Abstract

An electride is a type of ionic material where an electron localized in a void acts in place of an anion. A wide variety of electrides have been synthesized, spanning many stoichiometries and geometries. From a theory perspective, they are of interest for their chemical and material applications, and for their unique electronic structure. A sub-class of electrides are those that are also layered materials, featuring electrons in the interlayer spacing. Modelling these materials with density-functional theory (DFT) requires a sufficient theoretical framework that accounts for dispersion forces and uses a basis set that can capture the electride states. Their large exfoliation energies and small coefficients of thermal expansion make layered electrides unique among the family of layered materials. One application that could leverage the appealing properties of layered electrides is to improve charge transfer across metal/MoS2 heterojunctions. Constructing low-resistance contacts is currently a major challenge for the semiconductor industry, and the insertion of a monolayer electride (Ca2N) to from a metal/Ca2N/MoS2 heterojunction could be the key to an Ohmic contact. Of interest is which metal(s) would be optimal for such a heterojunction.