Lawrence Livermore researchers have developed a nanosensor that relies on semiconductor nanowires rather than traditional batteries as a power source. The device overcomes the power requirement of traditional sensors and is simple, highly sensitive, and can detect various molecules quickly. Its development could be the first step in making an easily deployable chemical sensor for the battlefield.

The nanosensors take advantage of a unique interaction between chemical species and semiconductor nanowire surfaces that stimulate an electrical charge between the two ends of nanowires or between the exposed and unexposed nanowires.

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Also: Learn about a carbon-nanotube-based chemical gas sensor developed at NASA's Jet Propulsion Laboratory.