WS2 monolayer-based light-emitting devices in a vertical p–n architecture

Abstract

2D semiconductors represent an exciting new material class with great potential for optoelectronic devices. In particular, WS₂ monolayers are promising candidates for light-emitting devices (LEDs) due to their direct band gap with efficient recombination in the red spectral range. Here, we present a novel LED architecture by embedding exfoliated WS₂ monolayer flakes into a vertical p–n layout using organic p- and inorganic n-supporting layers. Laser lithography was applied to define the current path perpendicular to the WS₂ flake. The devices exhibit rectifying behavior and emit room temperature electroluminescence with luminance up to 50 cd m⁻² in the red spectral range.