Preparation method of short-range ordered rainbow-colored nanofilm with adjustable transparency

Abstract

A method for preparing a short-range ordered iridescent nanofilm with adjustable transparency comprises the following steps: Step 1: assembling metal nanoparticles at the interface of the two phases and transferring them to the desired substrate; Step 2: dispersing polystyrene spheres using n-butanol, assembling the short-range ordered structure on the water surface, and transferring the structure; Step 3: heating the sample above the glass transition temperature of the polystyrene and holding it for a period of time to cause the polystyrene to collapse, covering some of the metal nanoparticles; Step 4: cleaning the unprotected metal nanoparticles; Step 5: removing the polystyrene spheres, leaving the short-range ordered metal particle structure on the substrate. This method can produce an iridescent film with controllable color, adjustable transparency, and nanometer-scale thickness, and has important application prospects in fields such as anti-counterfeiting and exterior decoration.

Description

Technical Field

[0001] The invention belongs to the technical field of nano-manufacturing, and in particular relates to a method for preparing a short-range ordered rainbow-colored nano film with adjustable transparency. Background Art

[0002] In 1665, Newton first used a prism to separate white light into seven colors, allowing people to witness the first artificial "rainbow" and sparking a quest for the true nature of color. Over the centuries, scientists have developed a deep understanding of the causes of color in plants and animals. Color can be generated by energy band transitions of electrons within dye molecules (such as anthocyanins and chlorophyll). Furthermore, the presence of micro- and nanostructures within the feathers of certain birds and wings of butterflies allows light to interfere, diffract, and scatter, producing color. This type of color is collectively referred to as structural color. Currently, most structural colors in nature are believed to be generated by five basic optical processes or their combinations: thin-film interference, multilayer interference, diffraction grating effects, photonic crystals, and light scattering. With the advancement of micro- and nanofabrication technologies, a variety of artificial structural color schemes have been proposed, including dielectric photonic crystal structures, surface plasmon colloidal nanostructures, and metal-dielectric-metal sandwich structures. Compared with traditional dyes, the structural colors of artificial micro-nano structures have multiple advantages such as ultra-high resolution, ultra-thin thickness (submicron level), ultra-light weight, long-term stability, and low toxicity, and have received widespread attention and research.

[0003] As research deepens, many scholars and designers are considering the mechanisms that create a dazzling appearance by manipulating microscopic arrangements. In 2023, researchers proposed an explanatory, intuitive, and accurate modal-based tool, the BRDF model, which reveals the key physical mechanisms and characteristics, theoretically studying the origin of the dazzling appearance. This mathematical model can be used to describe light reflection properties. This multidimensional radiation function describes how the metasurface scatters all possible plane waves, taking into account the angle of incident light, the angle of outgoing light, and the wavelength of light. It has been found that colloidal crystals are crystalline structures composed of nanostructures with a predetermined order and periodicity. Due to the micro-nanoscale, ordered particle arrangement, and material properties, they produce unique optical phenomena and create the conditions for photonic crystals and structural color. Colloidal self-assembly is a simple and effective method for constructing colloidal crystal structures. However, traditional self-assembly methods are not only time-consuming but also produce colloidal crystals with a very small area. It has been discovered that by creating a stable, continuous liquid-air interfacial tension gradient, the resulting Marangoni effect can drive nanoparticles to acquire nearly 50 kT of kinetic energy in a short period of time, instantly overcoming the free energy barrier between particles (formed by electrostatic repulsion, typically several kT) and forming highly ordered colloidal crystals. Thanks to the long-range surface tension gradient, the fabrication area of ​​colloidal crystal films has been demonstrated to exceed an astonishing 1000 square centimeters without compromising their quality, demonstrating enormous potential for large-scale manufacturing. Particles of various sizes, materials, and functions can form tightly packed self-assembled monolayers and be transferred to various substrates without damage, demonstrating tremendous versatility.

[0004] Currently, demand for personalized, colorful appearances is growing. Using nanostructures as basic units, nanostructured metasurfaces can achieve appearances unattainable with traditional materials, such as the ability to individually control halos and colors. In a 2022 paper published in Nature Materials, Philippe Lalanne et al. from the University of Lyon, France, further expanded on the concept of structural color in nanomaterials, proposing the concept of "visual appearance" of nanomaterials. They emphasized that specular and diffuse reflection components, light sources, and detection locations all influence human perception, and theoretically predicted the existence of unique phenomena such as "diffuse iridescence" and "diffuse halos" in disordered metasurface structures, which do not exist in nature. They also predicted that colloidal nanostructures could potentially enable large-scale fabrication of colorful structures, pointing to a new direction in the research of colorful effects in micro- and nanostructures. Against this backdrop, in 2023, a team from Southeast University used a multiscale pattern transfer process using colloidal nanostructures to create colorful patterns. They also studied how the appearance of patterns in long-range ordered structures changes under different light source excitation and observation angles.

[0005] Compared to long-range ordered nanostructures, short-range ordered nanostructures can achieve rainbow color distribution across a wide viewing angle. However, the fabrication of short-range ordered nanostructures currently relies on self-assembled stacking of nanostructures, resulting in thicknesses of hundreds of microns. This makes rainbow color distribution difficult to control and is also opaque. The challenge of constructing short-range ordered structures over large areas while achieving nanoscale thickness, adjustable transparency, and a colorful appearance remains unresolved. Summary of the Invention

[0006] Technical problem: The purpose of the present invention is to provide a method for preparing a short-range ordered rainbow-colored nanofilm with adjustable transparency, to solve the problem of how to design to achieve rainbow-colored structure at the nanoscale, and to solve the problem of simultaneously achieving controllable nanostructure, adjustable transparency and controllable color appearance.

[0007] Technical solution: The method for preparing a short-range ordered rainbow nanofilm with adjustable transparency of the present invention specifically comprises the following steps:

[0008] Step 1: Assembly and transfer of metal nanoparticles at the two-phase interface: The metal nanoparticles are self-assembled into a dense monolayer at the gas-liquid or liquid-liquid interface and transferred to the desired substrate;

[0009] Step 2: Short-range ordered assembly and transfer of polystyrene spheres at the water-air interface: The first polystyrene spheres are dispersed in n-butanol, and the first polystyrene sphere solution dispersed in n-butanol is added dropwise to the water-air interface. The first polystyrene spheres on the interface are distributed in a short-range order by utilizing the Marangoni effect and the interaction force between particles. Close-packed metal nanoparticles are placed parallel to the liquid surface assembled with the polystyrene microspheres and pressed downward to form a short-range ordered structure of the first polystyrene spheres, which are then transferred to the substrate with the metal nanoparticles, thereby obtaining a first polystyrene sphere-metal nanoparticle composite structure.

[0010] Step 3: Thermally induced collapse of the second polystyrene spheres: The first polystyrene sphere-metal nanoparticle composite structure is heated to 115-130 degrees Celsius and maintained at this temperature for more than 10 seconds, causing the first polystyrene spheres to connect and collapse, forming second polystyrene spheres that cover a portion of the metal nanoparticles.

[0011] Step 4: Cleaning the metal nanoparticles not protected by the second polystyrene balls: using ultrapure water or ultrasonic cleaning to remove the metal nanoparticles on the substrate that are not covered by the second polystyrene balls;

[0012] Step 5: Removal of the second polystyrene spheres: The second polystyrene spheres are removed by washing with an organic solvent, dry etching, or heating, thereby leaving short-range ordered transparent metal nanoparticles on the substrate, thereby showing a rainbow appearance.

[0013] The metal nanoparticles include gold, silver, platinum, copper, aluminum, palladium or alloy materials composed of two or more thereof, and the size of the nanoparticles is 5 to 100 nanometers.

[0014] The assembly method of the metal nanoparticles is:

[0015] Method 1: The prepared metal nanoparticles are placed in a glass bottle, and then ethanol / n-hexane is used as a solvent to prepare a perfluorodecanethiol dispersion, which is then poured into the metal nanoparticles and shaken to obtain a metal nanoparticle monolayer film after stabilization.

[0016] Method 2: First, toluene containing oleylamine is added to a citric acid-stabilized aqueous solution of metal nanoparticles, and the mixture is shaken vigorously to form a two-phase mixture. After standing, the aqueous phase is discarded to obtain a toluene oil phase containing metal nanoparticles; the toluene phase is mixed with ultrapure water, stirred at high speed to form a mixture, and after standing, the toluene phase containing metal nanoparticles is collected by a one-time washing; next, the toluene phase is washed with water to obtain oleylamine-coated metal nanoparticles; toluene / diethylene glycol is added to a clean container, and the toluene phase containing oleylamine-coated metal nanoparticles is spread on the surface of the toluene / diethylene glycol, the container is covered with a glass slide, and the toluene is slowly evaporated to allow the oleylamine-coated metal nanoparticles to self-assemble; after the toluene is evaporated, a self-assembled monolayer film of oleylamine-coated metal nanoparticles is formed on the surface of the toluene / diethylene glycol.

[0017] The substrate is made of aluminum oxide, quartz, glass, or indium tin oxide-coated glass.

[0018] The short-range ordered structure of the first polystyrene spheres at the subwavelength scale is achieved by adjusting the size of the first polystyrene spheres and the mass percentage of the first polystyrene spheres and n-butanol to achieve a short-range ordered structure at the water-air two-phase interface. The size of the first polystyrene spheres is 300 nanometers to 5 microns.

[0019] The method for removing the second polystyrene balls includes organic solvent washing, heating, oxygen plasma etching, inductive coupling, plasma etching or reactive ion etching.

[0020] The organic solvent is acetone, toluene or chloroform.

[0021] When the second polystyrene ball is removed by heating, the heating temperature is 600 to 1500 degrees and the time is 10 minutes to 5 hours.

[0022] The peak q wave vector q of the technical indicator structure factor S(q) of the short-range ordered distribution || Between 0.2 / micron and 25 / micron, here where q = k i-k s ,k i is the incident light wave vector, k s is the scattered light wave vector, N is the total number of the first polystyrene balls, r i , r j are the position vectors of the center of the first polystyrene ball i and j, respectively, || is the q-wave vector parallel to the water-air interface.

[0023] The mass percentage of the first polystyrene balls and n-butanol is 0.1 wt % to 20 wt %.

[0024] Beneficial effects: Compared with the existing technology, the present invention has the following advantages:

[0025] 1. The processing method of the rainbow-colored structure of short-range ordered transparent metal nanoparticles proposed in the present invention utilizes the collapse of polystyrene to cover and protect part of the metal nanoparticles. The short-range disordered structure of the gold nanoparticles can be controlled by controlling the concentration of polystyrene balls, thereby achieving adjustable transparency and controllable color appearance.

[0026] 2. Compared with traditional bottom-up and top-down self-assembly technologies, the processing method of short-range ordered transparent metal nanoparticle rainbow color structure proposed in the present invention does not require complex instruments and can achieve spacing control that cannot be achieved by ordinary self-assembly methods, thereby realizing short-range ordered structure and producing a unique rainbow color appearance.

[0027] 3. The nano-manufacturing technology proposed in the present invention has low manufacturing process cost, simple and convenient operation, economical use of instruments and materials, and is easy to mass-produce and put into application. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic flow chart of the processing method of transparent short-range ordered rainbow color structure.

[0029] The figure includes: substrate 1, metal nanoparticles 2, first polystyrene balls 3, liquid surface 4 assembled with polystyrene microspheres, and second polystyrene balls 5. DETAILED DESCRIPTION

[0030] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0031] The present invention proposes a method for preparing a short-range ordered rainbow-colored nanofilm with adjustable transparency. The specific principle of achieving a nanoscale film with controllable colorful appearance is as follows:

[0032] To achieve iridescence with short-range ordered structures, it is necessary to construct a nanostructured distribution with wavelength-scale spacing. This study selected wavelength-scale polystyrene nanospheres as the carrier for achieving this wavelength-scale spacing. Short-range order is achieved through the Marangoni effect, electrostatic repulsion, and initial non-uniform drop rate of the polystyrene nanospheres on the water surface. The source of this short-range order stems from the size constraints of the polystyrene nanospheres themselves and the control of the maximum spacing between particles. Furthermore, the varying initial velocities of the nanospheres dispersed in n-butanol at low addition to the water surface cause their randomized motion, resulting in long-range order. The self-assembly of the wavelength-scale polystyrene nanospheres on the liquid surface ensures this short-range order.

[0033] Since the transparency of the nanofilm is related to the concentration of metal nanoparticles, and also to factors such as the spacing and shape between the nanoparticles, the density of the metal nanoparticles formed on the substrate can be controlled by controlling the concentration of the polystyrene template. The greater the density of the metal nanoparticles, the smaller the brightness of the transparent film, and the smaller the density of the metal nanoparticles, the greater the brightness of the transparent film, thereby achieving local control of the transparency of the film. Since the spacing between the metal nanoparticles also meets the spacing of the wavelength order, it has a strong diffraction effect on light waves, thus having a rainbow appearance. The processing method of the short-range ordered transparent gold nanoparticle rainbow structure proposed by the present invention can be used to prepare a rainbow film with controllable color appearance, adjustable transparency, and nanometer-level thickness.

[0034] The present invention proposes a method for preparing a short-range ordered iridescent nanofilm with adjustable transparency, specifically comprising the following steps: Step 1: Assembly and transfer of metal nanoparticles at the two-phase interface, wherein the metal nanoparticles 2 are densely self-assembled into a monolayer at the gas-liquid or liquid-liquid interface and transferred to the desired substrate 1. Step 2: Short-range ordered assembly and transfer of polystyrene spheres at the water-air interface, wherein a certain concentration of polystyrene spheres is dispersed in n-butanol and dropwise added to the water-air interface. The Marangoni effect and inter-particle interaction force are utilized to make the polystyrene spheres on the interface exhibit short-range ordered distribution, and the peak q wave vector q of the short-range ordered distribution technical indicator structure factor S(q) is 100%. ||Located between 0.2 / micron and 25 / micron. The sample with densely packed metal nanoparticles 2 is placed parallel to the liquid surface 4 assembled with polystyrene microspheres, and pressed downward so that the first polystyrene balls (3) form a short-range ordered structure and then transferred to the substrate 1 with metal nanoparticles 2. The third step: thermal collapse of the first polystyrene balls 3. The above sample is heated to 115-130 degrees Celsius. At this temperature, it is maintained for a certain period of time. The first polystyrene balls 3 will collapse and then cover part of the metal nanoparticles 2. The fourth step: cleaning the metal nanoparticles not protected by the polystyrene balls. Use ultrapure water to clean or combine ultrasonic methods to remove the metal nanoparticles on the substrate that are not covered by polystyrene. The fifth step: removal of the second polystyrene balls 5. Use organic solvent washing, dry etching or heating to remove the polystyrene template, thereby leaving a short-range ordered transparent metal nanoparticle structure on the substrate, thereby showing a rainbow appearance.

[0035] The materials and nanomaterial processing technology selected for the processing method of the short-range ordered transparent gold nanoparticle rainbow structure proposed in the present invention include: the metal nanoparticles assembled at the two-phase interface are gold, silver, platinum, copper, aluminum, palladium or alloy materials composed of two or more of them, the size of the 3-nanometer particles is 5 to 500 nanometers, the gas-liquid interface may include air-water, air-ethylene glycol, air-ethylene glycol, the liquid-liquid interface includes n-hexane-water, toluene-water, and the substrate material may include aluminum oxide, quartz, glass sheet, glass sheet coated with indium tin oxide, etc.

[0036] The present invention proposes a method for processing short-range ordered transparent gold nanoparticles with iridescent structures to partially remove a polystyrene sphere template, comprising organic solvent rinsing, heating, inductively coupled plasma etching, and reactive ion etching. The organic solvent may be acetone, toluene, or chloroform. When removing the polystyrene spheres by heating, the heating temperature is 600 to 1500°C for a period of 10 minutes to 5 hours.

[0037] The present invention proposes a method for producing iridescent structures of short-range ordered transparent gold nanoparticles. The methods for achieving this are diverse, and therefore, the specific implementation and operation procedures vary depending on the preparation process and material properties. All of the following examples are based on the technical solutions of the present invention, but the scope of protection of the present invention is not limited to the following examples.

[0038] Example 1:

[0039] Self-assembled polystyrene nanoparticles were prepared at the air-water interface, and the short-range ordered rainbow color structure processing method proposed by the present invention was applied. The specific preparation process steps are as follows: Figure 1 As shown:

[0040] Step 1: Self-assemble gold nanoparticles into a dense monolayer at the air-liquid interface. Place 5 mL of freshly prepared gold nanocolloid into a glass vial. Then, pour 10 mL of perfluorodecanethiol solution (10 mmol / L, ethanol:n-hexane = 2:1) into the gold nanoparticle solution and shake for 3 seconds. Once stabilized, a gold nanoparticle monolayer is obtained. This densely packed monolayer is then transferred to the desired substrate 1.

[0041] Step 2: Through the self-assembly process, the first polystyrene balls 3 with a mass percentage of 2.5wt% (which can achieve the control of transparency and rainbow color distribution) are distributed in a short-range orderly manner on the liquid surface 4 of the water-air assembled polystyrene microspheres, wherein the size of the first polystyrene balls 3 is 600 nanometers. At this time, the peak q wave vector of the structure factor q || About 12 / micron.

[0042] Step 3: Place the substrate 1 adsorbed with gold nanoparticles parallel to the liquid surface 4 assembled with polystyrene microspheres, and press downward so that the first polystyrene balls 3 form a short-range ordered structure and then transfer it to the substrate 1 with metal nanoparticles 2 to obtain a first polystyrene ball-metal nanoparticle composite structure.

[0043] Step 4: Heating the first polystyrene ball-metal nanoparticle composite structure to 120 degrees Celsius and maintaining this temperature for 1 minute allows the first polystyrene balls to connect with each other and collapse, forming second polystyrene balls 5, which in turn cover a portion of the metal nanoparticles 2;

[0044] Step 5: Use ultrapure water to wash or combine with ultrasonic method to remove the gold nanoparticles not covered by polystyrene, and the remaining gold nanoparticles covered by the second polystyrene ball 5.

[0045] Step 6: Rinse with organic solvent to remove the polystyrene template and obtain gold nanoparticles distributed in a controllable short-range order.

[0046] The assembly method of the metal nanoparticles is:

[0047] Method 1: 5 to 10 ml of the prepared metal nanoparticles are placed in a glass bottle. Then, a 10 to 20 ml perfluorodecanethiol dispersion having a concentration of 10 mmol / L is prepared using ethanol / n-hexane with a volume ratio of 2:1 as a solvent. The dispersion is poured into the metal nanoparticles and shaken for 3 to 5 seconds. After stabilization, a metal nanoparticle monolayer film is obtained.

[0048] Method 2: First, 1 to 5 ml of toluene containing 1 mmol / L oleylamine is added to 5 to 10 ml of a citric acid-stabilized aqueous solution of metal nanoparticles, and the mixture is shaken vigorously to form a two-phase mixture. After standing, the aqueous phase is discarded to obtain a toluene-oil phase containing metal nanoparticles; the toluene phase is mixed with ultrapure water in a volume ratio of 5:1, stirred at high speed for 3 to 5 minutes to form a mixture, and allowed to stand for 3 to 5 hours; then, the toluene phase containing metal nanoparticles is collected by a one-time washing; next, the toluene phase is washed with water 3 to 5 times to obtain oleylamine-coated metal nanoparticles; 15 to 20 ml of toluene / diethylene glycol is added to a clean container, the toluene phase containing oleylamine-coated metal nanoparticles is spread on the surface of the toluene / diethylene glycol, the container is covered with a glass slide, and the toluene is slowly evaporated to allow the oleylamine-coated metal nanoparticles to self-assemble; after 180 to 250 minutes, the toluene is completely evaporated, and a self-assembled monolayer film of oleylamine-coated metal nanoparticles is formed on the surface of the toluene / diethylene glycol.

Claims

1. A method for preparing a short-range ordered rainbow-colored nanofilm with adjustable transparency, characterized in that The specific steps include: Step 1: Assembly and transfer of metal nanoparticles at the two-phase interface: The metal nanoparticles (2) are self-assembled into a dense monolayer at the gas-liquid or liquid-liquid interface and transferred to the desired substrate (1); Step 2: Short-range ordered assembly and transfer of polystyrene balls at the water-air interface: first polystyrene balls (3) are dispersed in n-butanol, and the solution of the first polystyrene balls (3) dispersed in n-butanol is added dropwise onto the water-air interface. The Marangoni effect and the interaction force between particles are used to make the first polystyrene balls (3) at the interface present a short-range ordered distribution. The substrate (1) with the closely packed metal nanoparticles (2) is placed parallel to the liquid surface (4) on which the polystyrene microspheres are assembled, and pressed downward, so that the first polystyrene balls (3) form a short-range ordered structure and are then transferred onto the substrate (1) with the metal nanoparticles (2), thereby obtaining a first polystyrene ball-metal nanoparticle composite structure. Step 3: Thermal collapse of the second polystyrene balls (5): heating the first polystyrene ball-metal nanoparticle composite structure to 115-130 degrees Celsius and maintaining the temperature for more than 10 seconds, so that the first polystyrene balls connect with each other and collapse, thereby obtaining the second polystyrene balls (5), which in turn cover part of the metal nanoparticles (2); Step 4: Cleaning the metal nanoparticles not protected by the second polystyrene balls: using ultrapure water cleaning or ultrapure water cleaning combined with ultrasonic method to remove the metal nanoparticles (2) on the substrate (1) that are not covered by the second polystyrene balls (5); Step 5: Removal of the second polystyrene balls (5): The second polystyrene balls (5) are removed by washing with an organic solvent, dry etching or heating, thereby leaving short-range ordered transparent metal nanoparticles (2) on the substrate (1), thereby exhibiting a rainbow appearance; The assembly method of the metal nanoparticles (2) is: Method 1: The prepared metal nanoparticles (2) are placed in a glass bottle, and then ethanol / n-hexane is used as a solvent to prepare a perfluorodecanethiol dispersion, and the dispersion is poured into the metal nanoparticles (2), shaken, and a metal nanoparticle monolayer film is obtained after stabilization; Method 2: First, toluene containing oleylamine is added to a citric acid-stabilized aqueous solution of metal nanoparticles, and the mixture is shaken vigorously to form a two-phase mixture. After standing, the aqueous phase is discarded to obtain a toluene phase oil phase containing metal nanoparticles; the toluene phase is mixed with ultrapure water, stirred at high speed to form a mixture, and after standing, the toluene phase containing metal nanoparticles is collected by a one-time washing; next, the toluene phase is washed with water to obtain oleylamine-coated metal nanoparticles (2); toluene / diethylene glycol is added to a clean container, and the toluene phase containing oleylamine-coated metal nanoparticles (2) is spread on the surface of the toluene / diethylene glycol, and the container is covered with a glass slide, and the toluene is slowly evaporated to allow the oleylamine-coated metal nanoparticles (2) to self-assemble; after the toluene is evaporated, a self-assembled monolayer film of oleylamine-coated metal nanoparticles (2) is formed on the surface of the toluene / diethylene glycol.

2. The method for preparing a short-range ordered rainbow nanofilm with adjustable transparency according to claim 1, characterized in that The metal nanoparticles (2) include gold, silver, platinum, copper, aluminum, palladium or alloy materials composed of two or more thereof, and the size of the nanoparticles is 5 to 100 nanometers.

3. The method for preparing a short-range ordered rainbow color nanofilm with adjustable transparency according to claim 1, characterized in that The material of the substrate (1) includes aluminum oxide, quartz, glass sheet or glass sheet coated with indium tin oxide.

4. The method for preparing a short-range ordered rainbow color nanofilm with adjustable transparency according to claim 1, characterized in that The first polystyrene spheres (3) are designed to achieve a short-range ordered structure at a subwavelength scale, i.e., the size of the first polystyrene spheres (3) and the mass percentage of the first polystyrene spheres (3) and n-butanol are adjusted to achieve a short-range ordered structure at the water-air two-phase interface. The size of the first polystyrene spheres (3) is 300 nanometers to 5 micrometers.

5. The method for preparing a short-range ordered iridescent nanofilm with adjustable transparency according to claim 1, characterized in that The method for removing the second polystyrene balls (5) includes organic solvent washing, heating, oxygen plasma etching, inductive coupling, plasma etching or reactive ion etching.

6. The method for preparing a short-range ordered rainbow colored nanofilm with adjustable transparency according to claim 5, characterized in that The organic solvent is acetone, toluene or chloroform.

7. The method for preparing a short-range ordered rainbow nanofilm with adjustable transparency according to claim 5, characterized in that When the second polystyrene balls (5) are removed by heating, the heating temperature is 600 to 1500 degrees Celsius and the time is 10 minutes to 5 hours.

8. The method for preparing a short-range ordered rainbow nanofilm with adjustable transparency according to claim 1, characterized in that The peak q wave vector q of the technical indicator structure factor S(q) of the short-range ordered distribution || Between 0.2 / micron and 25 / micron, here where q = k i -k s ,k i is the incident light wave vector, k s is the scattered light wave vector, N is the total number of the first polystyrene balls (3), r i , r j are the position vectors of the center of the i-th and j-th first polystyrene balls (3), q || is the q-wave vector parallel to the water-air interface.

9. The method for preparing a short-range ordered rainbow nanofilm with adjustable transparency according to claim 1, characterized in that The mass percentage of the first polystyrene balls and n-butanol is 0.1 wt % to 20 wt %.

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