Chemically Tailoring Semiconducting Two-Dimensional Transition Metal Dichalcogenides and Black Phosphorus

TL;DR

This paper reviews how chemical modifications can be used to tailor the electronic, optical, and physical properties of 2D transition metal dichalcogenides and black phosphorus, addressing challenges and opportunities for device integration.

Contribution

It provides a comprehensive overview of chemical strategies to modify 2D semiconductors, highlighting both degradation issues and methods to enhance their properties for applications.

Findings

Chemical modifications can significantly tune electronic properties.

Surface chemistry impacts material stability and performance.

Passivation schemes are crucial for device reliability.

Abstract

Two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDCs) and black phosphorus (BP) have beneficial electronic, optical, and physical properties at the few-layer limit. As atomically thin materials, 2D TMDCs and BP are highly sensitive to their environment and chemical modification, resulting in a strong dependence of their properties on substrate effects, intrinsic defects, and extrinsic adsorbates. Furthermore, the integration of 2D semiconductors into electronic and optoelectronic devices introduces unique challenges at metal-semiconductor and dielectric-semiconductor interfaces. Here, we review emerging efforts to understand and exploit chemical effects to influence the properties of 2D TMDCs and BP. In some cases, surface chemistry leads to significant degradation, thus necessitating the development of robust passivation schemes. On the other hand, appropriately designed chemical modification can be used to beneficially tailor electronic properties, such as controlling doping levels and charge carrier concentrations. Overall, chemical methods allow substantial tunability of the properties of 2D TMDCs and BP, thereby enabling significant future opportunities to optimize performance for device applications.