Experimental and theoretical investigations of monolayer and few-layer talc

Abstract

We report experimental and theoretical investigations of a new nanomaterial: monolayer and few-layer talc. We show, through atomic force microscopy (AFM) measurements, that natural talc mineral can be mechanically exfoliated down to monolayer flakes. Our AFM-based mechanical characterization also shows that single- and few-layer talc flakes, of several square-microns, present properties similar to those of graphene, BN and MoS2, including the existence of folds and the recently reported negative dynamic compressibility. From first principles calculations, we also predict the mechanical properties of monolayer talc. We obtain theoretical values of monolayer talc breaking strength that are near graphene's record values and its 2D elastic modulus. We also predict that the flexural rigidity of monolayer talc should be more than thirty times larger than that of graphene, but that it could still be bent to very small curvatures without fracturing.