Analysis of lizardite-graphene van der Waals heterostructures: A DFT study

Graphene has garnered significant attention not just for its intriguing properties but also for its role as a pioneer among 2D van der Waals materials. The amalgamation of graphene with other crystals to form heterostructures provide a path for engineering and manipulating new physics and device properties. In this work, we investigate the vdW heterostructures formed by assembling graphene and the clay-mineral lizardite, a clay-mineral that is abundant in nature and represents the most stable polymorph of the serpentine family. The electronic and optical properties of three distinct heterostructures are presented to discern the characteristics of the systems. We observe that all the three heterostructures exhibit a metallic nature. Yet, computations using the Heyd-Scuseria-Ernzerhof hybrid functional (HSE) approach suggest the emergence of an energy gap, unveiling the semi-conductor characteristics of the heterostructures. Additionally, unlike lizardite, the heterostructures demonstrate polarization-dependent optical properties. The study of the assembled structures combining the clay-mineral with graphene not only widens the spectrum of vdW heterostructures but also explores their potential within the context of the serpentine family.