Novel highly symmetrical trivalent graphs which lead to negative curvature carbon and boron nitride chemical structures

: Emerging nanotechnology in the early 1990s introduced nanoscaled and advanced materials such as Carbon Nanotubes (CNT) with specific chemical structures and exceptionally unique properties. Among various nanostructures, particularly nanotubes have shown their specific values due to their inherent characteristics. With time, new vistas were opened for developing other nanotube-based materials due to their remarked mechanical strength and versatile applications. In recent decades, BNNTs with promising applicability have been synthesized via several methods. This review highlights the synthetic strategies of Boron Nitride Nanotubes (BNNTs) with their potential applications in various applied sectors, including energy, electronics, and biomedical applications.

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Preparation and Characterization of Polyaniline/Hexagonal Boron Nitride Composites

High Temperature Materials and Processes ◽

10.1515/htmp-2013-0003 ◽

2013 ◽

Vol 32 (6) ◽

pp. 557-561 ◽

Cited By ~ 2

Author(s):

Emrah Çakmakçı ◽

Seyfullah Madakbaş

Keyword(s):

Boron Nitride ◽

Hexagonal Boron Nitride ◽

Conductive Polymer ◽

Ftir Analysis ◽

Dielectric Measurements ◽

Glass Transition Temperatures ◽

Chemical Structures ◽

Dsc Measurements ◽

Tga And Dsc

AbstractPolyaniline (PANI) is one of the most studied conductive polymer with several unique properties and good conductivity. In this study it was aimed to prepare Polyaniline (PANI)/Hexagonal boron nitride (h-BN) composites. Chemical structures of the composites were characterized by FTIR analysis. Thermal properties of these novel composites were analyzed by TGA and DSC measurements. Glass transition temperatures and char yields of the composites increased with increasing h-BN percentage. FTIR, XRD and UV measurements indicated that the boron atoms in h-BN particles interact with the unpaired electrons in nitrogen atoms of PANI. Dielectric measurements revealed dipolar polarization behavior of the composites.

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Negative Curvature Surfaces in Chemical Structures

Journal of Chemical Information and Computer Sciences ◽

10.1021/ci970063+ ◽

1998 ◽

Vol 38 (2) ◽

pp. 180-188 ◽

Cited By ~ 7

Author(s):

R. B. King

Keyword(s):

Negative Curvature ◽

Chemical Structures

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BN-schwarzite: novel boron nitride spongy crystals

Physical Chemistry Chemical Physics ◽

10.1039/c6cp06424h ◽

2017 ◽

Vol 19 (2) ◽

pp. 1167-1173 ◽

Cited By ~ 8

Author(s):

Pengfei Gao ◽

Xi Chen ◽

Lei Guo ◽

Zhifeng Wu ◽

Erhu Zhang ◽

...

Keyword(s):

Energy Storage ◽

Boron Nitride ◽

Specific Surface ◽

First Principles ◽

Environmental Remediation ◽

Negative Curvature ◽

Great Promise ◽

Large Specific Surface Area ◽

First Time ◽

Molecular Sieving

Novel 3-D BN crystals with a negative curvature, intrinsic porosity and a large specific surface area are proposed for the first time by first-principles study, suggesting that the BN crystals hold great promise in the fields of energy storage, molecular sieving, and environmental remediation.

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Development of Crystallinity in Turbostratic Boron Nitride Derived from Polymeric Precursors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100089081 ◽

1991 ◽

Vol 49 ◽

pp. 954-955

Author(s):

X. Qiu ◽

A. K. Datye ◽

T. T. Borek ◽

R. T. Paine

Keyword(s):

Thermal Treatment ◽

Boron Nitride ◽

Diffraction Pattern ◽

Polymeric Precursors ◽

Polymer Precursors ◽

Diffuse Ring

Boron nitride derived from polymer precursors is of great interest for applications such as fibers, coatings and novel forms such as aerogels. The BN is prepared by the polymerization of functionalized borazine and thermal treatment in nitrogen at 1200°C. The BN powders obtained by this route are invariably trubostratic wherein the sheets of hexagonal BN are randomly oriented to yield the so-called turbostratic modification. Fib 1a and 1b show images of BN powder with the corresponding diffraction pattern in fig. 1c. The (0002) reflection from BN is seen as a diffuse ring with occational spots that come from crystals of BN such as those shown in fig. 1b. The (0002) lattice fringes of BN seen in these powders are the most characteristic indication of the crystallinity of the BN.

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Structural relationships in the synthesis of cubic boron nitride thin films by ion-assisted deposition

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017092x ◽

1994 ◽

Vol 52 ◽

pp. 638-639

Author(s):

D. L. Medlin ◽

T. A. Friedmann ◽

P. B. Mirkarimi ◽

M. J. Mills ◽

K. F. McCarty

Keyword(s):

Boron Nitride ◽

Ion Irradiation ◽

Cubic Boron Nitride ◽

Film Stress ◽

Bonded Phases ◽

Structural Relationships ◽

Precursor Material ◽

Pressure Synthesis ◽

Microstructure Of The Material

The allotropes of boron nitride include two sp2-bonded phases with hexagonal and rhombohedral structures (hBN and rBN) and two sp3-bonded phases with cubic (zincblende) and hexagonal (wurtzitic) structures (cBN and wBN) (Fig. 1). Although cBN is synthesized in bulk form by conversion of hBN at high temperatures and pressures, low-pressure synthesis of cBN as a thin film is more difficult and succeeds only when the growing film is simultaneously irradiated with a high flux of ions. Only sp2-bonded material, which generally has a disordered, turbostratic microstructure (tBN), will form in the absence of ion-irradiation. The mechanistic role of the irradiation is not well understood, but recent work suggests that ion-induced compressive film stress may induce the transformation to cBN.Typically, BN films are deposited at temperatures less than 1000°C, a regime for which the structure of the sp2-bonded precursor material dictates the phase and microstructure of the material that forms from conventional (bulk) high pressure treatment.

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Chemical structure of diamond-like carbon thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017668x ◽

1990 ◽

Vol 48 (4) ◽

pp. 710-711

Author(s):

N.-H. Cho ◽

K.M. Krishnan ◽

D.B. Bogy

Keyword(s):

Electrical Resistivity ◽

Chemical Structure ◽

Diamond Like Carbon ◽

Chemical Structures ◽

Sputtering Power ◽

Data Aquisition ◽

Equilibrium Phases ◽

Electron Energy Loss ◽

Power Densities ◽

Preparation Techniques

Diamond-like carbon (DLC) films have attracted much attention due to their useful properties and applications. These properties are quite variable depending on film preparation techniques and conditions, DLC is a metastable state formed from highly non-equilibrium phases during the condensation of ionized particles. The nature of the films is therefore strongly dependent on their particular chemical structures. In this study, electron energy loss spectroscopy (EELS) was used to investigate how the chemical bonding configurations of DLC films vary as a function of sputtering power densities. The electrical resistivity of the films was determined, and related to their chemical structure.DLC films with a thickness of about 300Å were prepared at 0.1, 1.1, 2.1, and 10.0 watts/cm2, respectively, on NaCl substrates by d.c. magnetron sputtering. EEL spectra were obtained from diamond, graphite, and the films using a JEOL 200 CX electron microscope operating at 200 kV. A Gatan parallel EEL spectrometer and a Kevex data aquisition system were used to analyze the energy distribution of transmitted electrons. The electrical resistivity of the films was measured by the four point probe method.

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Molecular insights on the dynamic stability of peptide nucleic acid functionalized carbon and boron nitride nanotubes

Physical Chemistry Chemical Physics ◽

10.1039/d0cp05759b ◽

2021 ◽

Vol 23 (1) ◽

pp. 219-228

Author(s):

Nabanita Saikia ◽

Mohamed Taha ◽

Ravindra Pandey

Keyword(s):

Nucleic Acid ◽

Boron Nitride ◽

Nucleic Acids ◽

Dynamic Stability ◽

Peptide Nucleic Acid ◽

Rational Design ◽

Peptide Nucleic Acids ◽

Boron Nitride Nanotubes ◽

Molecular Hybrids ◽

Single Wall Nanotubes

The rational design of self-assembled nanobio-molecular hybrids of peptide nucleic acids with single-wall nanotubes rely on understanding how biomolecules recognize and mediate intermolecular interactions with the nanomaterial's surface.

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