A method for large-area lossless gas-liquid interface quantum dot self-assembly film transfer based on capillary climbing

Abstract

This invention relates to a method for large-area, non-destructive self-assembly of quantum dot films at the gas-liquid interface based on capillary climbing transfer. The method utilizes the capillary climbing force generated by the surface property difference between the subphase and the substrate. The method uses capillary climbing to drive the non-destructive transfer of quantum dot films from the gas-liquid interface to a solid substrate (target substrate). By controlling the surface tension difference and wettability between the subphase and the target substrate, the capillary climbing force enables the mild and large-area fabrication of quantum dot superlattice films. Compared with existing technologies, the method of this invention utilizes capillary force as the main driving force to achieve non-destructive, large-area, and self-correcting transfer of quantum dot films from the liquid surface to the substrate, ultimately obtaining quantum dot films (large-area quantum dot superlattice films) with superlattice properties, excellent electrical properties, and surface smoothness.

Description

Technical Field

[0001] This invention relates to the field of nanomaterial preparation technology, and in particular to a method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer. Background Technology

[0002] Quantum dots, as important semiconductor nanomaterials, exhibit great application potential in devices such as photodetectors, solar cells, and light-emitting diodes through their self-assembly into superlattice films. Obtaining large-area, defect-free, and highly ordered quantum dot superlattice films is key to realizing their high-performance applications.

[0003] Currently, common methods for transferring quantum dot films assembled at the gas-liquid interface to solid substrates mainly include film stretching and stamping. In film stretching, liquid surface fluctuations and meniscus instabilities during the stretching process can easily lead to film wrinkling and tearing, especially in large-area transfers. Stamping relies on mechanical extrusion of the film, which can easily introduce defects or even cause film breakage, and requires extremely high substrate surface flatness. Both methods struggle to achieve "self-healing" of the film during the transfer process, limiting the quality, uniformity, and mechanical strength of the prepared films, particularly for applications on complex or uneven substrates.

[0004] Therefore, there is an urgent need to develop a novel quantum dot thin film transfer method that is gentle, non-destructive, adaptable to different surfaces, and capable of spontaneously correcting assembly defects. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology by providing a method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer. This method is a way to prepare large-area, high-quality quantum dot superlattice films on solid substrates. The method utilizes capillary forces as the main driving force to achieve non-destructive, large-area, self-correcting transfer of quantum dot films from the liquid surface to the substrate, ultimately obtaining quantum dot films with superlattice properties, excellent electrical properties, and surface smoothness (i.e., large-area quantum dot superlattice films).

[0006] The objective of this invention can be achieved through the following technical solutions: This invention provides a method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer. The core of this method lies in utilizing the capillary climbing force generated by the surface property difference between the subphase and the substrate. The method uses capillary climbing to drive the non-destructive transfer of quantum dot films from the gas-liquid interface to a solid substrate (target substrate). By controlling the surface tension difference and wettability between the subphase and the target substrate, the capillary climbing force enables the mild, large-area fabrication of quantum dot superlattice films.

[0007] Furthermore, the method includes the following steps: 1) Prepare single-layer or multi-layer closely packed quantum dot films on a subphase surface, wherein the quantum dot films are located at a gas-liquid interface; 2) After hydrophilic treatment of the target substrate, it is slowly (at a speed of less than 0.5 cm / s) and steadily immersed into the subphase at a certain tilt angle, so that the edge (front) of the target substrate comes into contact with the quantum dot film on the gas-liquid interface (floating on the gas-liquid interface); 3) Climbing film formation process: By controlling the surface tension difference and wettability between the subphase and the target substrate, the quantum dot film is transferred completely and continuously from the gas-liquid interface to the surface of the target substrate using the generated capillary climbing force; 4) The target substrate (which is already covered with a thin film) is vertically pulled at a constant speed (a constant and slow speed) to dry and fix the quantum dot film, and finally a large-area quantum dot superlattice film (large-area, high-quality quantum dot superlattice film) is obtained on the target substrate.

[0008] Furthermore, in step 3), a non-equilibrium interfacial energy condition is created by precisely designing the surface tension of the subphase, the surface chemistry (hydrophilic / hydrophobic) of the target substrate, and the surface pressure of the quantum dot film itself. This condition spontaneously drives the subphase liquid to "climb" upwards along the hydrophilic substrate surface, while simultaneously gently and continuously "pulling" the quantum dot film floating on the interface to the substrate surface as a "skin." This capillary climbing process is dynamic and adaptive, capable of repairing minor defects that may appear at the transfer front through local rearrangement of quantum dot particles, achieving self-correction.

[0009] Furthermore, the climbing film-forming process in step 3 has self-correcting and self-repairing effects, and can repair defects in quantum dot films through capillary-induced quantum dot rearrangement during the transfer process, thereby enhancing the mechanical stiffness and interface order of the quantum dot films.

[0010] Furthermore, the subphase is selected from one or more solvents that do not dissolve quantum dots, such as dimethyl sulfoxide and ethylene glycol.

[0011] Further, in step 1), the quantum dot film is formed at the gas-liquid interface by Langmuir-Blodgett technique or drop-coating self-assembly technique, and compressed to obtain close packing (the quantum dot film will automatically compress a certain distance due to the adsorption effect of its crystal plane).

[0012] Furthermore, the Langmuir-Blodgett (LB) technique includes the following process: First, in a nitrogen atmosphere, a subphase is placed in a Langmuir-Blodgett tank. A quantum dot solution is dropped onto the surface of the subphase. By using a moving barrier to compress the quantum dot layer, the surface quantum dot density can be increased, thus preparing a quantum dot film on the surface of the subphase.

[0013] Further, in step 2), the tilt angle of the target substrate ranges from 5° to 90°, preferably from 15° to 60°.

[0014] Furthermore, in step 3), the generation of the capillary climbing force depends on the subphase surface tension γ. sub Target substrate surface energy γ substrate and the surface pressure π of quantum dot thin films film Coordinated regulation to satisfy γ substrate + π film > γ sub The conditions are designed to drive the quantum dot film to climb the spontaneous growth direction.

[0015] Furthermore, the target substrate is a solid substrate. The solid substrate can be a SiO2 / Si substrate, etc.

[0016] Furthermore, the conditions for the hydrophilic treatment include: 200~400W oxygen plasma etching (oxygen etching) for 100~500s.

[0017] Furthermore, the type of quantum dots in the quantum dot film is not limited, including but not limited to one or more of PbS quantum dots, PbSe quantum dots, CdSe quantum dots, CsPbBr3 quantum dots, and HgTe quantum dots.

[0018] Furthermore, the area of ​​the large-area quantum dot superlattice film is on the order of square millimeters to several square centimeters, and it has a superlattice structure.

[0019] Furthermore, the area of ​​the large-area quantum dot superlattice film is [1 mm]. 2 ~10cm 2 】

[0020] Furthermore, the surface roughness Rq of the large-area quantum dot superlattice thin film, as measured by atomic force microscopy, is <500 pm.

[0021] Furthermore, the conductivity of the large-area quantum dot superlattice thin film is > 1×10⁻⁶. -2 S / cm, carrier mobility > 10 cm 2 / (V·s).

[0022] Further, in step 4), the constant speed is 0.1~5 mm / min, preferably 0.5~1 mm / min.

[0023] Compared with the prior art, the present invention has the following technical advantages: 1. This invention provides a method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer. This method enables gentle and non-destructive transfer by utilizing capillary force rather than mechanical external force, thus avoiding the film damage and breakage problems caused by traditional methods and ensuring the integrity of the film.

[0024] 2. This invention provides a method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer, which has self-correction and self-repair capabilities. The capillary climbing process is a dynamic equilibrium process that can automatically repair local defects generated during the transfer process, obtain superlattice films with higher order, and enhance the mechanical stiffness of the film.

[0025] 3. This invention provides a method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer. This method is easy to achieve the preparation of large-area uniform thin films ranging from square millimeters to several square centimeters, and the process is stable and highly reproducible.

[0026] 4. This invention provides a method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer. It has no special restrictions on the type of quantum dots and is applicable to a variety of material systems. It has lower requirements for substrate flatness, wider adaptability, and strong universality.

[0027] 5. This invention provides a method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer. The prepared large-area quantum dot superlattice thin films exhibit excellent performance, possessing superlattice characteristics, extremely smooth surfaces (roughness <500 pm), and high electrical conductivity (>1×10⁻⁶). -2 S / cm) and high carrier mobility (>10 cm) 2 / (V·s)), which can meet the requirements of high-performance optoelectronic devices. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the capillary climbing and transfer process described in this invention, wherein (a), (b), and (c) are schematic diagrams from three different perspectives.

[0029] Figure 2 The images show an atomic force microscope comparison of films prepared by the conventional film transfer method (roughness Rq ≈ 3nm) and the method of the present invention (roughness Rq ≈ 350pm), wherein (a) is the method of Example 1 of the present invention, and (b) is the conventional film transfer method of Comparative Example 1.

[0030] Figure 3The results of atomic force microscopy tests on the thin films prepared in Example 1 are shown, where (a) is a single-layer quantum dot superlattice thin film with a thickness of about 4.5 nm, and (b) is a multilayer quantum dot superlattice thin film with a thickness of about 80 nm.

[0031] Figure 4 The transmission electron microscope image of the large-area quantum dot superlattice thin film prepared by the method of Example 1 of the present invention shows a long-range ordered superlattice structure.

[0032] Figure 5 Scanning electron microscope image of a large-area quantum dot superlattice thin film prepared by the method of Example 1 of the present invention, showing a large-scale dense thin film structure.

[0033] Figure 6 The conductivity and mobility are calculated based on the transfer characteristic curves of PbS quantum dot films at different temperatures, where (a) is conductivity and (b) is mobility. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Component models, material names, connection structures, control methods, algorithms, and other features not explicitly described in this technical solution are considered common technical features disclosed in the prior art.

[0035] This invention discloses a method for self-assembly of quantum dots on a gas-liquid phase surface based on a capillary climbing transfer strategy, belonging to the field of nanomaterial self-assembly and thin film preparation technology. The innovative aspect of this method is the lossless transfer of quantum dot films from the gas-liquid interface to a solid substrate driven by capillary climbing. By controlling the surface tension difference and wettability between the subphase and the substrate, the capillary climbing force is utilized to achieve the mild and large-area preparation of quantum dot superlattice films, resulting in large-area quantum dot superlattice films. The method includes steps such as the self-assembly formation of quantum dot superlattices on the subphase surface, substrate immersion and interface contact, capillary-driven film climbing transfer, and uniformly pulling the substrate away from the subphase. By optimizing surface tension and wettability, large-area, lossless quantum dot films with long-range ordered superlattice structures (large-area quantum dot superlattice films) with millimeter to centimeter scale are obtained. These films exhibit low surface roughness (AFM test Rq < 500 pm) and excellent electrical properties (conductivity > 1×10⁻⁶). -2 S / cm, mobility > 10 cm 2 / (V·s)). Compared with the prior art, the present invention overcomes the shortcomings of traditional film transfer and stamping transfer methods, which are prone to film breakage, defects, and difficulty in adapting to uneven surfaces. It provides a new scheme for the preparation of quantum dot thin films with self-correction, self-repair capabilities, strong controllability, and high reproducibility, which is suitable for high-performance optoelectronic devices.

[0036] Example 1 This embodiment provides a method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer, comprising the following steps: Taking PbS quantum dots as an example, firstly, in a nitrogen atmosphere, 2 mL of dimethyl sulfoxide (DMSO) subphase is placed in a 1.5 cm × 1.5 cm × 1.5 cm PTFE bath. Then, 1 μL of a 60 mg / mL PbS quantum dot n-octane solution is dropped onto the subphase surface, allowing for self-assembly to form a dense monolayer film (PbS thin film). A 285 nm SiO2 / Si substrate (silicon dioxide / silicon wafer substrate, purchased from Hefei Kejing Company) that has undergone oxygen etching at 300 W, 27 Pa, and 120 s hydrophilic treatment is immersed in the substrate at a 60° angle relative to the subphase plane at a speed of 0.5 cm / s, with the SiO2 side facing upwards, ensuring the edge of the SiO2 / Si substrate contacts the thin film. Figure 1 As shown, due to the hydrophilicity of the silicon wafer, an upward capillary climbing force is generated, transferring the PbS film completely onto the SiO2 surface of the SiO2 / Si substrate at a speed of 0.2 mm / min. The SiO2 / Si substrate with the PbS film attached is then pulled at a speed of 1 mm / min to ensure complete transfer of the film onto the substrate. After drying at 70°C, a large-area quantum dot superlattice film is obtained. The resulting large-area quantum dot superlattice film can reach an area of ​​1 cm². 2 With a thickness as low as ~0.4 μm -2 Defect density, such as Figure 2 As shown, compared to the typical quantum dot supercrystalline film transfer method (where the film is fabricated on the subphase and then directly retrieved from the subphase using a substrate), a film thickness of ~0.8 μm can be achieved. -2 Regarding defect density, the large-area quantum dot superlattice film prepared in this embodiment showed a significant reduction in defect density. However, the stamping-transfer sample (where the film was directly coated onto the substrate SiO2 after being deposited on the subphase) exhibited more pronounced defects, with more cracks, some reaching ~8 μm. -2 The level. For example... Figure 3 As shown, the root mean square roughness of the prepared large-area quantum dot superlattice film, measured by atomic force microscopy (AFM), is ~350 pm. Figure 4 As shown, transmission electron microscopy (TEM) confirmed that the prepared large-area quantum dot superlattice thin film possesses a simple cubic superlattice structure, such as... Figure 5 As shown, scanning electron microscopy (SEM) reveals that the prepared large-area quantum dot superlattice thin film possesses a wide range of dense film structures, such as... Figure 6 As shown in the figure, the transfer characteristic curve test shows that the conductivity of the prepared large-area quantum dot superlattice film reaches 3.24 × 10⁻⁶. -2 The S / cm (average value obtained from multiple sample tests) indicates a hole mobility (carrier mobility) of 13.37 cm⁻¹. 2 / (V·s) (average value obtained from multiple sample tests).

[0037] Tables 1 and 2 show the conductivity and mobility calculated from the transfer characteristic curves of PbS quantum dot films at different temperatures in Example 1. Sample numbers 1-5, 2-6, 3-7, and 4-8 represent multiple sample tests based on Example 1.

[0038] Table 1. Conductivity calculated from the transfer characteristic curves of PbS quantum dot films at different temperatures in Example 1.

[0039] Table 2. Mobility calculated from the transfer characteristic curves of PbS quantum dot films at different temperatures in Example 1.

[0040] Example 2 This embodiment is used to investigate the effects of stronger hydrophilicity and smaller tilt angle on transfer speed and film quality.

[0041] This embodiment provides a method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer, comprising the following steps: Taking PbS quantum dots as an example, 2 mL of DMSO subphase was placed in a 1.5 cm × 1.5 cm × 1.5 cm polytetrafluoroethylene tank under nitrogen atmosphere. 1 μL of a 60 mg / mL n-octane solution of PbS quantum dots was dropped onto the subphase surface, allowing for self-assembly to form a dense monolayer film (PbS thin film). A 285 nm SiO2 / Si substrate (silicon dioxide / silicon wafer substrate, purchased from Hefei Kejing Company) that had undergone oxygen etching at 300 W, 27 Pa, and 300 s (to obtain stronger hydrophilicity) was immersed at a tilt angle of 0.5 cm / s relative to the subphase plane of 30° (smaller than in Example 1), with the SiO2 side facing upwards. The enhanced hydrophilicity significantly increased the capillary climbing force, while the smaller tilt angle resulted in a smoother contact between the film and the SiO2 / Si substrate. Compared to Example 1, the film climbing speed was significantly improved, reaching approximately 0.5 mm / min, indicating that the stronger capillary force facilitated faster film acquisition. Due to the hydrophilicity of the silicon wafer, an upward capillary climbing force was generated, completely transferring the PbS film onto the SiO2 surface of the SiO2 / Si substrate. The SiO2 / Si substrate with the PbS film attached was then pulled at a speed of 1 mm / min and dried at 70°C to obtain a large-area quantum dot superlattice film. The obtained large-area quantum dot superlattice film can reach an area of ​​1 cm². 2 AFM measured its root mean square roughness to be ~400 pm and its defect density to be ~0.5 μm. -2TEM confirmed it to be a simple cubic superlattice structure with an electrical conductivity of 6.89 × 10⁻⁶. -2 S / cm, hole mobility increased to 14.63 cm 2 / (V·s), proving that the optimized parameters are beneficial to obtaining higher quality electrical transmission performance.

[0042] Example 3 This embodiment is used to explore the effects of different sub-relative transfer processes and to comprehensively verify the universality of the method.

[0043] This embodiment provides a method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer, comprising the following steps: Taking PbS quantum dots as an example, 2 mL of ethylene glycol (EG) was placed in a 1.5 cm × 1.5 cm × 1.5 cm polytetrafluoroethylene (PTFE) bath as a subphase in a nitrogen atmosphere (its surface tension is about 10% higher than that of DMSO, while its viscosity is about 8 times that of DMSO). 1 μL of a 60 mg / mL n-octane solution of PbS quantum dots was dropped onto the subphase surface, and a tight monolayer film (PbS thin film) was formed through self-assembly. A 285 nm SiO2 / Si substrate (silicon dioxide / silicon wafer substrate, purchased from Hefei Kejing Company) that had undergone 300 W oxygen etching, 27 Pa, and 120 s hydrophilic treatment was immersed at a 60° angle relative to the subphase plane at a speed of 0.5 cm / s, with the SiO2 side facing upwards. Due to the properties of EG, the capillary climb process was slower and gentler. Therefore, the pulling speed was adjusted to 0.5 mm / min, and drying was carried out at 70 °C to obtain a large-area quantum dot superlattice thin film. The resulting large-area quantum dot superlattice thin films can reach an area of ​​1 cm². 2 AFM measured its root mean square roughness to be ~430 pm and its defect density to be ~0.5 μm. -2 This indicates that even with a change in subphase, an extremely smooth thin film can still be obtained. TEM confirmed a simple cubic superlattice structure with an electrical conductivity of 5.92 × 10⁻⁶. -2 S / cm, hole mobility is 14.01cm 2 / (V·s). This embodiment successfully demonstrates that the capillary climbing method of the present invention has good adaptability to different subphase systems, and optimized control can be achieved by adjusting parameters such as the lifting speed.

[0044] Example 4 This embodiment is used to investigate the effects of increasing film thickness and changing quantum dot materials.

[0045] This embodiment provides a method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer, comprising the following steps: Taking HgTe quantum dots as an example, 2 mL of EG subphase was placed in a 1.5 cm × 1.5 cm × 1.5 cm PTFE bath under nitrogen atmosphere. 3 μL (more solution volume, same concentration, same size, to increase film thickness) of a 60 mg / mL HgTe quantum dot n-hexane solution was dropped onto the subphase surface, allowing for self-assembly to form a multilayer film (HgTe thin film). A 285 nm SiO2 / Si substrate (silicon dioxide / silicon wafer substrate, purchased from Hefei Kejing Company) that had undergone 300 W oxygen etching, 27 Pa, and 120 s hydrophilic treatment was slowly immersed at a 60° angle, with the SiO2 side facing upwards. The substrate was pulled up at a speed of 1 mm / min and dried at 70 °C to obtain a large-area quantum dot superlattice film. The obtained large-area quantum dot superlattice film can reach an area of ​​1 cm². 2 AFM showed a surface roughness of ~420 pm (slightly increased due to increased film thickness, but still atomically smooth). TEM confirmed its hexagonal close-packed (HCP) superlattice structure, consistent with the properties of HgTe quantum dots. Electrical tests showed a conductivity of 8.45 × 10⁻⁶. -2 S / cm, with an electron mobility as high as 21.20 cm⁻¹. 2 / (V·s) demonstrates the effectiveness of this method for preparing thin films of different materials and thicknesses, and shows that it can achieve high mobility.

[0046] Comparative Example 1 This comparative example provides a general quantum dot supercrystalline film transfer method, which is basically the same as that in Example 1. The difference is that in Example 1, a portion of the hydrophilically treated SiO2 / Si substrate is inserted into the subphase at a certain angle, and only a part of the substrate enters the subphase. The film is then allowed to slowly climb up the part that has not entered the subphase by relying on capillary force. In this comparative example, the film is extracted by completely immersing the SiO2 / Si substrate horizontally into the subphase, and then manually removing the film from the subphase from bottom to top.

[0047] Comparative Example 2 This comparative example provides a stamping transfer method, which is basically the same as that in Example 1, except that: in this comparative example, the bottom SiO2 surface of a 285nm SiO2 / Si substrate that has undergone hydrophilic treatment at 300W, 27Pa, and 120s is placed on the thin film to pick up the film. After contact is completed, the substrate is lifted upward away from the gas-liquid interface at a speed of 1 mm / min.

[0048] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer, characterized in that, Includes the following steps: 1) A quantum dot film is prepared on a subphase surface, wherein the quantum dot film is located at a gas-liquid interface; 2) After hydrophilic treatment of the target substrate, it is immersed in the subphase at a certain tilt angle and a speed of less than 0.5 cm / s, so that the edge of the target substrate contacts the quantum dot film on the gas-liquid interface; 3) Utilizing the generated capillary climbing force, the quantum dot film is transferred from the gas-liquid interface to the surface of the target substrate; 4) Pull the target substrate at a constant speed to complete the drying and fixation of the quantum dot film, and finally obtain a large area quantum dot superlattice film on the target substrate.

2. The method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer according to claim 1, characterized in that, The subphase is selected from one or more of dimethyl sulfoxide and ethylene glycol; In step 1), the quantum dot film is formed at the gas-liquid interface using the Langmuir-Blodget technique and compressed to obtain a close packing.

3. The method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer according to claim 2, characterized in that, The Langmuir-Blodget technique includes the following process: First, in a nitrogen atmosphere, a subphase is placed in a Langmuir-Blodgett tank, and a quantum dot solution is dropped onto the surface of the subphase to prepare a quantum dot film.

4. The method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer according to claim 1, characterized in that, In step 2), the tilt angle of the target substrate ranges from 5° to 90°.

5. The method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer according to claim 1, characterized in that, In step 3), the generation of the capillary climbing force depends on the subphase surface tension γ. sub Target substrate surface energy γ substrate and the surface pressure π of quantum dot thin films film Coordinated regulation to satisfy γ substrate +π film > γ sub The conditions are designed to drive the quantum dot film to climb the spontaneous growth direction.

6. The method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer according to claim 1, characterized in that, The conditions for the hydrophilic treatment include: 200~400W oxygen plasma etching for 100~500s.

7. The method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer according to claim 1, characterized in that, The quantum dot types of the quantum dot film include one or more of PbS quantum dots, PbSe quantum dots, CdSe quantum dots, CsPbBr3 quantum dots, and HgTe quantum dots.

8. The method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer according to claim 1, characterized in that, The large-area quantum dot superlattice film has an area ranging from square millimeters to several square centimeters and has a superlattice structure; The surface roughness Rq of the large-area quantum dot superlattice film is < 500 pm.

9. The method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer according to claim 1, characterized in that, The conductivity of the large-area quantum dot superlattice thin film is > 1×10⁻⁶. -2 S / cm, carrier mobility > 10 cm 2 / (V·s).

10. The method for large-area, non-destructive self-assembly of quantum dots at the gas-liquid interface based on capillary climbing transfer according to claim 1, characterized in that, In step 4), the constant speed is 0.1~5 mm / min.

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