KR20230037904A - Manufacturing mehtod of Large h-BNNS dispersion solution by solvothermal method - Google Patents
Manufacturing mehtod of Large h-BNNS dispersion solution by solvothermal method Download PDFInfo
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- 239000006185 dispersion Substances 0.000 title claims abstract description 60
- 238000004729 solvothermal method Methods 0.000 title claims abstract description 21
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 18
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 claims abstract description 38
- 229910052582 BN Inorganic materials 0.000 claims abstract description 37
- 239000002135 nanosheet Substances 0.000 claims abstract description 25
- 239000002904 solvent Substances 0.000 claims abstract description 23
- 238000000034 method Methods 0.000 claims abstract description 19
- 238000010438 heat treatment Methods 0.000 claims abstract description 8
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 claims description 15
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 claims description 9
- XNLICIUVMPYHGG-UHFFFAOYSA-N pentan-2-one Chemical compound CCCC(C)=O XNLICIUVMPYHGG-UHFFFAOYSA-N 0.000 claims description 6
- XBDQKXXYIPTUBI-UHFFFAOYSA-M Propionate Chemical compound CCC([O-])=O XBDQKXXYIPTUBI-UHFFFAOYSA-M 0.000 claims description 3
- KXKVLQRXCPHEJC-UHFFFAOYSA-N acetic acid trimethyl ester Natural products COC(C)=O KXKVLQRXCPHEJC-UHFFFAOYSA-N 0.000 claims description 3
- 230000017525 heat dissipation Effects 0.000 abstract description 6
- 238000009830 intercalation Methods 0.000 abstract description 4
- 239000000203 mixture Substances 0.000 abstract description 2
- 238000002203 pretreatment Methods 0.000 abstract 1
- 239000000243 solution Substances 0.000 description 37
- 239000010410 layer Substances 0.000 description 12
- 230000000052 comparative effect Effects 0.000 description 10
- 239000000463 material Substances 0.000 description 6
- 239000011229 interlayer Substances 0.000 description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- 239000011259 mixed solution Substances 0.000 description 4
- 230000003287 optical effect Effects 0.000 description 4
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical group [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 3
- 238000004630 atomic force microscopy Methods 0.000 description 3
- 238000005229 chemical vapour deposition Methods 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
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- 239000006228 supernatant Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 2
- 238000002835 absorbance Methods 0.000 description 2
- 238000013019 agitation Methods 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 125000000524 functional group Chemical group 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 229910021389 graphene Inorganic materials 0.000 description 2
- 229910002804 graphite Inorganic materials 0.000 description 2
- 239000010439 graphite Substances 0.000 description 2
- 230000002687 intercalation Effects 0.000 description 2
- 239000002086 nanomaterial Substances 0.000 description 2
- 125000004433 nitrogen atom Chemical group N* 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 238000004626 scanning electron microscopy Methods 0.000 description 2
- 239000002356 single layer Substances 0.000 description 2
- 238000005411 Van der Waals force Methods 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
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- 238000010586 diagram Methods 0.000 description 1
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- 238000005516 engineering process Methods 0.000 description 1
- 238000004299 exfoliation Methods 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
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- 238000010297 mechanical methods and process Methods 0.000 description 1
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- 230000035939 shock Effects 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
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- 238000009210 therapy by ultrasound Methods 0.000 description 1
- 238000001132 ultrasonic dispersion Methods 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/06—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron
- C01B21/064—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron with boron
- C01B21/0648—After-treatment, e.g. grinding, purification
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J19/00—Chemical, physical or physico-chemical processes in general; Their relevant apparatus
- B01J19/08—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor
- B01J19/10—Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor employing sonic or ultrasonic vibrations
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/06—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron
- C01B21/064—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron with boron
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/20—Particle morphology extending in two dimensions, e.g. plate-like
- C01P2004/24—Nanoplates, i.e. plate-like particles with a thickness from 1-100 nanometer
Abstract
Description
본 발명은 육방정계 질화붕소 나노시트 분산용액의 제조방법에 관한 것으로, 더욱 상세하게는 우수한 분산 안정성, 1㎛ 이상의 면방향 크기(lateral size), 5nm 이하의 두께를 가지는 용매열을 이용한 대면적 육방정계 질화붕소 분산용액의 제조방법에 관한 것이다. The present invention relates to a method for preparing a dispersion of hexagonal boron nitride nanosheets, and more particularly, to a large-area hexagonal solution using solvent heat having excellent dispersion stability, a lateral size of 1 μm or more, and a thickness of 5 nm or less. It relates to a method for producing a crystalline boron nitride dispersion solution.
2차원 나노구조 재료는 일정한 평면형태를 가지며 두께가 원자 한층 또는 몇 층으로 이루어진 소재로, 화학, 재료 분야의 연구가 가장 활발한 연구 분야 중 하나로 손꼽히고 있으며, 전자, 기계 및 생명공학 분야로의 접목을 통하여 연구 주제가 다변화되고 있는 분야이다.Two-dimensional nanostructure materials are materials with a certain plane shape and a thickness of one atom or several layers, and research in the fields of chemistry and materials is considered one of the most active research fields, and is grafted into the fields of electronics, machinery, and biotechnology. This is a field in which research topics are diversifying.
대표적인 2차원 나노구조 재료로는 그래핀, 질화붕소 등을 수 있는데, 이중에서 질화붕소는 BN의 화학식을 가지고, 보론 원자와 질소 원자가 평면 2차원 육각형 구조를 이루고 있으며, 흑연과 비슷한 육방정계 구조를 갖고 있어 화학적, 물리적 성질이 흑연과 비슷하여, 물리적, 화학적 안정성이 높은 물질이다.Representative two-dimensional nanostructure materials include graphene and boron nitride. Among them, boron nitride has a chemical formula of BN, boron atoms and nitrogen atoms form a planar two-dimensional hexagonal structure, and a hexagonal structure similar to graphite. It has chemical and physical properties similar to graphite, so it is a material with high physical and chemical stability.
이러한 육방정계 질화붕소(hexagonal boron nitride : h-BN)는 불활성 분위기에서는 최대 3000℃까지 안정하며, 스테인레스 스틸 정도의 높은 열전도율이 있어 열충격 저항성이 크고, 1500℃ 정도의 급가열, 급냉각을 반복하여도 균열이나 파손이 없다. 그리고 고온 윤활성 및 내식성이 대단히 우수하다. 또한, 전기 저항값이 월등히 높은데, 특히 고온에서의 전기 저항값의 변화가 적어 넓은 온도 범위에서 전기절연재료로 사용할 수 있으며 전계를 가하면 자외선을 방출하는 특성이 있다. 뿐만 아니라, h-BN은 그래핀과 마찬가지로 모든 가스와 액체에 대해서 불침투성을 보이며, 투명하며 보론 원자와 질소 원자가 그물처럼 연결된 육각형 벌집 구조의 공간적 여유로 인해 신축성이 뛰어나다. 이러한 h-BN의 특이한 구조와 물성은 반도체 재료의 절연체 및 자외선 발생장치, 배리어 필름으로 응용될 수 있다.Hexagonal boron nitride (h-BN) is stable up to 3000℃ in an inert atmosphere, has high thermal conductivity as high as stainless steel, and has high thermal shock resistance. No cracks or breaks either. In addition, it has excellent lubricity and corrosion resistance at high temperatures. In addition, it has a very high electrical resistance value, and in particular, it can be used as an electrical insulating material in a wide temperature range because the change in electrical resistance value is small at high temperatures, and has a characteristic of emitting ultraviolet rays when an electric field is applied. In addition, h-BN, like graphene, is impervious to all gases and liquids, is transparent, and has excellent elasticity due to the spatial margin of the hexagonal honeycomb structure in which boron atoms and nitrogen atoms are connected like a net. These unique structures and physical properties of h-BN can be applied as insulators of semiconductor materials, ultraviolet ray generators, and barrier films.
최근 나노 기술에 대한 수요와 관심이 증대되면서 h-BN도 나노시트, 나노튜브와 같은 형태로 얻기 연구가 진행되고 있다. 현재 육방정계 질화붕소 나노시트(hexagonal boron nitride nanosheet : h-BNNS)를 제조하는 방법으로는 기계적 박리, 화학기상증착(Chemical Vapor Deposition : CVD), 질화붕소 층간 화합물 방법 등이 있다.Recently, as demand and interest in nanotechnology increase, research on obtaining h-BN in the form of nanosheets and nanotubes is being conducted. Currently, methods for producing hexagonal boron nitride nanosheets (h-BNNS) include mechanical exfoliation, chemical vapor deposition (CVD), and boron nitride interlayer compound methods.
먼저, 기계적 방법은 다층의 h-BN를 용매 내에서 초음파 처리를 통해 떼어내는 방법으로, 가장 간단하게 h-BNNS를 제조할 수 있는 방법이다. 그러나 이러한 방법은 대량 생산에 어려움이 있으며, 소수층으로의 박리가 어려워 수 nm의 두께를 갖는 h-BNNS를 제조할 수 없다는 단점이 있다.First, the mechanical method is a method in which multiple layers of h-BN are separated through ultrasonic treatment in a solvent, and is the simplest method for preparing h-BNNS. However, this method has disadvantages in that it is difficult to mass-produce, and it is difficult to manufacture h-BNNS having a thickness of several nm because it is difficult to exfoliate into a few layers.
CVD 방법은 기판 위에 촉매 금속을 증착하여 얇은 금속 막을 형성한 후 고온에서 보론과 질소가 포함된 기체를 흘려준 뒤, 냉각시켜 금속 막 위에 형성된 h-BNNS를 얻는 방법으로, 공정 온도가 매우 높으므로, 대면적 및 가격면에서 불리한 단점이 있다. The CVD method deposits a catalytic metal on a substrate to form a thin metal film, flows a gas containing boron and nitrogen at a high temperature, and then cools it to obtain h-BNNS formed on the metal film. Since the process temperature is very high, , there are disadvantages in terms of large area and price.
질화붕소 층간 화합물 방법으로는, h-BN에 히드록시기와 같은 작용기를 결합시켜 층간 인력을 완화하고, 작용기와 용매와의 친화성을 향상시킨 분산액을 제조하여 단일층의 질화붕소를 제조하는 방법이나, 제조된 단일층 질화붕소의 수율이 낮은 단점이 있다.As the boron nitride interlayer compound method, a method of preparing a single layer of boron nitride by preparing a dispersion solution in which a functional group such as a hydroxyl group is bonded to h-BN to relieve the interlayer attraction and improving the affinity between the functional group and the solvent, There is a disadvantage in that the yield of the produced single-layer boron nitride is low.
한편, h-BNNS는 수직방향보다 수평방향의 열전도도가 수십배에 다달할 정도로 높아 방열 패드 등으로 활용되고 있다.On the other hand, h-BNNS is used as a heat dissipation pad because the thermal conductivity in the horizontal direction is several tens of times higher than that in the vertical direction.
그러나 고품질의 방열 패드로 활용하기 위해서는 대면적의 면방향 크기가 요구되는바, 종래 게시된 방법으로 제조되는 h-BNNS 분산용액은 낮은 분산성을 보임은 물론, 수십 nm 정도의 작은 시트 크기를 가지며, 그 두께는 10nm 이상으로, h-BNNS의 높은 수평방향 열전도도를 활용하기 어렵다는 문제가 있었다. However, in order to be used as a high-quality heat dissipation pad, a large area in the direction of the surface is required, and the h-BNNS dispersion prepared by the conventionally published method shows low dispersibility as well as a small sheet size of about tens of nm. , the thickness is more than 10 nm, and there was a problem that it was difficult to utilize the high horizontal thermal conductivity of h-BNNS.
따라서, 본 발명의 목적은 우수한 분산 안정성을 가지며, 1㎛ 이상의 면방향 크기, 5nm 이하의 두께를 가지는 용매열 방법을 이용한 대면적 육방정계 질화붕소 나노시트 분산용액의 제조방법을 제공하는 데 있다.Accordingly, an object of the present invention is to provide a method for preparing a large-area hexagonal boron nitride nanosheet dispersion solution using a solvothermal method having excellent dispersion stability, a surface direction size of 1 μm or more and a thickness of 5 nm or less.
본 발명의 다른 목적은 고품질의 대면적 육방정계 질화붕소 나노시트 분산용액을 안전하고, 경제적인 공정으로 대량 제조할 수 있도록 하는 용매열 방법을 이용한 대면적 육방정계 질화붕소 나노시트 분산용액의 제조방법을 제공하는 데 있다.Another object of the present invention is a method for producing a large-area hexagonal boron nitride nanosheet dispersion solution using a solvothermal method to mass-produce a high-quality large-area hexagonal boron nitride nanosheet dispersion solution in a safe and economical process. is to provide
상기한 목적을 달성하기 위한 본 발명의 대면적 육방정계 질화붕소 나노시트 분산용액의 제조방법은, 육방정계 질화붕소(h-BN)와 용매를 혼합하고, 가열 처리하여 육방정계 질화붕소의 층간에 용매를 인터칼레이션(intercalation)하는 전처리 단계와, 상기 전처리된 용액에 외부 에너지를 공급하여 육방정계 질화붕소를 박리함으로써, 대면적 육방정계 질화붕소 나노시트 분산용액을 제조하는 분산 단계를 포함하는 것을 특징으로 한다.In order to achieve the above object, the method for preparing a large-area hexagonal boron nitride nanosheet dispersion solution of the present invention is a mixture of hexagonal boron nitride (h-BN) and a solvent, followed by heat treatment to form a gap between layers of hexagonal boron nitride. A pretreatment step of intercalating a solvent, and a dispersion step of preparing a large-area hexagonal boron nitride nanosheet dispersion solution by exfoliating hexagonal boron nitride by supplying external energy to the pretreated solution. to be characterized
상기 용매는 에틸 아세테이트(ethyl acetate), 메틸 아세테이트(methyl acetate), 메틸에틸케톤(methyl ethyl ketone), 메틸프로틸케톤(methyl propyl ketone) 중 1종 이상인 것을 특징으로 한다.The solvent is characterized in that at least one of ethyl acetate, methyl acetate, methyl ethyl ketone, and methyl propyl ketone.
상기 가열 처리는, 180∼220℃에서 10~48시간 수행하는 것을 특징으로 한다.The heat treatment is characterized in that it is performed at 180 to 220 ° C. for 10 to 48 hours.
상기 분산용액 내 육방정계 질화붕소 나노시트는 평균 면방향 크기(lateral size)가 1㎛ 이상이고, 두께가 5nm 이하인 것을 특징으로 한다.The hexagonal boron nitride nanosheets in the dispersion solution are characterized in that the average lateral size is 1 μm or more and the thickness is 5 nm or less.
상기 분산용액 내 육방정계 질화붕소 나노시트는 1~3개의 층으로 구성됨을 특징으로 한다.The hexagonal boron nitride nanosheet in the dispersion solution is characterized in that it is composed of 1 to 3 layers.
상기 외부 에너지는 초음파인 것을 특징으로 한다.The external energy is characterized in that ultrasonic waves.
본 발명의 용매열 방법을 이용한 대면적 육방정계 질화붕소 나노시트 분산용액의 제조방법에 의하면, 분산 안정성이 우수하고, 큰 면방향 크기와 얇은 두께를 갖는 대면적 육방정계 질화붕소 나노시트 분산용액의 제조가 가능하여 산업 전반에 걸쳐 그 활용도를 높일 수 있다는 장점이 있다. 특히, 육방정계 질화붕소 나노시트의 높은 수평방향 열전도도를 이용한 방열 패드의 제조가 가능하다는 장점이 있다.According to the preparation method of the large-area hexagonal boron nitride nanosheet dispersion solution using the solvothermal method of the present invention, the dispersion stability is excellent, and the large-area hexagonal boron nitride nanosheet dispersion solution having a large surface direction size and thin thickness It has the advantage that it can be manufactured and its utilization can be increased throughout the industry. In particular, there is an advantage in that it is possible to manufacture a heat dissipation pad using the high horizontal thermal conductivity of the hexagonal boron nitride nanosheet.
도 1은 본 발명에 의한 대면적 h-BNNS 분산용액 제조방법을 나타낸 개념도.
도 2는 본 발명에 의한 실시예 1 및 비교예 1의 광학사진.
도 3은 본 발명에 의한 실시예 1의 용매열 공정 전후의 XRD 분석 결과를 나타낸 그래프.
도 4는 본 발명에 의한 실시예 1과 비교예 1의 SEM 및 AFM 분석을 통한 분산 결과를 나타낸 도면.
도 5는 본 발명에 의한 실시예 1과 비교예 1의 UV-Vis 광학 측정기로부터 얻어진 흡광도를 나타낸 그래프.1 is a conceptual diagram showing a method for preparing a large-area h-BNNS dispersion solution according to the present invention.
Figure 2 is an optical photograph of Example 1 and Comparative Example 1 according to the present invention.
Figure 3 is a graph showing the XRD analysis results before and after the solvothermal process of Example 1 according to the present invention.
4 is a view showing dispersion results through SEM and AFM analysis of Example 1 and Comparative Example 1 according to the present invention.
Figure 5 is a graph showing the absorbance obtained from the UV-Vis optical measuring instrument of Example 1 and Comparative Example 1 according to the present invention.
이하, 본 발명을 상세히 설명한다.Hereinafter, the present invention will be described in detail.
본 발명의 가장 큰 특징은 도 1과 같이, 용매열 공정을 통해 육방정계 질화붕소(h-BN)를 전처리하고, 이에 외부 에너지를 공급하여 분산함으로써, 분산 안정도가 우수하고, 면방향 크기(lateral size)가 1㎛ 이상이며, 두께가 5nm 이하인 대면적 h-BNNS 분산용액을 제조하는 데 있다.As shown in FIG. 1, the biggest feature of the present invention is that hexagonal boron nitride (h-BN) is pretreated through a solvothermal process and dispersed by supplying external energy thereto, so that the dispersion stability is excellent and the lateral size (lateral size) is more than 1 μm, and the thickness is less than 5 nm to prepare a large-area h-BNNS dispersion solution.
즉, 종래의 제조방법에 의하면 대면적의 육방정계 질화붕소 나노시트(h-BNNS)를 제조하는 데 어려움이 있어, h-BNNS의 높은 수평방향 열전도도를 활용하기에 어려움이 있었으나, 본원발명은 분산 안정도가 우수한 대면적의 h-BNNS를 제조할 수 있음으로써, 산업 전반에 걸쳐 활용도를 높일 수 있고, 특히 우수한 열전도도를 갖는 방열 패드의 제조가 가능하다는 데 특징이 있는 것이다.That is, according to the conventional manufacturing method, there was difficulty in manufacturing a large-area hexagonal boron nitride nanosheet (h-BNNS), and it was difficult to utilize the high horizontal thermal conductivity of the h-BNNS, but the present invention By being able to manufacture large-area h-BNNS with excellent dispersion stability, it is possible to increase utilization throughout the industry, and in particular, it is possible to manufacture a heat dissipation pad having excellent thermal conductivity.
이를 위한 본 발명의 용매열 방법을 이용한 대면적 h-BNNS 분산용액의 제조방법은, h-BN과 용매를 혼합하고, 가열 처리하여 h-BN의 층간에 용매를 인터칼레이션하는 전처리 단계와, 상기 전처리된 용액에 외부 에너지를 공급하여 h-BN을 박리함으로써, 대면적 h-BNNS 분산용액을 제조하는 분산 단계를 포함하는 것을 특징으로 한다.The method for preparing a large-area h-BNNS dispersion solution using the solvothermal method of the present invention for this purpose includes a pretreatment step of mixing h-BN and a solvent and performing heat treatment to intercalate the solvent between layers of h-BN; and a dispersion step of preparing a large-area h-BNNS dispersion solution by exfoliating the h-BN by supplying external energy to the pretreated solution.
먼저, h-BN과 용매를 혼합한다. 상기 h-BN의 효율적인 전처리를 위하여 혼합용액을 20~30시간 정도 교반, 혼합한다. First, h-BN and a solvent are mixed. For efficient pretreatment of the h-BN, the mixed solution is stirred and mixed for about 20 to 30 hours.
이때, 상기 h-BN은 벌크형의 h-BN power을 의미한다. At this time, the h-BN means bulk type h-BN power.
상기 용매로는 에틸 아세테이트(ethyl acetate), 메틸 아세테이트(methyl acetate), 메틸에틸케톤(methyl ethyl ketone), 메틸프로틸케톤(methyl propyl ketone) 중 1종 이상을 사용함이 바람직하다. 이는 상기 h-BN의 층간 반데르발스 결합을 약화시키기 위해 층간에 용매의 인터칼레이션이 요구되는바, 상기한 용매들이 그 효율이 가장 우수하기 때문이다.It is preferable to use at least one of ethyl acetate, methyl acetate, methyl ethyl ketone, and methyl propyl ketone as the solvent. This is because solvent intercalation is required between the layers to weaken the van der Waals bond between the layers of the h-BN, and the above solvents are the most efficient.
이때, 상기 h-BN의 투입량은 혼합액의 농도가 0.1~10mg/ml이 되도록 하는 것이 바람직한바, 이는 원활한 전처리 및 분산 안정도를 위함이다. At this time, the amount of h-BN added is preferably such that the concentration of the mixed solution is 0.1 to 10 mg/ml, which is for smooth pretreatment and dispersion stability.
그리고 이를 용매열 공정으로 처리한다. 상기 용매열 공정이란 상기 혼합용액을 150~250℃에서 10~48시간 가열 처리하는 것을 의미한다. 즉, 상기 혼합용액 내 용매를 가열함으로써, 가열된 용매가 h-BN의 층간에 인터칼레이션되어 h-BN 층간의 반데르 발스 힘에 의한 결합력을 약화시키는 것이다. And it is treated with a solvothermal process. The solvothermal process means heating the mixed solution at 150 to 250 ° C. for 10 to 48 hours. That is, by heating the solvent in the mixed solution, the heated solvent is intercalated between the h-BN layers to weaken the bonding force between the h-BN layers due to van der Waals force.
여기서, 상기 반응온도가 150℃ 미만일 경우 용매열 공정에 의한 전처리 효과가 나타나지 않으며, 250℃를 초과할 경우 공급되는 에너지원의 손실 및 고온고압에 설계된 반응기의 필요로 인한 상용화에 문제점이 있다. 아울러, 상기 반응시간이 10시간 미만인 경우 용매열 공정에 의한 전처리 효과가 나타나지 않고, 48시간을 초과할 경우 경제적이지 못하기 때문이다.Here, when the reaction temperature is less than 150 ° C., the pretreatment effect by the solvothermal process does not appear, and when it exceeds 250 ° C., there is a problem in commercialization due to the loss of energy source supplied and the need for a reactor designed for high temperature and high pressure. In addition, when the reaction time is less than 10 hours, the pretreatment effect by the solvothermal process does not appear, and when the reaction time exceeds 48 hours, it is not economical.
본 발명에서 상기 용매열 공정은 밀페형 또는 오픈형 반응기에서 모두 수행될 수 있는 것으로, 반응기의 종류를 제한하지 않는다.In the present invention, the solvothermal process can be performed in either a closed or open reactor, and the type of reactor is not limited.
다음으로, 상기 h-BN의 층간 결합이 약화되면, 상기 용액에 외부 에너지를 공급하여 약화된 층간 결합을 분리시킴으로써, h-BN의 표면 손상이나 고유 물성의 손상없이 대면적의 h-BNNS 분산용액을 제조한다.Next, when the interlayer bonding of the h-BN is weakened, external energy is supplied to the solution to separate the weakened interlayer bonding, thereby providing a large-area h-BNNS dispersion solution without damaging the surface or inherent properties of the h-BN. to manufacture
이때, 상기 외부 에너지는 자력교반, 물리교반, 초음파, 믹서, 고압분사, 볼밀, 쓰리롤밀 및 이들의 조합으로 이루어진 군에서 선택되는 것일 수 있으나, 가장 바람직하게는 초음파를 가하는 것으로, 이를 통해 나노시트의 손상 없어 대면적의 h-BNNS 분산용액을 제조하는 것이다.At this time, the external energy may be selected from the group consisting of magnetic agitation, physical agitation, ultrasonic waves, mixers, high-pressure injection, ball mills, three-roll mills, and combinations thereof, but most preferably, ultrasonic waves are applied, through which nanosheets To prepare a large-area h-BNNS dispersion solution without damaging the
상기 초음파 분산의 조건은 이 기술이 속하는 분야에서 공지된 정도로 실시하면 족한바, 예시적으로 20~80kHz의 주파수로 30분~5시간 실시할 수 있다. The condition of the ultrasonic dispersion is sufficient if it is performed to a degree known in the field to which this technology belongs, and may be exemplarily carried out for 30 minutes to 5 hours at a frequency of 20 to 80 kHz.
또한, 추가적으로 상기 대면적 h-BNNS의 분산용액을 원심분리하여 상등액만을 수득할 수도 있는 것으로, 그 추가 실시를 제한하지 않는다. In addition, only the supernatant may be obtained by additionally centrifuging the large-area h-BNNS dispersion solution, and the additional implementation is not limited.
상기와 같이 h-BN의 전처리 후, 외부 에너지를 공급하여 분산 처리하면, 평균 면방향 크기가 1㎛ 이상이고, 1~3개의 층으로 이루어져 그 두께가 5nm 이하인 대면적 h-BNNS 분산용액을 제조할 수 있다.After pretreatment of h-BN as described above, when external energy is supplied and dispersed, a large-area h-BNNS dispersion solution having an average surface direction size of 1 μm or more and 1 to 3 layers with a thickness of 5 nm or less is prepared. can do.
또한, 대면적 h-BNNS 분산용액의 용매를 모두 제거할 경우 대면적의 h-BNNS만을 수득할 수도 있다.In addition, when all the solvents of the large-area h-BNNS dispersion solution are removed, only the large-area h-BNNS may be obtained.
이러한 대면적의 h-BNNS는 수평방향으로의 높은 열전도도를 활용할 수 있으므로, 고품질의 방열 패드 제작이 가능해진다.Since such a large-area h-BNNS can utilize high thermal conductivity in the horizontal direction, it is possible to manufacture a high-quality heat dissipation pad.
이하, 본 발명을 구체적인 실시예를 통해 상세히 설명한다.Hereinafter, the present invention will be described in detail through specific examples.
(실시예 1)(Example 1)
h-BN power(평균입경 10㎛)와 용매인 ethyl acetate을 반응기에 투입하고, 이를 1일간 200rpm의 속도로 교반, 혼합하였다. 이때, 그 농도는 0.66mg/ml였다. 그리고 이 용액을 200℃의 온도로 24시간 동안 가열 처리하였다.h-BN power (average particle diameter of 10 μm) and ethyl acetate as a solvent were put into a reactor, and they were stirred and mixed at a speed of 200 rpm for one day. At this time, the concentration was 0.66mg/ml. Then, the solution was heated at 200° C. for 24 hours.
다음으로, 이 용액을 Tip sonicator를 이용하여, 20kHz의 주파수로 30분간 초음파 분산하고, 다시 bath sonicator를 이용하여, 68kHz의 주파수로 3시간 초음파 분산하였다.Next, this solution was ultrasonically dispersed for 30 minutes at a frequency of 20kHz using a tip sonicator, and then ultrasonically dispersed for 3 hours at a frequency of 68kHz using a bath sonicator.
그리고 이 분산용액을 원심분리기를 이용하여 2500rpm에서 30분간 원심분리하고, 이 용액의 상등액을 80% 수득하였다. And this dispersion solution was centrifuged at 2500 rpm for 30 minutes using a centrifuge, and 80% of the supernatant of this solution was obtained.
(비교예 1)(Comparative Example 1)
h-BN power(평균입경 10㎛)와 용매인 ethyl acetate을 반응기에 투입하고, 이를 1일간 200rpm의 속도로 교반, 혼합하였다. 이때, 그 농도는 0.66mg/ml였다. h-BN power (average particle diameter of 10 μm) and ethyl acetate as a solvent were put into a reactor, and they were stirred and mixed at a speed of 200 rpm for one day. At this time, the concentration was 0.66mg/ml.
다음으로, 이 용액을 Tip sonicator를 이용하여, 20kHz의 주파수로 30분간 초음파 분산하고, 다시 bath sonicator를 이용하여, 68kHz의 주파수로 3시간 초음파 분산하였다.Next, this solution was ultrasonically dispersed for 30 minutes at a frequency of 20kHz using a tip sonicator, and then ultrasonically dispersed for 3 hours at a frequency of 68kHz using a bath sonicator.
그리고 이 분산용액을 원심분리기를 이용하여 2500rpm에서 30분간 원심분리하고, 이 용액의 상등액을 80% 수득하였다. And this dispersion solution was centrifuged at 2500 rpm for 30 minutes using a centrifuge, and 80% of the supernatant of this solution was obtained.
(시험예 1)(Test Example 1)
실시예 1, 2의 분산용액을 분산직후, 그리고 원심분리 후 광학사진을 촬영하여 그 결과를 도 2에 나타내었다.Optical photographs were taken immediately after the dispersion solutions of Examples 1 and 2 were dispersed and after centrifugation, and the results are shown in FIG. 2 .
도 2에서와 같이, 본 발명의 실시예 1은 비교예 1에 비하여 매우 안정적인 분산상을 나타냄을 확인하였다.As shown in FIG. 2, it was confirmed that Example 1 of the present invention exhibited a very stable dispersed phase compared to Comparative Example 1.
(시험예 2)(Test Example 2)
실시예 1의 용매열 공정 전후의 h-BN power를 XRD 분석하고, 그 결과를 도 3에 나타내었다.XRD analysis was performed on the h-BN power before and after the solvothermal process of Example 1, and the results are shown in FIG. 3 .
도 3에서와 같이, 용매열 공정 후 h-BN power의 면간거리가 다소 감소한 것을 확인하였다. 즉, 용매열 공정으로 인해 용매가 h-BN의 층간에 intercalation됨으로써, 층간 결합력이 약화되었음을 확인하였다.As shown in FIG. 3, it was confirmed that the interplanar distance of h-BN power slightly decreased after the solvothermal process. That is, it was confirmed that the intercalation of the solvent between the layers of h-BN due to the solvothermal process weakened the bonding force between the layers.
(시험예 3)(Test Example 3)
실시예 1과 비교예 1의 분산 결과를 비교하였다. 상기 분산 결과는 주사전자현미경(SEM) 및 원자간력현미경(AFM) 분석을 통해 실시하였다. 그리고 그 결과는 도 4에 나타내었다.The dispersion results of Example 1 and Comparative Example 1 were compared. The dispersion results were carried out through scanning electron microscopy (SEM) and atomic force microscopy (AFM) analysis. And the results are shown in Figure 4.
도 4와 같이, 실시예 1의 분산용액이 비교예 1의 분산용액에 비하여 h-BNNS의 면방향 크기(lateral size)가 월등히 크고, 두께가 얇음을 확인할 수 있었다. As shown in FIG. 4, it was confirmed that the dispersion solution of Example 1 had a much larger lateral size and thinner thickness of h-BNNS than the dispersion solution of Comparative Example 1.
더욱 구체적으로, 비교예 1의 h-BNNS는 면방향 크기가 0.47㎛, 0.38㎛, 0.46㎛, 0.40㎛, 0.65㎛ 정도이고, 그 두께는 최소 20.1nm 이상이나, 실시예 1의 h-BNNS는 면방향 크기가 1.108㎛, 1.015㎛ 수준으로 1㎛ 이상이고, 두께는 2.86nm 2.91nm 수준으로 5nm 이하임을 확인할 수 있었다.More specifically, the h-BNNS of Comparative Example 1 has a plane direction size of about 0.47 μm, 0.38 μm, 0.46 μm, 0.40 μm, and 0.65 μm, and the thickness is at least 20.1 nm or more, but the h-BNNS of Example 1 has It was confirmed that the size in the plane direction was 1 μm or more at the level of 1.108 μm and 1.015 μm, and the thickness was 5 nm or less at the level of 2.86 nm and 2.91 nm.
따라서, 본 발명에 의하면 대면적의 h-BNNS 분산용액을 제조할 수 있음을 알 수 있었다.Accordingly, it was found that a large-area h-BNNS dispersion solution could be prepared according to the present invention.
(시험예 4)(Test Example 4)
실시예 1과 비교예 1의 분산용액의 분산도를 측정하였다. 상기 분산도는 UV-Vis 광학 측정기로부터 얻어진 흡광도를 분석하여 측정하였으며, 그 결과는 도 5에 나타내었다.The degree of dispersion of the dispersion solutions of Example 1 and Comparative Example 1 was measured. The dispersion was measured by analyzing the absorbance obtained from a UV-Vis optical measuring instrument, and the results are shown in FIG. 5 .
도 5와 같이, 실시예 1은 비교예 1에 비하여 그 분산도가 우수함을 확인할 수 있었다.As shown in FIG. 5, it was confirmed that Example 1 had excellent dispersion compared to Comparative Example 1.
상기한 시험예들에서 확인할 수 있는 바와 같이, 본 발명에 의하면 분산 안정도가 우수하고, 대면적을 갖는 h-BNNS 분산용액의 제조가 가능함을 확인할 수 있었다. As can be seen from the above test examples, according to the present invention, it was confirmed that it is possible to prepare an h-BNNS dispersion solution having excellent dispersion stability and having a large area.
이상으로 본 발명의 특정한 부분을 상세히 기술하였는바, 당 업계의 통상의 지식을 가진 자에게 있어서 이러한 구체적인 기술은 단지 바람직한 구현예일 뿐이며, 이에 본 발명의 범위가 제한되는 것이 아닌 점은 명백하다. 따라서, 본 발명의 실질적인 범위는 첨부된 청구항과 그의 등가물에 의하여 정의된다고 할 것이다.Having described specific parts of the present invention in detail above, it is clear that these specific techniques are only preferred embodiments for those skilled in the art, and the scope of the present invention is not limited thereto. Accordingly, the substantial scope of the present invention will be defined by the appended claims and equivalents thereof.
Claims (6)
상기 전처리된 용액에 외부 에너지를 공급하여 육방정계 질화붕소를 박리함으로써, 대면적 육방정계 질화붕소 나노시트(h-BNNS) 분산용액을 제조하는 분산 단계를 포함하는 것을 특징으로 하는 용매열 방법을 이용한 대면적 육방정계 질화붕소 나노시트 분산용액의 제조방법.
A pretreatment step of mixing hexagonal boron nitride (h-BN) and a solvent and performing heat treatment to intercalate the solvent between layers of h-BN;
A dispersion step of preparing a large-area hexagonal boron nitride nanosheet (h-BNNS) dispersion solution by exfoliating the hexagonal boron nitride by supplying external energy to the pretreated solution using a solvothermal method Method for preparing a large-area hexagonal boron nitride nanosheet dispersion solution.
상기 용매는 에틸 아세테이트(ethyl acetate), 메틸 아세테이트(methyl acetate), 메틸에틸케톤(methyl ethyl ketone), 메틸프로틸케톤(methyl propyl ketone) 중 1종 이상인 것을 특징으로 하는 용매열 방법을 이용한 대면적 육방정계 질화붕소 나노시트 분산용액의 제조방법.
According to claim 1,
The solvent is at least one of ethyl acetate, methyl acetate, methyl ethyl ketone, and methyl propyl ketone. Manufacturing method of hexagonal boron nitride nanosheet dispersion solution.
상기 가열 처리는,
180∼220℃에서 10~48시간 수행하는 것을 특징으로 하는 용매열 방법을 이용한 대면적 육방정계 질화붕소 나노시트 분산용액의 제조방법.
According to claim 1,
The heat treatment,
Method for producing a large-area hexagonal boron nitride nanosheet dispersion solution using a solvothermal method, characterized in that it is performed at 180 to 220 ° C. for 10 to 48 hours.
상기 분산용액 내 육방정계 질화붕소 나노시트는,
평균 면방향 크기(lateral size)가 1㎛ 이상이고, 두께가 5nm 이하인 것을 특징으로 하는 용매열 방법을 이용한 대면적 육방정계 질화붕소 나노시트 분산용액의 제조방법.
According to claim 1,
The hexagonal boron nitride nanosheet in the dispersion solution,
A method for producing a large-area hexagonal boron nitride nanosheet dispersion solution using a solvothermal method, characterized in that the average lateral size is 1 μm or more and the thickness is 5 nm or less.
상기 분산용액 내 육방정계 질화붕소 나노시트는,
1~3개의 층으로 구성됨을 특징으로 하는 용매열 방법을 이용한 대면적 육방정계 질화붕소 나노시트 분산용액의 제조방법.
According to claim 4,
The hexagonal boron nitride nanosheet in the dispersion solution,
Method for producing a large-area hexagonal boron nitride nanosheet dispersion solution using a solvothermal method, characterized in that it consists of 1 to 3 layers.
상기 외부 에너지는 초음파인 것을 특징으로 하는 용매열 방법을 이용한 대면적 육방정계 질화붕소 나노시트 분산용액의 제조방법.According to claim 1,
The external energy is a method for producing a large-area hexagonal boron nitride nanosheet dispersion solution using a solvothermal method, characterized in that ultrasonic waves.
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| KR101637220B1 (en) | 2014-10-20 | 2016-07-08 | 한국원자력연구원 | The method for manufacturing of boron nitride nanosheet and boron nitride nanosheet thereby |
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