1D GeS/2D WSe2 Mixed-Dimensional van der Waals Heterostructures for Enhanced Radiative Recombinations

초록

Mixed-dimensional heterostructures composed ofvan der Waals (vdW) layered semiconductor materials provide a versatile platform for applications in optoelectronic devices, photocatalysis, and transistors. Here, we demonstrate a mixed-dimensional heterostructure consisting of 2D tungsten diselenide (WSe2) and 1D germanium sulfide (GeS) nanowires that exhibits substantial luminescence enhancement. GeS nanowire grown via the vapor?liquid?solid (VLS) technique show a 1D morphology with distinct sidewall facetorientations, forming unique interfacial atomic registries upon vdWheterojunction fabrication. The particular sidewall facets of the GeS nanowires determine the efficiency of the radiative recombination process, yielding enhancements up to 492 %. We propose that this emission enhancement is driven by a type I band structure at the interface, which increases both electron and hole densities at the heterojunction. Overall, this mixed-dimensional heterostructure demonstrates strong potential for next-generation optoelectronic applications.