Work

Photoluminescence of Chemically and Electrically Doped Two-Dimensional Monolayer Semiconductors

Year: 2024

Type: article

Abstract: Two-dimensional (2D) transition metal dichalcogenide (TMDC) monolayers exhibit unique physical properties, such as self-terminating surfaces, a direct bandgap, and near-unity photoluminescence (PL) quantum yield (QY), which make them attractive for electronic and optoelectronic applications. Surface charge transfer has been widely used as a technique to control the concentration of free charge in 2D semiconductors, but its estimation and the impact on the optoelectronic properties of the material remain a challenge. In this work, we investigate the optical properties of a WS2 monolayer under three different doping approaches: benzyl viologen (BV), potassium (K), and electrostatic doping. Owing to the excitonic nature of 2D TMDC monolayers, the PL of the doped WS2 monolayer exhibits redshift and a decrease in intensity, which is evidenced by the increase in trion population. The electron concentrations of 3.79×1013 cm−2, 6.21×1013 cm−2, and 3.12×1012 cm−2 were measured for WS2 monolayers doped with BV, K, and electrostatic doping, respectively. PL offers a direct and versatile approach to probe the doping effect, allowing for the measurement of carrier concentration in 2D monolayer semiconductors.

Source: Materials

DOI: 10.3390/ma17163962

Authors: Hyungjin Kim, Valerio Adinolfi, Sin-Hyung Lee

Institutions: Yonsei University, University of California, Berkeley, University of Seoul

Language: English

Topic: 2D Materials and Applications

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,955