Textured film and its manufacturing method

Abstract

The present invention relates to a thermoelectric textured film that exhibits electrical and thermal conductivity, and a method for producing the textured film. The textured film obtained by this method exhibits electrical and thermal conductivity, as well as high resistance to high temperatures and oxidation, and therefore these films can be used in many fields, such as electrical circuits, thermal barriers, thermoelectric applications, and lighting.

Description

[Technical Field]

[0001] Technical Field The present invention relates to a textured thermoelectric film that exhibits electrical and thermal conductivity, and a method for making the textured film. [Background technology]

[0002] Conventional technology In the current state of the art, textured materials are increasingly being used to manufacture products for applications where the transport of heat and / or charge carriers needs to be anisotropically restricted or promoted. In particular, ceramic textured materials are ideal for manufacturing products with heat resistance, chemical resistance, and insulating properties. Therefore, it is important to develop the field of use of textured materials, especially ceramics. In recent years, ceramic and non-ceramic films have been developed for this purpose.

[0003] The developed films can be used in electrical circuits, heat shields, electrocatalytic applications, electrochemical energy storage, high temperature electronic circuits and thermoelectric applications.

[0004] Canadian Patent Application No. CA2213209C discloses a ceramic film and a method for its manufacture. The method for producing a polycrystalline ceramic film on a substrate comprises the following steps: a sol-gel solution is mixed with a 5% to about 90% by weight solution of the ceramic powder to produce a uniform and stable dispersion; the resulting slurry or paint can be spin-coated, dip-coated, sprayed, or painted onto a planar or other substrate and fired to remove organic matter and develop a microcrystalline structure; the fired film is then heated; and a composite film is obtained.

[0005] Japanese Patent Publication No. JP3554523B2 discloses a method for producing ceramic films from a liquid slurry containing ceramic powder dispersed in a solvent. The liquid slurry containing the dispersed ceramic powder is first dried to prepare a precursor, which is then fired to form a so-called body-in-white. The precursor, bound with a polymer binder, is converted into a polycrystalline ceramic by firing and sintering. The polymer used in the dispersion is thermally decomposed during the heat treatment process and released in the form of vapor or gas. This method involves coating the liquid slurry onto a substrate to a uniform thickness and drying the coated substrate. The resulting liquid slurry on the coated substrate is then passed through a tunnel dryer to evaporate the solvent. This results in a polymer film containing a very high content of ceramic powder filler.

[0006] "Electrochemical investigations of Na 0.7 CoO2 cathode with PEO-NaTFSI-BMIMTFSI electrolyte as a promising material for Na-rechargeable battery 0.7 The paper, titled "Electrochemical Study of CoO2 Cathode," 0.7 It is disclosed that the CoO2 material is synthesized using a solid-state reaction method.

[0007] European patent document EP2975659A1 mentions thermoelectric ceramic materials. The ceramic materials described can be synthesized by conventional solid-state reaction methods. The ceramic materials have the formula (Ca) where 0.1≦x≦2.9 and 0<δ≦2. 3-x Na x )Co4O 9-δIn another embodiment, the mixed powder is obtained by mixing calcium carbonate, sodium carbonate, cobalt oxide raw materials, or other types of compounds containing these elements, such as oxides, hydroxides, bicarbonates, and nitrides. After drying, the powder is calcined in air at a temperature ranging from 800°C to 920°C for 2 to 24 hours to obtain the desired crystalline structure.

[0008] Korean Patent Publication No. KR20100099380A discloses forming a ceramic layer for adhesion and insulation between a metal substrate and a conductive layer. The ceramic layer is formed by applying ceramic powder to the upper surface of the substrate. A thermoelectric resin layer contains ceramic powder on the upper surface of the ceramic layer. A metal layer is formed on the upper surface of the thermoelectric resin layer using a sputtering method.

[0009] US Patent Publication US20070039641A1 describes thermoelectric cobalt oxide compounds and their use in heat management and power generation. The cobalt oxide film is preferably layered. In a preferred embodiment, the layer has the formula Co 1-y T y O2, where T represents a combination of one or more metal atoms selected from the transition metal group or the rare earth metal group. The thermoelectric cobalt oxide film can have a composition represented by the formula A x Co 1-y T y It has already been described that the composition is represented by the formula O2, where A represents a combination of one or more metal atoms selected from the alkali metal group, alkaline earth metal group, main group metal group, transition metal group, or rare earth metal group.

[0010] Chinese patent document CN104890325A describes a thermoelectric material or protective coating for a thermoelectric device, which comprises a glass surface layer containing a surface of a thermoelectric material and a ceramic composite substrate.

[0011] International Patent Publication WO2013191939A1 describes a method for forming an article. The method can include providing a substrate including a surface. The disclosure relates to a method for patterning a carbon coating and an article having such a patterned carbon coating. The invention includes the following steps: (a) providing a substrate including a surface; (b) forming a solvent-soluble layer in a pattern on or over the surface of the substrate; (c) forming a second layer; and (d) removing the solvent-soluble layer by applying a solvent to the substrate.

[0012] US Patent Publication No. US6511701B1 describes a method for coating a polymer substrate with a dry composition containing particles. The polymer substrate to be coated can be any polymer material.

[0013] US Patent Publication No. US9172085B2 describes a current collector and method for electrodes useful in electrochemical cells. The current collector described includes a metal substrate, a substantially uniform nanoscale carbon coating, and an active electrode material.

[0014] International Patent Publication WO2018175022A1 describes a method for producing a buff-coated article. The method includes disposing a bonding layer on at least a portion of a major surface of a substrate and buff-coating at least a portion of the bonding layer with a powder. The method for producing a buff-coated article includes the following steps: (a) providing a substrate having a major surface; (b) disposing a bonding layer on at least a portion of the major surface; and (c) buff-coating at least a portion of the bonding layer with a powder.

[0015] Advanced ceramic and non-ceramic films and methods for producing such films with or without a substrate are provided. This method allows nanosheet-like crystalline ceramic or non-ceramic materials to be coated onto a polymer or metal substrate by applying shear force, and these ceramic or non-ceramic films can be produced without a substrate by burning out the substrate at high temperatures. This method also facilitates the coating process by chemically modifying the ceramic or non-ceramic materials before coating, allowing for the coating of nanosheet materials with a wider variety of compositions, thicknesses, and geometric anisotropies. Furthermore, this method results in a highly crystalline grain texture in the resulting film. This texture can promote high anisotropy in heat and / or charge carrier transport, which may be desirable in certain practical applications. Therefore, there is a need for the development of the aforementioned ceramic and non-ceramic films and methods for producing them. [Prior art documents] [Patent documents]

[0016] [Patent Document 1] Canadian Patent No. 2213209 [Patent Document 2] Japanese Patent No. 3554523 [Patent Document 3] European Publication No. 2975659 [Patent Document 4] Korean Publication No. 20100099380 [Patent Document 5] U.S. Publication No. 20070039641 [Patent Document 6] China Publication No. 104890325 [Patent Document 7] International Publication No. 2013191939 [Patent Document 8] U.S. Patent No. 6,511,701 [Patent Document 9] U.S. Patent No. 9,172,085 [Patent Document 10] International Publication No. 2018175022 [Non-patent literature]

[0017] [Non-Patent Document 1] "Electrochemical investigations of Na0.7CoO2 cathode with PEO-NaTFSI-BMIMTFSI electrolyte as a promising material for Na-rechargeable battery" Summary of the Invention [Problem to be solved by the invention]

[0018] Object of the invention The object of the present invention is to develop a textured film and a method for its manufacture that allows for the production of textured films with or without a substrate.

[0019] Another object of the present invention is to provide a textured film and method for its manufacture, wherein the resulting textured film can be used in electrical circuitry, heat shielding, and electrocatalytic applications.

[0020] Detailed Description of the Invention The textured film and method of manufacturing the same developed to achieve the objects of the present invention are shown in the accompanying drawings. [Brief explanation of the drawings]

[0021] [Figure 1] This is a schematic diagram showing (a) a nanosheet film on a substrate, (b) a nanosheet film shear-force coated onto a substrate surface, (c) a textured film on a substrate, and (d) a textured film without a substrate. [Figure 2]This is a schematic diagram of (a) a textured nanosheet film shear-force coated onto a substrate surface, (b) a textured nanosheet film in which a polymer binder has been mixed into the film and shear-force coated onto a substrate surface, (c) a textured nanosheet film that has been shear-force coated but has no substrate, and (d) a textured nanosheet film in which a polymer binder has been mixed into the film and has been shear-force coated but has no substrate. [Figure 3] This is a cross-sectional scanning electron microscope (SEM) image of the resulting substrate-free NaxCoO2 ceramic film. [Figure 4] These are scanning electron microscope (SEM) images of the top surface of the resulting substrate-free NaxCoO2 ceramic film taken at different magnifications: (a) 10,000x, (b) 5,000x, and (c) 1,000x. [Figure 5] These are scanning electron microscope (SEM) images of the top surface of a Bi2Te3 film obtained on a polyimide substrate taken at different magnifications: (a) 50,000x, (b) 5,000x, and (c) 10,000x. [Figure 6] These are scanning electron microscope (SEM) images of the top surface of a SnO film fabricated on a polyvinyl alcohol substrate, observed at different magnifications: (a) 50,000x, (b) 30,000x, and (c) 5,000x. [Figure 7] This is a schematic of an area detector X-ray diffraction study of the resulting textured film of NaxCoO2 single-crystalline nanosheets. The 2θ and χ axes are indicated. [Figure 8] This is shown in Figure 6, where (a) the intensity of the (00L) peak, (b) the integrated intensity within ±20 degrees of the peak, and (c) the integrated intensity within ±90 degrees of the peak are plotted against the chi-axis from a textured film of NaxCoO2 single-crystal nanosheets. As the single-crystal texture in the film increases, the width of the peak in the chi-axis narrows. Each part in the figure is individually numbered, and the correspondence between these numbers is shown below.

Description of Symbols

[0022] 1: Nanoscale sheet 2: Substrate 3: Second flat surface 4: Polymer binder 5: Foam pad

[0023] Means for Solving the Problem Metal oxide M1 x M2 y M3 z O or metal chalcogenide M4 w M5 p At least one of Ch or metal oxide M1 x M2 y M3 z O and metal chalcogenide M4 w M5 p A film comprising a plurality of single-crystal nanoscale sheets (1) composed of the nanoscale sheet (1) composition of both Ch, - M1 is an alkali metal or an alkaline earth metal, - M2 is a second alkali metal or an alkaline earth metal, - M3 is a transition metal or a post-transition metal with an atomic number of about 78 or less, - M4 is a transition metal or a post-transition metal with an atomic number of about 78 or less, - M5 is a second transition metal or a post-transition metal with an atomic number of about 78 or less, - Ch is a chalcogen, - x, y, z, w, and p independently vary within the ranges of 0.2 < x < 1.3, 0 < y < 0.5, 0.2 < z < 1, 0.3 < w < 1, and 0.2 < p < 1, The nanoscale sheet (1) is - The in-plane mutually perpendicular lateral sheet dimensions exceed about 10 nanometers × about 10 nanometers and are less than about 500 micrometers × 500 micrometers, and also - The thickness is from about 1 to about 500 nanometers, - a film in which the angle between the film normal and the c-axis of at least 70% of the nanosheets (1) is less than 30 degrees.

[0024] 1. A method for producing a textured film, comprising the steps of: - Metal oxide M1 x M2 y M3 z O or metal chalcogenide M4 w M5 p At least one of Ch or metal oxide M1 x M2 y M3 z O and metal chalcogenides M4 w M5 p a step of chemically reacting a plurality of single-crystalline nanosheets (1) consisting of both Ch and Ch in an acidic aqueous solution; - separating the chemically reacted single-crystalline nanosheets (1) from the acidic aqueous solution; - washing the separated single-crystalline nanosheets (1) with water; - dispersing the water-washed single-crystalline nanosheets (1) in a liquid having a vapor pressure of more than 0.012 atmospheres at room temperature; - adding an alkaline or alkaline earth basic aqueous solution to the dispersion of the nanosheets (1), thereby further chemically reacting the dispersion of the nanosheets (1); - separating a viscous, immiscible liquid phase containing visible chemically reacted nanosheets (1) from the nanosheet (1) dispersion; - placing a viscous liquid containing nanosheets (1) on a flat polymer or metal substrate (2); - pressing the viscous liquid containing the nanosheet (1) onto a flat polymer or metal substrate (2) using a second flat surface (3), while simultaneously using the same second flat surface (3) to move the second flat surface (3) in a direction parallel to the surface of the flat polymer or metal substrate (2), thereby applying a shear force perpendicular to the pressing axis, thereby coating the viscous liquid containing the nanosheet (1) onto the surface of the flat polymer or metal substrate (2); - removing the liquid portion of the viscous liquid containing the coated nanosheets (1) by drying the liquid; - heating the coated and dried film of nanosheets (1) to further chemically modify the nanosheets (1) and / or remove the polymer or metal substrate (2), finally forming a metal oxide M 1x M 2y M 3z O or metal chalcogenide M4 w M5 p At least one of Ch or metal oxide M 1x M 2y M 3z O and metal chalcogenides M4 w M5 p providing a film comprising a plurality of single-crystalline nanosheets (1) of both compositions of Ch, and free of a polymer or metal substrate (2); A method for producing a textured film, comprising: DETAILED DESCRIPTION OF THE INVENTION

[0025] We have developed a new nanomaterial processing technique for producing polycrystalline thermoelectric ceramic films using nanosheets (1) on polymer or metal substrates (2). The nanosheets (1) are modified depending on their chemical composition. The nanosheets (1) are then coated with a metal oxide M1 x M2 y M3 z O or metal chalcogenide M4 w M5 p At least one of Ch or metal oxide M1 x M2 y M3 z O and metal chalcogenides M4 w M5 p It is possible to obtain a single-crystalline nanosheet (1) consisting of both the Ch and Ni nanosheets.

[0026] The metal material of the metal substrate (2) in the coating is selected from the group consisting of metal substrates (2). The metal substrate (2) has one or more non-metallic support layers on one of its two surfaces, the surface opposite to the surface on which the film layer of the nanosheet (1) is attached. The non-metallic layer is selected from the group consisting of paper, plastic, or a combination of these two, and has a thickness of about 10 to 250 micrometers.

[0027] The polymer substrate (2) can be selected from polyvinyl alcohol, polyethylene, polyacrylic acid, polyimide, polyvinylidene fluoride, poly(methyl methacrylate), and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate. The thickness of the polymer substrate (2) is about 10 to 250 micrometers (μm).

[0028] A polymer binder (4), preferably at room temperature for 10 -9 A polymer binder (4) having an electronic conductivity of more than S / m is mixed with a metal oxide M1 x M2 y M3 z O or metal chalcogenide M4 w M5 p At least one of Ch or metal oxide M1 x M2 y M3 z O and metal chalcogenides M4 w M5 p Ch is mixed with multiple single-crystalline nanosheets (1) consisting of both compositions.

[0029] The nanosheet (1) materials coated on polymer or metal substrates (2) belong to the ceramic group and exhibit thermal and electrical conductivity, high temperature resistance, and high Seebeck values. These modified nanosheets (1) are coated onto polymer or metal substrates (2) using shear force.

[0030] At room temperature, the dispersion having a vapor pressure exceeding 0.012 atm is selected from the group including isopropyl alcohol, hexane, ethanol, methanol, and acetone. The liquid dispersion of the nanosheet (1) or the viscous liquid containing the nanosheet (1) is disposed on a flat polymer or metal substrate (2) by spraying the liquid dispersion of the nanosheet (1) onto the flat polymer or metal substrate (2) via ultrasonic waves or a pressure nozzle. The coating of the liquid dispersion of the nanosheet (1) or the viscous liquid containing the nanosheet (1) is performed under an inert gas selected from the group consisting of Ar, N2, and He, and a nanosheet (1) film composition with a reduced oxygen content is provided.

[0031] The film nanosheet (1) has in-plane mutually perpendicular lateral sheet dimensions exceeding about 20 nanometers × about 20 nanometers and smaller than about 500 micrometers × 500 micrometers. The thickness of the film nanosheet (1) is from about 1 to about 500 nanometers, and the angle between the film normal and at least 70% of the c-axis of the nanosheet (1) is less than 15 degrees. The nanosheet (1) has in-plane mutually perpendicular lateral sheet dimensions exceeding about 20 nanometers × about 20 nanometers and smaller than about 50 micrometers × 50 micrometers, and a thickness of from about 1 to about 400 nanometers. The plurality of single-crystal nanosheets (1) have in-plane mutually perpendicular lateral sheet dimensions exceeding about 20 nanometers × about 20 nanometers and smaller than about 10 micrometers × 10 micrometers, and also a thickness of from about 1 to about 50 nanometers. The plurality of single-crystal nanosheets (1) contain a single-crystal Na m CoO2 material composition, with in-plane mutually perpendicular lateral sheet dimensions exceeding about 10 microns × about 200 microns and a thickness of from about 5 to about 400 nanometers. The plurality of single-crystal nanosheets (1) contain a single-crystal Bi2 2-k Te3 or Sb2 2-k Te3 material composition, with in-plane mutually perpendicular lateral sheet dimensions less than about 2 microns × about 10 microns and a thickness of from about 1 to about 50 nanometers. The plurality of single-crystal nanosheets (1) contain a single-crystal Sn with -0.2 < r < 0.21-r It contains an O material composition, with in-plane mutually perpendicular lateral sheet dimensions of less than about 1 micron × about 50 microns and a thickness of about 5 to about 500 nanometers. The plurality of single-crystalline nanosheets (1) are single-crystalline Sn with -0.2 < n < 0.2 1- It contains a mixture of an nO material composition and a polymer binder (4), with in-plane mutually perpendicular lateral sheet dimensions of about 1 micron × less than about 50 microns and a thickness of about 5 to about 500 nanometers. The plurality of single-crystalline nanosheets (1) are single-crystalline Na with 0.2 < s < 0.9 s It contains a mixture of a CoO2 material composition and a polymer binder (4), with in-plane mutually perpendicular lateral sheet dimensions of about 10 microns × less than about 200 microns and a thickness of about 5 to about 400 nanometers. The second flat surface (3) during coating is selected from the group of polymer materials. The hydrophilicity of the second flat surface (3) made of polymer is changed so as to suppress the nanosheet (1) from being coated on the second flat surface (3) made of polymer rather than on the polymer substrate (2). The second flat surface (3) during coating is selected from the group consisting of a foam pad (5), a microfiber cloth, and a wool fabric. The second flat surface (3) made of polymer is supported by the foam pad (5) on a surface not in contact with the coating.

[0032] Metal oxide M1 x M2 y M3 z O or metal chalcogenide M4 w M5 p At least one type of Ch or metal oxide M1 x M2 y M3 z O and metal chalcogenide M4 w M5 p A ceramic film on a polymer or metal substrate (2) containing a plurality of single-crystalline nanosheets (1) composed of both compositions of Ch. M1 is an alkali metal or alkaline earth metal ( 3 Li, 11 Na, 19 K, 4 Be, 12 Mg, 20 Ca and38 is Sr). M2 is a second alkali metal or alkaline earth metal. M3 is a transition metal or post-transition metal having an atomic number of about 78 or less ( 22 Ti, 23 V, 24 Cr, 25 Mn, 26 Fe, 27 Co, 28 Ni and 30 Zn). M4 is a transition metal or post-transition metal having an atomic number of about 78 or less ( 42 Mo, 74 W, 83 Bi, 82 Pb, 51 Sb and 50 Sn). M5 is a second transition metal or post-transition metal having an atomic number of about 78 or less. Ch is a chalcogen ( 8 O, 16 S, 34 Se and 52 Te). x, y, z, w, and p are independently variable within the ranges of 0.2 < x < 1.3, 0 < y < 0.5, 0.2 < z < 1, 0.3 < w < 1, and 0.2 < p < 1.

[0033] The coated modified nanosheet (1) is recrystallized during the heating process. The heating is carried out under hydrogen gas, or under an inert gas selected from the group consisting of Ar, N2, and He, or under a mixture of hydrogen gas and an inert gas selected from the group consisting of Ar, N2, and He, and a nanosheet (1) film composition with a reduced oxygen content is provided. Metal oxide M1 x M2 y M3 z O or metal chalcogenide M4 w M5 p at least one of Ch or metal oxide M1 x M2 y M3 z O and metal chalcogenide M4 w M5 pA film comprising a plurality of single crystal nanosheets (1) composed of both Ch nanosheet (1) compositions. M1 is an alkali metal or an alkaline earth metal. M2 is a second alkali metal or an alkaline earth metal. M3 is a transition metal or a post-transition metal having an atomic number of about 78 or less. M4 is a transition metal or a post-transition metal having an atomic number of about 78 or less. M5 is a second transition metal or a post-transition metal having an atomic number of about 78 or less. Ch is a chalcogen. x, y, z, w, and p are independently variable within the ranges of 0.2 < x < 1.3, 0 < y < 0.5, 0.2 < z < 1, 0.3 < w < 1, and 0.2 < p < 1. These nanosheets (1) have in-plane lateral sheet dimensions that exceed about 10 nm × about 10 nm and are less than about 500 μm × 500 μm. The thickness of the film is from about 1 to about 500 nm. The angle between the film normal and at least 70% of the c-axes of the nanosheets (1) is less than 30 degrees. Recrystallization is applied to grow new particles without phase change. After heating, M1 x M2 y M3 z The O nanosheet (1) acquires thermoelectric properties and is produced as a thin film. XRD (X-ray powder diffraction) was used to confirm the crystal phase and texture of the obtained film. M1 x M2 y M3 z SEM was used to examine the orientation of the O nanosheet (1).

[0034] The polymer or metal substrate (2) is heated while coating with a liquid dispersion of nanosheets (1). The polymer or metal substrate (2) is heated while coating with a viscous liquid containing nanosheets (1). The nanosheets (1) in the film have in-plane, mutually perpendicular lateral sheet dimensions of greater than about 10 nanometers by about 10 nanometers and less than about 500 micrometers by 500 micrometers, a thickness of about 1 to about 500 nanometers, and an angle between the film normal and the c-axis of at least 70% of the nanosheets (1) is less than 30 degrees. The nanosheet (1) film coated and dried on the polymer substrate (2) is heated to a temperature of 250°C to 900°C to remove the polymer substrate (2), and finally, a metal oxide M1 is formed. x M2 y M3 z O or metal chalcogenide M4 w M5 p At least one of Ch or metal oxide M1 x M2 y M3 z O and metal chalcogenides M4 w M5 p A substrate-free film (2) is obtained, comprising a plurality of single-crystalline nanosheets (1) of both compositions of Ch. The film coated on the polymer or metal substrate (2) has in-plane, perpendicular lateral sheet dimensions of greater than about 20 millimeters by about 20 millimeters, and a thickness of about 20 nanometers to about 900 micrometers. The coated film without the polymer substrate (2) has in-plane, perpendicular lateral sheet dimensions of greater than about 20 millimeters by about 20 millimeters, and a thickness of about 20 nanometers to about 900 micrometers. The nanosheet (1) film coated and dried on the polymer or metal substrate (2) is heated to a temperature of 250°C to 550°C, ultimately forming a metal oxide M1. x M2 y M3 z O or metal chalcogenide M4 w M5 p At least one of Ch or metal oxide M1 x M2 y M3z O and metal chalcogenides M4 w M5 p Films containing multiple single-crystalline nanosheets (1) of both Ch and NiO are obtained on polymer or metal substrates (2). The resulting ceramic films contain nanosheets (1), and the thickness of these nanosheets (1) is 100-400 nm based on SEM images. The thickness of the resulting ceramic films was measured to be 9-70 μm based on SEM images. Finally, the thermoelectric properties of the resulting ceramic films were measured using a thermoelectric analyzer at temperatures from 160 K to 340 K. These measurements indicated that the ceramic films had electrical resistivities of 3.21 milliohms × cm (mΩ × cm) and Seebeck coefficients greater than 65 μV / K. The ceramic films on polymer substrates (2) have sheet dimensions greater than approximately 20 mm × approximately 20 mm in the mutually perpendicular lateral directions in the plane, and thicknesses of approximately 20 nanometers to approximately 50 micrometers. The ceramic film without the polymer substrate (2) has in-plane, mutually perpendicular lateral sheet dimensions of greater than about 40 millimeters by about 40 millimeters, and a thickness of from about 200 nanometers to about 950 micrometers.

[0035] The present invention provides several advantages, some of which are: - The resulting ceramic films exhibit electrical or thermal conductivity and are used in many fields, including electrical circuits, thermal insulation, thermoelectric applications, and lighting. - The resulting ceramic film has high resistance to high temperatures and oxidation. is. [Example]

[0036] Example 1: Step 1: Na x Synthesis of CoO2 nanosheets (1) Sodium nitrate (NaNO3, Merck, 99%), cobalt(II) nitrate hexahydrate (Co(NO3)2·6H2O, Alfa Aesar, 97.7%), and polyacrylic acid (PAA) [-CH2CH(CO2H)-] (Alfa Aesar, 25 wt% liquid) were used as received without further purification. The synthesis was carried out by preparing an aqueous solution of PAA, cobalt nitrate hexahydrate, and sodium nitrate in deionized water (DI water) at room temperature. The concentrations of sodium nitrate and cobalt nitrate hexahydrate in the solution were 0.165 M and 0.230 M, respectively. The ratio of PAA carboxylate groups to total metal ions in the solution was 2:1. The solution was heated to 150 °C on a hot plate. After 80% of the initial volume of the solution was evaporated, a highly viscous, dark red liquid was obtained. This viscous liquid was then spontaneously combusted on another hot plate at 500 °C. At the end of the spontaneous combustion process, the solution turns into a black powder, which is then calcined in a muffle furnace in air at 800°C for 6 hours.

[0037] Step 2: Na x Acid treatment of CoO2 nanosheets (1) Na x CoO2 nanosheets (1) were treated with 3 M hydrochloric acid (HCl) (37%, Merck EMURE) solution. x For CoO2 nanosheets (1), 1 ml of 3 M HCl solution is used. The reaction is carried out at room temperature for 24 hours with continuous stirring. The solution is filtered and the wet powder is washed with DI water to remove residual acid and salts. The powder is allowed to dry in air overnight.

[0038] the acidic aqueous solution is selected from the group consisting of aqueous HCl, HBr and HF solutions with a molar concentration of 0.5M to 5M; The basic aqueous solution of alkali or alkaline earth elements is selected from the group consisting of aqueous solutions of NaOH, KOH, Ca(OH)2 and Ba(OH)2 with a molar concentration of 0.5M to 5M.

[0039] Step 3: Na x Base treatment of CoO2 nanosheets (1) Acid-treated Nax To obtain CoO2 nanosheets (1), 5 ml of 3 M NaOH solution was added, followed by dispersion in isopropyl alcohol (IPA) - C3H8OH (Tekkim Kimya, 99.5%) with continuous stirring for 1 hour. Upon addition of the NaOH solution, the dispersion separates into two distinct liquid phases. One of these liquid phases is highly viscous and traps all of the nanosheets (1), while the other remains optically transparent. The viscous fraction is separated and used for coating.

[0040] Step 4: Na x Shear Force Coating of CoO2 Nanosheet (1) Dispersion Na x The CoO2 nanosheet (1) dispersion is coated onto a 70 μm thick polyvinyl alcohol (PVA) polymer film using shear force. x A viscous liquid containing CoO2 nanosheets (1) is lightly pressed onto the surface of a PVA substrate (2) using a foam pad (5), while simultaneously moving the foam pad (5) in a direction parallel to the surface of the PVA substrate (2), applying a shear force perpendicular to the pressing axis. This shear force-based coating can be easily achieved using an orbital sanding machine equipped with a foam pad (5) attachment. During the coating process, the substrate (2) is heated to <75°C by a custom-designed heating plate. This heating promotes rapid evaporation of IPA between coating cycles and may also soften the PVA substrate (2). The coating and evaporation cycle can be repeated to increase the thickness and quality of the coating. After coating, the polymer film underneath the textured film is removed by baking at 700°C for 3 hours. The final product is a free-standing NaO2 nanoparticle free of the substrate (2). x CoO2 nanosheet (1) film.

[0041] Example 2: Step 1: Synthesis of Bi2Te3 nanosheets (1) Dissolve 0.485 g of Bi(NO3)3·5H2O, 0.332 g of Na2TeO3, and 0.2 g of PVP in ethylene glycol and add 0.4 g of NaOH. Stir the solution until clear, then transfer it to a Teflon-lined stainless steel autoclave and heat it at 180 °C for 12 hours. After cooling to room temperature, the resulting silvery powder is collected by centrifugation, washed several times with ethanol and water, and finally dried in vacuum at 60 °C.

[0042] Step 2: Shear force coating of Bi2Te3 nanosheets (1) 1.6 g of in-house prepared Bi2Te3 nanosheets (1) were dispersed in 50 ml of isopropyl alcohol (IPA) with a vapor pressure above 0.012 atm for 12 h at room temperature using an ultrasonic bath to form a simple metastable suspension with a thickness of 50 μm and a volume of 20 × 25 cm. 2 A polyimide (Kepton) film (2) was used as the substrate (2) and placed on a custom-made hotplate set at 50 °C during the coating process. The Bi2Te3 nanosheet (1) dispersion was sprayed onto a polyimide film substrate (2) that had been pretreated with a plasma activation device to enhance the wetting of the polyimide substrate (2). As in Example 1, the Bi2Te3 nanosheet (1) dispersion was gently shear-coated onto the polyimide substrate (2). However, the foam pad (5) was covered with another polyimide film that had not been plasma-activated, making it more hydrophobic than the polyimide substrate (2) to be coated. This spray-coating-drying cycle was performed under a continuous N2 gas flow over the surface of the substrate (2) and repeated as necessary to increase the film thickness or improve film uniformity. Finally, the prepared film was sintered at 400 °C for 1 hour in a glove box.

[0043] Bi2 2-k Te3 or Sb2 2-kThe film on the polyimide substrate (2) containing the Te nanosheets (1) is heated to a temperature of 250 to 550°C under an inert gas selected from the group consisting of Ar, N2, and He, or a mixture of hydrogen gas and an inert gas selected from the group consisting of Ar, N2, and He, to form Bi2 on the polyimide substrate (2). 2-k Te3 or Sb2 2-k A Te3 nanosheet (1) film composition is obtained.

[0044] In one embodiment, Bi2 on the substrate (2) 2-k Te3 or Sb2 2-k The synthesis of Te3 nanosheet (1) film involves the following steps: - -0.2 <k<0.2であるBi2 2-k Te3 or Sb2 2-k Dispersing a plurality of single-crystalline nanosheets (1) of Te3 material composition in an alcohol solvent having a vapor pressure of more than 0.012 atmospheres at room temperature; - Bi2 2-k Te3 or Sb2 2-k A step of placing a dispersion of Te3 nanosheets (1) in an alcohol solvent on a flat polyimide substrate (2) that has been modified to reduce the hydrophobicity of the surface to be coated; - On a flat polyimide substrate (2), Bi2 2-k Te3 or Sb2 2-k A process of coating a dispersion of Te nanosheets (1) in an alcohol solvent with a second flat surface (3) made of another polyimide material having a more hydrophobic surface than the flat polyimide substrate (2) is used. 2-k Te3 or Sb2 2-k A step of pressing a dispersion of Te3 nanosheets (1) in an alcohol solvent onto a flat polyimide substrate (2) and simultaneously using a second flat surface made of the same polyimide to move the second flat surface made of polyimide in a direction parallel to the surface of the flat polyimide substrate (2), thereby applying a shear force perpendicular to the pressing axis; - Coated Bi2 2-k Te3 or Sb2 2-kThe liquid portion of the alcohol solvent dispersion of Te3 nanosheets (1) was removed by evaporation, and the nanosheets were deposited on a polyimide substrate (2) at a temperature of -0.2 <k<0.2のBi2 2-k Te3 or Sb2 2-k forming a film containing Te nanosheets (1); Includes:

[0045] Example 3: Step 1: Synthesis of SnO nanosheets (1) Tin(II) chloride dihydrate - SnCl2·2H2O (Merck, 98%), Cetyltrimethylammonium bromide (CTAB) - CH3(CH2) 15 N(CH3)3Br (Alfa Aesar, 98%), potassium hydroxide - KOH, deionized water (DI water), and ethanol were used without further purification. To prepare single nanosheets of SnO (1), SnCl2·2H2O (15 mmol) was added to Sn +2 SnO nanosheets (1) were used as precursors. CTAB was used as a structure-directing agent. SnCl2·2H2O and CTAB (0.75 mmol) were dissolved in 25 ml of deionized water with continuous stirring. After dissolving the chemicals, the solution was transferred to an ultrasonic cleaning bath (HydraUltrasonic, UltraClean). Under sonication, 10 ml of KOH solution (65 mmol) was added to the solution. All process steps were carried out at room temperature. After sonication, the SnO nanosheets (1) were washed several times with deionized water and ethanol, and the resulting precipitate was dried overnight at 65 °C in a drying oven.

[0046] Step 2: Shear force coating of SnO nanosheets (1) 12 mmol of SnO nanosheet (1) powder was dispersed in 50 ml of isopropyl alcohol (IPA) - C3H8OH (Tekkim Kimya, 99.5%) by stirring and ultrasonication. Polyvinylpyrrolidone (PVP) was also added to the dispersion at 1 wt% as a polymer binder. The resulting dispersion was sprayed and shear-coated onto a PVA substrate (2) as in Example 1. The thickness of the PVA substrate (2) was 70 μm. The IPA dispersion of SnO nanosheet (1) was placed on an area of ​​approximately 200 mm x 200 mm of the substrate (2). During the shear-coating process, the substrate (2) was heated to 60 °C on a heating plate to evaporate the IPA. Shear-coating was performed using a foam pad (5) as in Example 1. The coated film was sintered in air at 450 °C for 4 hours.

[0047] Sn 1-r The film on the PVA substrate (2) containing the O nanosheets (1) was heated to temperatures between 450 and 850 °C in air, and the PVA substrate (2) was removed to obtain a Sn nanosheet-free film. 1-r Obtain the O nanosheet (1) film composition.

[0048] Polyvinylpyrrolidone (PVP) 1-r The nanosheets (1) were added to an alcohol solvent dispersion, and finally, Sn 1-r A film containing O nanosheets (1) and PVP is obtained.

[0049] In one embodiment, Sn on the substrate (2) 1-r The synthesis of nanosheet (1) films involves the following steps: - In alcoholic solvents with a vapor pressure of more than 0.012 at room temperature, -0.2 <r<0.2であるSn 1-r Dispersing a plurality of single-crystalline nanosheets (1) of the O material composition; - Sn 1-r A step of disposing an alcohol solvent dispersion of O nanosheets (1) on a flat PVA substrate (2); - Using the second flat surface (3) of the foam pad (5), Sn 1-rThe alcohol solvent dispersion of the O nanosheets (1) was pressed onto a flat PVA substrate (2), and at the same time, the flat surface of the second foam pad (5) was moved in a direction parallel to the surface of the flat PVA substrate (2) using the same surface of the second foam pad (5), thereby applying a shear force perpendicular to the pressing axis, and the Sn nanosheets were formed. 1-r A step of coating an alcohol solvent dispersion of O nanosheets (1) onto a flat PVA substrate (2); - Coated Sn 1-r The liquid portion of the alcohol solvent dispersion of O nanosheets (1) was removed by evaporation, and the resulting dispersion was cooled to -0.2 <r<0.2であるSn 1-r forming a film containing O nanosheets (1) on a PVA substrate (2); Includes:

[0050] Area detector XRD characterization to quantify the orientation of nanosheets (1) in shear-stress coated films: X-ray diffraction studies were carried out using an area detector and single crystal Na x Within the film of CoO nanosheets (1), it was quantitatively verified that the single-crystalline nanosheets (1) were well oriented along the c-axis (Figure 7). The angle between the sample stage and the incident linear X-ray beam was adjusted so that the X-rays were inclined to the sample surface at an angle half the 00L diffraction 2θ peak angle (for example, the Na in Example 1, where the X-ray wavelength is 0.709). x In the case of CoO2 single crystal nanosheet (1), 2θ = 7.42 and θ = 3.71 (see Figure 7). x The film of the CoO nanosheet (1) sample is oriented on the sample stage so that the top surface of the film is parallel to the sample stage (i.e., the film normal is perpendicular to the sample stage). x The area detector X-ray diffraction plot of the CoO2 nanosheet (1) sample is shown along the 2θ and χ axes. The distinct peaks along 2θ indicate diffraction from different lattice spacings, and the different peaks along χ indicate different crystal orientations. The broadening of the (00L) peak along the χ axis indicates different crystal orientations within the sample. Single-crystal Na xThe (00L) peak of the CoO2 nanosheet (1) film shows a narrow broadening along the χ axis, which indicates that the nanosheet (1) crystal is a single-crystalline Na x The ratio of the X-ray diffraction signal intensity within ±20° of the Gaussian XRD peak to the signal intensity over the entire orientation range (±90°) was 0.804, indicating that all single-crystalline NaO nanosheets in the shear-coated film were well aligned (Fig. 8a). x This shows that 80.4% of the CoO2 nanosheets (1) are oriented within ±20° of the film plane.

[0051] According to an exemplary embodiment of the present invention, the resulting ceramic film (e.g., Na x CoO2 nanosheet (1) film) is used in battery electrodes. Battery electrodes containing this film are M1 x M2 y M3 z The nanosheets (1) comprise a plurality of single-crystalline nanosheets of O composition having in-plane mutually perpendicular lateral sheet dimensions of greater than about 1 millimeter by about 1 millimeter and a thickness of about 20 nanometers to about 1500 micrometers.

[0052] According to an exemplary embodiment of the present invention, the resulting textured film (e.g., Na x CoO2 and Bi2Te3 nanosheets (1) films) are used in thermoelectric devices, including films with in-plane mutually perpendicular lateral sheet dimensions greater than about 1 millimeter by about 1 millimeter, and thicknesses from about 20 nanometers to about 1500 micrometers.

Claims

1. Metal oxide M1 ｘ M2 ｙ M3 ｚ O or metal chalcogenide M4 ｗ M5 ｐ At least one of Ch or metal oxide M1 ｘ M2 ｙ M3 ｚ O and metal chalcogenide M4 ｗ M5 ｐ A film comprising a plurality of single-crystal nanosheets (1) consisting of both nanosheet (1) compositions of Ch, M1 is an alkali metal or alkaline earth metal; M2 is a second alkali metal or alkaline earth metal; M3 is a transition metal or post-transition metal having an atomic number of about 78 or less; M4 is a transition metal or post-transition metal having an atomic number of about 78 or less; M5 is a second transition metal or post-transition metal having an atomic number of about 78 or less; Ch is a chalcogen; x, y, z, w, and p are independently variable within the ranges 0.2<x<1.3, 0<y<0.5, 0.2<z<1, 0.3<w<1, and 0.2<p<1; The nanosheet (1) is the in-plane mutually perpendicular lateral sheet dimensions are greater than about 10 nanometers by about 10 nanometers and less than about 500 micrometers by 500 micrometers; and a thickness of about 1 to about 500 nanometers; A film, wherein the angle between the film normal and the c-axis of at least 70% of the nanosheets (1) is less than 30 degrees.

2. 10. The film of claim 1, M1 is at least one alkali metal or alkaline earth metal selected from the group consisting of Li, Na, K, Be, Mg, Ca, and Sr; M2 is omitted, M3 is at least one transition metal selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Zn, and Ni.

3. 10. The film of claim 1, M4 is at least one transition metal or post-transition metal selected from the group consisting of Mo, W, Bi, Pb, Sb, and Sn; M5 is omitted, Ch is at least one chalcogen selected from the group consisting of O, S, Se, and Te.

4. 10. The film of claim 1, The nanosheets (1) have in-plane, mutually perpendicular lateral sheet dimensions of greater than about 20 nanometers by about 20 nanometers and less than about 50 micrometers by 50 micrometers, and a thickness of about 1 to about 400 nanometers.

5. 10. The film of claim 1, Single crystal Na with m being 0.2<m<0.9 ｍ CoO ２ A film comprising only the material composition, having in-plane mutually perpendicular lateral sheet dimensions greater than about 10 microns by about 200 microns, and a thickness of from about 5 to about 400 nanometers.

6. 10. The film of claim 1, Single crystal Bi2 with -0.2<k<0.2 ２－ｋ Te ３ or Sb2 ２－ｋ Te ３ A film comprising only the material composition, having in-plane mutually perpendicular lateral sheet dimensions of less than about 2 microns by about 10 microns, and a thickness of from about 1 to about 50 nanometers.

7. 10. The film of claim 1, Single crystal Sn where -0.2<r<0.2 １－ｒ 1. A film comprising only the O material composition, having in-plane mutually perpendicular lateral sheet dimensions of less than about 1 micron by about 50 microns, and a thickness of from about 5 to about 500 nanometers.

8. 10. The film of claim 1, Single crystal Sn １－ｎ 1. A film comprising a mixture of an O material composition and a polymeric binder (4), wherein -0.2<n<0.2, having in-plane mutually perpendicular transverse sheet dimensions of less than about 1 micron by about 50 microns, and a thickness of about 5 to about 500 nanometers.

9. 10. The film of claim 1, Single crystal sodium ｓ CoO ２ A film comprising a mixture of a material composition and a polymeric binder (4), wherein 0.2<s<0.9, having in-plane mutually perpendicular transverse sheet dimensions of less than about 10 microns by about 200 microns, and a thickness of about 5 to about 400 nanometers.

10. 10. The film of claim 1, A film having in-plane mutually perpendicular lateral sheet dimensions of greater than about 40 millimeters by about 40 millimeters and a thickness of from about 200 nanometers to about 950 micrometers.

11. The film according to claim 1, comprising a plurality of single-crystalline nanosheets (1) of M1xM2yM3zO composition, the in-plane mutually perpendicular lateral sheet dimensions exceed about 1 millimeter by about 1 millimeter; A battery electrode having a thickness of about 20 nanometers to about 1500 micrometers.

12. The film of claim 1, the in-plane mutually perpendicular lateral sheet dimensions exceed about 1 millimeter by about 1 millimeter; A thermoelectric device having a thickness of about 20 nanometers to about 1500 micrometers.

13. A method for producing a film, comprising the steps of: Metal oxide M １ｘ M ２ｙ M ３ｚ O or metal chalcogenide M4 ｗ M5 ｐ At least one of Ch or metal oxide M １ｘ M ２ｙ M ３ｚ O and metal chalcogenide M4 ｗ M5 ｐ A step of chemically reacting a plurality of single-crystal nanosheets (1) consisting of both compositions of Ch in an acidic aqueous solution; A step of separating the chemically reacted single-crystal nanosheet (1) from the acidic aqueous solution; Washing the separated single-crystal nanosheet (1) with water; Dispersing the water-washed single-crystal nanosheet (1) in a liquid having a vapor pressure of more than 0.012 atmospheres at room temperature; A step of adding an alkaline or alkaline earth basic aqueous solution to the dispersion of the nanosheet (1) to further chemically react the dispersion of the nanosheet (1); Separating a viscous immiscible liquid phase visibly containing the chemically reacted nanosheets (1) from the nanosheet (1) dispersion; A step of disposing a viscous liquid containing the nanosheet (1) on a flat polymer substrate (2); a step of applying a shear force perpendicular to the pressing axis by using a second flat surface (3) to press the viscous liquid containing the nanosheet (1) onto the flat polymer substrate (2) while simultaneously using the same second flat surface (3) to move the second flat surface (3) in a direction parallel to the surface of the flat polymer substrate (2), thereby coating the viscous liquid containing the nanosheet (1) onto the surface of the flat polymer substrate (2); A step of removing the liquid portion of the viscous liquid containing the coated nanosheet (1) by drying the liquid; The coated and dried film of nanosheets (1) is heated to further chemically modify the nanosheets (1), or the polymer substrate (2) is removed, or both to further chemically modify the nanosheets (1) and remove the polymer substrate (2), finally producing a metal oxide M １ｘ M ２ｙ M ３ｚ O or metal chalcogenide M4 ｗ M5 ｐ At least one of Ch or metal oxide M １ｘ M ２ｙ M ３ｚ O and metal chalcogenide M4 ｗ M5 ｐ Providing a film comprising a plurality of the single-crystalline nanosheets (1) of both compositions of Ch and free of the polymer substrate (2); A method for producing a film, comprising:

14. 14. The method for producing a film according to claim 13, wherein the polymer substrate (2) can be replaced by a metal substrate (2).

15. A method for producing the film according to claim 13, comprising: disposing the liquid dispersion of the nanosheet (1) or a viscous liquid containing the nanosheet (1) on the flat polymer or metal substrate (2) by spraying the liquid dispersion of the nanosheet (1) onto the flat polymer or metal substrate (2) via an ultrasonic or pressure nozzle; A method for producing a film, comprising:

16. A method for producing the film according to claim 13, comprising: The method for producing a film, wherein the polymer material of the polymer substrate (2) during coating is selected from the group consisting of polyvinyl alcohol, polyethylene, polyacrylic acid, polyimide, polyvinylidene fluoride, poly(methyl methacrylate), and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate, and has a thickness of about 10 to 250 micrometers.

17. A method for producing the film according to claim 13, comprising: The metal material of the metal substrate (2) in the coating is selected from the group consisting of the metal substrates (2) described above, The metal substrate (2) has one or more non-metallic support layers on one of its two surfaces, the surface opposite to the surface on which the film layer of the nanosheet (1) is attached; The method of making a film, wherein the non-metallic layer is selected from the group consisting of paper, plastic, or a combination of the two, and has a thickness of about 10 to 250 micrometers.

18. 15. The method for producing a film according to claim 14, wherein the polymer or metal substrate (2) is heated during coating with the liquid dispersion of nanosheets (1).

19. The method for producing a film according to claim 14, wherein the polymer substrate (2) is heated during coating with a viscous liquid containing the nanosheets (1).

20. 14. The method for producing a film according to claim 13, wherein the second flat surface (3) during coating is selected from the group consisting of a foam pad (5), a microfiber cloth, and a wool fabric.

21. 14. A method for producing a film according to claim 13, wherein the second flat surface (3) of the polymer is supported by a foam pad (5) on the surface not in contact with the coating.

22. A method for producing the film according to claim 13, comprising: The acidic aqueous solution is selected from the group consisting of aqueous solutions of HCl, HBr, and HF with a molar concentration ranging from 0.5M to 5M, and the alkaline or alkaline earth basic aqueous solution is selected from the group consisting of aqueous solutions of NaOH, KOH, Ca(OH) with a molar concentration ranging from 0.5M to 5M. ２ and Ba(OH) ２ A method for producing a film selected from the group consisting of aqueous solutions.

23. A method for producing the film according to claim 13, comprising: The liquid dispersion of the nanosheet (1) or the coating of a viscous liquid containing the nanosheet (1) is applied to the nanosheet (1) by a method using Ar, N ２ and He, thereby providing the nanosheet (1) film composition having a reduced oxygen content.

24. A method for producing the film according to claim 13, comprising: The nanosheets (1) in the film have in-plane, mutually perpendicular lateral sheet dimensions of greater than about 10 nanometers by about 10 nanometers and less than about 500 micrometers by 500 micrometers, a thickness of about 1 to about 500 nanometers, and an angle between the film normal and the c-axis of at least 70% of the nanosheets (1) of less than 30 degrees.

25. A method for producing the film according to claim 13, comprising: Polymer binder (4), preferably at room temperature for 10 －９ A method for producing a film comprising a polymer binder (4) having an electronic conductivity greater than S / m.

26. A method for producing the film according to claim 13, comprising: A method for producing a film, comprising heating the nanosheet (1) film coated and dried on the polymer or metal substrate (2) to a temperature of 250°C to 900°C to remove the polymer or metal substrate (2).

27. A method for producing the film according to claim 13, comprising: The heating is carried out in a gas atmosphere of hydrogen, Ar, or N ２ an inert gas selected from the group consisting of hydrogen gas and Ar, N ２ and a mixture of an inert gas selected from the group consisting of He, to provide the nanosheet (1) film composition having a reduced oxygen content.

28. A method for producing the film according to claim 13, comprising: The coated film without the polymer substrate (2) has in-plane mutually perpendicular transverse sheet dimensions of greater than about 20 millimeters by about 20 millimeters and a thickness of about 20 nanometers to about 900 micrometers.

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