Departmental Papers (ESE)

Title

Intrinsic Response of Graphene Vapor Sensors

Document Type

Journal Article

Date of this Version

3-6-2009

Comments

Intrinsic Response of Graphene Vapor Sensors. Yaping Dan, Ye Lu, Nicholas J. Kybert, Zhengtang Luo, A. T. Charlie Johnson. Nano Letters 2009 9 (4), 1472-1475

http://dx.doi.org/10.1021/nl8033637

Abstract

Graphene is a two-dimensional material with extremely favorable chemical sensor properties. Conventional nanolithography typically leaves a resist residue on the graphene surface, whose impact on the sensor characteristics has not yet been determined. Here we show that the contamination layer chemically dopes the graphene, enhances carrier scattering, and acts as an absorbent layer that concentrates analyte molecules at the graphene surface, thereby enhancing the sensor response. We demonstrate a cleaning process that verifiably removes the contamination on the device structure and allows the intrinsic chemical responses of the graphene monolayer to be measured. These intrinsic responses are surprisingly small, even upon exposure to strong analytes such as ammonia vapor.

Date Posted: 03 November 2009

This document has been peer reviewed.