boron nitride nanotube
TRANSCRIPT
Boron Nitride Nanotube
A pioneer of revolutionary material
Md. Mirza Anam ShawonStudent ID:1311042Materials And Metallurgical Engineering
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Overview
Introduction
Properties
ComparisonSynthesis
Processing
ApplicationConclusion
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Introduction• Boron Nitride Nanotubes (BNNT), firstly synthesized in 1995.Invention
• BNNTs are structural analogues of carbon nanotubes with boron and nitrogen atoms instead of carbon atoms.Combination
• BNNTs can be imagined as a rolled up hexagonal BN layer or as a carbon nanotube (CNTs) in which alternating B and N atoms entirely substitute for C atoms.
Substitution
• Similar to CNTs, BNNTs also have chiralities but the chiralities do not play a significant role in determining electrical properties.
Chirality
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PropertiesBand Gap
Sensitivity
Insulator
Electrical Properties
Chemical Properties
•Uniform band gap (5.5 eV)
•High sensitivity for sensor materials
•Unusually efficient electric insulator
•electrically isolating materials with uniform electronics properties
•Inert •Oxidation resistant
List // Comparison
CNTS vs
BNNTs
Thermal Oxidation
Electrical Properties
PolarityAppearance
MechanicalProperties
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List // Synthesis Method Arc Discharge
Laser Ablation
BallMilling
Chemical Vapour Deposition
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Processing
•Amorphous B powder + NH3
Flowing atm of N2
• Addition of fine Fe catalyst particles
Prior to heat treatment • Synthesized product
+ hydrocarbon solvent + ceramic grinding media
Milling in polyethylene
bottle
•Addition of Al, SiC, Pt, Mo with milled material
Adding substrates•Temperature ranging from 1100 C to 1400 C
•Final product
Heat Treatment
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Applications
• BNNT is not cytotoxic.• Useful in nano-textured cellular scaffolding for nerve and bone tissue regeneration.• Nanoscale drug vectors and delivery structures.• Electroporation-based oncology (cancer) therapies.
• A new generation of lightweight ceramic composites.• A wide range of high temperature applications in systems such as jet engines. • Low temperature applications could include dentistry.
Biomedical
Ceramic Composites
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• This arena of BNNT enhanced composites is anticipated to have exceptional strength and thermal conductivity far beyond what currently exists in the market place.• Potential applications are present in areas such as armor including transparent armor, thin coatings, batteries and aerospace components.
• Outstanding piezoelectric and electrostrictive properties are observed for BNNT. • This combined with their exceptional strength will allow creation of nontoxic lightweight piezoelectric systems with better response and mechanical properties than current piezoelectric polymers.• BNNT will be key to enhanced sensors and robotics including applications in Unmanned Aerial Vehicles, harvesting energy and satellites.
Polymer Composites
Piezoelectric
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• Flame resistant high strength cabling will soon become available in applications for use in expanded ranges of temperatures and extreme operational environments. • Including CNT cores will create a new level of high strength lightweight conductive cables.
• Thermally conductive and electrically insulating components will be possible with new BNNT ultra strong composites. • Anticipated applications range from lightweight wiring for aerospace systems, to enhanced cooling of electronic components, to high performance batteries
Fire Retardant Cabling
Electrically Insulating
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• BNNT can be the basis for neutron shielding composites for use in radiation shielding applications due to the presence of boron with its unique high efficiency for absorbing thermal neutrons.• BNNT can also be used for ultra violet (UV) shielding applications.
Radiation Shielding
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Conclusion• Super-strong textile-like nanotubes with the appearance of cotton, the material has a molecular backbone 100 times stronger
than steel. • Boron Nitride Nanotubes are as strong as the better-known carbon nanotubes, but much more heat resistant - up to 800° C or
1472° F in air.• The material also has an intrinsic piezoelectric function -- meaning it creates electricity resulting from stretching or twisting. • This and other characteristics of the multi-functional nanotube make the technology a prime candidate for applications ranging
from heat shields for the next generation of spacecraft, to new water filtration capabilities - even potential cancer therapies.
Boron nitride nanotubes - a new revolutionary chapter in a nanotechnology
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