Superposition of semiconductor and semi-metal properties of self-assembled 2D SnTiS3 heterostructures

Srinivasa Reddy Tamalampudi, Jin-You Lu, Nitul Rajput, Chia-Yun Lai, Boulos Alfakes, Raman Sankar, Harry Apostoleris, Shashikant P. Patole, Ibraheem Almansouri, Matteo Chiesa
2020 npj 2D Materials and Applications  
Two-dimensional metal dichalcogenide/monochalcogenide thin flakes have attracted much attention owing to their remarkable electronic and electrochemical properties; however, chemical instability limits their applications. Chemical vapor transport (CVT)synthesized SnTiS 3 thin flakes exhibit misfit heterojunction structure and are highly stable in ambient conditions, offering a great opportunity to exploit the properties of two distinct constituent materials: semiconductor SnS and semi-metal TiS
more » ... 2 . We demonstrated that in addition to a metal-like electrical conductivity of 921 S/cm, the SnTiS 3 thin flakes exhibit a strong bandgap emission at 1.9 eV, owing to the weak van der Waals interaction within the misfit-layer stackings. Our work shows that the misfit heterojunction structure preserves the electronic properties and lattice vibrations of the individual constituent monolayers and thus holds the promise to bridge the bandgap and carrier mobility discrepancy between graphene and recently established 2D transition metal dichalcogenide materials. Moreover, we also present a way to identify the top layer of SnTiS 3 misfit compound layers and their related work function, which is essential for deployment of van der Waals misfit layers in future optoelectronic devices. npj 2D Materials and Applications (2020) 4:23 ; https://doi.
doi:10.1038/s41699-020-0158-7 fatcat:wvpfgx6yyrfh3dl2kzefd7soai