title: Chemically Tailoring Semiconducting Two-Dimensional Transition Metal Dichalcogenides and Black Phosphorus.
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.
authors.affiliation: Department of Materials Science and Engineering, Northwestern University , Evanston, Illinois 60208, United States.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Ryder
authors.affiliation: Department of Materials Science and Engineering, Northwestern University , Evanston, Illinois 60208, United States.
authors.forename: Joshua D
authors.initials: JD
authors.lastname: Wood
authors.affiliation: Department of Materials Science and Engineering, Northwestern University , Evanston, Illinois 60208, United States.
authors.forename: Spencer A
authors.initials: SA
authors.lastname: Wells
authors.affiliation: Department of Materials Science and Engineering, Northwestern University , Evanston, Illinois 60208, United States.|Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States.|Department of Medicine, Northwestern University , Evanston, Illinois 60208, United States.|Department of Electrical Engineering and Computer Science, Northwestern University , Evanston, Illinois 60208, United States.
authors.forename: Mark C
authors.initials: MC
authors.lastname: Hersam
keywords: anisotropy; chemistry; contacts; covalent; electronics; excitons; noncovalent; optoelectronics