Nanotechnology

1. Nanotechnology Science, Technology and Public Affairs PAF 547 S. Tom Picraux Dept. of Chemical and Materials Engineering Fulton School of Engineering picraux@asu.edu Arizona State University

2. This presentation has 2 objectives: • Overview the scientific basis of nanotechnology • Highlight the government’s role and current public policy issues in nanotechnology

3. Nanotechnology:a definition — working with matter down to the molecular level to create structures and devices ~1 to 100 nm in size with fundamentally new organization, properties, and performance • takes us to the realm where the properties of materials are dramatically different. • demands new tools and new understanding. • may hold the key to a 21st century industrial revolution.

4. What are the key challenges of nanoscale science and technology? Making nanomaterials Self assembly, top down vs. bottom up Characterizing nanostructures Imaging and measuring small things Understanding properties “Nanoland” lies between macro world and single atoms and molecules Nanosystemsintegration & performance - How do we assemble nanostructures into systems (this is the high payoff area)

5. Self-Assembly: Nature’s approach to nanotechnology • Living Cell Walls • “fluid” molecular arrays rearrange in response to chemical stimuli • changes in membrane structure influence intercellular diffusion • Photosynthesis centers • optical receptor molecules are precisely aligned via spontaneous organization • alignment promotes collection, storage, and utilization of light energy 3D molecular arrangements promote resonant coupling. Dynamic restructuring of molecular arrays provides adaptive response.

6. How to build things at the nanoscale? Conventional Machines Build and assemble Microelectronics Top down - build in place (m - mm) Nanotechnology Bottom up - self assembled (10 - 0.1 µm) (1- 100 nm)

7. The Scale of Things – Nanometers and More Ant ~ 5 mm Dust mite 200 mm Fly ash ~ 10-20 mm Things Natural Things Manmade 1 cm 10 mm 10-2 m Head of a pin 1-2 mm The Challenge 1,000,000 nanometers = 10-3 m 1 millimeter (mm) MicroElectroMechanical (MEMS) devices 10 -100 mm wide Microwave 0.1 mm 100 mm 10-4 m Human hair ~ 50-120 mm wide Microworld 0.01 mm 10 mm 10-5 m Pollen grain Red blood cells Infrared Red blood cells with white cell ~ 2-5 mm Zone plate x-ray “lens”Outer ring spacing ~35 nm 1,000 nanometers = 10-6 m 1 micrometer (mm) Visible Fabricate and combine nanoscale building blocks to make useful devices, e.g., a photosynthetic reaction center with integral semiconductor storage. 0.1 mm 100 nm 10-7 m Ultraviolet Self-assembled, Nature-inspired structureMany 10s of nm Nanoworld 0.01 mm 10 nm 10-8 m ~10 nm diameter Nanotube electrode ATP synthase 10-9 m 1 nanometer (nm) Carbon buckyball ~1 nm diameter Soft x-ray Carbon nanotube ~1.3 nm diameter DNA ~2-1/2 nm diameter 10-10 m 0.1 nm Quantum corral of 48 iron atoms on copper surface positioned one at a time with an STM tip Corral diameter 14 nm Atoms of silicon spacing ~tenths of nm Office of Basic Energy Sciences Office of Science, U.S. DOE

8. 2-nm Al2O3 particles Nanomaterials: new physics and chemistry revolutionizes materials performance Single molecule sensing New phenomena associated with: • Small size (e.g. quantized effects) • Preponderance of surfaces and interfaces Lead to: GPa strength from Ni • New modes of electronic transport • Radical changes in collective phenomena • New chemical reactivities • New mechanical properties Practicing “alchemy” through structure

9. Carbon Nanotubes: example of extreme properties The scale of nanostructures Top down (~200 nm) Bottom up (~1 nm) armchair zig-zag Nanotubes for Electronics, Scientific American, Dec. 2000

10. Why are nanomaterials attractive? Information technology Quantum electronics (logic, memory), magnetic memory, spintronics Energy Large scale, low cost nanoparticle-based solar energy collection High efficiency solid state lighting Health In situ drug delivery Diagnostics, active monitoring, performance enhancement Environment Low cost, nanosensor arrays for health, safety Nanoparticle based waste destruction Nanomanufacturing Large area, bottom up assembly for low waste, energy efficient manufacturing

11. Practical applications are at an early stage The Top Ten Nanotech Products Of 2003 Robert Paull, The Forbes/Wolfe Nanotech Report, 12/29/03 1) High-Performance Ski Wax 2) Breathable Waterproof Ski Jacket 3) Wrinkle-Resistant, Stain-Repellent Threads 4) Deep-Penetrating Skin Cream 5) World's First OLED Digital Camera 6) Nanotech DVD and Book Collection 7) Performance Sunglasses 8) Nanocrystalline Sunscreen 9 & 10) High-Tech Tennis Rackets And Balls It has been estimated that nanostructured materials and processes can be expected to have a market impact of over $340 billion within a decade (Hitachi Research Institute, 2001).

12. Public visibility is growing Washington Post, Sunday, Feb. 22, 2004

13. Nanotechnology and Society • Are paradigm shifting consequences of nanotechnology likely to occur? • Are there areas where broad societal debate needs to be carried out concurrent with research? • What is the role of government? • What are the responsibilities of scientists and engineers?

14. Governments play a significant role in the development of Nanotech National Nanotechnology Initiative U.S. Funding Total NNI Funding ($M) Pre-program FY01 funding Fiscal Year Worldwide nanotech funding ~$3.5B in FY03: (Europe, Japan, US, Korea, Singapore, Taiwan, China, …)

15. Nanotechnology cuts across a wide area of society FY04 Funding by Agency NNI Funding ($M) U.S. Government Agency

16. The enormous U.S. investment in nanotechnology is predicated on economic competitiveness and societal impact NNI Program Grand Challenges • Nanostructured materials by design • Manufacturing at the nanoscale • Chemical-biological-radiological-explosive detection • Nanoscale instrumentation and metrology • Nano-electronics, photonics, and magnetics • Healthcare, therapeutics and diagnostics • Efficient energy conversion and storage • Microcraft and robotics • Nanoscale processes for environmental improvement

17. Governments respond to societal priorities and concerns National Nanotechnology Bill S189 signed Dec. 3, 2003 • An authorization bill • Follows the NNI program directions • Emphasizes program: • management • coordination • review/oversight • and ethical, legal, environmental and societal concerns!

18. Specific societal-driven inclusions in the S189 Bill • The National Nanotechnology Bill creates: • American Nanotechnology Preparedness Center 1) “conduct, coordinate, collect, and disseminate studies on the societal, ethical, environmental, educational, legal and workforce implications of nanotechnology” 2) “identify anticipated issues related to the responsible research, development, and application of nanotechnology, as well as provide recommendations for preventing or addressing such issues” • Center for Nanomaterials Manufacturing • encourage, conduct, …. research on new manufacturing technologies for materials, devices, and systems … • Develop mechanisms to transfer such manufacturing technologies to U.S. industries

19. Nanotechnology and Society: • Nanoparticles – Potential Health Risks • Properties change with size. • Can some sizes + compositions have adverse health effects? • Implications for gov’t regulatory system. Same chemical, different forms: e.g., carbon black, diamond, buckyball, nanotube Same chemical, different size: e.g. TiO2, quantum dots (CdS, CdSe) • Can nanoscale particles cross biological barriers? • What are our responsibilities and precautions? • in the lab? • in the factory or the environment? • in consumer products?

20. Nanoscale Materials Categorizations Naturally occurring “ultrafine particles” • Virus – 10 to 60 nm • Bacteria – 30 to 10 µm • Dust from deserts - ~ 100 nm • Volcanic ash, Forest fire smoke “Ultrafine particles” from established technologies or by products of conventional Processes • Combustion soot – 10 to 80 nm • Paint pigments – 80 to 100 nm • Welding fumes – 10 to 50 nm • Diesel exhaust particles – (Small mode) 7 to 40 nm • Carbon black for photocopier toner – 10 to 400 nm Engineered nanoscale materials – “nanomaterials” • Fullerenes – buckyballs – 1 nm: nanotubes – 1 to 5 nm x 10 µm • Quantum dots for medical diagnosis– 5 to 20 nm • Semiconductor wires for sensors – 10 to 100 nm diam. x 1 µm NNI Clayton Teague presentation, 4/2/04

21. Some Initial Health Studies of Nanoparticles • Lam et al. (2004) – washed 3 kinds of carbon nanotubes into lungs of mice; all caused lung granulomas • Dupont injected nanotubes into rat lungs; 15% died (highest death rate seen in such studies) • SMU – buckyballs cause extensive brain damage in fish • Rice University – studies show nanoparticles bioaccumulate in living tissues

22. Specific Federal Projects on Implications NIH/ NIEHS – support of the new National Toxicology Program, ~$3M multi-year project initiated in FY2004 • Studies to evaluate the toxic and carcinogenic potential of test agents (quantum dots, nanotubes) in laboratory animals via inhalation exposure EPA – Impacts of manufactured nanomaterials on human health and the environment, $4M in FY2004 • Toxicology of manufactured nanomaterials • Fate, transport, and tranformation of manuf. Nanomaterials • Human exposure and bioavailability NNI Clayton Teague presentation, 4/2/04

23. Nanotechnology and Society: Public Debate (continued) • Ubiquitous Nanosensors – Privacy of the individual • What if the walls have eyes and ears? • What if sensors can be attached to me without my knowledge? • Is my health and genetic susceptibilities private information?

24. Nanotechnology and Society: Public Debate (continued) • “Bots” – Self replicating nanomachines • Is it feasible? • What previous experience can we draw upon? • Is responsible action needed?

25. Nanotechnology and Society: Public Debate (continued) • “NanoAssistors” – Human-machine interfaces • Are human assistive devices for the disabled appropriate nanotechnology to support? • Should nanotechnology be used to enhance human performance? • for warfighters? • for athletes? • for my children? • Who decides?