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

• sp2 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

11,28

中國時報

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 weightThin and flexibleWorking temp -20 ~ 45 CEnvironment-friendly Incorporation with solar cell

DrawbackNeed frequent recharge Linz Univ. Austria

A recent breakthrough

What’s next?

(Physics Today, this Sep)