Fabrication of mixed-dimensional van der Waals PbI2/SnS heterostructures and their optoelectronics

초록

The van der Waals (vdW) heterostructures composed of layered semiconductors have substantial potential for optoelectronic applications, including light-emitting diodes, lasers, and photodetectors. The bandgap of such heterostructures can be modulated by controlling charge/exciton transfer at the interface under given layer configurations. Here, we demonstrate the fabrication of mixed-dimensional heterostructures comprising two-dimensional (2D) layered tin sulfide (SnS) and one-dimensional (1D) lead iodide (PbI2) vdW semiconductor materials. Type I band alignment at the heterointerface facilitates the exciton transfer from PbI2 to SnS, which results in the enhanced excitonic emission of SnS, as confirmed by luminescence spectroscopy. Our results highlight the importance of bandgap engineering via vdW contact and pave the way to the relevant optoelectronic applications.