NANOTECHNOLOGY: Size DOES Matter

Chemical Sensors 

(I:Ch:1) 

"Atomic force microscopy image of island growth in between two electrodes (left and right) of the SAMFET. The self-assembled monolayer islands, in the middle of the figure, conduct charges. In this case, no path is formed between the two electrodes and therefore current cannot flow. The height of the molecules is 3 nanometers; the length of the gap between the electrodes (i.e. the transistor channel length) is 5 microns." (Ch:1)

With nanotechnology, sensors could be able to detect even the smallest amounts of chemical vapors. "Various types of detecting elements, such as carbon nanotubes, zinc oxide nanowires or palladium nanoparticles can be used in nanotechnology-based sensors." The size of nanotubes, nanowires, or nanoparticles allows the detection of low concentrations of chemical vapors. The capability of producing microscopial, inexpensive sensors provides a kind of "nano-bloodhound that doesn't need sleep or exercise" could be useful in many ways. "An obvious application is to mount these sensors throughout an airport, or any facility with security concerns, to check for vapors given off by explosive devices. These sensors can also be useful in industrial plants that use chemicals in manufacturing to detect the release of chemical vapors." (Ch:2)