Electrochemical intercalation of discrete van der Waals heterostructures

Engineering van der Waals hetero interface for controlling electronic and ionic charge is a challenging problem. In electrochemical energy storage systems, mobile ions reversibly associate with a host lattice by adsorption or insertion/intercalation into vacant sites, such as the interface gaps of van der Waals materials. In this presentation, we will discuss the electro-intercalation of lithium at the level of vdW heterostructures layers comprised of deterministically stacked hexagonal boron nitride (hBN), graphene, and molybdenum dichalcogenide (MoCh₂; Ch = S, Se) layers, enabling the direct resolution of intermediate stages in the intercalation of discrete heterointerfaces and the extent of charge transfer to individual layers. Using magnetoresistance and spectroscopic data as probes of reaction progress coupled with low-temperature quantum magneto-oscillation measurements, these studies at well-defined mesoscopic electrodes show that the creation of intimate vdW heterointerfaces is a powerful knob for modulating intercalation potentials and tuning ion capacities of 2D interfaces.