Nanotechnology

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NANOTECHNOLOGY PRESENTED BY: NITESH KUMAR SINGH BME(7 TH SEM)

Transcript of Nanotechnology

  • 1.PRESENTED BY: NITESH KUMAR SINGH BME(7TH SEM)

2. SO WHAT IS NANO? NANO is a GREEK word meaning EXTREMELY SMALL. Nanotechnology deals with sizes from 1-100nm range A nanometer is very very small its 10-9 m. 3. So what is nanotechnology? 4. Definition Nanotechnology (sometimes shortened to "nanotech") is the study of manipulating matter on an atomic and molecular scale. Generally, nanotechnology deals with developing materials, devices, or other structures possessing at least one dimension sized from 1 to 100 nanometers. 5. ORIGIN Although nanotechnology is a relatively recent development in scientific research, the development of its central concepts happened over a longer period of time. The emergence of nanotechnology in the 1980s was caused by the convergence of experimental advances such as the invention of the scanning tunneling microscope in 1981 and the discovery of fullerenes in 1985 6. S h o r t h i s t o ry1959 Feynman gives after-dinner talk describing molecular machines building with atomic precision 1974 Taniguchi uses term "nano-technology" in paper on ion-sputter machining 1977 Drexler originates molecular nanotechnology concepts at MIT 1981 First technical paper on molecular engineering to build with atomic precision STM invented 1985 Buckyball discovered 1986 First book published AFM invented First organization formed 7. S h o r t h i s t o ry1987 First protein engineered First university symposium 1988 First university course 1989 IBM logo spelled in individual atoms First national conference DNA-based 'robotic' assembly begins Feynman Prize in Nanotechnology awarded for work in single atom manipulations and atomic switches, and for development of quantum mechanical methods for theoretical predictions of molecules and solids 2011molecular robots learn to walk in any direction along a branched track Mechanical manipulation of silicon dimers on a silicon surface 8. APPROACHES Top down approachBottom up approach It refers to the traditional It refers to methods wherework shop or microfabrication method where tools are used to cut, mill and shape materials into the desired shape and orderdevices create themselves by self assembly chemical synthesis is a good example. This approach is much cheaper than top down but dificult to handle becaus things become larger and more bulky. 9. APPROACHES 10. Branches of nanotechnology Green nanotech use of nanotechnology to enhance the environmental-sustainability of processes currently producing negative externalities. It also refers to the use of the products of nanotechnology to enhance sustainability.Wet nanotechnology involves working up to large masses from small ones.Nanoengineering practice of engineering on the nanoscale.Nanobiotech intersection of nanotechnology and biology.10 11. APPLICATIONS OF NANOTECHNOLOGY 12. Nanomedicine - drug delivery - surgery - cancer treatment - medical robotics Nanoelectronics Energy applications Nanomaterial applications Industrial applications - textile - food - cosmetics - transportation - national safety - water pollution - space 13. Nanotechnology in Medicine Applications of medical nanotechnology span across a variety of areas such as In Drugs, Medicines, Therapeutics, etc In Diagnostics of diseases, abnormal conditions etc. In Surgery In Medical Robotics In the general sake of increasing knowledge of the human body 14. Drug Delivery The basic point to use drug delivery is based upon three facts:a) efficient encapsulation of the drugs, b) successful delivery of said drugs to the targeted region of the body, and c) successful release of that drug there. 15. Surgery With nanotechnology, minute surgical instruments and robots can be made which can be used to perform microsurgeries on any part of the body. Instead of damaging a large amount of the body, these instruments would be precise and accurate, targeting only the area where surgery should be done. Visualization of surgery can also be improved. Instead of a surgeon holding the instrument, computers can be used to control the nanosized surgical instruments. Nanocameras can provide close up visualization of the surgery Less chance of any mistakes or faults Surgery could also be done on tissue, genetic and cellular levels. 16. Cancer Treatment Nanotechnology has been used for the first time todestroy cancer cells with a highly targeted package of "tumor busting" genes. Its benefits:-Deliver nanoparticles directly to the cancer tissues -Minimize undesirable toxicity to the rest of the body -This nanoparticle therapy leads to the extermination of the tumor from the body. -It does not leave Secondary Effects on the body. 17. 1-How nanomedicine can cure cancer 18. Medical Robotics Nano-robotics, although havingmany applications in other areas, have the most useful and variety of uses in medical fields. Potential applications include early diagnosis and targeted drug delivery for cancer, biomedical instrumentation, surgery, pharmacokinetics, monitoring of diabetes, and health care. Future medical nanotechnology expected to employ nanorobots injected into the patient to perform treatment on a cellular level. 19. Miscellaneous Applications of Nanotechnology in Health Snapshots of the human body for better understanding of how it works. The workings of cells, bacteria, viruses etc can be better explored. The causes of relatively new diseases can be found and prevented. Restore vision. Genome sequencing can be made much easier. Biological causes of mental diseases can be monitored and identified. Simple curiosity can be answered. Tissue engineering could also be done using nano-materials. Tissue engineering makes use of artificially stimulated cell proliferation by using suitable nanomaterialbased scaffolds and growth factors. Advances in nanotechnology-based tissue engineering could also lead to life extension in humans and other animals. 20. Nanotechnology in Electronics Branch of Engineering which uses nanometer scaleelements in design of integrated circuits such that one of the three dimensions of the electronic component is in nm. Generally, Nanometer scale refers to electronic circuitsless than 100nm. 1 nm= 10-9 metres 21. Continue.. In solar cells to trap electrons There is great interest in constructingnanoelectronic devices that could detect the concentrations of biomolecules in real time for use as medical diagnostics nanoradio, a radio receiver consisting of a single nanotube, was demonstrated in 2007 In fabrication of ultracapacitors (which have high energy density) 22. NANOWIRES Electrons in nanowires are quantum confined laterallyand thus occupy energy levels that are different from that in bulk materials. Aspect ratios (length-to-width ratio) of 1000 or more Poor conductivity (edge effect) 23. WORLDS SMALLEST TRANSISTOR Graphene Transistor invented by Michelle Simmons 24. Schematic diagram of graphene transistor 25. Nanotechnology in Energy & Environment Energy Production - Clean, less expensive sources enabled by novel nanomaterials and processes Energy Utilization - High efficiency and durable home and industrial lighting - Solid state lighting can reduce total electricity consumption by 10% and cut carbon emission by the equivalent of 28 million tons/year Materials of construction sensing changing conditions and in response, altering their inner structure 26. Batteries and Fuels Companies are currently developing batteries usingnanomaterials These will be as good as new even after sitting on the shelf for decades!! Also, Can be recharged significantly faster than conventional batteries. -Can make the production of fuels from low grade raw materials economical, -increasing the mileage of engines, and -making the production of fuels from normal raw materials more efficient 27. Fuel Cells & Solar Cells Nanotechnology is being used to reduce the cost of catalystsused in fuel cells to produce hydrogen ions from fuel such as methanol and to improve the efficiency of membranes used in fuel cells to separate hydrogen ions from other gases such as oxygen. Companies have developed nanotech solar cells that can be manufactured at significantly lower cost than conventional solar cells. 28. Nanotechnology in Nanomaterials Nonmaterial's are materials possessing particles sizes on the order of a billionthof a meter, nanometer. At this size range, the particles will show some unique properties like quantum size effect, surface effect, and macroscopic-quantum-tunnel effect. Nano structures are the ordered system of one-dimension, two dimension or three dimension constructed or assembled with nanometer scale unit in certain pattern, which basically include nano-spheres, nano-rods, nano-wires, Nano-belts and nanotube. Nonmaterial's include, Clusters of atoms, grains that are less than 100 nm in size, Fibers that are less than 100 nm in diameter,Films that are less 100 nm in thickness, Nano-holes and Composites that are a combination of these. 29. Applications of Nanomaterials 1. Nano materials or nano crystals provide large surface area. Hence they act as better catalysts. 2. Tumors can be detected and located with incredible accuracy. 3. Nano shells can float through the body attaching only to cancer cells. When excited by a laser beam, they give off heat and there by destroy tumor. 4. New borns will have their DNA mapped quickly. 5. Nano technology will enable the delivery of right amount of medicines to the exact spot of the body. 6. Nano technology can create biocompatible joint replacements and artery stents that will last life of the patients. Hence these need not be replaced every few years 30. Carbon Based Nanomaterials The materials in which the Nanocomponent is pure carbon.Example: Carbon Nanotubes (CNT) are sheets of graphite rolled up to make a tube. Due to the large surface area, CNT are interesting media for electrical energy storage. The excellent electrical and mechanical properties of carbon nanotubes like electrical conductivity, heat transmission capacity. Heat stability, high strength or low density make them good candidates for use as fillers and many other applications. Carbon nanotubes and polymers can form foams. Carbon black is currently the most widely used carbon nanomaterial, it has found application in car tyres, antistatic textiles and is used for colour effects. 31. Carbon Nano tubes A carbon nanotube is a structure which seems to be formed by rolling a sheet of graphite into the shapes of a cylindrical tube. Nanotubes are categorized as single-walled nanotubes (SWNT) and multiwalled nanotubes (MWNT). Single-walled nanotubes have a diameter of close to 1 nm, with a tube length that can be many millions of times longer. The structure of a SWNT can be conceptualized by wrapping a one-atom-thick layer of graphite called graphene in to a seamless cylinder. Multi-walled carbon nanotubes consist of multiple concentric nanotube cylinders. Based on the orientations of lattices, nanotubes are of three different types-Armchair, Zigzag and Chiral. 32. Carbon nanotubes 33. Properties of Carbon Nanotubes 1. Carbon nanotubes are very strong. 2. Their tensile strength is 100 times greater than that of steel of the same diameter. 3. Youngs modulus is about 5 times higher than for steel. 4. They have high thermal conductivity-more than 10 times that of silver.5. They conduct electricity better than metals. 6. Electron travelling through a carbon nanotube behaves like wave travelling through a smooth channel. This movement of electrons within a nanotube is called ballistic transport. 7. They are light weight, density about one fourth of steel. 8. They are sticky due to Van der Waals force of attraction. 34. Applications of Carbon Nanotubes 1. They are strengtheners of composite materials. 2. They act as molecular size test tubes or capsules for drug delivery 3. Depending on their size, they act as electrical conductors or semiconductors. 4. They are used as tips for analysis of DNA and proteins by atomic force microscopy. 35. Nanotechnology in Textile 36. The use of engineered nanofibers already makes clothes water- and stain-repellent or wrinkle-free. Textiles with a nanotechnological finish can be washed less frequently and at lower temperatures. Nanotechnology has been used to integrate tiny carbon particles membrane and guarantee fullsurface protection from electrostatic charges for the wearer. Many other applications have been developed by research institutions such as the Textiles Nanotechnology Laboratory at Cornell University, and the UK's Dstl and its spin out company 37. Disadvantages of wrinkle free cloth To impart wrinkle resistance to fabric, resin is commonly used in conventional methods. However, there are limitations to applying resin, including a decrease in the tensile strength of fiber, abrasion resistance, water absorbency and dye ability, as well as breathability. Besides wrinkle-free clothing wearers are at risk for a skin condition called contact dermatitis, which can cause itchy skin, rashes and blisters, and it poses serious health implications for people who work with the chemical in factories. To overcome the limitations of using resin, some researchers employed nano-titanium dioxide and nanosilica to improve the wrinkle resistance of cotton and silk respectively. 38. Nanotechnology in Food 39. Nanotechnology in Cosmetics One field of application is in sunscreens. The traditional chemical UV protection approach suffers from its poor long-term stability. A sunscreen based on mineral nanoparticles such as titanium oxide offer several advantages. Titanium oxide nanoparticles have a comparable UV protection property as the bulk material, but lose the cosmetically undesirable whitening as the particle size is decreased. 40. Nanotechnology In Transportation Thermal barrier and wear resistant coatings High strength, light weight composites for increasing fuelefficiency High temperature sensors for under the hood Improved displays Battery technology Wear-resistant tires Automated highways 41. Nanotechnology in National Security Very high sensitivity, low power sensor for detecting the chem/bio/nuclear threats. Light weight military platforms, without sacrificing functionality, safety and soldier security -Reduce fuel needs and logistical requirements Reduce carry-on weight of soldier gear -Increased functionality per unit weight 42. Nanotechnology in Water Pollution Being used to develop solutions to different problemsin water quality. One challenge is the removal of industrial wastes, such as a cleaning solvent called TCE, from groundwater. Nanoparticles can be used to convert the contaminating chemical through a chemical reaction to make it harmless. Studies have shown that this method can be used successfully to reach contaminates dispersed in underground ponds and at much lower cost than methods which require pumping the water out of the ground for treatment 43. Nanotechnology in Space Nanotechnology may hold the key to making space flight more practical. Advancements in nonmaterial make lightweight solar sails and a cable for the space elevator possible. By significantly reducing the amount of rocket fuel required, these advances could lower the cost of reaching orbit and traveling in space. In addition, new materials combined with nanosensors and nanorobots could improve the performance of spaceships, spacesuits, and the equipment used to explore planets and moons, making nanotechnology an important part of the final frontier. 44. Gone are the days of huge spaceships that cost a fortune! 45. Use of technology in space Carbon nanotubes are the perfect choice for such an elevators cable, since nanotechnology is able to create carbon-based material that is light in weight yet strong enough to withstand the forces it would face in space. A space elevator would make all kinds of pioneering efforts possible by dramatically reducing the cost of sending things into orbit. This becomes painfully obvious when one considers that 95% of a space shuttles takeoff weight is entirely devoted to fuel storage. 46. MERITS AND DEMERITS OF NANOTECHNOLOGY Merits of nanotechnology:* It is an enabling technology which has its impacts on electronics and computing, materials and manufacturing, etc. * Large scale production of materials * Great job opportunities * Effective and cheap production of energy * Water conservation * Reduced pollution 47. Demerits of nanotechnology:* Nanoparticles have the possibility of breaking into blood-brain barrier - a membrane to protect brain from harmful chemicals in blood stream * Creation of powerful weapons - lethal & non-lethal * Nano-divide [technological and economical differences between rich and poor] * Loss of traditional methods * Increase in aristocracies and reduce democracies * Brain drain and trade barriers * Black market in nanotech * Free range self-replication 48. Nanotechnology as Career It is a powerful profession which aids the development of products with futuristic performance. All field sectors of life will be effected by this new area. The two field categories of Nanotechnology are Nanoscale profession and Molecular manufacturing. Nanoscale profession covers small structures and crapper be used for introducing stronger materials, meliorate medicines, faster computers and so on. Molecular manufacturing is an attempt at building mechanical and chemical manufacturing systems that join molecules together. 49. Thanking You