Charge Redistribution Mechanisms in SnSe2Surfaces Exposed to Oxidative and Humid Environments and Their Related Influence on Chemical Sensing

Gianluca D'olimpio, Francesca Genuzio, Tevfik Onur Menteş, Valentina Paolucci, Chia Nung Kuo, Amjad Al Taleb, Chin Shan Lue, Piero Torelli, Daniel Fariás, Andrea Locatelli, Danil W. Boukhvalov, Carlo Cantalini, Antonio Politano

研究成果: Article同行評審


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 contrast to other metal chalcogenides. Conversely, the SnO2-SnSe2 interface formed upon surface oxidation is highly reactive toward water, with subsequent implications for SnSe2-based devices working in ambient humidity, including chemical sensors. Our findings also imply that recent reports on humidity sensing with SnSe2 should be reinterpreted, considering the pivotal role of the oxide skin in the interaction with water molecules.

頁(從 - 到)9003-9011
期刊Journal of Physical Chemistry Letters
出版狀態Accepted/In press - 2020

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Physical and Theoretical Chemistry

指紋 深入研究「Charge Redistribution Mechanisms in SnSe<sub>2</sub>Surfaces Exposed to Oxidative and Humid Environments and Their Related Influence on Chemical Sensing」主題。共同形成了獨特的指紋。