gaseous environment. The two heat sources 2 are arranged on the liquid-gas interface 100 and symmetrical with respect to a reference plane P perpendicular to the liquid-gas interface 100. A temperature gradient decreasing from the two heat sources 2 towards the reference plane P is established on the liquid-gas interface 100 by the two heat sources 2, generating two Marangoni flow fields flowing in opposite directions from the two heat sources 2 towards the reference plane P on the liquid-gas interface 100. The feeding device supplies particles 200 to be assembled to the liquid-gas interface 100. Under the action of the two Marangoni flow fields, the particles 200 aggregate towards the reference plane P and form densely packed self-assembled structures. The substrate 3 is used to pick up the self-assembled structures.
[0078] In some embodiments, such as Figure 4 As shown, the liquid pool 1 has two opposing sidewalls, and two heat sources 2 are fixed on the inner surfaces of the two sidewalls respectively. A part of each heat source 2 is located in the liquid phase, and the other part of each heat source 2 is located in the gas phase environment.
[0079] Furthermore, such as Figure 4As shown, the two heat sources 2 are two parallel heating plates.
[0080] In some embodiments, such as Figure 4 As shown, the feeding device is a feeding panel 4. The feeding panel 4 is inclined relative to the liquid-gas interface 100 and in contact with the liquid-gas interface 100. The upper end of the feeding panel 4 is provided with multiple feeding ports, and the lower end of the feeding panel 4 is in contact with the liquid-gas interface 100. The multiple feeding ports are arranged at equal intervals in a direction perpendicular to the reference plane P, and the multiple feeding ports are at the same height relative to the liquid-gas interface 100.
[0081] In some embodiments, such as Figure 4 As shown, the apparatus for preparing the self-assembled structure also includes a cooling device located in the liquid pool 1, which is used to continuously cool the liquid and liquid-gas interface 100 in the liquid pool 1 to maintain the temperature gradient.
[0082] In some embodiments, the substrate 3 is a thin film that continuously picks up self-assembled structures by continuously moving through the liquid-gas interface 100.
[0083] Furthermore, the intersection line of the thin film and the liquid-gas interface 100 is perpendicular to the reference plane P, and this intersection line can pass through the two heat sources 2, for example, the intersection line passes through the center of the two heat sources 2.
[0084] The apparatus for preparing a self-assembled structure according to the embodiments of this disclosure has the same principle and beneficial effects as the method for preparing a self-assembled structure according to the first aspect embodiment, and will not be described again here. Exemplary structural configurations of the apparatus for preparing a self-assembled structure according to the embodiments of this disclosure, such as the specific structural configurations of the heat source 2, cooling device, feeding panel 4, and substrate 3, have been described in the first aspect embodiment, and these contents are incorporated by reference to the second aspect embodiment, and will not be described again.
[0085] The above description is merely an embodiment of this specification and is not intended to limit this specification. Various modifications and variations can be made to this specification by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this specification should be included within the scope of the claims of this specification.
Claims
1. A method for preparing self-assembled structures, characterized in that, include: By arranging two heat sources on a liquid-gas interface and symmetrical about a reference plane perpendicular to the liquid-gas interface, a temperature gradient decreasing from the two heat sources toward the reference plane is established at the liquid-gas interface to generate two Marangoni flow fields flowing toward the reference plane from the two heat sources at the liquid-gas interface. Particles to be assembled are provided to the liquid-gas interface, and the particles to be assembled aggregate toward the reference surface under the action of the two Marangoni flow fields and form a densely arranged self-assembled structure. as well as The self-assembled structure is transferred onto the substrate.
2. The method for preparing a self-assembled structure according to claim 1, characterized in that, The method of establishing a temperature gradient at the liquid-gas interface by means of two heat sources arranged on a liquid-gas interface and symmetrical about a reference plane perpendicular to the liquid-gas interface, wherein the temperature decreases from the two heat sources toward the reference plane, includes: maintaining the temperature gradient by continuously increasing the temperature of the heat sources, or by keeping the temperature of the heat sources constant and continuously cooling the liquid-gas interface, so that the two Marangoni flow fields continue to exist. Providing the particles to be assembled to the liquid-gas interface includes: continuously supplying the particles to be assembled to the liquid-gas interface to continuously form the self-assembled structure; The step of transferring the self-assembled structure onto the substrate includes: continuously picking up the self-assembled structure by continuously moving the substrate through the liquid-gas interface.
3. The method for preparing a self-assembled structure according to claim 2, characterized in that, The liquid-gas interface is the liquid surface of the liquid phase; The continuous cooling of the liquid-gas interface includes: continuously cooling the liquid-gas interface by means of a cooling device arranged in the liquid phase.
4. The method for preparing a self-assembled structure according to claim 2, characterized in that, The substrate has a pickup surface for picking up the self-assembled structure; The step of providing the particles to be assembled to the liquid-gas interface includes: continuously supplying a dispersion containing the particles to be assembled to the liquid-gas interface on the side of the liquid-gas interface facing the pickup surface, wherein the flow field formed by the dispersion continuously pushes the self-assembled structure toward the pickup surface of the substrate, so that the self-assembled structure is continuously picked up by the pickup surface of the substrate.
5. The method for preparing a self-assembled structure according to claim 4, characterized in that, The flow directions of the two Marangoni flow fields at the liquid-gas interface are a first direction and a second direction, respectively, from the two heat sources toward the reference plane and perpendicular to the reference plane, wherein the first direction and the second direction are opposite; The flow field formed by the dispersion at the liquid-gas interface flows in a third direction toward the matrix, which is perpendicular to the first direction and the second direction.
6. The method for preparing a self-assembled structure according to claim 2, characterized in that, The substrate is a thin film, and the intersection line between the thin film and the liquid-gas interface is perpendicular to the reference plane.
7. The method for preparing a self-assembled structure according to any one of claims 1 to 6, characterized in that, The step of providing the particles to be assembled to the liquid-gas interface includes: supplying a dispersion containing the particles to be assembled to the liquid-gas interface through a feeding panel, wherein the feeding panel is inclined relative to and in contact with the liquid-gas interface, and the particles to be assembled in the dispersion are pre-spread on the feeding panel before entering the liquid-gas interface.
8. The method for preparing a self-assembled structure according to claim 7, characterized in that, The upper end of the feeding panel is provided with multiple feeding ports, the lower end of the feeding panel is in contact with the liquid-gas interface, the multiple feeding ports are arranged at equal intervals in a direction perpendicular to the reference plane, and the multiple feeding ports are at the same height relative to the liquid-gas interface. The provision of the particles to be assembled to the liquid-gas interface includes: simultaneously supplying a dispersion containing the particles to be assembled through multiple feed ports at the same supply rate.
9. The method for preparing a self-assembled structure according to claim 7, characterized in that, The liquid-gas interface is the surface of water; The particles to be assembled are hydrophobic particles; The feeding panel is a hydrophilic panel; and The dispersion is a liquid, either water or a hydrophilic liquid.
10. The method for preparing a self-assembled structure according to any one of claims 1 to 6, characterized in that, The liquid-gas interface is the liquid surface of the liquid phase. The two Marangoni flow fields converge at the reference surface and form two flow field vortices symmetrical to the reference surface in the liquid phase. The two flow field vortices are respectively located between the two heat sources and the reference surface.
11. An apparatus for fabricating self-assembled structures, characterized in that, include: A liquid pool containing a liquid phase having a liquid-gas interface exposed to a gaseous environment; Two heat sources are arranged on the liquid-gas interface and symmetrical about a reference plane perpendicular to the liquid-gas interface. The two heat sources establish a temperature gradient on the liquid-gas interface that decreases in temperature from the two heat sources toward the reference plane, so as to generate two Marangoni flow fields on the liquid-gas interface that flow from the two heat sources toward the reference plane. A feeding device is used to provide particles to be assembled to the liquid-gas interface, wherein the particles are aggregated toward the reference surface and form a densely packed self-assembled structure under the action of the two Marangoni flow fields; and The substrate is used to pick up the self-assembled structure.
12. The apparatus for preparing self-assembled structures according to claim 11, characterized in that, The liquid pool has two opposing sidewalls, and the two heat sources are respectively fixed on the inner surfaces of the two sidewalls. A portion of each heat source is located in the liquid phase, and the other portion of each heat source is located in the gas phase environment.
13. The apparatus for preparing a self-assembled structure according to claim 11, characterized in that, The feeding device is a feeding panel, which is inclined relative to and in contact with the liquid-gas interface. The upper end of the feeding panel is provided with a plurality of feeding ports, and the lower end of the feeding panel is in contact with the liquid-gas interface. The plurality of feeding ports are arranged at equal intervals in a direction perpendicular to the reference plane, and the plurality of feeding ports are at the same height relative to the liquid-gas interface.
14. The apparatus for preparing a self-assembled structure according to claim 11, characterized in that, Also includes: A cooling device, located within the liquid pool, is used to continuously cool the liquid and liquid-gas interface within the liquid pool to maintain the temperature gradient.
15. The apparatus for preparing a self-assembled structure according to claim 11, characterized in that, The substrate is a thin film, which continuously picks up the self-assembled structure by moving continuously through the liquid-gas interface.