NANO-TECHNOLOGY

1. NANO-TECHNOLOGY BY k.venkatesh

2. ? ? ? ? ? ? ? How do electronics keep getting smaller? ? How do stain resistant material work? The Answer: Nanotechnology makes it Possible!! ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? Is it possible for cancer patients not to have side effects? ? ? ? ? ?

3. Definition of “Nano”: One billionth (10x-9) Nanometer (nm) = one billionth of a meter Scientific Terms: A human hair is 10,000 nm wide WHAT DO YOU MEAN BY NANO

4. A field of applied science focused on design, formation, identification and application of materials and devices on the nanoscale. Definition “Nanotechnology”:

5. Vs. Two Methods of Making Nanoparticles “Top Down” Cut object smaller and smaller until attain size needed. “Bottom Up” Add atoms together one by one to attain correct property.

6. Health risks and environmental issues • Molecular manufacturing allows the cheap creation of incredibly powerful devices and products. • How many of these products will we want? What environmental damage will they do? • The range of possible damage is vast, from personal low-flying supersonic aircraft injuring large numbers of animals to collection of solar energy on a sufficiently large scale to modify the planet's equilibrium and directly affect the environment. Stronger materials will allow the creation of much larger machines, capable of excavating or otherwise destroying large areas of the planet at a greatly accelerated pace. Page-1

7. Health risks and environmental issues • ROS and free radical production is one of the primary mechanisms of nanoparticle toxicity; it may result in oxidative stress, inflammation, and consequent damage to proteins, membranes and DNA .The extremely small size of nanomaterials also means that they are much more readily taken up by the human body than larger sized particles. • Once in the blood stream, nanomaterials can be transported around the body and are taken up by organs and tissues including the brain, heart, liver, kidneys, bone marrow and nervous system • Other properties of nanomaterials that influence toxicity include: chemical composition, shape, surface structure, surface charge, aggregation and solubility , and the presence or absence of functional groups of other chemicals . (reactive oxygen species ) Page-2

8. Does Nanotechnology Address Teaching Standards?

9. Does Nanotechnology Address Teaching Standards?

10. Future uses and possibilities for Nanotechnology are endless!!! Imagine a soldier that has a uniform that can change from desert, to winter, to forest camouflage by using current from a small battery to rearrange alignment of the molecules!

11. An Example of a Nanotechnology Experiment, Which Addresses the Standards: Constructing Nanocrystalline Solar Cells Using the Dye Extracted From Citrus • Four main parts: • Nanolayer • Dye • Electrolyte • 2 electrodes

12. Nanocrystalline Solar Cells: The Materials • Materials: • (2) F-SnO2glass slides • Iodine and Potassium Iodide • Mortar/Pestle • Air Gun • Surfactant (Triton X 100 or Detergent) • Colloidal Titanium Dioxide Powder • Nitric Acid • Blackberries, raspberries, green citrus leaves etc. • Masking Tape • Tweezers • Filter paper • Binder Clips • Various glassware • Multi-meter

13. Main component: Fluorine doped tin oxide conductive glass slides Nanocrystalline Solar Cells Test the slide with a multimeter to determine which side is conductive

14. Synthesis of the Nanotitanium Suspension • Add 9 ml (in 1 ml increments) of nitric or acetic acid (ph3-4) to six grams of titanium dioxide in a mortar and pestle. • Grinding for 30 minutes will produce a lump free paste. • 1 drop of a surfactant is then added ( triton X 100 or dish washing detergent). • Suspension is then stored and allow to equilibrate for 15 minutes. Procedure

15. Coating the Cell • After testing to determine which side is conductive, one of the glass slides is then masked off 1-2 mm on THREE sides with masking tape. This is to form a mold. • A couple of drops of the titanium dioxide suspension is then added and distributed across the area of the mold with a glass rod. • The slide is then set aside to dry for one minute.

16. Calcination of the Solar Cells • After the first slide has dried the tape can be removed. • The titanium dioxide layer needs to be heat sintered and this can be done by using a hot air gun that can reach a temperature of at least 450 degrees Celsius. • This heating process should last 30 minutes.

17. Dye Preparation • Crush 5-6 fresh berries in a mortar and pestle with 2-ml of de-ionized water. • The dye is then filter through tissue or a coffee filter and collected. • As an optional method, the dye can be purified by crushing only 2-3 berries and adding 10-ml of methanol/acetic acid/water (25:4:21 by volume)

18. Dye Absorption and Coating the Counter Electrode • Allow the heat sintered slide to cool to room temperature. • Once the slide has cooled, place the slide face down in the filtered dye and allow the dye to be absorbed for 5 or more minutes. • While the first slide is soaking, determine which side of the second slide is conducting. • Place the second slide over an open flame and move back and forth. • This will coat the second slide with a carbon catalyst layer

19. Assembling the Solar Cell • After the first slide had absorbed the dye, it is quickly rinsed with ethanol to remove any water. It is then blotted dry with tissue paper. • Quickly, the two slides are placed in an offset manner together so that the layers are touching. • Binder clips can be used to keep the two slides together. • One drop of a liquid iodide/iodine solution is then added between the slides. Capillary action will stain the entire inside of the slides

20. Nanotechnology for the Environment

21. Nanotechnology and the Environment “The emerging fields of nanoscience and nanoengineering are leading to unprecedented understanding and control over the fundamental building blocks of all physical things. This is likely to change the way almost everything - from vaccines to computers to automobile tires to objects not yet imagined - is designed and made.” - Interagency Working Group on Nanoscience, Engineering, and Technology Report (1999) The bad… • Nature of nanoparticles themselves. • Characteristics of the products made. • Manufacturing processes involved. • As nano-xyz is manufactured, what materials are used? • What waste is produced? • Are toxic substances used in the manufacturing of nano-xyz? • What happens when nano-xyz gets into the air, soil, water, or biota?

22. Avoiding the Negative Cadmium sulfide (CdS) “Quantum dots” Are there more caringgentle precursor materials or synthetic methods that can be used to make the quantum dots? H2S gas CdS Enter the environment CdS + CdS CdS Cd(CH3)2 CdS Will it be possible to recover the quantum dots for reuse? Bio/Enviro/other applications Are there measures that can be taken now to minimize or avoid the negative impact quantum dots (or other nanotechnologies) may have on the environment? How are these semiconductor nanoparticles gently introduced to their target?

23. Nanotechnology and the Environment “As EPA looks to the future, it will need to employ innovative approaches and sound science to investigate complex, interdisciplinary problems in environmental protection.” - EPA FY 2001 Annual Report The good… • Nanotechnology has the potential to substantially benefit environmental quality and sustainability through • Pollution prevention • Treatment • Remediation • Information

24. Nanotechnology for pollution prevention • Synthetic or manufacturing processes which can occur at ambient temperature and pressure. • Use of non-toxic catalysts with minimal production of resultant pollutants. • Use of aqueous-based reactions. • Involved in making a manufacturing process environmentally caring • An environmentally caring material or manufactured product that replaces toxic substances or minimizes raw materials. • Build molecules as needed --“just in time.” • Nanoscale information technologies for product identification and tracking to manage recycling, remanufacture, and end of life disposal of solvents.

25. 5mm Biomolecular nanolithography • Biomimetic methods of organizing metal particles 1.5 nanometers in diameter. • Assembling the particles on a biopolymer template or scaffold stretched out on a surface. • Nanostructures are organized into well-defined chip architectures, such as lines and grids. • Process eliminates the current process chemicals that are harmful to the environment. • Nanoscale assemblies have been made that demonstrate stable, room-temperature electrical behavior that may be tolerant of defects and useful in building nanoscale circuits.

26. Treatment & Remediation • Iron Treatment Walls… • Used in groundwater treatment for many years. • Iron chemically reduces organic and inorganic environmental contaminants. • Currently involves granular or “microscale” iron ( 50 mm or 50,000 nm). End-of-pipe management and cleanup of pollution • and Nanotechnology • Nanosized iron enhances the reaction. Enhanced further by coupling with other metals (Fe/Pd)* on the nanoscale. • Nano Fe0 is more reactive and effective than the microscale. • Smaller size makes it more flexible -- penetrates difficult to access areas.

27. “Sense and Shoot” Approach to Pollution Treatment • Nanosized zinc oxide (ZnO) “senses” organic pollutants indicated by change in visible emission signal. Dual role of ZnO semicondouctor film as a sensor and photocatalyst • The ZnO “shoots” the pollutants via photocatalytic oxidation to form more environmentally caring compounds. >300 nm • Sensing capability means that the energy-consuming oxidation stage only occurs when the pollutants present. UV • Multifunctionality and “smartness” is highly desirable for environmental applications.

28. Sensors Single Molecule Detection • Molecules adsorb on surface of micro cantilever, causes a change in surface stress, cantilever bends. • Used to detect chemicals using either a specific reaction between analyte and sensor layer or chem/physisorption processes. • Applications to bio-toxins as well. Used for • Process control, compliance and ecosystem monitoring, and data/information interfaces. Need to be • Low cost, rapid, precise, and ultra sensitive. • Operated remotely and continuously, in laboratories, andin real time.

29. Conclusions Science and Engineering approaches are needed that offer new capabilities to prevent or treat highly toxic or persistent pollutants, and that result in the more effective monitoring of pollutants or their impact in ways not currently possible. Nanoscience, engineering, and technology holds great potential for the continued improvement of technologies for environmental protection. The recent breakthroughs in creating nanocircuitry, give further evidence and support the predictions that nanoscale science and engineering “will most likely produce the breakthroughs of tomorrow.” BUT the environmental implications (nano in the environment) need to be considered as we consider nano for the environment.

30. The Coming Nanotechnology Revolution • Not just new products — a new means of production • Manufacturing systems that make more manufacturing systems — exponential proliferation • Accelerated product improvement — cheap rapid prototyping • Affects all industries— general-purpose technology • Inexpensive raw materials, potentially negligible capital cost — economic discontinuity • Portable, desktop-size factories — social disruption • Impacts will cross borders — global transformation

31. Current research Space-filling model of the nanocar on a surface, using fullerenes as wheels. Graphical representation of a rotaxane, useful as a molecular switch.

32. Current research This device transfers energy from nano-thin layers of quantum wells to nanocrystals above them, causing the nanocrystals to emit visible light

33. Who defines what is nanotechnology? • Scientists • Eric K. Drexler. Engines of Creation, 1986 • Richard Smalley. “Of Chemistry, Love, and Nanobots” Scientific American, September 2001 • Political Leaders • H.R. 766 ; 108th Congress, 1st session (2003)  ” To provide for a National Nanotechnology Research and Development Program , and for other purposes” • Media • Feder, Barnaby. “Technology: a look at the dark side” New York Times May 17, 2006 • Standards-setting Organizations • American National Standards Institute “ANSI-NSP priority recommendations related to nanotechnology standardization needs” November 14, 2004.

34. Audience of the NEB • Scientists • Engineers • Business leaders • Policy makers • Scholars & Researchers • Students • General Public • All stakeholders

35. BIG STEPS in Economic, Social, and Political History Computers Automobiles Change Railways Steam Engines Time

36. BIG STEPS in Economic, Social, and Political History Change Time

37. Not Steps,butS-Shaped Curves Change Time

38. Not Steps,butS-Shaped Curves Change Time

39. Not Steps,butS-Shaped Curves Change Time

40. IndustrialRevolutions Societal Impacts Time

41. IndustrialRevolutions Societal Impacts Time (Measured in decades)

42. Nanotechnology Revolution Societal Impacts Time (Measured in YEARS)

43. AcceleratedImpacts Molecular Manufacturing Revolution Societal Impacts Industrial Revolutions Time

44. The Next Big Step Computers Societal Impacts Automobiles Railways Steam Engines (Middle Ages) Time

45. The Next Big Step Nanotechnology Computers Societal Impacts Automobiles Railways Steam Engines (Middle Ages) Time

46. The Next Big Step Nanotechnology Computers Societal Impacts Automobiles Railways Steam Engines (Middle Ages) Time

47. Once we have gained perspective, we can begin to make wise decisions for a better and safer nano future!

48. As for nanotechnology’s transformative and disruptive impacts, we’re on the roller coaster heading toward the big climb. Progress is occurring every day, taking us closer, even if we don’t notice the gradual incline. Soon, however, the curve will sharpen and take us rapidly into a future for which we may not be prepared.

49. SOME RELATED LINKS The American Heritage Sci-Tech Encyclopedia Wikipedia Intelligence Encyclopedia Britannica Concise Encyclopedia. Hacker Slang Modern Science

50. THANK YOU BY k.venkatesh