Carbon nanotubes
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Carbon nanotubes were discovered in 1991 and come in two main types: single-walled and multi-walled. They have a unique cylindrical structure that gives them remarkable electronic, thermal, and structural properties depending on their structure. There are several methods for synthesizing carbon nanotubes, such as arc discharge, chemical vapor deposition, and laser ablation, each with their own advantages and disadvantages related to yield, purity, and scalability. Carbon nanotubes have many potential applications due to their low density, high strength, and ability to conduct heat and electricity well. However, they are also very expensive to produce and questions remain about their environmental and health impacts.
![• Low Density
• High Tensile Strength
• High Resillence
• High Current Carrying Capacity
• High Heat Transmission
• High Temperature Stability
• High Cost [Sorting, Purification]](https://image.slidesharecdn.com/glnur-carbonnantubessunum-141204082845-conversion-gate01/85/Carbon-nanotubes-12-320.jpg)
Carbon nanotubes
- 1. HACETTEPE UNIVERSITY MATERIAL SCIENCE AND ENGINEERING
- 3. • Carbon Nanotubes, long, thin cylinders of carbon, were discovered in 1991 by Sumio Lijima. • Unique size, shape, and remarkable physical properties. • Very broad range of electronic, thermal, and structural properties that change depending on the different kinds of nanotube.
- 5. Most single-walled nanotubes (SWNT) have a diameter of close to 1 nanometre, with a tube length that can be many millions of times longer.
- 7. • ZIGZAG • ARMCHAIR • CHIRAL
- 8. Multi-walled nanotubes (MWNT) consist of multiple rolled layers (concentric tubes) of graphite.
- 9. • A carbon nanotube contains another nanotube inside it (the inner nanotube has a smaller diameter than the outer nanotube) Parchment Model • A single graphene sheet is rolled around itself multiple times, resembling a rolled up scroll of paper
- 11. Technique Arc Discharge CVD Laser Ablation Yield 30 to 90 % 20 to 100 % Up to 70 % Advantages  SWNT’s with few defects  MWNTs without catalyst  Relatively cheap  Open air Synthesis possible  Easiest to scale up  Simple process  Long length  SWNT diameter is controllable  Quite pure  Primarily SWNTs with good diameter control and few defects  Quite pure Disadvantages o Randomly short tube sizes and directions o Often needs purification o Usually MWNTs o Often riddled with defects o Costly technique because of expensive lasers o High power requirement
- 12. • Low Density • High Tensile Strength • High Resillence • High Current Carrying Capacity • High Heat Transmission • High Temperature Stability • High Cost [Sorting, Purification]
- 13. Small and lightweight Resistant to temperature changes Improvement for plastics and composites Clean, bulk micromachining and assembly of components
- 14. Working principles are mystery Difficult to work with Expensive to produce Enviromental concerns