Strain and Water Effects on the Electronic Structure and Chemical Activity of In-Plane Graphene/Silicene Heterostructure

TL;DR

This study uses first-principles calculations to explore how strain and water interaction affect the electronic structure and chemical activity of graphene/silicene heterostructures, revealing tunable properties for nanoelectronics and sensors.

Contribution

It demonstrates how strain and substrate influence the electronic and chemical properties of graphene/silicene heterostructures, enabling property modulation for device applications.

Findings

Heterostructure remains metallic under -7% to +7% strain.

Strain increases H2O binding energy and modulates charge transfer.

BN substrate significantly alters chemical activity and charge transfer.

Abstract

By using first-principles calculations, the electronic structure of planar and strained in-plane graphene/silicene heterostructure is studied. The heterostructure is found to be metallic in a strain range from -7% (compression) to +7% (tension). The effect of compressive/tensile strain on the chemical activity of the in-plane graphene/silicene heterostructure is examined by studying its interaction with the H2O molecule. It shows that compressive/tensile strain is able to increase the binding energy of H2O compared with the adsorption on a planar surface, and the charge transfer between the water molecule and the graphene/silicene sheet can be modulated by strain. Moreover, the presence of the boron-nitride (BN)-substrate significantly influences the chemical activity of the graphene/silicene heterostructure upon its interaction with the H2O molecule and may cause an increase/decrease of the charge transfer between the H2O molecule and the heterostructure. These findings provide insights into the modulation of electronic properties of the in-plane free-standing/substrate-supported graphene/silicene heterostructure, and render possible ways to control its electronic structure, carrier density and redox characteristics, which may be useful for its potential applications in nanoelectronics and gas sensors.