Writing in Prospect Magazine Michael Gross surveys the field of nanotechnology and points out a surprising (at least to me) widely available use of nanotechnology:
The first nanotechnology breakthrough outside the information technology market is the microfabricated impact sensor to trigger airbags in cars. The new kind of sensor is based on a Mems (micro-electromechanical system) device, which means that it is fabricated by the same kind of technology as a computer chip, only that its function is mainly mechanical rather than electronic. When it was introduced in 1995, it turned out to be not only smaller and more efficient than the sensors previously available, but also 100 times cheaper. Understandably, it took over the world market in a matter of months.
But how about products designed from molecules upwards? There is at least one that you can buy already. It is the self-cleaning window. It uses a combination of two clever molecular tricks. First, it contains a catalyst that uses the energy of light to oxidise common kinds of dirt, to convert them into smaller, more soluble molecules that wash away with rain water. At this point, the second trick comes in. Ordinary glass is fairly water-repellent (hydrophobic), which means that water does not cover it smoothly, but tends to form droplets. The surface of self-cleaning glass, however, is coated in molecules that attract water and encourage it to spread out. So, instead of sitting around as drops which leave drying spots when they evaporate, the rain will cover the surface evenly, dissolve what the photocatalyst made of the dirt, and run off. Simple. Yet it would not be possible without molecular design on the nanometre scale.
|Share |||Randall Parker, 2002 November 21 05:22 PM Nanotech Advances|