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A New Target for Synthesis: Theoretical Prediction for the Reaction between boron nitride nanotube and Dichlorocarbene

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Chinese Journal of Structural Chemistry 2009年第1期28卷 113-119页

作者：李瑞芳尚贞锋王贵昌许秀芳 Chemistry Department of Nankai University

Understanding the chemistry of BNNT is a crucial step toward their ultimate practical use. A comparative study of Reactions A （ASWCNT （5,5） and CCl2） and B （ASWBNNT （5,5） and CCl2） have been performed by using ONIOM （B3LYP/6-31G＊： AM1） method in Gaussian03 program package. The results show that （1） the two reactions are both exothermic; （2） the mechanism of Reaction B is a two-step mechanism; （3） the difference in energy barriers suggests that the reaction of CCl2 with BNNT is easier than with CNT; （4） in reaction B, CCl2 prefers to attack the boron atom of BNNT first.

关键词： carbon nanotube boron nitride nanotube dichlorocarbene reaction mechanism theoretical study

Electrostabilized homogeneous dispersion of boron nitride nanotubes in wide-range of solvents achieved by surface polarity modulation through pyridine attachment

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Nano Research 2020年第2期13卷 344-352页

作者： Mi Se Chang Min-Sun Jang Sangsun Yang Jihun Yu Taehoon Kim Sedong Kim Hyomin Jeong Chong Rae Park Jae Won Jeong Powder/Ceramic Research Division Korea Institute of Materials Science797 Changwondae-roSeongsan.guChangwon 51508Republic of Korea Research Institute of Advanced Materials and Department of Materials Science and Engineering Seoul National University Seoul 08826Republic of Korea Composites Research Division Korea Institute of Materials Science797 Changwondae-roSeongsan-guChangwon 51508Republic of Korea Dept.of Energy and Mech.Eng Gyeongsang National UniversityCheondaegukchi-Gil 38Tongyeong 53064Republic of Korea

boron nitride nanotubes(BNNTs)show exceptional physical properties including high mechanical strength and thermal conductivity;however,their applications have been restricted due to limited dispersibility in processing ***,a novel BNNT dispersion method with exceptional dispersibility in a wide range of solvents has been demonstrated by surtace polarity modulation through short-molecule pyridine *** atoms in pyridine are selectively bonded to electron-deficient boron atoms of the BNNT surface through Lewis acid-base reaction,which changes the surface polarity of BNNTs from neutral to ***-dispersing pyridine-attached BNNTs(Py-BNNTs)create a thick and stable electronic double layer(EDL),resulting in uniform dispersion of BNNTs in solvents with an exceptional solubility parameter range of 18.5-48 MPa^1/*** uniform dispersion of BNNTs is maintained even after the mixing with diverse ***,composites incorporating uniformly-distributed BNNTs have been realized,and extraordinary property enhancements have been *** thermal conductivity of 20 wt.%Py-BNNT/epoxy composite has been significantly improved by 69.6%and the tensile strength of 2 wt.%Py-BNNT/PVA has been dramatically improved by 75.3%.Our work demonstrates a simple and facile route to dispersing BNNTs in diverse solvents,consequently leading to selective utlization of BNNT dispersed solvents in various application fields.

关键词： boron nitride nanotube one-dimensional nanomaterials surface polarity modulation electrostabilization boron nitride nanotube composite

Mechanosynthesis of boron nitride nanotubes

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Chinese Journal of Chemical Engineering 2006年第3X期14卷 389-393页

作者：籍凤秋曹传宝徐红杨子光 Department of Traffic Engineering Shijiazhuang Railway Institute of Technology Shijiazhuang 050043 China Research Center of Material Science Beijing Institute of Technology Beijing 100081 China Department of Computer Engineering Shijiazhuang Railway Institute of Technology Shijiazhuang 050043 China

boron nitride nanotubes （BN-NTs） with pure hexagonal BN phase have been synthesized by heating ball-milled boron powders in flowing ammonia gas at a temperature of 1200℃. The as-synthesized products were characterized by X-ray powder diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, and electron energy loss spectroscopy （EELS）. The diameters of nanotubes are in the rage of 40-120nm and the lengths are more than 10μm. EELS result identifies that the ratio of boron and nitrogen is almost 1：1 The growth temperature is a crucial growth parameter in controlling the structure and crystalline of BN-NTs. The nanotubes grown at 1100℃ possesses of a bamboo-like structure, while as the temperature increased to 1200℃, most of the nanotubes exhibited a cylindrical structure. In addition, changing the heating time can control the size of the nanotubes. The gas atmosphere has influence on the yield of BN-NTs during heating process. When heating atmosphere was replaced by nitrogen, the yield of nanotubes was remarkably decreased.

关键词： boron nitride nanotube mechanosynthesis cylindrical morphology bamboo-like structure

The Buckling Behavior of boron nitride nanotubes under Bending： An Atomistic Study

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Journal of Environmental Science and Engineering(A) 2017年第6期6卷 308-312页

作者： Van-Trang Nguyen Department of Mechanical Design and Manufacture Faculty of Mechanical Engineering Thai Nguyen University of Technology Thai Nguyen City 250000 Vietnam

In this paper, the buckling behavior of zigzag BN （boron nitride） nanotubes under bending is studied through molecular dynamics finite element method with Tersoff potential. The tube with namely （15, 0） BN zigzag tube is investigated. The critical bending buckling angle, moment and curvature are studied and examined with respect to the tube length-diameter ratios from 5 to 30. Effects of a SW （Stone-Wales） defect in the middle tube on the bending behavior are also discussed. The results show that the tube length affects significantly the bending behavior of these tubes. All tubes exhibit brittle fracture under bending. The buckling takes place at the middle in the compressive side of these tubes. These results are important information on the buckling behaviors of pristine and Stone-Wales BN nanotubes, which will be useful for their future applications.

关键词： Atomistic simulation bending boron nitride nanotube buckling.

A topologically substituted boron nitride hybrid aerogel for highly selective CO2 uptake

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Nano Research 2018年第12期11卷 6325-6335页

作者： R.Govindan Kutty Sivaramapanicker Sreejith Xianghua Kong Haiyong He Hong Wang Junhao Lin Kazu Suenaga Chwee Teck Lim Yanli Zhao Wei Ji Zheng Liu Center for Programmable Materials School of Materials Sdence and EngineeringNanyang Technological UniversitySO Nanyang Avenue639798Singapore School of Materials Science and EngineeringNanyang Technological UniversitySingapore 639798Singapore Center for Advanced 2D Materials and Graphene Research Center National University of Singapore6Science Drive 2Singapore117546Singapore Biomedical Institute for Global Health Research and Technology National University of Singapore14Medical DriveSingapore 117599Singapore Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-Nano Devices Renmin University of ChinaBeijing 100872China National Institute of Advanced Industrial Science and Technology (AIST) AIST Central 5Tsukuba305-8565-Japan Division of Chemistry and Biological Chemistry School of Physical and Mathematical SciencesNanyang Technological University21-Nanyang LinkSingapore 637371Singapore Department of Biomedical Engineering National University of SingaporeSingapore 117543Singapore

A topologically mediated synthesis of porous boron nitride aerogel has been experimentally and theoretically investigated for carbon dioxide (CO2) uptake. Replacement of the carbon atoms in a precursor aerogel of graphene oxide and carbon nanotubes was achieved using an elemental substitution reaction, to obtain a boron and nitrogen framework. The newly prepared BN aerogel possessed a specific surface area of 716.56 m2/g and exhibited an unprecedented twentyfold increase in CO2 uptake over N2, adsorbing 100 cc/g at 273 K and 80 cc/g in ambient conditions, as verified by adsorption isotherms via the multipoint Brunauer-Emmett-Teller (BET) method. Density functional theory calculations were performed to give hints on the mechanism of such high selectivity of CO2 over N2 adsorption in BN aerogel, which may be due to the interaction between the intrinsic polar nature of B–N bonds and the high quadrupole moment of CO2 over N2.

关键词： boron nitride boron nitride nanotube aerogel quadrupole moment selective CO 2 adsorption

Length dependence of linear and nonlinear optical properties of finite-length BN（5,0） nanotube

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Chinese Physics B 2006年第7期15卷 1563-1569页

作者：蓝尤钊吴东升黄淑萍沈娟李飞飞程文旦 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterThe Graduate School of The Chinese Academy of Sciences Fuzhou 350002 China

In this paper, we investigate the length dependence of linear and nonlinear optical properties of finite-length BN nanotubes. The recently predicted smallest BN（5,0） nanotube with configuration stabilization is selected as an example. The energy gap and optical gap show the obvious length dependence with the increase of nanotube length. When the length reaches about 24 /~, the energy gap will saturate at about 3.2 eV, which agrees well with the corrected quasi- particle energy gap. The third-order polarizabilities increase with the increase of tube length. Two-photon allowed excited states have significant contributions to the third-order polarizabilities of BN（5,0） nanotube.

关键词： boron nitride nanotube length-dependence optical properties