Plasmons on the edge of MoS2 nanostructures

TL;DR

This study predicts the existence of 1D edge plasmons in MoS2 nanoribbons using ab initio calculations, highlighting their potential for tuning photocatalytic activity.

Contribution

First ab initio prediction of atomically confined edge plasmons in MoS2 nanostructures, with detailed analysis of their origin and properties.

Findings

Edge plasmons are localized on sulfur dimers at Mo edge.

Distinct plasmonic properties differentiate Mo and S edges.

Edge plasmons could be used to tune photocatalytic activity.

Abstract

Using ab initio calculations we predict the existence of one-dimensional (1D), atomically confined plasmons at the edges of a zigzag MoS2 nanoribbon. The strongest plasmon originates from a metallic edge state localized on the sulfur dimers decorating the Mo edge of the ribbon. A detailed analysis of the dielectric function reveals that the observed deviations from the ideal 1D plasmon behavior result from single-particle transitions between the metallic edge state and the valence and conduction bands of the MoS2 sheet. The Mo and S edges of the ribbon are clearly distinguishable in calculated spatially resolved electron energy loss spectrum owing to the different plasmonic properties of the two edges. The edge plasmons could potentially be utilized for tuning the photocatalytic activity of MoS2 nanoparticles.