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EE 3219. Electrical Engineering Materials. Dr. Md. Sherajul Islam Associate Professor. Department of Electrical and Electronics Engineering Khulna University of Engineering & Technology Khulna, Bangladesh. LECTURE - 6. Nanotechnology and Nanomaterials. Nanotechnology
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EE 3219 Electrical Engineering Materials • Dr. Md. Sherajul Islam • Associate Professor Department of Electrical and Electronics Engineering Khulna University of Engineering & Technology Khulna, Bangladesh
LECTURE - 6 Nanotechnology and Nanomaterials
Nanotechnology The art and science of manipulating and rearranging individual atoms and molecules to create useful materials, devices, and systems The design, characterization, and application of structures, devices, and systems by controlled manipulation of size and shape of materials at the nanometer scale (atomic, molecular, and macromolecular scale)
Nanoscale? • A sheet of paper is about 100,000 nanometers thick, a human hair is around 80,000- 100,000 nanometers wide
1.1.2- What is nanomaterial? • Is defined as any material that has unique or novel properties, due to the nanoscale ( nano metre- scale) structuring. • These are formed by incorporation or structuring of nanoparticles. • They are subdivided into nanocrystals, nanopowders, and nanotubes: A sequence of nanoscale of C60 atoms arranged in a long thin cylindrical structure.
1.1.2- What is nanomaterial? carbon nanotubes
1.1.2- What is nanomaterial? Noble metal nanocrystals with cyclic penta-twinned structures
1.1.2- What is nanomaterial? Naonpowder
Date, location Types of nanomaterials • Nanomaterials can… • occur naturally • be produced by human activity either as a product of another activity • on purpose (engineered) • Our focus: engineered nanomaterials as these are designed and integrated into products because of the specific characteristics of the nanomaterial
Classes of nanomaterials Date, location
NanoZnO – One Chemistry, Many Shapes Courtesy of Prof. Z.L. Wang, Georgia Tech
Why are nanomaterials used? • At nano-scale, • the material properties change - melting point, fluorescence, electrical conductivity, and chemical reactivity • Surface size is larger so a greater amount of the material comes into contact with surrounding materials and increases reactivity • Nanomaterial properties can be ‘tuned’ by varying the size of the particle (e.g. changing the fluorescence colour so a particle can be identified) • Their complexity offers a variety of functions to products
Examples of nanomaterials in products • Examples: • Amorphous silica fume (nano-silica) in Ultra High Performance Concrete – this silica is normally thought to have the same human risk factors as non‐nano non‐toxic silica dust • Nano platinum or palladium in vehicle catalytic converters - higher surface area to volume of particle gives increased reactivity and therefore increased efficiency • Crystalline silica fume is used as an additive in paints or coatings, giving e.g. self-cleaning characteristics– it has a needle-like structure and sharp edges so is very toxic and is known to cause silicosis upon occupational exposure
Nanotechnology spans many Areas Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Engineering / Robotics Biotechnology Biotechnology Biotechnology Biotechnology Biotechnology Biotechnology Biotechnology Biotechnology Transportation Transportation Transportation Transportation Advance Materials & Textiles Advance Materials & Textiles Advance Materials & Textiles Advance Materials & Textiles Advance Materials & Textiles NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY National Security & Defense National Security & Defense National Security & Defense National Security & Defense National Security & Defense National Security & Defense Energy & Environment Energy & Environment Energy & Environment Energy & Environment Energy & Environment Energy & Environment Energy & Environment Energy & Environment Energy & Environment Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace
2.2- Environmental ApplicationsCheck http://www.nanowerk.com/products/product.php?id=160 for more details