The discovery of plastic conductors Hideki Shirakawa ( 白川英樹 ) Alan MacDiarma Alan Heeger

Advantages of plastic conductor light-weight, flexible, cheap, soluble --> printable

Conjugated polymer sp 2 bonding 聚乙炔 (poly-acetylene, 1958) π- electrons delocalized along the chain Dimerization opens an energy gap 2-3 eV (Peierls instability)

Other uses of "Synthetic Metals" Semiconductor devices Polymer LED (PPV) Plastic field-effect transistor All-plastic battery (PPy) Anti-static film, carpet... chemical vapor sensor… etc

PPV, 聚對苯乙烯 Friend, Cambridge Univ. Alan Heeger, UNIAX

Advantages Light-weight, flexible (rollable), cheap Flat-panel light Versatile side-groups for different colors

Spin-coating, thickness=100 nm

10/12 明日報

Live demo of “solid-state” LED street-light Philips

2400 transistors

Various conjugated polymers EM shielding “smart” window LED FET anode “Stealth” coating cathode

Poehler and Searson, Johns Hopkins Univ. n p

The All-Plastic Battery 1. Generate up to 3 Volts 2. Rechargeable for hundreds of cycles Advantages Light in weight Thin and flexible Working temp -20 ~ 45 C Environment-friendly Incorporation with solar cell Drawback Need frequent recharge Linz Univ. Austria

A recent breakthrough What’s next? (Physics Today, this Sep)