Gram Scale and Room Temperature Functionalization of Boron Nitride Nanosheets for Water Treatment

Shirin Daneshnia,MOHSEN ADELI,Yaghoub Mansourpanah 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.8

Two-dimensional hexagonal boron nitride is a fascinating nanomaterial with a broad range of potential applications. However, further development of this nanomaterial is hampered because of its poor functionality and low processability. One of the efficient strategies for improving the processability of two-dimensional hexagonal boron nitride is the covalent functionalization of this nanomaterial. In this study, we report on a straightforward approach for functionalization of two-dimensional hexagonal boron nitride by lithium cyclopentadienyl and its application for water treatment. Cyclopentadienyl-functionalized boron nitride was characterized by different spectroscopy and microscopy methods as well as thermal and BET analysis. The synthesized nanomaterial was able to efficiently remove methylene blue from water in a short time. Adsorption capacity of this nanomaterial was as high as 476.3 mg/g, which was superior to the non-functionalized boron nitride. Our results showed that cyclopentadienyl-functionalized boron nitride is a promising candidate for the removal of cationic pollutants from water.

Molecular Dynamics Simulations of Nanomemory Element Based on Boron Nitride Nanotube-to-peapod Transition

황호정,Jeong Won Kang,Ki Ryang Byun 한국전기전자재료학회 2004 Transactions on Electrical and Electronic Material Vol.5 No.6

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 3.579 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 3.0 eV/ Å.

Molecular Dynamics Simulations of Nanomemory Element Based on Boron Nitride Nanotube-to-peapod Transition

Hwang Ho Jung,Kang Jeong Won,Byun Ki Ryang The Korean Institute of Electrical and Electronic 2004 Transactions on Electrical and Electronic Material Vol.5 No.6

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 $3.579 eV/{\AA}$.

밀도범함수이론을 이용한 결함을 가지는 hexagonal boron nitride의 물성 예측 방법

임영빈 한국산학기술학회 2024 한국산학기술학회논문지 Vol.25 No.2

Advances in artificial intelligence (AI), particularly machine learning and deep learning, have sparked interest in using computer calculations to predict material properties in material sciences. Density functional theory was used to propose a method for predicting the electrical properties of hexagonal boron nitride (h-BN) in the presence of vacancy defects. Three types of defects in the h-BN monolayer (boron vacancy, nitrogen vacancy, and boron-nitrogen vacancy) were considered. The pristine h-BN monolayer had an electrical band gap of 4.6 eV, indicating its insulating properties. A monovacancy with boron or nitrogen defects introduced a new energy level within the band gap. In the case of divacancy by boron and nitrogen defects, two energy levels emerged (i.e., 1.3 eV and 1.8 eV from the conduction band, respectively) between the band gap, producing an environment conducive to electron excitation from the valence to the conduction band. As defects in the h-BN monolayer increased, the band gap filled gradually with new energy states. Consequently, the electrical properties shifted from insulator to conductor. This research contributes a methodology for predicting the material properties through computational calculations, providing insights into the evolving electrical behavior of h-BN with varying defect densities.

Nanodiamond-attached exfoliated boron nitride/epoxy nanocomposites for microelectronics

( Zhang Yinhang ),박수진 한국공업화학회 2018 한국공업화학회 연구논문 초록집 Vol.2018 No.0

This research focused on evaluating the thermal and physical properties of a composite reinforced with nanodiamonds and epitaxial boron nitride in an epoxy matrix. Nanodiamond-attached exfoliated hexagonal boron nitride nanoplates were fabricated using 4, 4′-methylene diphenyl diisocyanate as the coupling agent. The morphology and structure of boron nitride (BN), exfoliated hexagonal BN nanoplates (EBN), and nanodiamond-attached EBN nanoplates (NDEBN) were determined. Epoxy composites were fabricated by in-situ polymerization and reinforced with various concentrations of either EBN or NDEBN nanoplates. These composites exhibited high thermal stability and high thermal conductivity, attributed to the exceptional thermal stability and thermal conductivity inherent in nanodiamond materials. In addition, inserting nanodiamond particles between BN layers prevented the BN nanosheet from forming agglomerates. We also found that nanodiamond particles improved dynamic mechanical properties.

Effect of Silicon Nitride Whisker Content on the Flexural Strength of Silicon Nitride-Boron Nitride-Silicon Carbide Multi-Layer Composites

Park, Dong-Soo,Cho, Byung-Wook The Korean Ceramic Society 2003 한국세라믹학회지 Vol.40 No.9

Multi-layer ceramic composites were prepared by tape casting followed by hot pressing using silicon nitride layer with silicon nitride whiskers, silicon nitride layer with silicon carbide particles and boron nitride-alumina layer. The whiskers were aligned during the casting. As the whisker content of the silicon nitride layer was increased up to 10 wt%, the flexural strength of the multi-layer composite was increased. However, further increase of the whisker content in the layer resulted in a rapid decrease of the strength of the composite. The results suggest that the strength of multi-layer ceramic composite showing non-catastrophic failure behavior can be significantly improved by incorporating the aligned whiskers in the layers.

$BCl3-NH3-Ar$계의 플라즈마화학증착공정을 이용한 질화붕소막의 합성

박범수,백영준,은광용 한국세라믹학회 1997 한국세라믹학회지 Vol.34 No.3

100-500KHz범위의 주파수전원을 인가하여 발생한 플라즈마를 이용하여 질화붕소(boron nitride)막의 합성시 육방정상(hexagonal phase)과 입방정상(cubic phase)의 생성거동을 관찰하였다. BCl3와 NH3를 붕소와 질소의 공급기체로 선택하였고 Ar과 수소를 carrier기체로 사용하였다. 합성변수로는 플라즈마전원의 전압, 기판의 bias, 합성압력, 기체의 조성, 기판의 온도이었는데, 합성된 박막은 FT-IR결과로부터 육방정과 입방정의 혼합상으로 나타났고, 각 상의 분률은 변수의 크기에 의존하였다. TEM분석결과 육방정으로만 구성된 박막은 비정질상으로 이루어졌으며, 입방정과 육방정의 혼합상의 경우는 비정질기지상에 수십 nanometer크기의 입방정입자가 분산된 구조를 하고 있었다. The effect of process parameter of plasma assisted chemical vapor deposition (PACVD) on the variation of the ratio between cubic boron nitride (c-BN) and hexagonal boron nitride (h-BN) in the film was in-vestigated. The plasma was generated by electric power with the frequency between 100 and 500 KHz. BCl3 and NH3 were used as a boron and nitrogen source respectively and Ar and hydrogen were added as a car-rier gas. Films were composed of h-BN and c-BN and its ratio varied with the magnitude of process parameters, voltage of the electric power, substrate bias voltage, reaction pressure, gas composition, sub-strate temperature. TEM observation showed that h-BN phase was amorphous while crystalline c-BN par-ticle was imbedded in h-BN matrix in the case of c-BN and h-BN mixed film.

Boron Nitride를 함유한 열경화성 액정 에폭시의 열분해 거동

황보세진,조승현,Hwangbo, Sejin,Cho, Seung Hyun 한국섬유공학회 2018 한국섬유공학회지 Vol.55 No.1

A liquid crystalline thermosetting-epoxy-based composite was fabricated using diglycidyl ether of 4,4'-biphenol, boron nitride as the filler, and sulfanilamide as the curing agent. To investigate the thermal behavior, thermogravimetric analysis was performed, and temperature differences of the sample were recorded when using 1.0-7.0 wt.% boron nitride. The activation energy for thermal decomposition was calculated using the Kissinger method and Flynn-wall method. The results showed that the activation energy was proportional to the amount of added filler.

Hexagonal Boron Nitride의 합성에 있어서 MgB₆ 첨가의 효과

이대진,지미정,최병현,이미재,조남희,차미선,Lee, Dae-Jin,Jee, Mi-Jung,Choi, Byung-Hyun,Lee, Mi-Jai,Cho, Nam-Hee,Cha, Mi-Sun 한국세라믹학회 2009 한국세라믹학회지 Vol.46 No.1

The h-BN powder was synthesized by amorphous $B_2O_3$ and activated carbon at $1550^{\circ}C$ in nitrogen atmosphere, whose properties were examined according to $MgB_6$ addition. Amount of $MgB_6$ addition was varied in the range of $0{\sim}$10\;wt% of the initial mixture. It was observed that $MgB_6$ addition led to an increase in the amount and the grain size of h-BN and decrease in the amount of $B_4C$ forming. When $MgB_6$ added 5 wt%, the amount and crystallinity of h-BN increased as the holding time at the synthesis temperature was prolonged. It was also confirmed that the regularity of three-dimensional ordering of h-BN increases.

Light metal hydrides - Potential hydrogen storage materials

Hayley Woolf,Ian Brown,Mark Bowden 한국물리학회 2008 Current Applied Physics Vol.8 No.3,4

Light metal nitride phases Li3BN2 and Mg 3BN3 have been synthesised as potential hydrogen storage materials. The formation pro-cesses using boron nitride and amorphous boron have been compared, showing that boron extracts nitrogen from the Li3N and Mg 3N2reactant phases and not from the nitrogen gas. This rate limiting solid state reaction is the rst in a three step reaction sequence to formthese ternary nitrides. The sensitivity of the reactions to low levels of impurity oxygen in the ow gas caused us to develop a closed reac-tion system methodology using nickel foil capsules.