Selective Gas Sensing with a Single Pristine Graphene Transistor

TL;DR

This study demonstrates that a single pristine graphene transistor can selectively detect different gases by analyzing changes in low-frequency noise spectra, eliminating the need for surface functionalization or multiple devices.

Contribution

The paper introduces a novel gas sensing method using low-frequency noise spectra of graphene, enabling selectivity without surface modification or device arrays.

Findings

Different gases produce distinguishable effects on noise spectra.

Characteristic Lorentzian frequencies vary for different chemicals.

Selective sensing achieved with a single graphene transistor.

Abstract

We show that vapors of different chemicals produce distinguishably different effects on the low-frequency noise spectra of graphene. It was found in a systematic study that some gases change the electrical resistance of graphene devices without changing their low-frequency noise spectra while other gases modify the noise spectra by inducing Lorentzian components with distinctive features. The characteristic frequency fc of the Lorentzian noise bulges in graphene devices is different for different chemicals and varies from fc=10 - 20 Hz to fc=1300 - 1600 Hz for tetrahydrofuran and chloroform vapors, respectively. The obtained results indicate that the low-frequency noise in combination with other sensing parameters can allow one to achieve the selective gas sensing with a single pristine graphene transistor. Our method of gas sensing with graphene does not require graphene surface functionalization or fabrication of an array of the devices with each tuned to a certain chemical.