KR101264256B1 - Method for preparing nano ring array and metal nanoparticle array - Google Patents

Abstract

The present invention relates to a method for producing a string array of nano-ring and metal nanoparticle structure array by rearrangement of the self-assembled block copolymer reverse micelle arrangement, and to a nano-ring array and a metal nanoparticle structure array manufactured by the method. The nanoring arrays prepared by the method according to the invention can be used as templates to produce nanoparticle arrays of single metals as well as double particle nanoparticle arrays, and the unusual nanoparticle structures of such metals can be used for chemicals, biomaterials and diseases. It can be usefully used for diagnostic sensors.

Description

Method for preparing nano ring array and metal nanoparticle array {Method for preparing nano ring array and metal nanoparticle array}

The present invention provides a method for producing a string array nano ring array by rearranging the self-assembled block copolymer reverse micelle array, a method for producing a metal nanoparticle structure array using the nano ring array and a nano ring manufactured by the method An array and an array of metal nanoparticle structures.

Self-assembly technology has recently been in the spotlight as a tool for manufacturing nanoscale devices such as medical, electronic / information, optical, or sensors. For example, two-dimensional or three-dimensional assemblies of monodisperse nanoparticles are used in functional coatings, dye-free paints, and the like, and for templates, light splitting, optical filters, and photonic crystals for the growth of arrayed micro or nanoporous materials. It has been utilized in optical material and device applications.

Block copolymers are polymers in which two or more polymer chains are covalently linked through one end, and tend to phase separate each block into their respective domains due to the limitation of the covalent bond point between the two blocks. Such block copolymers may form periodic nanostructures having a size of about 10 nm to about 100 nm by spontaneous phase separation. The shape and size of these nanostructures are determined by the molecular weight of the block copolymers, the volume ratio of each block, and the Flory-Huggins interaction coefficient between each block. As such, it is possible to form micelles such as spheres and cylinders having a size of nanometers.

In addition, by using the self-assembly properties of the block copolymer, the size of the particles within the nanostructure of the block copolymer can be limited to nanometer size without any treatment, the arrangement of the particles in the size and spacing of the nanostructure Limited by the particle size and arrangement.

Dissolving the block copolymer in a solvent selective to only one block polymer can form micelles in which the solophilic block is spontaneously located in the corona and the nonsolvent block in the core spontaneously. In this case, micelles are classified into reverse micelles in which the hydrophilic block is located in an aqueous solution, and a solvent is an organic solvent.

There is a need for a new approach to fabricating nanostructures using the reverse micelles.

Accordingly, the present inventors prepared a block copolymer solution using a self-assembly technique of the block copolymer, and contacting it with the solvent vapor to obtain a string-shaped nanowire structure in which the block copolymer is rearranged, and then selectively The present invention has been developed a method for producing a nano-ring array of a string array in which pores are formed in the center by treating with a solvent, thereby completing the present invention.

Accordingly, it is an object of the present invention to provide a method for producing a string array of nano ring arrays that can be used for the production of various nanostructures.

Another object of the present invention to provide a method for producing a metal nanoparticle structure array using the nano ring array.

Another object of the present invention is to provide a nano ring array and a metal nanoparticle structure array produced by the above method.

In order to achieve the above object, the present invention comprises the steps of (a) applying a block copolymer solution containing a hydrophilic block and a hydrophobic block to the substrate; (b) contacting the substrate with solvent vapor; And (c) contacting the substrate with a solvent for selectively dissolving a hydrophilic block, and then, after the step (c), and (d) the nanoring array and the metal precursor solution. Contacting; And (e) provides a method for producing a metal nanoparticle structure array comprising the step of performing at least one selected from ultraviolet irradiation, oxygen plasma treatment and reducing agent treatment.

The present invention also provides a nano ring array and a metal nanoparticle structure array produced by the above method.

The nanoring array prepared by the method according to the present invention can be used as a template to prepare a nanoparticle array of various metals such as silver, gold, platinum, zinc oxide, as well as a double metal nanoparticle array in which silver and gold are present. The specific nanoparticle structure of such metals may be usefully used for chemicals, biomaterials, and sensors for diagnosing diseases.

1 is a process flow diagram illustrating a method of manufacturing a single metal nanoparticle structure of silver or gold and a method of manufacturing a double metal nanoparticle structure of silver and gold according to an embodiment of the present invention.
FIG. 2 is an atomic force micrograph of the block copolymer PS-b-P2VP reverse micelle template prepared in Example 1. FIG.
3 is an atomic force micrograph of a reverse micelle nanowire thin film rearranged through contact with a solvent vapor prepared in Example 1. FIG.
FIG. 4 is an atomic force micrograph of a string array of ring arrays in which the rearranged reverse micelle nanowire thin film structure of FIG. 3 is immersed in ethanol to form pores by swelling P2VP polymer chains onto the surface.
FIG. 5 is an atomic force micrograph of a string array of nanorings into which a silver metal precursor solution prepared in Example 1 is introduced.
FIG. 6 is a high magnification atomic force micrograph of FIG. 5.
FIG. 7 is an atomic force micrograph of an array of silver nanoparticle structures in a string array in which polymers are removed and silver ions are reduced by ultraviolet irradiation prepared in Example 1. FIG.
FIG. 8 is an X-ray photoelectron spectral broadband spectrum of a string array of silver nanoparticle structure arrays before and after reduction of the metal precursor prepared in Example 1. FIG.
9 is an X-ray photoelectron spectroscopy high resolution spectrum of a string array of silver nanoparticle structure arrays before and after metal precursor reduction prepared in Example 1. FIG.
10 is an atomic force micrograph of a string array nano ring array into which the gold metal precursor solution prepared in Example 2 is introduced.
FIG. 11 is an atomic force micrograph of an array of gold nanoparticle structures in a string array in which polymers are removed and gold ions are reduced by oxygen plasma treatment prepared in Example 2. FIG.
FIG. 12 is a high magnification atomic force micrograph of the gold nanoparticle structure array of FIG. 11.
FIG. 13 is an atomic force micrograph of the block copolymer PS-b-P2VP template prepared in Example 3. FIG.
14 is an atomic force micrograph of a reverse micelle nanowire thin film rearranged through a solvent annealing process prepared in Example 3. FIG.
FIG. 15 is an atomic force micrograph of a string array of nanoring arrays in which the thin film structure prepared in Example 3 was immersed in ethanol to swell P2VP polymer chains onto the surface.
16 is an atomic force micrograph of a string array of nano ring arrays introduced by immersion in a silver metal precursor and a gold metal precursor solution prepared in Example 3 in turn.
FIG. 17 is an atomic force micrograph of a double metal nanoparticle structure array of silver and gold in a string array in which silver and gold ions are reduced to form a polymer with sodium borohydride reducing agent prepared in Example 3. FIG.
FIG. 18 is an ultraviolet-visible spectrophotometer graph of local surface plasmon resonance (LSPR) properties of a double metal nanoparticle structure of silver and gold in a string arrangement in which a polymer prepared in Example 3 is present.
19 is an atomic force micrograph of a string array of nano ring arrays introduced by immersion in a gold metal precursor and a silver metal precursor solution prepared in Example 4 in sequence.
FIG. 20 is an atomic force micrograph of a double metal nanoparticle structure of gold and silver in a string arrangement in which gold and silver ions are reduced to form a polymer with sodium borohydride reducing agent prepared in Example 4. FIG.
FIG. 21 is an ultraviolet-visible spectrophotometer graph of local surface plasmon resonance (LSPR) properties of a double metal nanoparticle structure of gold and silver in a string arrangement in which a polymer prepared in Example 4 is present.

Definitions of terms used in the present invention are as follows.

As used herein, the term "reverse micelle" refers to a micelle, in which a hydrophobic block is spontaneously located on the outside of a block copolymer, and a hydrophilic block is located on the inside of a block copolymer.

As used herein, the term "nanowire thin film" means that the block copolymer is in contact with solvent vapor (solvent annealing process) so that reverse micelles of the respective block copolymers form a string arrangement adjacent to each other on the substrate. do. The term "nanowire thin film" is used herein in the same sense as "nano stream array."

As used herein, the term "nano ring" means that the hydrophilic block swells to the surface by contacting the nanowire thin film with a solvent that selectively dissolves the hydrophilic block to have a ring shape.

The term "nano ring array" used in the present invention means that each of the nano rings are arranged in a string arrangement adjacent to each other on a substrate.

As used herein, the term "metal nano particle structure (metal nano particle structure) means that the metal nanoparticles or metal nanoparticles are combined with the nano ring.

As used herein, the term "metal nano particle structure array (metal nano particle structure array) means that each of the metal nanoparticle structure on the substrate adjacent to each other in a string arrangement.

The present invention comprises the steps of (a) applying a block copolymer solution comprising a hydrophilic block and a hydrophobic block to the substrate; (b) contacting the substrate with solvent vapor; And (c) contacting the substrate with a solvent for selectively dissolving the hydrophilic block.

Step (a) of the present invention is a step of applying a block copolymer solution containing a hydrophilic block and a hydrophobic block on a substrate to form a monomolecular film.

The hydrophilic block may be one or more polymers selected from the group consisting of polyvinylpyridine, polyethylene oxide, polyacrylic acid, polymethacrylic acid, polyvinyl alcohol, polyacrylamide and polystyrenesulfonic acid, but is not limited thereto. no.

The hydrophobic block may be one or more polymers selected from the group consisting of polystyrene, polyolefin, polyalkylacrylate, polyisoprene, polybutadiene, polysiloxane, polyimidazole and polylactone (or polylactide), but is not limited thereto. It doesn't happen.

The substrate may be any one used in the art, but preferably, an inorganic substrate such as silicon wafer, glass, quartz or indium tin oxide (ITO), a polymer substrate such as PMMA, and the like may be used. Accordingly suitable materials may be used.

In the present invention, the solution of step (a) may be selected according to the type of block copolymer to be used and the kind of metal precursor, and the like, but the type is not particularly limited. Solutions comprising at least one selected from the group consisting of solvents that selectively dissolve the medium and hydrophobic blocks can be used.

For example, the solvent for selectively dissolving the hydrophobic block may use one or more solvents selected from the group consisting of toluene, chloroform, dimethylformamide, benzene, heptane and xylene. In addition, tetrahydrofuran (THF), dimethylformamide (DMF), and the like may be used as the cosolvent, but is not limited thereto as long as it is a cosolvent for hydrophilic and hydrophobic blocks.

In particular, a mixed solvent of the cosolvent and the hydrophobic block may be used, and more specifically, 0.2 to 0.7 parts by weight of the cosolvent having affinity with the hydrophilic block and the hydrophobic block with respect to 1 part by weight of the solvent for selectively dissolving the hydrophobic block. Mixed solvents can be used.

As such, when the cosolvent is mixed with the hydrophobic solvent, the mobility of the block copolymer may be increased in the solvent annealing process in the next step (b). If the weight part of the cosolvent is less than 0.2, the mobility of the block copolymer is reduced to lengthen the annealing time. If the annealing time is lengthened as such, the shape of the monomolecular film may be distorted. In addition, when the weight of the cosolvent is 0.7 or more, the weight of the cosolvent increases the mobility of the block copolymer, so that the annealing time may be shortened, but the thin film may swell and peel off from the surface.

In the present invention, the block copolymer may be prepared by adding 0.1 to 1% by weight in the solution of step (a). If the content is less than 0.1% by weight, the block copolymer monomolecular film of uniform density may not be produced, and when the content is more than 1% by weight, the block copolymer multilayer film may be produced.

In addition, in the present invention, the monomolecular film is prepared by a coating method used in the art, and preferably is prepared by a spin coating method. The spin coating conditions can be changed depending on the type of polymer used, the molecular weight, the solvent, and the thickness of the monomolecular film. For example, in the case of using polystyrene-block-poly (2-vinylpyridine) as the block copolymer, block air Coated reverse micelles may be spin coated at 1000 to 2500 rpm to prepare a coating layer. The rpm condition can be appropriately adjusted according to the type of block copolymer. If the rpm condition is less than 1000 rpm during spin coating, a reverse micelle multi-layer film may be generated. When the rpm condition exceeds 2500 rpm, a reverse micelle monolayer having a uniform density and thickness may not be induced.

In the present invention, the monomolecular film may include a block copolymer of reverse micelle form and / or non-micel form (chain form) according to the kind of solvent used.

In the step (b) according to the present invention, the monomolecular film prepared in the step (a) is contacted with solvent vapor using a saturated solvent gas so that the block copolymer is rearranged into a stream in a disordered phase. The step of preparing a thin film for the route.

The process of imparting flexibility and mobility to the polymer chain by using a saturated solvent gas is called a solvent annealing process. The solvent used in the solvent annealing process may use a cosolvent having a high affinity for two blocks of the block copolymer, and the annealing process may be performed at room temperature. In an environment in which an appropriate volume inside a closed vessel is saturated with solvent vapor, the block copolymer thin film swells and the polymer chains are rearranged to change into a disordered phase.

Cosolvents include, for example, tetrahydrofuran, dimethylformaldehyde, and the like, but are not limited thereto, and any solvent may be used as long as it has a high affinity for hydrophilic and hydrophobic blocks.

In the present invention, the time for applying the solvent annealing may vary depending on the type of solvent used, but may be performed for 10 minutes to 8 hours. If the solvent annealing time is shorter than 10 minutes, the block copolymer is not sufficiently shifted to be rearranged. If the solvent annealing time is longer than 8 hours, the monomolecular film may be distorted.

For example, when the weight ratio of the solvent for selectively dissolving the cosolvent and the hydrophobic block is about 1: 3, and the content of the cosolvent is low, it takes about 6 to 8 hours to apply the solvent annealing. On the other hand, when using only a co-solvent with a weight ratio of 1: 0, the time required for applying the solvent annealing is only about 10 to 30 minutes.

In step (c) according to the present invention, the nanowire thin film prepared in step (b) is contacted with a solvent selective to the hydrophilic block, so that the hydrophilic block is swollen onto the surface and at the same time a pore is formed in the center. Step of preparing a nano ring array.

Specifically, when the nanowire thin film is immersed in a solvent selective for the hydrophilic block, a string array of nano-rings in the form of a pore formed at the same time as the hydrophilic block is swollen over the surface may be manufactured. More specifically, when the thin film is immersed in ethanol, which is a solvent selective to the hydrophilic block, the hydrophilic block located inside is swollen and exposed on the outer surface to form a ring in which pores are formed in the center.

The solvent selective for the hydrophilic block may be one or more solvents selected from the group consisting of an alcohol solvent such as ethanol or methanol, an acidic solvent such as hydrochloric acid, or acetic acid, or a mixed solvent thereof.

In the present invention, the method of contacting the prepared nanowire thin film with the solvent is not particularly limited, but a method of dipping the nanowire thin film in a solvent may be used. The contact time can be immersed for 30 seconds to 2 hours, more specifically 5 minutes to 1 hour, even more specifically 10 minutes to 30 minutes. If soaked for too short, the hydrophilic block may not swell sufficiently, and if soaked for too long, the monomolecular film may be weakened.

The present invention also relates to a nano ring array produced by the above production method.

The nano-ring array has a nano-sized block copolymer is arranged adjacent to each other in the form of a string, the block copolymer has a hydrophobic block in the inner ring, a hydrophilic block in the outer ring, the pores in the middle The branch is characterized by a ring shape.

The nano ring has an average diameter of about 40 to 80 nm, and the average diameter of the mesopores is about 10 to 30 nm. The spacing between nanostreams is also about 10 to 30 nm.

Such a nano ring structure can be used as a template of various nanostructures such as metal nanoparticles.

The invention also comprises the steps of (a ') preparing a nano ring array by the method according to the invention;

(d) contacting the nano ring array with a metal precursor solution; And

(e) a method of manufacturing a metal nanoparticle structure array comprising performing at least one selected from ultraviolet irradiation, oxygen plasma treatment, and reducing agent treatment.

Step (d) according to the present invention is a step of introducing a metal precursor to the region of the hydrophilic block by immersing the array of nano-rings of the string array prepared according to the present invention in a metal precursor solution.

In the present invention, at least one selected from the group consisting of nitrates, sulfates, carbonates, acetates, bromide, chlorides, fluorides, hydroxides and hydrates of metals may be used as the metal precursor.

In the present invention, the metal may be a transition metal, an alkali metal, an alkaline earth metal, and the like, and more specifically, lithium (Li), beryllium (Be), sodium (Na), magnesium (Mg), aluminum (Al), potassium ( K), calcium (Ca), scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mg), iron (Fe), cobalt (Co), nickel (Ni), copper ( Cu, Zinc (Zn), Gallium (Ga), Germanium (Ge), Selenium (Se), Rubidium (Rb), Strontium (Sr), Zirconium (Zr), Niobium (Nb), Molybdenum (Mo), Technetium ( Tc), ruthenium (Ru), rhodium (Rh), palladium (Pd), silver (Ag), cadmium (Cd), indium (In), tin (Sn), antimony (Sb), tellurium (Te), cesium (Cs), Barium (Ba), Lanthanum (La), Cerium (Ce), Praseodymium (Pr), Neodymium (Nd), Promethium (Pm), Samarium (Sm), Europium (Eu), Gadolinium (Gd), Holmium (Ho), thulium (Tm), ytterbium (Yb), lutetium (Lu), hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt), gold (Au), mercury (Hg), thallium (Tl), lead (Pb), bismuth (Bi), It may be a metal selected from the group consisting of polonium (Po), francium (Fr), radium (Ra), actinium (Ac), uranium (U), neptunium (Np), plutonium (Pu) and mitenium (Mt). .

In the present invention, more specifically, a metal selected from the group consisting of gold, silver, platinum, palladium and zinc may be used, and the metal precursor may be nitrate, sulfate, carbonate, acetate, bromide, chloride, fluoride or hydroxide of the metal. And one or more selected from the group consisting of hydrates. In particular, as an example of the present invention, silver precursors include silver peroxide (Ag ₂ O), silver sulfide (Ag ₂ S), silver nitrate (AgNO ₃ ), silver sulfate (Ag ₂ SO ₄ ) and silver acetate (Ag (CH ₃ COO) ), And the like.

In addition, the metal precursor is mixed at 0.1 to 10% by weight with respect to the solvent. In this case, when the amount of the metal precursor is less than 0.1 wt%, a sufficient amount of the metal precursor may not be introduced into the thin film prepared above, and when the amount is more than 10 wt%, the amount of the metal precursor is excessive so that the nanowires are arranged in a string. This results in a deviation from the ring structure, so a regular two-dimensional array form cannot be obtained. The precursor has a property of binding to a hydrophilic block rather than a hydrophobic block and binds to a ring-shaped hydrophilic block that is swollen and rearranged.

In the present invention, an alcohol solvent such as ethanol, methanol, butanol, propanol, isopropanol may be used as the solvent mixed with the metal precursor.

In the present invention, the time for contacting the nano ring array and the metal precursor may be 10 minutes to 10 hours, specifically 30 minutes to 2 hours, which may be appropriately adjusted according to the concentration of the metal precursor solution.

Next, the step (e) according to the present invention is to remove the block copolymer by irradiating UV light or oxygen plasma treatment to the monomolecular film formed in the step (d) and at the same time to reduce the metal precursor to the metal nanoparticle structure of the string array To prepare or to reduce the metal precursor using a reducing agent to prepare a metal nanoparticle structure of the string array containing the polymer.

The block copolymer of the formed monomolecular film can be removed by ultraviolet irradiation. In addition, metal ions are reduced during ultraviolet irradiation to form a string array of metal nanoparticle arrays on a substrate. The method of removing the block copolymer by reducing ultraviolet rays and reducing the metal precursor may be applied to metals such as silver and platinum, for example.

In this case, ultraviolet rays may be irradiated for 1 hour to 10 hours at an intensity of 10 to 50 W / cm ² , and specifically, ultraviolet rays having a wavelength of 200 to 300 nm may be irradiated for 1 to 6 hours at an intensity of 25 W / cm ² . Can be. When irradiated with too strong an intensity or for a long time, there is a problem that the metal silver state exhibiting the optimum surface plasmon property cannot be induced, and when irradiated with too weak an intensity or too short, the metal silver precursor is not completely reduced. .

In addition, the formed block copolymer of the monomolecular film may be removed by oxygen plasma treatment. In addition, during the oxygen plasma treatment, metal ions are reduced to form a string array of metal nanoparticle arrays on a substrate. The method of removing the block copolymer and reducing the metal precursor by performing an oxygen plasma treatment can be applied to, for example, gold, zinc oxide, or the like.

At this time, the oxygen plasma may be treated for 10 seconds to 20 minutes at an intensity of 40 to 60 sccm, 100 to 120W, and specifically, may be irradiated for 30 seconds to 10 minutes at an intensity of 110W. If the treatment for too short time there is a problem that the polymer is not completely removed, if the treatment for too long time there is a problem that the metal is agglomerated with each other to ignore the existing structure.

The formed metal precursor may be reduced using a reducing agent. Reducing the metal precursor using a reducing agent can be used for all metals and allows the formation of a string array of metal nanoparticle arrays on which a polymer is not removed. The polymer may be removed in a subsequent process. Gold metal is not reduced when irradiated with ultraviolet light, silver metal is strongly aggregated with each other when the oxygen plasma treatment causes a problem of collapse of the structure. Therefore, it is possible to safely reduce using a reducing agent so as not to influence each other to produce a double metal nanostructure of silver and gold, resulting in the formation of an array of metal nanoparticles in which the polymer is present.

In this case, the metal precursor may be reduced by immersion for 30 seconds to 30 minutes in a reducing agent solution having a concentration of 0.005 M to 0.05 M. As the solvent of the reducing agent solution, a solvent known in the art such as ethanol can be used. The reducing agent is also not particularly limited and may be one or more selected from the group consisting of sodium borohydride (NaBH ₄ ), lithium aluminum hydride (LiAlH ₄ ), sulfur dioxide (SO ₂ ) and hydrogen (H ₂ ) known in the art. You can choose. If the concentration of the solution is too low or the contact time is short, there is a problem that the metal precursor is not sufficiently reduced, if the solution concentration is too high or the contact time is long, due to the strong reducing agent to induce a metal state exhibiting the best surface plasmon properties There is a problem that can not.

The present invention also relates to an array of metal nanoparticle structures produced by the above method.

The metal nanoparticle structure array is characterized in that the nanoscale metal nanoparticles or structures bonded to the metal nanoparticles in the nano ring on the substrate are arranged adjacent to each other in the form of a string.

The metal nanoparticles have an average diameter of about 10 to 40 nm and the spacing between the nanostreams is about 10 to 30 nm.

Specific nanoparticle structures of metals produced by the method according to the invention can be usefully used for chemicals, biomaterials and sensors for diagnosing diseases.

Hereinafter, the present invention will be described in more detail by way of examples. It should be noted, however, that the following examples are illustrative of the invention and are not intended to limit the scope of the invention.

< Example  1> Preparation of Silver Nanoparticle Structure

Polystyrene-block-poly (2-vinylpyridine) (PS-b-P2VP; Mn (PS) = 50000 g / mol, Mw / Mn of asymmetric composition in a solvent in which toluene and tetrahydrofuran were mixed at a weight ratio of 3: 1) = 1.09, purchased from Polymer Source Inc.) to prepare a block copolymer solution having 0.5 wt%. The PS-b-P2VP reverse micelle hexagonal monolayer (coating layer) was prepared by spin coating the block copolymer solution prepared by the above method at 2000 rpm on an n-type (110) silicon wafer.

The monomolecular film prepared by the above method was subjected to solvent annealing at room temperature for 7 hours in a closed vessel saturated with tetrahydrofuran solvent vapor.

The reverse micelle nanowire thin film prepared by the above method was immersed in ethanol for 20 minutes to produce a rearranged nano ring array in which P2VP chains were swollen and exposed to the surface, and at the same time, pores were formed in the center.

The string array nanoring array prepared by the above method was immersed in a silver metal precursor solution having 1.0% by weight of silver metal precursor AgNO ₃ in ethanol solvent for 1 hour.

Irradiated UV light at a wavelength of 254 nm and 25 W / cm ² for more than 3 hours to the monomolecular film in which the silver metal precursor was prepared by the above method was removed to remove the block copolymer and reduce the silver ions. The array was made.

< Example  2> Preparation of Gold Nanoparticle Structure

Except that the metal precursor is 1.0% by weight of HAuCl ₄ and the monomolecular film to which the gold metal precursor is introduced is irradiated with oxygen plasma treatment at an intensity of 50 sccm and 110 W for 1 minute to remove the block copolymer and reduce the gold ions. A string array of gold nanoparticle structure arrays was prepared in the same manner as in Example 1.

< Example  3> Fabrication of Double Metal Nanoparticle Structures of Silver and Gold

Polystyrene-block-poly (2-vinylpyridine) with tetrahydrofuran as solvent (PS-b-P2VP; Mn (PS) = 50000 g / mol, Mw / Mn = 1.09, purchased from Polymer Source Inc.) 0.5% by weight A block copolymer solution having was prepared. PS-b-P2VP monolayer (coating layer) was prepared by spin coating the block copolymer solution prepared by the above method at 2000 rpm on an n-type (1 0 0) silicon waiter.

The monomolecular film prepared by the above method was subjected to solvent annealing at room temperature for 20 minutes in a closed vessel saturated with tetrahydrofuran solvent vapor.

The reverse micelle nanowire thin film prepared by the above method was immersed in ethanol for 20 minutes to produce a rearranged nano ring array in which P2VP chains were swollen and exposed to the surface, and at the same time, pores were formed in the center.

The string array nanoring array prepared by the above method was immersed in a silver metal precursor solution having 1.0% by weight of silver metal precursor AgNO ₃ in ethanol solvent for 30 minutes.

The monomolecular film into which the silver metal precursor prepared by the above method was introduced was immersed in a gold metal precursor solution having 1.0 wt% of the gold metal precursor HAuCl ₄ in an ethanol solvent for 30 minutes.

In the monomolecular film into which the metal precursors of silver and gold prepared by the above method were introduced, immersed in a reducing agent solution having sodium borohydride 0.01 M in an ethanol solvent for 20 minutes to reduce silver and gold ions so that a polymer was present. The double metal nanoparticle structure of was prepared.

< Example  4> Fabrication of Double Metal Nanoparticle Structures of Silver and Gold

A double metal nanoparticle structure of silver and gold in a string arrangement in which a polymer is present was prepared in the same manner as in Example 3 except that the order of immersion in the silver and gold metal precursor solution was reversed.

< Experimental Example  1> Surface analysis of thin film

Observed by atomic force microscopy (AFM) to analyze the surface of the structure from the reverse micelle monolayer prepared in Example 1 according to the present invention to the array of silver nanoparticles of the string array, and the results are shown in FIGS. 7 is shown.

The silver nanoparticle structure of the string array prepared in Example 1 was observed under an atomic force microscope (see FIG. 1).

Observation of the surface of the block copolymer template thin film prepared in Example 1 with an atomic force microscope revealed a block copolymer reverse micelle arranged at a diameter of about 30 nm and an interval of about 40 nm (see FIG. 2).

The block copolymer template prepared in Example 1 was rearranged through a solvent annealing process under an atomic force microscope, and the diameter of the bright nanowire structure was about 50 nm, and each nanowire was about. It appeared to be arranged at intervals of 25 nm (see FIG. 3).

A nanowire structure of a string array prepared by immersing the reverse micelle nanowire thin film prepared in Example 1 in ethanol was observed by atomic force microscopy. As a result, nanorings having a diameter of about 60 nm and pores of about 20 nm were observed. This was observed to form a string array connected to each other (see Fig. 4).

As a result of observing the thin film in which the silver precursor is introduced by immersing the string array nano ring array prepared in Example 1 into the metal precursor solution by atomic force microscopy, the ring which was made continuously was swelled more by the introduction of the silver precursor. It appears to maintain the string arrangement. This was more pronounced when observed under high magnification atomic force microscopy (see Figures 5 and 6).

A nanoparticle structure in which the block copolymer was removed and silver ions were reduced to metal by irradiation with ultraviolet rays was irradiated with ultraviolet rays to the nanoring thin film in which the metal precursor prepared in Example 1 was introduced. It was found that about 25 nm of silver nanoparticles maintained this arrangement, with a portion consisting of two to three nanoparticles assembled (see FIG. 7).

< Experimental Example  2> X-ray photoelectron spectroscopy From the spectrum  Observation of the reduction of metal precursors

As described in Example 1, after the silver precursor was immersed in the silver precursor solution and the UV light was irradiated to remove the block copolymer of the thin film and induced reduction with silver metal, the X-ray photoelectron spectroscopy was used. The spectra obtained were compared.

The string array before and after reduction of the metal precursor prepared in Example 1 is the broad spectrum of the X-ray photoelectron spectrometer of the nanoparticle structure (see FIG. 8) and the silver nanoparticle structure of the string array before and after reduction of the metal precursor prepared in Example 1 The high resolution spectra of silver metals analyzed by X-ray photoelectron spectroscopy were measured (see FIG. 9). As a result, it can be observed that after the silver precursor was reduced to the silver metal, the characteristic peak of the spectrum increased more than three times in size, and the position shifted toward a higher binding energy.

< Experimental Example  3> Surface analysis of thin film

Observed by atomic force microscopy (AFM) to analyze the surface of the structure from the reverse micelle monolayer prepared in Example 2 according to the present invention to the array of gold nanoparticles of the string array, the results are shown in Figures 10 to 12 It was.

As a result of observing the thin film on which the gold precursor was introduced by immersing the string array nano ring array prepared in Example 2 into the metal precursor solution by atomic force microscopy, the ring which was continuously formed was swelled more by the introduction of the gold precursor. It was shown that the string array was maintained (see FIG. 10).

As a result of observing the gold nanoparticle structure in which the block copolymer was removed and the gold ions were reduced to the metal by oxygen plasma treatment to the nanoarray thin film of the string array into which the metal precursor prepared in Example 2 was introduced, using an atomic force microscope, It was shown that two to three nanoparticles form an aggregated ring arrangement. This was more clearly observed when observed with high magnification atomic force microscopy (see FIGS. 11 and 12).

< Experimental Example  4> Surface analysis of thin film

Observed by atomic force microscopy (AFM) to analyze the surface of the structure from the block copolymer monomolecular film prepared in Examples 3 to 4 according to the present invention from the string array of double metal nanoparticle arrays of silver and gold. 13 to 17 and 19 to 20 are shown.

As a result of observing the surface of the block copolymer template thin film prepared in Example 3 with an atomic force microscope, a reverse copolymer and a block copolymer in the form of chain were observed due to the influence of the cosolvent (see FIG. 13).

The block copolymer template prepared in Example 3 was rearranged through a solvent annealing process in reverse micelle nanowire thin film under atomic force microscope, and the diameter of the bright nanowire structure was about 30 nm and each nanowire was about It appears to be arranged at intervals of 20 nm. It was also observed that each of the nanowires were not connected to each other and aligned without disconnection (see FIG. 14).

A nanowire array of a string array prepared by immersing the reverse micelle nanowire thin film prepared in Example 3 in ethanol was observed by atomic force microscopy, and found that the nanoring had a diameter of about 60 nm and a pore of about 20 nm. This was observed to form a string array connected to each other (see Fig. 15).

As a result of observing the thin film in which the silver and gold precursors were introduced by sequentially immersing the string array nanoring array prepared in Example 3 in the silver metal precursor and the gold metal precursor solution, the ring formed continuously was silver Although the precursor was introduced and swelled but appeared to maintain the string arrangement as a whole, it was observed that the metal precursors aggregated and gathered in many parts (see FIG. 16).

The result of observing the double metal nanoparticle structure of silver and gold in which the silver and gold ions were reduced to the metal by immersing the string array nano ring array into which the metal precursor prepared in Example 3 was immersed in a reducing agent solution was observed by atomic force microscopy. However, nanoparticles with a diameter of about 20 nm are arranged, but in many parts, aggregated metals are found to be out of alignment (see FIG. 17).

The thin film in which the gold and silver precursors were introduced by sequentially immersing the string array nanoring array prepared in Example 4 in the gold metal precursor and the silver metal precursor solution was observed under an atomic force microscope. As a result, the ring, which was formed continuously, was swelled with the introduction of silver and gold precursors, but maintained the string arrangement as a whole (see FIG. 19).

The nano-ring array of the string array into which the metal precursor prepared in Example 4 was introduced was immersed in a reducing agent solution, and the gold and silver double metal nanoparticle structures in which gold and silver ions were reduced to metals were observed by atomic force microscopy. As a result, it was shown that nanoparticles having a diameter of about 20 nm maintain the arrangement and form a ring arrangement in which two or three nanoparticles are assembled (see FIG. 20).

< Experimental Example  5> Gold and silver precursor solution Immersion  Localized surfaces of silver and gold double metal nanoparticle structures fabricated in a different order Plasmon  resonance( LSPR Property measurement

Local surface plasmon resonance (LSPR) properties of the structure ranging from the block copolymer monomolecular film prepared in Examples 3 to 4 according to the present invention to the array of double metal nanoparticles of silver and gold in the string array were measured, and the results are shown in FIG. 18. And FIG. 21.

When the local surface plasmon resonance properties of the gold and silver double metal nanoparticle structures prepared in Examples 3 and 4 were measured, silver-specific local surface plasmon resonance characteristic peaks of 400 to 450 nm and gold-specific local surface plasmons It was observed that local surface plasmon resonance peaks of the gold and silver double metal nanoparticle structures exist between the resonance characteristic peaks of 500 to 530 nm. The results indicated that the two metals were present in a mixed state rather than in each case (see FIGS. 18 and 21).

Claims (20)

(a) applying a block copolymer solution including a hydrophilic block and a hydrophobic block to a substrate to prepare a block copolymer reverse micelle hexagonal monolayer;
(b) contacting the monomolecular film with a solvent gas using a saturated solvent gas for 10 minutes to 8 hours to prepare a nanowire thin film in which the block copolymers are rearranged in a string form adjacent to each other; And
(c) immersing the nanowire thin film rearranged in the form of a string in a solvent for selectively dissolving a hydrophilic block to prepare a string array of nanoring arrays in which a hydrophilic block is swollen onto the surface and a pore is formed at the center thereof.
Method of manufacturing a nano-ring array of string array with pores formed in the center comprising a.
The method of claim 1,
The hydrophilic block is at least one member selected from the group consisting of polyvinylpyridine, polyethylene oxide, polyacrylic acid, polymethacrylic acid, polyvinyl alcohol, polyacrylamide, and polystyrene sulfonic acid polymer. Method of manufacturing a nano-ring array of string array.
The method of claim 1,
The hydrophobic block is at least one member selected from the group consisting of polystyrene, polyolefin, polyalkylacrylate, polyisoprene, polybutadiene, polysiloxane, polyimidazole, polylactone and polylactide polymer Method of manufacturing a nano-ring array of string array.
The method of claim 1,
The solution of step (a) is 0.1 to 1% by weight of the block copolymer, characterized in that the method of producing a nano-ring array of string array with pores formed in the center.
The method of claim 1,
The solution of step (a) comprises at least one selected from the group consisting of a hydrophilic block and a solvent which selectively dissolves a co-solvent having affinity with the hydrophobic block and the hydrophobic block. Method of manufacturing a nano ring array.
The method of claim 5,
A method for producing a nano-ring array comprising 0.2 to 0.7 parts by weight of a hydrophilic block and a cosolvent having an affinity with a hydrophobic block with respect to 1 part by weight of a solvent for selectively dissolving the hydrophobic block.
The method of claim 1,
The method of manufacturing a nano-ring array of string array with pores formed in the center, characterized in that the step (a) in the block copolymer solution is applied to the substrate using a spin coating method.
delete The method of claim 1,
The solvent is a method of producing a nano-ring array of string array with pores formed in the center, characterized in that the co-solvent having affinity with the hydrophilic block and hydrophobic block.
The method of claim 1,
A solvent for selectively dissolving the hydrophilic block of step c) is an alcohol solvent or an acidic solvent.
The method of claim 1,
The method of manufacturing a nano-ring array of the string array with pores formed in the center, characterized in that the contact of step c) is carried out for 30 seconds to 2 hours.
Nano ring array of string array with pores formed in the center according to the method of claim 1.
(a ') preparing a nano-ring array of string array having pores formed in the center by the method of claim 1;
(d) contacting the nano ring array with a metal precursor solution; And
(e) performing at least one selected from ultraviolet irradiation, oxygen plasma treatment and reducing agent treatment.
Method of manufacturing a metal nanoparticle structure array of the string array comprising a.
The method of claim 13,
And the metal precursor is at least one selected from the group consisting of nitrates, sulfates, carbonates, acetates, bromide, chlorides, fluorides, hydroxides and hydrates of metals.
The method of claim 13,
The metal precursor solution is a method of producing a string array of metal nanoparticle structure array, characterized in that it comprises 0.1 to 10% by weight of the metal precursor.
The method of claim 13,
The ultraviolet irradiation is a method for producing a string array of metal nanoparticle structure array, characterized in that for 1 to 10 hours treatment at an intensity of 10 to 50 W / cm ² .
The method of claim 13,
The oxygen plasma treatment is a method for producing a string array of metal nanoparticle structure array, characterized in that the treatment for 10 seconds to 20 minutes at an intensity of 40 to 60 sccm, 100 to 120 W.
The method of claim 13,
The reducing agent treatment is a method for producing a string array of metal nanoparticle structure array, characterized in that for 30 seconds to 30 minutes to treat a reducing agent solution of 0.005 to 0.05 M concentration.
The method of claim 13,
The reducing agent is a string array metal nanoparticle structure, characterized in that at least one selected from the group consisting of sodium borohydride (NaBH ₄ ), lithium aluminum hydride (LiAlH ₄ ), sulfur dioxide (SO ₂ ) and hydrogen (H ₂ ). Method of making an array.
An array of metal nanoparticle structures in a string arrangement made according to the method of claim 13.

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