The Atomic and Electronic structure of 0{\deg} and 60{\deg} grain boundaries in MoS2

TL;DR

This study examines the atomic and electronic structures of 0° and 60° grain boundaries in monolayer MoS2, revealing structural differences and electronic shifts due to strain, with implications for material properties.

Contribution

It provides detailed atomic and electronic characterization of specific grain boundaries in MoS2, highlighting the effects of boundary angle and strain on electronic properties.

Findings

Perfectly stitched 0° boundary observed

Significant band shifts due to lattice strain

Grain boundary angle influences structure and electronic behavior

Abstract

We have investigated atomic and electronic structure of grain boundaries in monolayer MoS2, where relative angles between two different grains are 0 and 60 degree. The grain boundaries with specific relative angle have been formed with chemical vapor deposition growth on graphite and hexagonal boron nitride flakes; van der Waals interlayer interaction between MoS2 and the flakes restricts the relative angle. Through scanning tunneling microscopy and spectroscopy measurements, we have found that the perfectly stitched structure between two different grains of MoS2 was realized in the case of the 0 degree grain boundary. We also found that even with the perfectly stitched structure, valence band maximum and conduction band minimum shows significant blue shift, which probably arise from lattice strain at the boundary.