Nanotechnology and its Economic Feasibility

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These slides apply the concepts from my course (Analyzing Hi-Tech Opportunities) to the field of nano-technology. Like the reductions in the feature sizes of transistors and metal lines on ICs (integrated circuits), in the micro-fluidic channels on bio-electronic ICs, and in the features of MEMS (micro-electronic mechanical systems), many physical phenomena become pronounced as the feature size decreases. Carbon nano-tubes, grapheme, quantum dots, nano-particles, and nano-fibers are examples of materials that benefit from small sizes. On the other hand, reductions in costs must be addressed through increases in the scale of production equipment and the creation of better processes; similar things occurred with other technologies such as displays and lighting.

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  • After looking at the market demand of CNT, we’d want to know how much does CNT cost if we were to use it as raw material,Our team has been searching hi and low for the pricing trend of CNT but found out that most of the source are charging at least a few hundred dollars for it.Hence, based on various reports and all the possible information which we could get hold of, we plotted them into the nice looking graph with colourful data points.This graph shows the price trends of various materials such as CNTs (SWCNT, MWCNT), Indium, carbon fibre and steel when they are in mass production in terms of multi tonnes.First, we see that CNTs are becoming cheaper over the years and are currently in 2013, already cheaper than Indium, a material that’s used to produce TE by almost 8times.Secondly, though they are now still much more expensive than Carbon fibre (approximately 8 times), however, with its decreasing trend, we are confident that CNTs will be able to catch up with the price of carbon fibre in the near future.Then at the bottom of the graph, you can see that steel is hovering less than 1/thousandth of a dollar per gram which is relatively stable nowadays.It is at this price that we’d say, a very ambitious target that we foresee CNT would arrive at in the long term, not sure how long it’ll take, BUT there’re possibilities (these, I will show you in a short while)www.cheaptubesinc.com/carbon-nanotubes-prices.htmwww.helixmaterial.comNanotechnology by Ben Rogers, Sumita Pennathur, Jesse Adams, CRC Pres,s 2011New Methods for Continuous Production of Carbon Nanotubes, Science Daily, Apr. 10, 2012www.minerals.usgs.govhttp://www.ptonline.com/articles/carbon-nanotubes-lots-of-potentialif-the-price-is-righthttp://www.prnewswire.com/news-releases/production-and-application-of-carbon-nanotubes-carbon-nanofibers-fullerenes-graphene-and-nanodiamonds-a-global-technology-survey-and-market-analysis-131970098.html12% from 2012 to 2016Carbon fibre on 25 Sep 2013 -http://www.mypurchasingcenter.com/commodities/commodities-articles/carbon-fiber-prices-more-competitive/Carbon fibre 2011 - http://www.rmi.org/RFGraph-carbonfiber_vs_steel_manufacturinghttp://gizmodo.com/5843276/why-is-carbon-fiber-so-expensiveSteel - http://www.mypurchasingcenter.com/commodities/commodities-articles/steel-price-forecast-2014/Steel - http://www.meps.co.uk/World%20Carbon%20Price.htm
  • Nanotechnology and its Economic Feasibility

    1. 1. A/Prof Jeffrey Funk Division of Engineering and Technology Management National University of Singapore When Will NanoTechnology-Based Products Become Economically Feasible for Specific Applications? For information on other technologies, see http://www.slideshare.net/Funk98/presen
    2. 2. Session Technology 1 Objectives and overview of course 2 Two types of improvements: 1) Creating materials that better exploit physical phenomena; 2) Geometrical scaling 4 Semiconductors, ICs, electronic systems 5 MEMS and Bio-electronic ICs 6 Nanotechnology and DNA sequencing 7 Superconductivity and solar cells 8 Lighting and Displays 9 Human-computer interfaces (also roll-to roll printing) 10 Telecommunications and Internet 11 3D printing and energy storage This is Part of the Sixth Session of MT5009
    3. 3. Objectives  What are the important dimensions of performance for nanotechnologies and their higher level systems?  What are the rates of improvement?  What drives these rapid rates of improvement?  Will these improvements continue?  What kinds of new systems will likely emerge from the improvements in nanotechnology?  What does this tell us about the future?
    4. 4. As Noted in Previous Session, Two main mechanisms for improvements  Creating materials (and their associated processes) that better exploit physical phenomenon  Geometrical scaling  Increases in scale  Reductions in scale  Some technologies directly experience improvements while others indirectly experience them through improvements in ―components‖ A summary of these ideas can be found in 1) What Drives Exponential Improvements? California Management Review, Spring 2013 2) Technology Change and the Rise of New Industries, Stanford University Press, 2013 3) Exponential Change: what drives it? What does it tell us about the future?
    5. 5. Both are Relevant to Nanotechnology  Creating materials (and their associated processes) that better exploit physical phenomenon  Creating materials such as carbon nanotubes that better exploit small dimensions  Geometrical scaling  Increases in scale: larger production equipment  Reductions in scale: exploiting phenomena at small dimensions; ability to create smaller dimensions enables more phenomena to be exploited. Some people argue that ―thin film‖ is part of every important technology  Some technologies directly experience improvements while others indirectly experience them through improvements in ―components‖  Better nanotechnology-based products lead to better electronic systems
    6. 6. Both Relevant to Nanotechnology (cont)  Rapid improvements in integrated circuits (ICs), magnetic storage, other electronic technologies over last 50 years  Moore‘s Law  Areal recording density of hard disk platters  These improvements have enabled many new forms of electronic products and improvements in them  Computers, Mobile Phones, Internet  Is there a similar or greater potential for nanotechnology?  Are there indications of this potential in a
    7. 7. Outline  What is nanotechnology?  Fullerene, Graphene and Carbon Nanotubes  Quantum Dots  Nanoparticles  Nanofibers  Common issues
    8. 8. What is NanoTechnology? (1)  Things on the nano-meter (10-9) level: 1-100 nm  ICs, MEMS, and bio-electronics can be considered nano-technology  But,  nano-technology should take us to smaller scale, molecular or even atomic level  like ICs, these technologies should benefit from the reductions in scale that these nano-dimensions represent  involve self-assembly (like with snowflakes and biological reproduction) so that the costs of making them are low  Have progress that is measurable and identifiable
    9. 9. http://www.nanostart.de/index.php/en/nanotechnology/tiny-structures-with-a- big-future (Currently, mostly semiconductors and pharmaceuticals) Too Much Hype!!!! http://www.nanowerk. com/spotlight/spotid =1792.php
    10. 10. What is NanoTechnology? (2)  One-dimensional nanoproducts  thin film devices, coatings (antireflection, corrosion), graphene and quantum wells (stacked thin film layers)  found in semiconductor, metallic, and dielectric films  • Two-dimensional (2-D) nanoproducts  single or multiwall nanotubes  nanowires, nanorods  Three-dimensional (3-D) nanoproducts  fullerenes,  dendrimers  nanoparticles  polymeric dispersions
    11. 11. Why do we care? From Large to Small  A number of physical phenomena become pronounced as the size of the system decreases  increase in surface area to volume ratio altering mechanical, thermal and catalytic properties  statistical and quantum mechanical effects at less than 100 nanometers  hydrogen bonding, molecular forces, van der waals forces  Different properties appear at the nano-scale, enabling unique applications  opaque substances become transparent (copper)  stable materials turn combustible (aluminum)  insoluble materials become soluble (gold)  high thermal and electrical conductivities and strength (carbon)
    12. 12. As the size of a particle becomes smaller, van der walls (vdw) forces (i.e., electro- magnetic forces between neutral atoms) become much more important than gravitational forces (earth-particle and particle-particle) Source: Treavor A. Kendall,
    13. 13. Once we have Small Things, How can we Make Big Things?  Top-down approaches are too expensive  Micro-machining  Photolithography  Electron-beam lithography  Focused ion beams  Bottom-up, or so-called self assembly is needed  Modern synthetic chemistry enables synthesis of chemicals from molecules  New methods are needed
    14. 14. Manufacturing Processes are Critical  Processes determine costs and performance of nano- products  Needed characteristics of processes  High purity: often need 99.9999999%  High material yields: low yields are common in many processes such as molecular beam epitaxy (3-10%) or metal organic CVD (theoretical limit is 50%)  Small number of process steps  Low temperature and vacuum requirements as these raise costs  Benefits from increases in scale of equipment, such as those that exist in chemical plants and production of liquid
    15. 15. Outline  What is nanotechnology?  Fullerene, Graphene and Carbon Nanotubes  Quantum Dots  Nanoparticles  Nanofibers  Common issues
    16. 16. Fullerenes, Graphene, and Carbon Nanotubes Fullerenes specific number of carbon atoms arranged as sphere 20 is the smallest, many other stable numbers Graphene flat sheet of carbon atoms Carbon Nanotubes flat sheet is rolled so that sides are connected, thus
    17. 17. Fullerenes As size of fullerenes increases, energy gap between highest and lowest orbital also decreases where this gap is analogous to the band gap in semiconductors One can also dope fullerenes by inserting atoms inside of them Thus, one can design fullerenes with specific electronic properties as with semiconductors Depending on purity, price of fullerenes is more than $100 per gram
    18. 18. Graphene  A single layer of carbon atoms  Very low electrical resistance, high thermal conductivity (4,000 W/m-K), and high mobility (about 200,000 cm2/Vs at room temperature, compared to 1,400 in silicon and 77,000 in indium antimonide)  One of strongest materials, but yet flexible  Unusual optical behavior: equally transparent to ultraviolet, visible and infrared light  Two current markets (composites for strength and electrodes for conductivity) but also displays, computer chips, and solar cells  http://www.youtube.com/watch?v=XDJRlBSXsow Source: Segal, Michael (2009). "Selling graphene by the ton". Nature Nanotechnology 4 (10): 612–4 Nature 483, S29 (15 March 2012). Also http://www.azom.com/news.aspx?newsID=11679
    19. 19. One Measure of Improvement  Diameter of the sheets that can be fabricated  According to Prof..Tomas Palacios of MIT, the size of graphene sheets has been increased from a few microns to about 30 inches in the last few years. Further increases will open up new applications as will cost reductions.  http://edition.cnn.com/2013/04/29/tech/graphene- miracle-material/index.html?hpt=hp_c3
    20. 20. 300 square centimeter graphene film from Graphene frontiers Graphene Frontiers claims it will have a roll-to-roll machine prototype ready within a few years. The three big applications will be desalinization and filtration, biosensing and electronics.
    21. 21. http://www.azonano.com/article.aspx?ArticleID=3185
    22. 22. But lots of controversy!!!! Many argue these large sheets do not have consisten performance (including flatness) across the sheets
    23. 23. Another Measure of Improvement is Price (Euros/cm2) http://www.graphenea.com/pages/graphene- price#.Ut8YMRAZ6Uk
    24. 24. What About Graphene Composites?  Alternate layers of graphene with other materials  grow single layer of graphene on a metallic deposited substrate using chemical vapor deposition, then add another metal layer  repeat the steps, resulting in multilayer metal-graphene composite of 0.00004% in weight of graphene  The graphene makes copper 500 times and nickel 180 times stronger  Big application for aircraft?  Another material, a nanocoating, reduced fuel consumption by 2 percent and enabled one airline to save $22 million per year http://spectrum.ieee.org/nanoclast/semiconductors/nanotechnology/for-first-time-graphene-and-metal- make-strong-composite
    25. 25. Not Just Graphene, i.e., Carbon  As of April 2013, >10 materials found that are one or a few atoms thick  Transition metal dichalcogenides for solar cells http://gizmodo.com/super-thin-graphene-solar-panels-could-pave-the-way-for-489111383  Boron nitride (insulator) has been fabricated in one- atom sheet as has Molybdenum Sulfide  Molybdenum Sulfide is semiconductor, Boron Nitride is insulator, Graphene is for interconnect  Together one atom thick flash memory devices have been constructed (http://www.thessdreview.com/daily-news/latest-buzz/flash-memory-to-be-based- on-2d-materials-a-single-atom-thick/)  More complex devices can be constructed by doping one of the layers http://thessdreview.com/daily-news/latest-buzz/flash-memory-to-be-based-on-2d-materials-a-single-atom- thick/ April 29, 2013. http://edition.cnn.com/2013/04/29/tech/graphene-miracle-material/index.html?hpt=hp_c3
    26. 26. Other Materials have Similar Hexagonal Lattice Structures to Graphene Source: Nature, Vol 497, 23 May 2013
    27. 27. Returning to Graphene, Why Might it Get Dramatically Cheaper? Material costs are obviously low…………
    28. 28. How much Cheaper will Graphene or other Ultra-thin materials become?  Will new processes be found?  Will increases in scale help?  The large number of possible processes and composites makes people optimistic  What applications will become possible as the cost of graphene falls? Source: http://www.multibriefs.com/briefs/spe/Graphene-based%20nanocomposites.pdf
    29. 29. http://iopscience.iop.org/1402-4896/2012/T146/014024/article Methods of Making Graphene Film
    30. 30. http://iopscience.iop.org/1402-4896/2012/T146/014024/article CVD-Based Graphene Growth on Ni, Cu,
    31. 31. Growing Graphene on Cu Films http://iopscience.iop.org/1402-4896/2012/T146/014024/article
    32. 32. Different Methods of Synthesis, Different Application
    33. 33. What about applications? And Market Growth?
    34. 34. A likely early application: Flexible Transparent Electrodes  Replace indium tin oxide in solar cells, light- emitting diodes (LEDs), organic light-emitting diodes (OLEDs), touch screens, smart windows LCD displays  Different levels of sheet resistance are needed for each  Composites have highest levels of conductance and transmittance (FeCl3-FLG [few layer graphene])  Problems with indium tin oxide  High deposition temperature, brittle and fragile http://iopscience.iop.org/1402-4896/2012/T146/014024/article
    35. 35. http://onlinelibrary.wiley.com/doi/10.1002/adma.201200489/abstract;jsessionid=2450 8C91658C71CB5F94C7AED94D5BC8.d03t01
    36. 36. http://iopscience.iop.org/1402-4896/2012/T146/014024/article Transparent Electrodes, continued
    37. 37. Looking Further to the Future: Graphene Aircraft?  What about making aircraft from grapheme?  Why would we want to do this?  How might we estimate the cost of making aircraft from grapheme?
    38. 38. Looking Further to the Future: Graphene Aircraft?  If graphene is 0.1 Euro/cm2(Graphena‘s estimate for 2020) would Airbus or Boeing use graphene as the material for fuselage or wings?  How would you do a rough calculation?  Roughly speaking, since a Boeing 777‘s fuselage and wings have a surface area of about 3000 square meters, it would cost about 3 million Euros for a single layer of Graphene to be used on their fuselage and wings or about 1/100 the current price of a Boeing 777. The fuselage of Boeing 777 has a length of about 80 meters and a diameter of about 6 meters
    39. 39. One Possible Future  All structures and products are made from single atom thick materials  Would lead to much lower material usage  And thus less energy needed to make materials?  Steel and other materials require lots of energy  Lower energy usage by transportation equipment  Lighter equipment leads to lower energy usage  More interesting structures  Taller structures  More interesting shapes that are not constrained by weight  Carbon fiber has been moving us in these directions for many years, but single atom thick materials can
    40. 40. Will Graphene Make these Highways Economically
    41. 41. http://nextgenlog.blogspot.sg/2012/07/materials-graphene-rising-to-1- billion.html Back to Reality, the market is still small….How fast will it grow?
    42. 42. Replacement of existing component in an existing product. Replace: carbon black, carbon fibre, graphite, carbon nanotubes, silver nanowires, Indium Tin Oxide, silver flakes, copper nanoparticles, aluminium, silicon, GaAs, ZnO, etc. The strength of graphene's value proposition is different for each target market. http://www.printedelectronicsworld.com/articles/idtechex-forecasts-a-100-million-graphene-market-in- 2018-00004721.asp?sessionid=1 IDTechEx forecasts $100 million Graphene market in 2018 (on 12 September 2012)
    43. 43. Outline  What is nanotechnology?  Fullerene, Graphene and Carbon Nanotubes  Quantum Dots  Nanoparticles  Nanofibers  Common issues
    44. 44. Single (SWNT) and Multi-Walled Nano Tube (MWTB) Carbon nanotubes can be made with single or multiple walls, in different diameters, and with different axes Like fullerenes, only certain diameters exist and each design has different properties
    45. 45. Carbon Nanotubes (1)  Diameters and axes impact on  levels of conduction and thus  whether the carbon nanotube is a conductor, semiconductor, or an insulator  Conducting nanotubes  1000 times higher conductivities than copper  100 times higher current densities than superconductors  but only if there is one continuous piece of nanotube (which is quite difficult)  Easier to make long superconductors (but even this is difficult) than long nanotubes  Thus, carbon nanotubes will probably be used for short distances, for example for IC or board level interconnect
    46. 46. Carbon Nanotubes (2)  Carbon nanotubes are the strongest materials known in terms of tension  However, lack of consistency means that these strengths may not be maintained at the macroscopic level with many nanotubes  One application is cutting thin slices of biologic material (<100 nm)  Very high levels of thermal conductivity: 5000 W/m-K  Because its characteristics (e.g., conduction, strength) vary by design (e.g., diameter) and process, much research is still trying to understand the relationship between design, process, and characteristics
    47. 47. Price is critical: Price per gram of Single Walled Carbon Nanotubes has steadily fallen (Aluminum is $2.50 per kg or 1/400, Gold is 60$/gram or about 2/3) From Nanotechnology by Ben Rogers, Sumita Pennathur, Jesse Adams, CRC Press, 2011
    48. 48. Another Source of Price Data (Multi-ton orders)Price(USD/gram) 0.000 0.001 0.010 0.100 1.000 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 SWNT (90wt%) Indium Silicon MWNT Carbon Fibre Steel Year Source: MT5009 fall semester 2013, group project
    49. 49. Environmental Assessment of Single-Walled Carbon Nanotube Processes, Journal of Industrial Ecology, Vol 12, No. 3 Meagan L. Healy, Lindsay J. Dahlben, and Jacqueline A. Isaacs Electrical Energy Requirements are One Reason for High Prices
    50. 50. Source: Minimum Exergy Requirements for the Manufacturing of Carbon Nanotubes, Timothy G. Gutowski, John Y. H. Liow, Dusan P. Sekulic, IEEE, International Symposium on Sustainable Systems and Technologies, Washington D.C., May 16-19, 2010 for Carbon Nanotubes But the Energy Requirements are Falling
    51. 51. Will Costs Fall?  Like Graphene, Carbon NanoTubes have low material costs  But how much will the processing costs fall?
    52. 52. Large Variety of Processes Makes Many Optimistic about Carbon Nanotubes  Carbon nanotubes are made by several methods  Chemical Vapor Deposition (CVD)  arc discharge  laser ablation  HIPCO®: Hi-pressure carbon monoxide  surface mediated growth of vertically-aligned tubes by Plasma Enhanced Chemical Vapor Deposition (PECVD)  Understanding their growth in these processes is critical to making them cheaper  Costs will probably fall as scale increases of HIPCO process (see later slide on nano-fibers made from carbon nanotubes)
    53. 53. Researchers at USC have solved a long-standing challenge with carbon nanotubes: how to actually build them with specific, predictable atomic structures.―We are now working on scale up the process,‖ Zhou said. ―Our method can revolutionize the field and significantly push forward the real applications of nanotube in many fields.‖ Until now, scientists were unable to ―grow‖ carbon nanotubes with specific attributes — say metallic rather than semiconducting — instead getting mixed, random batches and then sorting them. The sorting process also shortened the nanotubes significantly, making the material less practical for many applications. Chirality-Dependent Vapor-Phase Epitaxial Growth and Termination of Single-Wall Carbon Nanotubes, Bilu Liu †, Jia Liu †, Xiaomin Tu ‡, Jialu Zhang †,Ming Zheng *‡, and Chongwu Zhou *, nanoletters, Augu Improved Control over Production of CNTs
    54. 54. Electrical/Electronic Applications  Transparent Electrodes for displays, batteries and solar cells  Transistors and Interconnect for integrated circuits  Cables and Wires  Ultra-capacitors for energy storage  Sensors  Medical – vibrations of nanotubes from radio waves (pass through tissue) or their emission of light can kill cancer cells
    55. 55. For Transparent and Conductive Sheets on Electronic Paper (Trying to find lower resistance and higher transmittance) http://www.osa-direct.com/osad-news/654.html
    56. 56. Another Application Might be Flywheels  May be a large market for carbon nanotubes and/or grapheme  Energy density of flywheels is a function of strength- to weight ratio  E/m = K (sigma/rho)  E= kinetic energy of rotor; M = mass  K = rotor‘s geometric shape factor  Sigma = tensile strength of material  Rho = material‘s density  Flywheels have about same energy density as Li-ion batteries but much faster rate of improvement  Carbon fibers are now being used in formula 1 cars  But CNTs have 10 times higher strength to weight ratios than do carbon fiber. Thus 10 times higher energy densities are possible Source: Presentation by MT5009 students on April 11, 2013. Slides can be found on http://www.slideshare.net/Fun
    57. 57. For Transistors and Integrated Circuits  I.B.M. scientists were able to pattern an array of carbon nanotubes on the surface of a silicon wafer and use them to build hybrid chips with more than 10,000 working transistors  They did this by using a process they described as ―chemical self-assembly‖ to create patterned arrays in which nanotubes stick in some areas of the surface while leaving other areas untouched  Perfecting the process will require a more highly purified form of the carbon nanotube material http://bits.blogs.nytimes.com/2012/10/28/i-b-m-reports-nanotube-chip-breakthrough/
    58. 58. Improvements in Purity of CNTs (and Increases in Source: Electronics: The road to carbon nanotube transistors, Aaron D. Franklin Nature 498, 443–444 (27 June 2013)
    59. 59. For Transistors and Integrated Circuits (2)  In the short term, high purity CNTs will probably be used to achieve higher conductivity channel length and perhaps interconnect  Mentioned in previous session  In the long run, different types of CNTs may be used for the conducting, insulating, and semiconducting regions  Thus creating a new form of integrated circuit http://bits.blogs.nytimes.com/2012/10/28/i-b-m-reports-nanotube-chip-breakthrough/
    60. 60. Market Size for Carbon Nanotubes
    61. 61. Production Capacity, Producers, and Applications for Carbon NanoTubes http://www.nanowerk.com/spotlight/spotid=23118.ph p
    62. 62. Outline  What is nanotechnology?  Fullerene, Graphene and Carbon Nanotubes  Quantum Dots  Nanoparticles  Nanofibers  Common issues
    63. 63. Quantum Dots  Semiconductors also exhibit interesting behavior as sizes reach the nano-scale, single nanometer levels  Quantum dot is semiconductor whose electronic characteristics are closely related to size and shape of individual crystal  Generally, the smaller the size of crystal, the larger the band gap and thus  the greater the difference in energy between the highest and lowest conduction band becomes  therefore more energy is needed to excite the dot, and concurrently, more energy is released when the crystal returns to its resting state
    64. 64. Quantum Dots (2)  For example, some can emit light like a laser  Size of the dot determines the wavelength, i.e., color of the light, that is emitted  Power consumption is very low  Efficiency and switching speeds can be very high  While others can absorb light  Size of the dot determines the wavelength, i.e., color of the light, that is absorbed (i.e., solar cells)  One problem is that they are very expensive (thousands of dollars per gram)
    65. 65. Source: Semiconductor II-VI Quantum Dots with Interface States and Their Biomedical Applications By Tetyana Torchynska and Yuri Vorobiev Different Size Dots Emit Different Wavelengths of Light
    66. 66. Applications of Quantum Dots  Lasers and Displays  Different size dots on a single substrate each emitting different wavelengths with lower power consumption  Lasers can be smaller, faster, and consume less power than current ones for telecommunication and computing applications  Solar cells/Photosensors  different size quantum dots absorb different wavelengths of light  Thus a single substrate can absorb different wavelengths of light and thus have much higher efficiencies than current solar cells  Higher sensitivities for photosensors  Medical applications  Different dots are coated with different layers, which enable different dots to bond with different targets
    67. 67. http://www.photonics.com/Article.aspx?AID=14668 Quantum Well and Dot-Based Lasers
    68. 68. Materials Today 14(9) September 2011, Pages 388–397 Reductions in Threshold Current, i.e., Minimum Current Needed for Lasing to Occur (by reducing sizes of devices)
    69. 69. Source: Changhee Lee, Seoul National University http://www.andrew.cmu.edu/org/nanotechnology-forum/Forum_7/Presentation/CH_Lee.pdf JH Kwak PhD Thesis (2010) Improvements in Efficiency of Quantum Dots for Dis
    70. 70. Manufacturing is One Challenge  These dots can be manufactured by depositing a vapor of the relevant compound, e.g., molecular beam epitaxy  For example, the atomic lattice mismatch between InAs and GaAs causes the deposition of InAs onto GaAs where the InAs self-assembles into nanoscale islands that show quantum dot behavior  Quantum dots are much more expensive than quantum wells  Can costs be reduced? By how much?  As the costs/prices are reduced, what kinds of applications become economically feasible?http://www.photonics.com/Article.aspx?AID=14668
    71. 71. Is the Market for Quantum Dots Growing A key barrier is price: quantum dots can cost anywhere from US$3,000 to $10,000 per gram, restricting their use to highly specialized applicationsSource: http://www.nature.com/news/ 2009/090610/full/459760a.ht ml (2009)
    72. 72. Source: http://bccresearch.blogspot.sg/2012/09/global-market-for-quantum-dots-to-grow Market for Quantum Dots, Forecasted in Septemb
    73. 73. Outline  What is nanotechnology?  Fullerene, Graphene and Carbon Nanotubes  Quantum Dots  Nanoparticles  Nanofibers  Common issues
    74. 74. Characteristics of NanoParticles  Greater percentage of atoms at surface, which leads to unique properties  Changes in wavelengths absorbed and emitted  Higher reactance  Higher magnetic moment  Higher strength  Ability to enter living organisms  But finding the appropriate material and matching it to the application is a major challenge
    75. 75. Source: Binns, C. 2010. Introduction to Nanoscience and Nanotechnology
    76. 76. Absorption Varies by Size of Nanoparticle  Like quantum dots, absorbed wavelengths vary by size  For example, small particles of zinc oxide and titanium dioxide absorb ultraviolet but not visible light  Thus, the sunscreen is invisible to visible light
    77. 77. Reactanc e increases as Size decrease s; How much more can be achieved ?
    78. 78. High Reactivity is Useful for some Applications  Can be used for stain resistant pants  Small particles react with stains to eliminate them  How about other applications?  Can other materials be found whose reactance varies by size?  Will these new materials lead to applications other than stain resistant pants?  Or maybe just help in existing applications. For example, high reactance can lead to
    79. 79. Source: Binns, C. 2010. Introduction to Nanoscience and Nanotechnology Magnetic moments increase as particle size decreases; how much more can be achieved? Rh
    80. 80. Magnetic Nanoparticles  Can make single particle magnetic storage possible  Increases limit of platters to 100 Tb/in2, or 1000 times more than existing densities  But medical applications may be bigger  Aids in detection by improving contrast of MRI via higher magnetic moments; improvements are possible  Can be steered to cancer cells with external magnetic field  Can destroy cells by oscillating magnetic field that creates heat  Trials on humans have started
    81. 81. Improved Relaxivity (better detection) with Higher Magnet Moments (Dotted line shows expected improvements Source: Binns, C. 2010. Introduction to Nanoscience and Nanotechnology
    82. 82. Source: Binns, C. 2010. Introduction to Nanoscience and Nanotechnology Cancer cells can be killed by Hyperthemia
    83. 83. Hyperthemia  Power of about 0.1 W/cm3 is needed to kill cancer cells  Effectiveness of nanoparticles at heating can be measured by specific absorption rate (SAR)  Typical rate for magnetic nanoparticles is 10 W/g  Thus  0.01 g of nanoparticle is required to achieve 0.1 W and  Thus hundreds of thousands of nanoparticles are needed for cancer cells, which is probably far more than is possible for many receptors
    84. 84. Are These Values for SAR Sufficient?
    85. 85. Other Treatments for Killing Cancer Cells  Current treatments (e.g., chemotherapy) kill patients  Nanoparticles can be ―programmed/designed‖ to find and kill specific cancer cells  Several thousand have been reported in literature  Lipsomes, protocells release drugs on contact with cancer cells  Dendrimers are tree-like polymers with many active sites for bonding external agents – each targeting cancer cells  Reflectivity of light from gold and silver particles depends on their binding to cancer cells and some of them can be made to vibrate and kill cancer cells via absorption of infrared light  Vibrations of nanotubes from radio waves (pass through tissue) or their emission of light can kill cancer cells
    86. 86. Part of Finding Cancer Cells Involves Biological Targeting  Selective binding to cancer cells enhances treatment  Antibodies are the oldest and most studied  but too large (can‘t enter cells) and expensive  Nanobodies contain fragments of antibodies  Aptamers  artificially short section of DNA  much cheaper than antibodies  Peptides are even smaller  Composed of 20 amino acid building blocks  Smallest method of targeting is folates/folic acid: only 51 atoms  Finding the appropriate biological material and
    87. 87. Big Challenge is Price  Nanoparticles are made by condensation of a supersaturated vapor into particles particularly with a vacuum source  But since the cost of a vacuum is high, many search for a cheaper process such as one using high voltage sparks  Since magnetic nanoparticles are often used for living organisms and are produced by some bacteria, some use bacteria to synthesize them.  On the other hand, only a small number of particles may be needed for each patient…
    88. 88. Outline  What is nanotechnology?  Fullerene, Graphene and Carbon Nanotubes  Quantum Dots  Nanoparticles  Nanofibers  Common issues
    89. 89. Examples  Cargo nets  Ultra-high-molecular-weight polyethylene  15 times stronger on a weight basis than steel, but 4 times more expensive than typical polyester net  Robotic cables  Vectran  Fire resistant textiles  Textiles that  absorb body odor  block radiation
    90. 90. Smaller Diameters Lead to Higher Strength  This is true for many materials such as electrospun Polyamide 6.6 fibers  The increased strength of fine diameter fibers (<500 nm) is attributed to the oriented fragments of amorphous chains  The fibers display remarkably improved properties when the size of this oriented amorphous part is comparable to overall fiber diameter  But finding the appropriate materials and applications for them is a challenge
    91. 91. Decreasing the size of the fiber leads to higher tensile strength (breaking point) and tensile modulus (tension) (Hi-Tensile Steel is 1860 and 200) Source: Effect of fiber diameter on the deformation behavior of self- assembled carbon nanotube reinforced electrospun Polyamide 6,6 fibers Avinash Baji, Yiu-Wing Maia, Shing-Chung Wong. Materials Science and Engineering A 528 (2011) 6565– 6572
    92. 92. Big Challenge is Manufacturing/Process  Electrospinning is the main manufacturing technique, but still quite expensive  Improvements over the last ten years in productivity of single nozzle setup from 0.5 grams per hour to 6.5 kilograms per hour (Source: Chem. Soc. Rev., 2012, 41, 4708– 4735)  To what extent can further improvements be made?  What applications will be made possible through these reductions in cost/price?
    93. 93. What About Using Carbon NanoTubes to Make these Fibers?  Since they have nano-level dimensions, we would expect the fibers made from them to have high strength  Manufacturing techniques:  spinning from a lyotropic liquid crystalline suspension of nanotubes, in a wet-spinning process similar to that used for polymeric fibers such as aramids  spinning directly from an aerogel of single walled carbon nanotube (SWCNTs) and multi-walled CNTs (MWCNTs) as they are formed in a chemical vapor deposition reactor  spinning from MWCNTs previously grown on a substrate as ‗‗semialigned‖
    94. 94. Carbon NanoTube (CNT)-based fibers can have Higher strengths than do other High- performance fibers Source: An assessment of the science and technology of carbon nanotube- based fibers and composites, Tsu-Wei Chou b,*, Limin Gao a, Erik T. Thostenson b, Zuoguang
    95. 95. The Main Challenge is Process/Manufacturing  Strength, other performance dimensions and cost depends on process so need improvements in process  Cost data could not be found but…  Energy requirements are still high  Four orders of magnitude less than that of carbon nanotubes  Similar energy per kg as Aluminum  But carbon nanotubes must be made before the fiber can be made…….
    96. 96. Source: Minimum Exergy Requirements for the Manufacturing of Carbon Nanotubes, Timothy G. Gutowski, John Y. H. Liow, Dusan P. Sekulic, IEEE, International Symposium on Sustainable Systems and Technologies, Washington D.C., May 16-19, 2010 Energy Intensity vs. Process Rate for Production of Carbon Nano-fibers to put these process rates in perspective, ethylene is made in factories one million times larger than this
    97. 97. Market forecasted to grow from US$ 140M in 2010 to US$ 4B by 2020 http://www.adsaleata.com/Publicity/MarketNews/lang- eng/article-112763/Article.aspx
    98. 98. Outline  What is nanotechnology?  Fullerene, Graphene and Carbon Nanotubes  Quantum Dots  Nanoparticles  Nanofibers  Common issues
    99. 99. Common Issues (1)  Need to find materials that better exploit small dimensions and that are appropriate for specific application  Nanoparticles that selectively bind to cancer cells and kill them  Materials for quantum dots and nanofibers  Need to find new processes that produce more appropriate and better nano-materials  But at what rate and for what applications are we finding these new materials?  And what does this tell us about when new applications become economically feasible?
    100. 100. Common Issues (2)  Costs are too high  Nanoparticles, Quantum Dots, Nanofibers  Fullerene, Graphene and Carbon Nanotubes  How fast will costs fall?  They will probably fall at slower rate than what has been seen with ICs (i.e., Moore‘s Law)  No discernible benefit from reductions in scale  Costs may fall as scale of production is increased or as new processing methods are found  See Sessions 2 and session on roll-to roll printing for more details on impact of increases in scale of production equipment on manufacturing costs  Which applications will become economically feasible as the production costs for nanotechnology fall?
    101. 101.  Appendix
    102. 102. Price of carbon fiber http://www.zoltek.com/carbonfiber/the-history-of-carbon-fiber/ Carbon fiber in vehicles http://auto.howstuffworks.com/fuel-efficiency/fuel-economy/carbon-fiber-oil-crisis2.htm Roadmap for graphene http://www.nature.com/nature/journal/v490/n7419/full/nature11458.html?WT.ec_id=NATURE- 20121011 http://www.graphenea.com/pages/graphene-price#.UonUjnASbTp Euros per square
    103. 103. Graphene transistors http://phys.org/news/2012-07-graphene-transistor.html Improve strength of material by combining it with graphene in sandwich composite http://spectrum.ieee.org/nanoclast/semiconductors/nanotechnology/for-first-time- graphene-and-metal-make-strong-composite Graphene applications http://www.graphenea.com/pages/graphene-uses-applications#.UonTB3ASbTr http://www.ft.com/cms/s/0/6f4717b6-66f9-11e2-a83f- 00144feab49a.html#axzz2ktOs2EWw Transparent conductors http://onlinelibrary.wiley.com/doi/10.1002/adma.201200489/abstract;jsessionid=245 08C91658C71CB5F94C7AED94D5BC8.d03t01 http://www.luxresearchinc.com/blog/coveragearea/advanced-materials/

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