⚗️ Nanotechnology — What is it?

• Nanotechnology = science and engineering at the scale of 1–100 nanometres (nm)
• 1 nanometre = 10⁻⁹ metres = 1 billionth of a metre
• For comparison: human hair = ~80,000 nm wide; DNA molecule = ~2 nm wide; red blood cell = ~7,000 nm
• At nano scale, materials exhibit unique properties different from bulk materials (different colour, strength, conductivity)

⚗️ History of Nanotechnology

• Richard Feynman (1959) — lecture “There’s Plenty of Room at the Bottom” — conceptual birth of nanotechnology; called “Father of Nanotechnology”
• Norio Taniguchi (1974) — coined the term “nanotechnology”
• Scanning Tunnelling Microscope (STM) — invented 1981 by Gerd Binnig and Heinrich Rohrer — Nobel Prize Physics 1986 — key tool for nanotechnology
• IBM “IBM” logo (1989) — spelled using 35 xenon atoms — first demonstration of atomic manipulation

⚗️ Why Nano Scale is Special

• Quantum effects — at nano scale, quantum mechanics dominates; materials behave differently
• Increased surface area — nanoparticles have huge surface area relative to volume; more reactive
• Different optical properties — gold nanoparticles appear red/purple (not gold)
• Different electrical properties — carbon nanotubes conduct electricity better than copper
• Different mechanical properties — graphene is 200× stronger than steel