Sensing Properties of Lateral Graphene/h-BN Heterostructure towards NH3: A First Principles Study

Adsorption of NH3 molecule on graphene/hexagonal boron nitride heterostructure (G/h-BN) was investigated by applying density functional theory. Structural, electronic and adsorption properties of this heterostructure towards NH3 are reported. The N site at G/h-BN interface has been shown to have the highest adsorption energy and the amount of adsorption energy indicates a physical adsorption. Despite the weak interaction between the molecules and the surface, a measurable signal for sensing applications can be expected due to the sensitivity of tunneling current to the changes in electronic structure. Our results show that the proposed device could have a higher sensitivity comparing to the pristine graphene and pure h-BN.