Continuous Heteroepitaxy of Two-Dimensional Heterostructures Based on Layered Chalcogenides

The in-plane connection and layer-by-layer stacking of atomically-thin layered materials are expected to allow the fabrication of two-dimensional (2D) heterostructures with exotic physical properties and future engineering applications. However, it is currently necessary to develop a continuous growth process that allows the assembly of a wide variety of atomic layers without interface degradation, contamination and/or alloying. Herein, we report the continuous heteroepitaxial growth of 2D multi-heterostructures and nanoribbons based on layered transition metal dichalcogenide (TMDC) monolayers, employing metal organic liquid precursors with high supply controllability. This versatile process can avoid air exposure during growth process, and enables the formation of in-plane heterostructures with ultra-clean atomically sharp and zigzag-edge straight junctions without defects or alloy formation around the interface. For the samples grown directly on graphite, we have investigated the local electronic densit...