Toxic Chemical Sensor Innovation

Clemson researchers advance nano-scale electromechanical sensors is a Clemson University news item providing information about a technological innovation which holds forth the possibility of detecting toxic gases or chemicals through devices employing nano-scale cantilevers which are small and capable of being held in hand.

The nano-scale cantilevers can be smaller than the width of a human hair and able to relay messages as a result of their vibration. Devices may be able to measure temperature and humidity changes in addition to detecting environmental toxins. Quoting from the linked article:

Preliminary results indicate that this fully electrical sensing scheme is so sensitive that it can differentiate between hydrogen and deuterium gas, very similar isotopes of the same element. Since the whole process is electrical, the size limitations that plague competing detection methods are not a problem here. The cantilevers can be shrunk down to the nano-scale and the operating electronics can be contained on a single tiny chip. Rao’s research has shown that a single carbon nanotube can be used as a vibrating cantilever.

Rao credits Clemson Professor Emeritus of Physics Malcolm Skove, who discovered that measuring the resonant frequency of a cantilever at the second or higher harmonies would get rid of the so-called parasitic capacitance, an unwanted background that obscures the signal and has been a major stumbling block to the advancement of similar technology.