Investigation of the band alignment at MoS2/PtSe2 heterojunctions

In this work, large-area continuous monolayer-MoS2 and triple-layer-PtSe2 films are grown on Si substrates by chemical vapor deposition and the MoS2/PtSe2 heterostructures are fabricated using transfer technology. The energy band alignment at the heterojunction is investigated by employing x-ray photoelectron spectroscopy measurements, indicating a type-I band formed at the interface. The conduction and valence band offsets are determined to be 0.85 eV and 0.66 eV, respectively, which is consistent with the results deduced from the electron affinity. Furthermore, the enhancing improvement of light absorption in the visible region implies that this heterostructure has great potential in optoelectronic applications. This study provides promising guidance for the related device design and fabrication.