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

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

— 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 Nanotechnology: a definition 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.

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 Nanosystems integration & performance - How do we assemble nanostructures into systems (this is the high payoff area)

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

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

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

Nanomaterials: new physics and chemistry revolutionizes materials performance Lead to: GPa strength from Ni New phenomena associated with: Small size (e.g. quantized effects) Preponderance of surfaces and interfaces New modes of electronic transport Radical changes in collective phenomena New chemical reactivities New mechanical properties 2-nm Al 2 O 3 particles Single molecule sensing Practicing “alchemy” through structure

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

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 Why are nanomaterials attractive?

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).

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

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?

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

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

NNI Program Grand Challenges 1.Nanostructured materials by design 2.Manufacturing at the nanoscale 3.Chemical-biological-radiological-explosive detection 4.Nanoscale instrumentation and metrology 5.Nano-electronics, photonics, and magnetics 6.Healthcare, therapeutics and diagnostics 7.Efficient energy conversion and storage 8.Microcraft and robotics 9.Nanoscale processes for environmental improvement The enormous U.S. investment in nanotechnology is predicated on economic competitiveness and societal impact

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

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 1)encourage, conduct, …. research on new manufacturing technologies for materials, devices, and systems … 2)Develop mechanisms to transfer such manufacturing technologies to U.S. industries Specific societal-driven inclusions in the S189 Bill

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. TiO 2, 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?

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

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

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

Nanotechnology and Society: Public Debate 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? (continued)

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

Nanotechnology and Society: Public Debate “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? (continued)