Adsorption of gas molecules on graphene nanoribbons and its implication for nano-scale molecule sensor

TL;DR

This study investigates how gas molecules interact with graphene nanoribbons, revealing that NH3 significantly alters their electronic properties, enabling GNRs to function as selective sensors for ammonia detection.

Contribution

The paper provides first principles analysis of gas adsorption on GNRs, highlighting the potential for GNR-based sensors to detect NH3 selectively through electronic property changes.

Findings

NH3 adsorption induces n-type semiconducting behavior in GNRs.

Other gases have minimal impact on GNR conductance.

GNRs can selectively detect NH3 via electronic property modifications.

Abstract

We have studied the adsorption of gas molecules (CO, NO, NO2, O2, N2, CO2, and NH3) on graphene nanoribbons (GNRs) using first principles methods. The adsorption geometries, adsorption energies, charge transfer, and electronic band structures are obtained. We find that the electronic and transport properties of the GNR with armchair-shaped edges are sensitive to the adsorption of NH3 and the system exhibits n type semiconducting behavior after NH3 adsorption. Other gas molecules have little effect on modifying the conductance of GNRs. Quantum transport calculations further indicate that NH3 molecules can be detected out of these gas molecules by GNR based sensor.