Presentation is loading. Please wait.

Presentation is loading. Please wait.

Nanochemistry in the New Leaving Certificate Chemistry Syllabus

Similar presentations


Presentation on theme: "Nanochemistry in the New Leaving Certificate Chemistry Syllabus"— Presentation transcript:

1 Nanochemistry in the New Leaving Certificate Chemistry Syllabus
Dr Justin D. Holmes 30th Annual ChemEd Conference, UCC 22 Oct 2011 1

2 Draft Chemistry Syllabus (Leaving Certificate)
Unit 2: Properties, Structure and Bonding Students learn about Student should be able to 2.6 Technological applications of chemistry  Discuss the terms : nanoscience, nanochemistry and nanotechnology  Describe and discuss how incorporation of carbon nanotubes into polymer composites can alter the mechanical properties of these composites  Describe/discuss the electronic properties and potential applications of carbon nanotubes 2

3 What is Nanoscience, Nanochemistry and Nanotechnology?
Nanoscience - the study of matter at very small length scales: 100 nanometres and below. Nanochemistry – the synthesis of nanoscale building blocks of different size, shape, composition, surface structure, charge and functionality. Nanotechnology - the products that are derived from this knowledge So what is the big deal? Novel and sometimes unexpected properties….. Can design materials to have specific properties Small matter is constantly moving…can arranges itself to form interesting and useful objects, e,g. part of a computer chip, or cure for cancer…but you need to know the rules! Gravity doesn’t matter (its there, just really weak) Sticky (intermolecular forces) Shaky (thermal energy) Bumpy (Quantum effects) 3

4 What is a Nanometre? Nanos [Greek]: the dwarf 1mm
A Nanometre is a millionth fraction of a millimetre 4

5 1 nanometre length corresponds to five atoms side-by-side
How big: Atom compared to an apple? 1 nanometre length corresponds to five atoms side-by-side Atom Apple Earth © CRANN 09 3/31/2017 5

6 Nano: The Middle Ground
Subatomic/Nuclear Particle Molecular/Atomic Scale ? “Microscopic” “Nanoscopic” “Macroscopic” ? ? Galactic 1010 m 101 m 10-6 m 1020 m 10-9 m 10-15 m 10-10 m 6

7 Why the Hype about Nanotechology?
Internet search engine ~ 10 Million hits Nanotechnology is on the way to becoming the FIRST $Trillion Market The Individual Protection Directorate at the US Army Natick, has stated the next generation battle dress uniform (BDU) should aim to have the following properties: Waterproof Flame Resistant Built-in Insect Repellant Antimicrobial to protect injuries from infection Chemical and Biological agent protection Suppress odors Warmer in winter Cooler in Summer …..And lighter and less bulky that current solutions Nanotechnology affects almost every aspect of daily life, e.g. security or medicine 7

8 Nanotechology: Research to Applications
8

9 Remember the Transistor
Electron tube  Transistor Integrated circuits Notebook Mobile Phone Internet Remember the Transistor 9

10 Electronics & Molecules
Getting smaller and smaller Tube Transistor Chip Molecule ? $ Six-Core Core i7 1,170,000,000 2010 Intel 32 nm 240 mm² 5 cm 0.05 m 5 mm 0.005 m 5 mm 0.000,005 m < 5 nm < 0.000,000,005 m More transistors per laptop than people on planet Earth 10

11 New Materials: Lotus Effect
Nelumbo nucifera, the sacred Lotus flower. Nano is used in textiles mainly to provide stain-resistance or anti-bacterial properties. Some clothes made from these textiles can now be purchased in high-street shops, usually with these properties described on the tags attached, though they may not mention the words nano or nanotechnologies. Barthlott realized that the effect is caused by the combination of two features of the leaf surface: its waxiness and the microscopic bumps (a few microns in size) that cover it. He knew from basic physics that the waxiness alone should make the leaves hydrophobic, or water-hating. On such a material, drops of water sit up high to minimize their area of contact with the material. Water on a more hydrophilic, or water-loving, substance spreads across it to maximize the contact area. For a hydrophilic surface, the contact angle (where the droplet’s surface meets the material) is less than 30 degrees; a hydrophobic surface has a contact angle greater than 90 degrees. In addition, he understood that the innumerable bumps take things a step further and cause the lotus surface to be superhydrophobic—the contact angle exceeds 150 degrees, and water on it forms nearly spherical droplets with very little surface contact that roll across it as easily as ball bearings would. The water sits on top of the bumps like a person lying on a bed of nails. Air trapped between the water and the leaf surface in the spaces around the bumps increases the contact angle. 11

12 Stain Resistant Fabrics
No More Restaurant Disasters! Nano coatings (such as Teflon-like substances) are created and bond with the textile, so that little nano-sized molecular hooks attach to the fabric of the garment and the hair-like structures repel the water like the lotus leaf. But because these are nano-sized they don’t make the fabric stiff, so keeping the softness of whatever is coated. The fabric is a polyester base coated with silicone nanofibers. According to Lead Researcher Stefan Seeger this water repellent fabric concept is based on the combination of the hydrophobic surface chemistry and the nanostructure of the coating results in the super-hydrophobic effect. The water come to rest on the top of the nanofilaments like a fakir sitting on a bed of nails. Now we can understand the concept of these waterlogged dry cloths it is the finomina of surface tension just because of it water slips off from the surface of these special fabrics. This material lends itself to self cleaning materials, low drag swim suits and anything else where keeping dry or trapping micro-pockets of air might be of use. I think this beautiful combination is based on the tiny nanostructures is responsible for many natural examples of extreme water resistance, such as the surface of Lotus leaves. 12

13 Nanoparticles/Nanospheres in Cosmetics
 Small crystal size and controlled particle size: - give excellent dispersibility, - make skin feel attractive, - transparent on the skin  May increase protection against both UVA and UVB rays  Helps increase penetration of active material into skin 13

14 Scratch Resistant Materials
Engineers discovered that adding aluminum silicate nanoparticles to scratch-resistant polymer coatings made the coatings more effective, increasing resistance to chipping and scratching. Scratch-resistant coatings are common on everything from cars to eyeglass lenses. NanoTek® Aluminium Oxide Nanoparticles 14

15 Therapies Based on Nanoparticles
Antibody that recognises cancer cell Drugs for release “Magic Bullets”…specifically designed to target cancer cells 15

16 But that’s not all - Small Stuff is Always Moving
Diffusion of oxygen vacancies on TiO2(110) surfaces Prof. F. Besenbacher, iNano Centre, Aarhus University, Denmark Aggregation of Nano-Au Materials Chemistry & Analysis Group, UCC 16

17 Various Forms of Carbon
Allotropes of carbon have different covalent bonding arrangements Carbon atoms form covalent bonds by sharing outer shell electrons with each other Diamond, graphite, buckyballs and carbon nanotubes all have different covalent arrangements of carbon atoms The differing covalent arrangements of carbon atoms lead to the different properties of carbon allotropes 17

18 Properties of Carbon Allotropes
++++++ + No +++++ Conducts Electricity ++++ Buckyballs Carbon Nanotubes +++ Not Known Diamond ++ Graphite Coal Conducts Heat Tensile Strength Hardness Allotrope 18

19 Unique Properties of Carbon Nanotubes
 200× stronger than steel - 1/16th weight  First synthetic material to have greater strength than spider silk  Excellent conductors of electricity and heat - similar to Cu  Have huge potential for product development 19

20 Structures of Carbon Nanotubes
Single-Walled Carbon Nanotubes (SWNTs) Multi-Walled Carbon Nanotubes (MWNTs) 20

21 Nanotube Composites: Electronic Paper
CRANN- HP Project  Flexible substrate  Light weight  High transparency  Good conductivity Prototype HP e-skins device 21

22 Nanotube Composites: Sporting Equipment
Badminton racquet manufacturer Yonex incorporates carbon nanotubes into their cup stack carbon nanotubes racquets (www.yonex.com) American baseball bat manufacturer Easton Sports has formed an alliance with a nanotechnology company Zyvex to develop baseball bats incorporating carbon nanotubes Tennis racquets also incorporate carbon nanotubes (www.babolat.com) Light weight  Strength  Bigger ‘sweet spot’ 22

23 Super Light and Strong Materials
BMC designs high-tech bicycle frame with carbon nanotubes 800 g 23

24 Metallic vs Semiconducting SWNTs
(0,0) Ch = (10,0) a1 a2 x y Metallic 24

25 Metallic vs Semiconducting SWNTs
Ch = (10,5) (0,0) a1 a2 x y Atomically resolved STM measurement of a carbon nanotube Chirality - twist of the nanotube Semiconducting 25

26 Electronic Properties of SWNTs
Diffusive Transport in Ordinary Materials Carriers are scattered in new directions by electrons, phonons, impurities and interfaces Ballistic Transport in Nanotubes Carriers cannot be scattered in new directions because no other directions are available 26

27 Electronic Applications of Carbon Nanotubes
27

28 Next Generation of Nanotube Technologies
Carbon nanotubes are being used to develop flat screen televisions with higher resolution than the human eye can detect Your next TV screen could be thin, ultra-light and foldable… Branching and switching of signals at electronic junctions is similar to what happens in nerves A carbon nanotube ‘neural tree’ can be trained to perform complex switching and computing functions Could be used to detect/respond to electronic, acoustic, chemical, biological or thermal signals. 28

29 Potential Health Risks of Nanomaterials
Carbon Nanotubes Quantum Dots ©Felice Frankel Engineered Nanoparticles  Critical factors: Surface Area Surface Chemistry Size - deposition probability and translocation Shape 29

30 Nanoscience – International Context
 Worldwide investment in nanotechnology research and development has increased over 20-fold in the last 12 years – from $432 million in 1997 to about $9,200 million in 2009.  Over 35 countries have now initiated national based activities in this space and the levels of investment are increasing. 30

31 Who is Winning the Nanoscience Race?
Top 10 Nations Ranked by Impact 1. Switzerland 2. Netherlands 3. United States 4. Canada 5. Belgium 6. Ireland 7. United Kingdom 8. Denmark 9. France 10. Japan 31

32 Nanoscience – Materials Research
Ireland now ranked 8th in the world in Materials Science! - Chemistry - Physics - Biology Source: Times Higher Education, August 26th 2010 32

33 The Future 33

34 Summary  Nanotechnology is the next wave!
 Will impact all sectors: from health care to next generation computers and communications - presently 10% of Irish exports are enabled by nanotechnology  Anticipated €1.5 trillion market by 2015  Ireland has critical mass of research excellence and world-class facilities Ireland is well positioned to catch the nanotech wave! Acknowledgements Prof John Boland (TCD, CRANN) Prof Georg Duesberg (CRANN / Infineon Technologies AG) National Nanotechnology Secondary School Resource An Australian Government Initiative (www.accessnano.org) 34


Download ppt "Nanochemistry in the New Leaving Certificate Chemistry Syllabus"

Similar presentations


Ads by Google