Hydrogenated ψ-graphene as an ultraviolet optomechanical sensor

PSI (psi)-graphene is a dynamically and thermally stable two-dimensional (2D) allotrope of carbon composed of 5-6-7 carbon rings. Herein, we study the opto/mechanical behavior of two graphene allotropes, psi-graphene and its hydrogenated form, psi-graphane under uniaxial and biaxial strain using density functional theory (DFT) calculations. We calculated the elastic constants and second Piola-Kirchhoff (PK2) stresses, in which both nanostructures indicate a similar elasticity behavior to graphene. Also, the plasmonic behavior of these structures in response to various strains has been studied. As a result, plasmonic peaks varied up to about 2 eV under strain. Our findings reveal that these two structures have a large peak in the ultraviolet (UV) region and can be tuned by different applied strain. In addition, psi-graphene has smaller peaks in the IR and UV regions. Therefore, both psi-graphene and psi-graphane can be used as UV optomechanical sensors, whereas psi-graphene could be used as an infrared (IR) and visible sensor.