Continuum model for low-frequency phonons of boron nitride nanotubes

Abstract We explored the mixing effect of 10B isotopes and boron (B) or nitrogen (N) vacancies on the atomic vibrational properties of (10, 0) single-wall boron nitride nanotubes (BNNT). The forced oscillation technique was employed to evaluate the phonon modes for the entire range (0-100%) of 10B isotopes and atomic vacancy densities ranging from 0 to 30%. With increasing isotope densities, we noticed a blue-shift of the Raman active A1 phonon peak, whereas an increased density of mixed or independent B and N vacancies resulted in the emergence of a new low-frequency peak and the annihilation of the A1 peak in the phonon density-of-states. High-energy optical phonons were localized as a result of both 10B isotopes and the presence of mixing defects. We generated typical mode patterns for different defects to show the phonon localization processes due to the defects. We found an asymmetrical nature of the localization length with increasing 10B isotope content, which corresponds well with the isotope inherited localization length of carbon nanotubes and mono-layer graphene. The localization length falls abruptly with the increase in concentration of both atomic vacancies (B or N) and mixing defects (10B isotope and vacancies). These findings are critical for understanding heat conduction and nanoscopic vibrational investigations like tip-enhanced Raman spectra in BNNT, which can map local phonon energies.

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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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Density Functional Theory Study of Antioxidant Adsorption onto Single- Wall Boron Nitride Nanotubes: Design of New Antioxidant Delivery Systems

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207322666190930113200 ◽

2019 ◽

Vol 22 (7) ◽

pp. 470-482

Author(s):

Samereh Ghazanfary ◽

Fatemeh Oroojalian ◽

Rezvan Yazdian-Robati ◽

Mehdi Dadmehr ◽

Amirhossein Sahebkar

Keyword(s):

Density Functional Theory ◽

Boron Nitride ◽

Vitamin C ◽

Electric Field ◽

External Electric Field ◽

Lipoic Acid ◽

Density Functional ◽

Cell Interaction ◽

Boron Nitride Nanotubes ◽

Functional Theory

Background: Boron Nitride Nanotubes (BNNTs) have recently emerged as an interesting field of study, because they could be used for the realization of developed, integrated and compact nanostructures to be formulated. BNNTs with similar surface morphology, alternating B and N atoms completely substitute for C atoms in a graphitic-like sheet with nearly no alterations in atomic spacing, with uniformity in dispersion in the solution, and readily applicable in biomedical applications with no obvious toxicity. Also demonstrating a good cell interaction and cell targeting. Aim and Objective: With a purpose of increasing the field of BNNT for drug delivery, a theoretical investigation of the interaction of Melatonin, Vitamin C, Glutathione and lipoic acid antioxidants using (9, 0) zigzag BNNTs is shown using density functional theory. Methods: The geometries corresponding to Melatonin, Vitamin C, Glutathione and lipoic acid and BNNT with different lengths were individually optimized with the DMOL3 program at the LDA/ DNP (fine) level of theory. Results: In the presence of external electric field Melatonin, Vitamin C, Glutathione and lipoic acid could be absorbed considerably on BNNT with lengths 22 and 29 Å, as the adsorption energy values in the presence of external electric field are considerably increased. Conclusion: The external electric field is an appropriate technique for adsorbing and storing antioxidants on BNNTs. Moreover, it is believed that applying the external electric field may be a proper method for controlling release rate of drugs.

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About the possibility of creating a high-performance sensor based on boron nitride nanotubes

10.1063/5.0033057 ◽

2020 ◽

Author(s):

N. P. Boroznina ◽

M. A. Vdovin ◽

I. V. Zaporotskova ◽

S. V. Boroznin ◽

P. A. Zaporotskov

Keyword(s):

Boron Nitride ◽

High Performance ◽

Boron Nitride Nanotubes

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Boron Nitride Nanotubes for Heat Dissipation in Polycaprolactone Composites

ACS Applied Nano Materials ◽

10.1021/acsanm.1c00365 ◽

2021 ◽

Author(s):

Thomas Pietri ◽

Benjamin J. Wiley ◽

Jean-Pierre Simonato

Keyword(s):

Boron Nitride ◽

Heat Dissipation ◽

Boron Nitride Nanotubes

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Four-dimensional vibrational spectroscopy for nanoscale mapping of phonon dispersion in BN nanotubes

Nature Communications ◽

10.1038/s41467-021-21452-5 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Ruishi Qi ◽

Ning Li ◽

Jinlong Du ◽

Ruochen Shi ◽

Yang Huang ◽

...

Keyword(s):

Boron Nitride ◽

Energy Loss ◽

Phonon Dispersion ◽

Hexagonal Boron Nitride ◽

Real Space ◽

Boron Nitride Nanotubes ◽

Detection Sensitivity ◽

Optical Modes ◽

Optical And Mechanical Properties ◽

Energy And Momentum

AbstractDirectly mapping local phonon dispersion in individual nanostructures can advance our understanding of their thermal, optical, and mechanical properties. However, this requires high detection sensitivity and combined spatial, energy and momentum resolutions, thus has been elusive. Here, we demonstrate a four-dimensional electron energy loss spectroscopy technique, and present position-dependent phonon dispersion measurements in individual boron nitride nanotubes. By scanning the electron beam in real space while monitoring both the energy loss and the momentum transfer, we are able to reveal position- and momentum-dependent lattice vibrations at nanometer scale. Our measurements show that the phonon dispersion of multi-walled nanotubes is locally close to hexagonal-boron nitride crystals. Interestingly, acoustic phonons are sensitive to defect scattering, while optical modes are insensitive to small voids. This work not only provides insights into vibrational properties of boron nitride nanotubes, but also demonstrates potential of the developed technique in nanoscale phonon dispersion measurements.

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