An unusual parameter – low-frequency electronic noise – could be exploited to make selective and highly sensitive gas sensors based on pristine graphene. The finding means that the material no longer has to be functionalized for it to be able to detect different gases, nor does an array of devices (with each tuned to detect a certain chemical) need to be made.
“We found that adsorbed gases modify graphene’s low-frequency noise spectra by inducing ‘Lorentzian’ components with distinctive features,” explained team leader Alexander Balandin of the University of California Riverside. “The characteristic frequency, fc of the Lorentzian noise bulges in graphene devices and is different for different chemicals, varying from fc = 10–20 Hz to fc = 1300–1600 Hz for tetrahydrofuran and chloroform vapours respectively….
http://nanotechweb.org/cws/article/tech/49618