快猫短视频

ULTRATHIN wires made from cobwebs could spark a revolution in miniature
electronics. Researchers in Germany have cut spider-silk threads to about
one-twentieth of their normal diameter without weakening them.

Coating the thinned silk threads with conducting metal would create far
stronger nanowires than normal, and they could be used anywhere. Usually
nanowires have to be grown on a supporting surface because they are so
fragile.

Michael Stuke and Markus Koch at the Max Planck Institute for Biophysical
Chemistry in G枚ttingen thought that silk from the black widow spider would
be the ideal raw material for nanowires. Spider silk is remarkably strong and
will stretch a lot before it snaps.

Stuke used pulses from an ultraviolet laser to pare away the surface of the
spider鈥檚 thread, removing 50 nanometres at a time. However, the early trials
were unsuccessful because the light pitted the silk鈥檚 surface, which seriously
weakened the thread.

But by firing lasers at the silk from opposite directions, Stuke found he
could evenly shave layers off the silk. The researchers managed to reduce the
silk from its usual diameter of between 3 and 5 micrometres down to 100
nanometres without weakening it.

The pair of researchers now plan to make conducting nanowires up to a metre
long by electroplating the thread with metal. Stuke and Koch are refining the
technique to make the thread even thinner. 鈥淲e want to see how thin we can make
these strands and still retain their properties,鈥� says Stuke.