Strong interlayer hybridization in the aligned SnS2/WSe2 hetero-bilayer structure
Source abstract
Abstract
Abstract 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 SnS2/WSe2 hetero-bilayer structure grown by chemical vapor deposition. Surprisingly, the valence band maximum position of WSe2 is moved from the K point for the single layer WSe2 to the Γ point for the aligned SnS2/WSe2 hetero-bilayer. Additionally, a significant photoluminescence quenching is observed for the SnS2/WSe2 hetero-bilayer structure with respect to the WSe2 monolayer. Using photoluminescence spectroscopy and nano-angle-resolved photoemission spectroscopy techniques, we demonstrate that the SnS2/WSe2 heterostructure present a type-II band alignment. These findings directly answer many outstanding questions about the electronic band structure and the band offset of SnS2/WSe2 hetero-bilayers for envisaging their applications in nanoelectronics.
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Research context
OpenAlex topics: 2D Materials and Applications · Perovskite Materials and Applications · MXene and MAX Phase Materials
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (39)
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