 UNIVERSITY OF ENGINEERING AND MANAGEMENT,JAIPUR,RAJASTHAN
TOPIC: NANO TUBES
BRANCH ECE
* SOUDIP SINHA ROY .
.
LIST OF DISCUSSION
CARBON NANOTUBE BORON
NANOTUBE
CARBON NANOTUBES
DAVID MCDERMOTT
JAKE BORRAJO
PHYS43 MODERN PHYSICS, SRJC
SECTION 5756
INSTRUCTOR: DR. YOUNES ATAIIYAN
MOD...
WHAT ARE CARBON
NANOTUBES.•CARBON NANOTUBES (CNTS) ARE
ALLOTROPES OF CARBON. THESE
CYLINDRICAL CARBON MOLECULES HAVE
INTER...
HOW CNTS ARE MADE
• ARC DISCHARGE
• CNTS CAN BE FOUND IN THE CARBON SOOT OF
GRAPHITE ELECTRODES DURING AN ARC DISCHARGE
IN...
PROPERTIES
• STRENGTH
• ELECTRICAL
• THERMAL
• DEFECTS
• ONE-DIMENSIONAL TRANSPORT
• TOXICITY
STRENGTH PROPERTIES
• CARBON NANOTUBES HAVE THE STRONGEST TENSILE
STRENGTH OF ANY MATERIAL KNOWN.
• IT ALSO HAS THE HIGHES...
ELECTRICAL PROPERTIES
• IF THE NANOTUBE STRUCTURE IS
ARMCHAIR THEN THE ELECTRICAL
PROPERTIES ARE METALLIC
• IF THE NANOTUB...
THERMAL PROPERTIES
• ALL NANOTUBES ARE EXPECTED TO BE VERY GOOD THERMAL
CONDUCTORS ALONG THE TUBE, BUT GOOD INSULATORS
LAT...
DEFECTS
• DEFECTS CAN OCCUR IN THE FORM OF ATOMIC
VACANCIES. HIGH LEVELS OF SUCH DEFECTS CAN
LOWER THE TENSILE STRENGTH BY...
ONE-DIMENSIONAL TRANSPORT
• DUE TO THEIR NANOSCALE DIMENSIONS, ELECTRON
TRANSPORT IN CARBON NANOTUBES WILL TAKE
PLACE THRO...
APPLICATIONS
• NANOTUBES HOLD THE PROMISE OF CREATING NOVEL
DEVICES, SUCH AS CARBON-BASED SINGLE-ELECTRON
TRANSISTORS, THA...
NANOTUBES’ EXCELLENT STRENGTH TO WEIGHT RATIO
CREATES THE POTENTIAL
TO BUILD AN ELEVATOR TO
SPACE.
QUANTUM COMPUTING
• NANOTUBES AND OTHER FULLERENES CAN BE FILLED WITH
MOLECULES THAT HAVE EITHER AN ELECTRONIC OR
STRUCTUR...
HEALTH HAZARDS
• ACCORDING TO SCIENTISTS AT THE NATIONAL INSTITUTE OF
STANDARDS AND TECHNOLOGY, CARBON NANOTUBES
SHORTER T...
BORON NANOTUBE
Scientists used to think know everything about this element, and since it was not in great
demand in industry boron was ou...
THERE IS NO CONSENSUS ABOUT HOW MANY BORON
MODIFICATIONS EXIST.
• RESEARCHERS (BORIS
YAKOBSON) ANTICIPATED THE
EXISTENCE O...
ONE OF THE CONFIGURATIONS OF BORON –
HEXAGONAL BORON
FIG. 1.BORON STRUCTURE.
• TABLE 1. MAIN PROPERTIES OF QUASI-
PLANAR H...
BY ANALOGY WITH CARBON NANOTUBES WE
ASSUMED THAT BORON NANOTUBES CAN BE
CONSTRUCTED BY ROLLING OF HEXAGONAL
QUASI-PLANAR B...
BORON NANO TUBES WITH DEFECTS
BORON NANOTUBE WITH SUBSTITUTION DEFECTS (EITHER NEUTRAL CARBON
ATOM (С), OR POSITIVELY (С+)...
SORPTION PROPERTIES OF BORON
NANOTUBES
• IT IS KNOWN THAT BORON NANOTUBES HAVE
UNIQUE SOPTION PROPERTIES. MUCH
RESEARCH IN...
REFERENCES
• HTTP://WWW.NEWS-MEDICAL.NET/NEWS/22799.ASPX
• CHAE, H.G.; KUMAR, S. (2006). "RIGID ROD POLYMERIC FIBERS".
JOU...
Nano tubes Modern Technology
Nano tubes Modern Technology
of 25

Nano tubes Modern Technology

Published on: Mar 3, 2016
Published in: Engineering      
Source: www.slideshare.net


Transcripts - Nano tubes Modern Technology

  • 1.  UNIVERSITY OF ENGINEERING AND MANAGEMENT,JAIPUR,RAJASTHAN TOPIC: NANO TUBES BRANCH ECE * SOUDIP SINHA ROY . .
  • 2. LIST OF DISCUSSION CARBON NANOTUBE BORON NANOTUBE
  • 3. CARBON NANOTUBES DAVID MCDERMOTT JAKE BORRAJO PHYS43 MODERN PHYSICS, SRJC SECTION 5756 INSTRUCTOR: DR. YOUNES ATAIIYAN MODERN PHYSICS PROJECT
  • 4. WHAT ARE CARBON NANOTUBES.•CARBON NANOTUBES (CNTS) ARE ALLOTROPES OF CARBON. THESE CYLINDRICAL CARBON MOLECULES HAVE INTERESTING PROPERTIES THAT MAKE THEM POTENTIALLY USEFUL IN MANY APPLICATIONS IN NANOTECHNOLOGY, ELECTRONICS, OPTICS AND OTHER FIELDS OF MATERIALS SCIENCE, AS WELL AS POTENTIAL USES IN ARCHITECTURAL FIELDS. THEY EXHIBIT EXTRAORDINARY STRENGTH AND UNIQUE ELECTRICAL PROPERTIES, AND ARE EFFICIENT CONDUCTORS OF HEAT. THEIR FINAL USAGE, HOWEVER, MAY BE LIMITED BY THEIR POTENTIAL TOXICITY.
  • 5. HOW CNTS ARE MADE • ARC DISCHARGE • CNTS CAN BE FOUND IN THE CARBON SOOT OF GRAPHITE ELECTRODES DURING AN ARC DISCHARGE INVOLVING HIGH CURRENT. THIS PROCESS YIELDS CNTS WITH LENGTHS UP TO 50 MICRONS. • LASER ABLATION • IN THE LASER ABLATION PROCESS, A PULSED LASER VAPORIZES A GRAPHITE TARGET IN A HIGH- TEMPERATURE REACTOR WHILE AN INERT GAS IS INSERTED INTO THE REACTOR. NANOTUBES DEVELOP ON THE COOLER SURFACES OF THE REACTOR AS THE VAPORIZED CARBON CONDENSES. • OTHER METHODS WHERE CNTS ARE CREATED: - CHEMICAL VAPOR DECOMPOSITION - NATURAL, INCIDENTAL, AND CONTROLLED FLAME ENVIRONMENTS
  • 6. PROPERTIES • STRENGTH • ELECTRICAL • THERMAL • DEFECTS • ONE-DIMENSIONAL TRANSPORT • TOXICITY
  • 7. STRENGTH PROPERTIES • CARBON NANOTUBES HAVE THE STRONGEST TENSILE STRENGTH OF ANY MATERIAL KNOWN. • IT ALSO HAS THE HIGHEST MODULUS OF ELASTICITY. Material Young's Modulus (TPa) Tensile Strength (GPa) Elongation at Break (%) SWNT ~1 (from 1 to 5) 13-53E 16 Armchair SWNT 0.94T 126.2T 23.1 Zigzag SWNT 0.94T 94.5T 15.6-17.5 Chiral SWNT 0.92 MWNT 0.8-0.9E 150 Stainless Steel ~0.2 ~0.65-1 15-50 Kevlar ~0.15 ~3.5 ~2
  • 8. ELECTRICAL PROPERTIES • IF THE NANOTUBE STRUCTURE IS ARMCHAIR THEN THE ELECTRICAL PROPERTIES ARE METALLIC • IF THE NANOTUBE STRUCTURE IS CHIRAL THEN THE ELECTRICAL PROPERTIES CAN BE EITHER SEMICONDUCTING WITH A VERY SMALL BAND GAP, OTHERWISE THE NANOTUBE IS A MODERATE SEMICONDUCTOR • IN THEORY, METALLIC NANOTUBES CAN CARRY AN ELECTRICAL CURRENT DENSITY OF 4×109 A/CM2 WHICH IS MORE THAN 1,000 TIMES GREATER THAN METALS SUCH AS COPPER
  • 9. THERMAL PROPERTIES • ALL NANOTUBES ARE EXPECTED TO BE VERY GOOD THERMAL CONDUCTORS ALONG THE TUBE, BUT GOOD INSULATORS LATERALLY TO THE TUBE AXIS. • IT IS PREDICTED THAT CARBON NANOTUBES WILL BE ABLE TO TRANSMIT UP TO 6000 WATTS PER METER PER KELVIN AT ROOM TEMPERATURE; COMPARE THIS TO COPPER, A METAL WELL- KNOWN FOR ITS GOOD THERMAL CONDUCTIVITY, WHICH TRANSMITS 385 WATTS PER METER PER K. • THE TEMPERATURE STABILITY OF CARBON NANOTUBES IS ESTIMATED TO BE UP TO 2800OC IN VACUUM AND ABOUT 750OC IN AIR.
  • 10. DEFECTS • DEFECTS CAN OCCUR IN THE FORM OF ATOMIC VACANCIES. HIGH LEVELS OF SUCH DEFECTS CAN LOWER THE TENSILE STRENGTH BY UP TO 85%. • BECAUSE OF THE VERY SMALL STRUCTURE OF CNTS, THE TENSILE STRENGTH OF THE TUBE IS DEPENDENT ON ITS WEAKEST SEGMENT IN A SIMILAR MANNER TO A CHAIN, WHERE THE STRENGTH OF THE WEAKEST LINK BECOMES THE MAXIMUM STRENGTH OF THE CHAIN.
  • 11. ONE-DIMENSIONAL TRANSPORT • DUE TO THEIR NANOSCALE DIMENSIONS, ELECTRON TRANSPORT IN CARBON NANOTUBES WILL TAKE PLACE THROUGH QUANTUM EFFECTS AND WILL ONLY PROPAGATE ALONG THE AXIS OF THE TUBE. BECAUSE OF THIS SPECIAL TRANSPORT PROPERTY, CARBON NANOTUBES ARE FREQUENTLY REFERRED TO AS “ONE-DIMENSIONAL.”
  • 12. APPLICATIONS • NANOTUBES HOLD THE PROMISE OF CREATING NOVEL DEVICES, SUCH AS CARBON-BASED SINGLE-ELECTRON TRANSISTORS, THAT SIGNIFICANTLY SMALLER THAN CONVENTIONAL TRANSISTORS.
  • 13. NANOTUBES’ EXCELLENT STRENGTH TO WEIGHT RATIO CREATES THE POTENTIAL TO BUILD AN ELEVATOR TO SPACE.
  • 14. QUANTUM COMPUTING • NANOTUBES AND OTHER FULLERENES CAN BE FILLED WITH MOLECULES THAT HAVE EITHER AN ELECTRONIC OR STRUCTURAL PROPERTY WHICH CAN BE USED TO REPRESENT THE QUANTUM BIT (QUBIT) OF INFORMATION, AND WHICH CAN BE ASSOCIATED WITH OTHER ADJACENT QUBITS.
  • 15. HEALTH HAZARDS • ACCORDING TO SCIENTISTS AT THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY, CARBON NANOTUBES SHORTER THAN ABOUT 200 NANOMETERS READILY ENTER INTO HUMAN LUNG CELLS SIMILAR TO THE WAY ASBESTOS DOES, AND MAY POSE AN INCREASED RISK TO HEALTH. • CARBON NANOTUBES ALONG WITH THE MAJORITY OF NANOTECHNOLOGY, ARE AN UNEXPLORED MATTER, AND MANY OF THE POSSIBLE HEALTH HAZARDS ARE STILL UNKNOWN.
  • 16. BORON NANOTUBE
  • 17. Scientists used to think know everything about this element, and since it was not in great demand in industry boron was out of the focus of attention. But in recent decades, boron and its compounds has found application in different industries such as atomic, rocket-building, metal processing, chemical and many others. Boron atoms are capable of forming both ion and covalent bonds. They can make chains, frames, nets etc. Still, we do not know much about this element. Boron has found application in many fields of modern technology.  small addition of boron to steel (0,0005…0,005 %) increase its hardness!  Boron better than any other element removes gases from copper that improve its properties. Saturation of metals with boron forms hard borids! «We need to know much to understand how little we know»
  • 18. THERE IS NO CONSENSUS ABOUT HOW MANY BORON MODIFICATIONS EXIST. • RESEARCHERS (BORIS YAKOBSON) ANTICIPATED THE EXISTENCE OF A FULLERENE CONSISTING OF 80 BORON ATOMS. • BORON NANOTUBES WERE SYNTHESISED RECENTLY AND THEIR PROPERTIES AND NATURE HAVE NOT BEEN FULLY REVEALED. __________________________________________________________________________________________________
  • 19. ONE OF THE CONFIGURATIONS OF BORON – HEXAGONAL BORON FIG. 1.BORON STRUCTURE. • TABLE 1. MAIN PROPERTIES OF QUASI- PLANAR HEXAGONAL BORON. The number of atoms в EEC Atom charge Ionazation potential, eV 64 0 7.31 80 0 7.25 88 0 7.95 96 0 8.08 108 0 8.13
  • 20. BY ANALOGY WITH CARBON NANOTUBES WE ASSUMED THAT BORON NANOTUBES CAN BE CONSTRUCTED BY ROLLING OF HEXAGONAL QUASI-PLANAR BORON DUE TO THREE-CENTER BONDING BORON NANOTUBES ARE MAINLY OF TRIANGULAR AND HEXAGONAL TYPES.
  • 21. BORON NANO TUBES WITH DEFECTS BORON NANOTUBE WITH SUBSTITUTION DEFECTS (EITHER NEUTRAL CARBON ATOM (С), OR POSITIVELY (С+) AND NEGATIVELY (С–) CHARGED CARBON IONS)
  • 22. SORPTION PROPERTIES OF BORON NANOTUBES • IT IS KNOWN THAT BORON NANOTUBES HAVE UNIQUE SOPTION PROPERTIES. MUCH RESEARCH INTO THE MECHANISM OF ATOM AND MOLECULAR ADSORPTION ON THEIR SURFACE HAS BEEN CARRIED OUT. • THE STUDY OF THE SURFACE STRUCTURE HYDROGENATION IS PROMISING FOR ITS APPLICATION AS A STORAGE FOR MOLECULAR HYDROGEN. • THE SEARCH FOR STRUCTURES WITH WELL- DEVELOPED SURFACES CAPABLE OF ADSORBING GASES (INCLUDING HYDROGEN) REMAINS IN THE FOCUS OF ATTENTION. IN THIS RESPECT RESEARCH OF SORPTION PROPERTIES OF BORON NANOTUBES IS IMPORTANT. ______________________________________________
  • 23. REFERENCES • HTTP://WWW.NEWS-MEDICAL.NET/NEWS/22799.ASPX • CHAE, H.G.; KUMAR, S. (2006). "RIGID ROD POLYMERIC FIBERS". JOURNAL OF APPLIED POLYMER SCIENCE 100:791-802: 791. DOI:10.1002/APP.22680. • HONG, SEUNGHUN; SUNG MYUNG (2007). "NANOTUBE ELECTRONICS: A FLEXIBLE APPROACH TO MOBILITY". NATURE NANOTECHNOLOGY 2: 207–208. DOI:10.1038/NNANO.2007.89 • MEO, S.B.; ANDREWS R. (2001). "CARBON NANOTUBES: SYNTHESIS, PROPERTIES, AND APPLICATIONS". CRIT. REV. SOLID STATE MATER. SCI. 26(3):145-249: 145. DOI:10.1080/20014091104189. • KOLOSNJAJ J, SZWARC H, MOUSSA F (2007). "TOXICITY STUDIES OF CARBON NANOTUBES". ADV EXP MED BIOL. 620: 181–204. PMID 18217344 • EBBESEN, T. W.; AJAYAN, P. M. (1992). "LARGE-SCALE SYNTHESIS OF CARBON NANOTUBES". NATURE 358: 220–222. DOI:10.1038/358220A0

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