Charge Redistribution Mechanisms in SnSe₂ Surfaces Exposed to Oxidative and Humid Environments and Their Related Influence on Chemical Sensing.

ABSTRACT: Tin diselenide (SnSe₂) is a van der Waals semiconductor, which spontaneously forms a subnanometric SnO₂ skin once exposed to air. Here, by means of surface-science spectroscopies and density functional theory, we have investigated the charge redistribution at the SnO₂-SnSe₂ heterojunction in both oxidative and humid environments. Explicitly, we find that the work function of the pristine SnSe₂ surface increases by 0.23 and 0.40 eV upon exposure to O₂ and air, respectively, with a charge transfer reaching 0.56 e^-/SnO₂ between the underlying SnSe₂ and the SnO₂ skin. Remarkably, both pristine SnSe₂ and defective SnSe₂ display chemical inertness toward water, in c

SUBMITTER: D'Olimpio G 

PROVIDER: S-EPMC8015219 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature