• 반도체디스플레이기술학회지
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• 제6권1호
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• pp.27-30
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• 2007

The gigahertz oscillator behavior of double-walled boron-nitride nanotube (BNNT) was investigated by using classical molecular dynamics simulations. The BNNT oscillator characteristics were compared to carbon-nanotube (CNT) and hybrid-C@BNNT oscillators. The results show that the BNNT oscillators are higher than the van der Waals force of the CNT oscillator. Since the frictional effects of BNNT oscillators are higher than that of a CNT oscillator, the damping factors of BNNT and hybrid oscillators are higher than that of a CNT oscillator.

• Transactions on Electrical and Electronic Materials
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• 제5권6호
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• pp.227-232
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• 2004

We investigated a nonvolatile nanomemory element based on boron nitride nanopeapods using molecular dynamics simulations. The studied system was composed of two boron-nitride nanotubes filled Cu electrodes and fully ionized endo-fullerenes. The two boron-nitride nanotubes were placed face to face and the endo-fullerenes came and went between the two boron-nitride nanotubes under alternatively applied force fields. Since the endo-fullerenes encapsulated in the boron-nitride nanotubes hardly escape from the boron-nitride nanotubes, the studied system can be considered to be a nonvolatile memory device. The minimum potential energies of the memory element were found near the fullerenes attached copper electrodes and the activation energy barrier was $3{\cdot}579 eV$. Several switching processes were investigated for external force fields using molecular dynamics simulations. The bit flips were achieved from the external force field of above $3.579 eV/{\AA}$.

• Advances in nano research
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• 제5권1호
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• pp.1-12
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• 2017

In this paper, the critical buckling temperature of single-walled Boron Nitride nanotube (SWBNNT) is estimated using a new nonlocal first-order shear deformation beam theory. The present model is capable of capturing both small scale effect and transverse shear deformation effects of SWBNNT and is based on assumption that the inplane and transverse displacements consist of bending and shear components, in which the bending components do not contribute toward shear forces and, likewise, the shear components do not contribute toward bending moments. Results indicate the importance of the small scale effects in the thermal buckling analysis of Boron Nitride nanotube.

• Membrane and Water Treatment
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• 제9권1호
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• pp.63-68
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• 2018

Molecular dynamics simulations were used to study the removal of Cd(II) as a heavy metal from wastewater using armchair carbon nanotube, boron nitride nanotube and silicon carbide nanotubes under applied electric field. The system contains an aqueous solution of $CdCl_2$ as a heavy metal and a (7,7) nanotube as a nanostructured membrane, embedded in a silicon nitride membrane. An external electric field was applied to the considered system for the removal of $Cd^{2+}$ through nanotubes. The simulation results show that in the same conditions, considered armchair nanotubes were capable to remove $Cd^{2+}$ from wastewater with different ratios. Our results reveal that the removal of heavy metals ions through armchair carbon, boron nitride and silicon carbide nanotubes was attributed to the applied electric field. The selective removal phenomenon is explained with the calculation of potential of mean force. Therefore, the investigated systems can be recommended as a model for the water treatment.

• 한국정밀공학회지
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• 제21권6호
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• pp.22-27
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• 2004

특성에 대한 많은 연구가 진행되었고, 새로운 나노 소자로서의 가능성을 보여왔다. CNT의 전기적 성질은 직경과 chirality 의 함수로서 금속 혹은 반도체 성질을 주기적으로 가지며, 이론적 연구에 의하면 단일구역의 CNT 는 1/3 이 금속성, 나머지는 밴드갭이 수 ㎷ 로 아주 작고, 나노튜브의 직경에 반비례하는 반도체 성질을 나타낸다.(중략)

• 공업화학전망
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• 제20권4호
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• pp.21-33
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• 2017

질화붕소나노튜브(BNNT: Boron Nitride Nanotube)는 뛰어난 기계적 물성과 전기적 절연성, 높은 열전도도, 열적/화학적 안정성 및 열중성자 흡수 등의 물리화학적 특성으로 인해 다양한 과학기술 분야에서 응용될 수 있는 소재이다. BNNT의 응용성을 증진시키기 위해서 정제 및 표면개질을 통해 BNNT 합성 공정 중 포함되는 불순물의 제거와 용매와 기재에 대한 상용성을 개선해야 할 필요성이 있다. 이에 본 기고에서는 BNNT의 정제 및 표면처리 연구동향에 대해 소개하고자 한다.

• 진공이야기
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• 제3권3호
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• pp.19-23
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• 2016

BNNTs (Boron nitride nanotubes) is an analogue of CNTs (Carbon Nanotubes) in terms of lattice structure. In BNNTs, a boron atom forms sp2 hybridized bonding with three nitrogen atoms, and so does a nitrogen with three boron atoms in the honeycomb structure. Its innovative properties, such as high thermal conductivity, neutron shielding capability, superb oxidation resistance at $900^{\circ}C$, excellent chemical resistance, and superior mechanical properties are advantageous for a wide range of applications, especially for electric device packages, neutron shielding, protective coating materials, and functional composites. In this paper, boron nitride nanotube synthesis, properties and application are reviewed.

• Bulletin of the Korean Chemical Society
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• 제33권10호
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• pp.3285-3292
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• 2012

The interaction of thiazole drug with (6,0) zigzag single-walled boron nitride nanotube of finite length in gas and solvent phases was studied by means of density functional theory (DFT) calculations. In both phases, the binding energy is negative and presenting characterizes an exothermic process. Also, the binding energy in solvent phase is more than that the gas phase. Binding energy corresponding to adsorption of thiazole on the BNNT model in the gas and solvent phases was calculated to be -0.34 and -0.56 eV, and about 0.04 and 0.06 electrons is transferred from the thiazole to the nanotube in the phases. The significantly changes in binding energies and energy gap values by the thiazole adsorption, shows the high sensitivity of the electronic properties of BNNT towards the adsorption of the thiazole molecule. Frontier molecular orbital theory (FMO) and structural analyses show that the low energy level of LUMO, electron density, and length of the surrounding bonds of adsorbing atoms help to the thiazole adsorption on the nanotube. Decrease in global hardness, energy gap and ionization potential is due to the adsorption of the thiazole, and consequently, in the both phases, stability of the thiazole-attached (6,0) BNNT model is decreased and its reactivity increased. Presence of polar solvent increases the electron donor of the thiazole and the electrophilicity of the complex. This study may provide new insight to the development of functionalized boron nitride nanotubes as drug delivery systems for virtual applications.

• 한국분말재료학회지
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• 제25권2호
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• pp.120-125
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• 2018

Boron nitride nanotubes (BNNTs) are receiving great attention because of their unusual material properties, such as high thermal conductivity, mechanical strength, and electrical resistance. However, high-throughput and high-efficiency synthesis of BNNTs has been hindered due to the high boiling point of boron (${\sim}4000^{\circ}C$) and weak interaction between boron and nitrogen. Although, hydrogen-catalyzed plasma synthesis has shown potential for scalable synthesis of BNNTs, the direct use of $H_2$ gas as a precursor material is not strongly recommended, as it is extremely flammable. In the present study, BNNTs have been synthesized using radio-frequency inductively coupled thermal plasma (RF-ITP) catalyzed by solid-state ammonium chloride ($NH_4Cl$), a safe catalyst materials for BNNT synthesis. Similar to BNNTs synthesized from h-BN (hexagonal boron nitride) + $H_2$, successful fabrication of BNNTs synthesized from $h-BN+NH_4Cl$ is confirmed by their sheet-like properties, FE-SEM images, and XRD analysis. In addition, improved dispersion properties in aqueous solution are found in BNNTs synthesized from $h-BN+NH_4Cl$.

• Composites Research
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• 제30권4호
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• pp.247-253
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• 2017

본 연구에서는 분자동역학 전산모사와 이중 입자 모델을 이용하여 질화붕소 나노튜브-폴리메틸메타크릴레이트 나노복합재의 기계적 물성과 계면특성을 규명하였다. 단일 벽 나노튜브가 고분자 기지에 함침된 가로등방성 나노복합재 단위 셀 구조를 모델링한 후, 각 방향으로의 일축인장 및 전단 전산모사를 통해 나노복합재의 강성행렬을 예측하였다. 또한 강성행렬의 방향 평균을 취해 나노튜브가 기지 내에 랜덤 분포하는 경우의 등방성 탄성계수를 도출하였다. 분자동역학 해석 결과를 계면의 완전 결합을 가정한 이중 입자 모델 예측해와 비교한 결과, 질화붕소 나노튜브와 고분자 기지간의 계면이 불완전한 것으로 확인되었다. 나노튜브 주위에 형성되는 흡착계면의 물성을 예측하기 위해 2단계 영역 분할 기법을 도입하였고 계면의 불완전 결합을 선형 스프링으로 묘사하였다. 그 결과 다양한 스프링 컴플라이언스 값에 따른 흡착계면의 물성을 역 해석을 통해 확인할 수 있었다.