Direct transformation of crystalline MoO$_3$ into few-layers MoS$_2$

TL;DR

This paper presents a method to directly convert crystalline MoO$_3$ into large-area, few-layer MoS$_2$ sheets at low temperatures, characterized by various techniques, with potential applications in electronics.

Contribution

The study introduces a low-temperature sulfurization process for fabricating large-area, few-layer MoS$_2$ from crystalline MoO$_3$, demonstrating a new synthesis route.

Findings

MoS$_2$ sheets are polycrystalline with 10-20 nm domains

Sheets reach up to 300x300 μm$^2$ in size

Films exhibit p-type electrical behavior

Abstract

We fabricate large-area atomically thin MoS$_2$ layers through the direct transformation of crystalline molybdenum MoS$_2$ (MoO$_3$) by sulfurization at relatively low temperatures. The obtained MoS2 sheets are polycrystalline (~10-20 nm single-crystal domain size) with areas of up to 300x300 um$^2$ with 2-4 layers in thickness and show a marked p-type behaviour. The synthesized films are characterized by a combination of complementary techniques: Raman spectroscopy, X-ray diffraction, transmission electron microscopy and electronic transport measurements.