We report on the controlled growth of h-BN/graphite by means of molecular beam epitaxy (MBE). X-ray photoelectron spectroscopy (XPS) suggests an interface without any reaction or intermixing, while the angle resolved photoemission spectroscopy (ARPES) measurements show that the h-BN layers are epitaxially aligned with graphite. A well-defined band structure is revealed by ARPES measurement, reflecting the high quality of the h-BN films. The measured valence band maximum (VBM) located at 2.8 eV below the Fermi level reveals the presence of undoped h-BN films (band gap ~ 6 eV). These results demonstrate that, although only weak van der Waals interactions are present between h-BN and graphite, a long range ordering of h-BN can be obtained even on polycrystalline graphite via van der Waals epitaxy, offering the prospect of large area, single layer h-BN.

The combination of monolayers of different two-dimensional (2D) materials into van der Waals hetero-bilayer structures creates unprecedented physical phenomena, acting as a powerful tool for future devices. Understanding and exploiting these phenomena hinge on knowing the electronic structure and the hybridization of hetero-bilayer structures. Here, we show strong hybridization effects arising between the constitutive single layers of a SnS 2 /WSe 2 hetero-bilayer structure grown by chemical vapor deposition. Surprisingly, the valence band maximum position of WSe 2 is moved from the K point for the single layer WSe 2 to the Γ point for the aligned SnS 2 /WSe 2 hetero-bilayer. Additionally, a significant photoluminescence quenching is observed for the SnS 2 /WSe 2 heterobilayer structure with respect to the WSe 2 monolayer. Using photoluminescence spectroscopy and nano-angle-resolved photoemission spectroscopy techniques, we demonstrate that the SnS 2 /WSe 2 heterostructure present a type-II band alignment.These findings directly answer many outstanding questions about the electronic band structure and the band offset of SnS 2 /WSe 2 hetero-bilayers for envisaging their applications in nanoelectronics.