Tunable Doping in Hydrogenated Single Layered Molybdenum Disulfide

TL;DR

This study demonstrates that atomic hydrogen can be used to controllably dope single-layer MoS2 from n-type to p-type and saturate sulfur vacancies, offering a new method for tuning electronic properties of TMD materials.

Contribution

The paper introduces a room-temperature hydrogenation technique to tune doping and saturate vacancies in monolayer MoS2, advancing control over its electronic properties.

Findings

Hydrogenation enables reversible n- to p-type doping in MoS2.

Hydrogen incorporation saturates sulfur vacancies effectively.

High-quality electronic modifications confirmed by spectroscopy and DFT.

Abstract

Structural defects in the molybdenum disulfide (MoS2) monolayer are widely known for strongly altering its properties. Therefore, a deep understanding of these structural defects and how they affect MoS2 electronic properties is of fundamental importance. Here, we report on the incorporation of atomic hydrogen in mono-layered MoS2 to tune its structural defects. We demonstrate that the electronic properties of single layer MoS2 can be tuned from the intrinsic electron (n) to hole (p) doping via controlled exposure to atomic hydrogen at room temperature. Moreover, this hydrogenation process represents a viable technique to completely saturate the sulfur vacancies present in the MoS2 flakes. The successful incorporation of hydrogen in MoS2 leads to the modification of the electronic properties as evidenced by high resolution X-ray photoemission spectroscopy and density functional theory calculations. Micro-Raman spectroscopy and angle resolved photoemission spectroscopy measurements show the high quality of the hydrogenated MoS2 confirming the efficiency of our hydrogenation process. These results demonstrate that the MoS2 hydrogenation could be a significant and efficient way to achieve tunable doping of transition metal dichalcogenides (TMD) materials with non-TMD elements.