Tunable Photoluminescence of Monolayer MoS2 via Chemical Doping

TL;DR

This paper demonstrates that chemical doping can effectively tune the photoluminescence of monolayer MoS2 by controlling exciton and trion states, enabling adjustable optical and electrical properties.

Contribution

It introduces a solution-based chemical doping method to reversibly modulate PL intensity and carrier density in monolayer MoS2, a novel approach for optoelectronic applications.

Findings

PL intensity is enhanced by p-type dopants

PL intensity is reduced by n-type dopants

Carrier injection and extraction are achieved through chemical doping

Abstract

We demonstrate the tunability of the photoluminescence (PL) properties of monolayer (1L)-MoS2 via chemical doping. The PL intensity of 1L-MoS2 was drastically enhanced by the adsorption of p-type dopants with high electron affinity, but reduced by the adsorption of n-type dopants. This PL modulation results from switching between exciton PL and trion PL depending on carrier density in 1L-MoS2. Achievement of the extraction and injection of carriers in 1L-MoS2 by this solution-based chemical doping method enables convenient control of optical and electrical properties of atomically thin MoS2.