Postgrowth Tuning of the Bandgap of Single-Layer Molybdenum Disulfide Films by Sulfur/Selenium Exchange

We demonstrate bandgap tuning of a single-layer MoS2 film on SiO2/Si via substitution of its sulfur atoms by selenium through a process of gentle sputtering, exposure to a selenium precursor, and annealing. We characterize the substitution process both for S/S and S/Se replacement. Photoluminescence...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:ACS nano 2014-05, Vol.8 (5), p.4672-4677
Hauptverfasser: Ma, Quan, Isarraraz, Miguel, Wang, Chen S, Preciado, Edwin, Klee, Velveth, Bobek, Sarah, Yamaguchi, Koichi, Li, Emily, Odenthal, Patrick Michael, Nguyen, Ariana, Barroso, David, Sun, Dezheng, von Son Palacio, Gretel, Gomez, Michael, Nguyen, Andrew, Le, Duy, Pawin, Greg, Mann, John, Heinz, Tony. F, Rahman, Talat Shahnaz, Bartels, Ludwig
Format: Artikel
Sprache:eng
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:We demonstrate bandgap tuning of a single-layer MoS2 film on SiO2/Si via substitution of its sulfur atoms by selenium through a process of gentle sputtering, exposure to a selenium precursor, and annealing. We characterize the substitution process both for S/S and S/Se replacement. Photoluminescence and, in the latter case, X-ray photoelectron spectroscopy provide direct evidence of optical band gap shift and selenium incorporation, respectively. We discuss our experimental observations, including the limit of the achievable bandgap shift, in terms of the role of stress in the film as elucidated by computational studies, based on density functional theory. The resultant films are stable in vacuum, but deteriorate under optical excitation in air.
ISSN:1936-0851
1936-086X
DOI:10.1021/nn5004327