Regensburg 2019 – wissenschaftliches Programm
O 66.7: Poster
Mittwoch, 3. April 2019, 17:45–20:00, Poster B2
A Two-dimensional Sub-stoichiometric Molybdenum Sulfide with Catalytically Active Basal Planes — Yang Bao1,2, Ming Yang3, and •Kianping Loh1 — 1Department of Chemistry, National University of Singapore, 117543 Singapore — 2TUM Fakultät für Physik, James-Franck-Straße 1, 85748 Garching bei München — 3Institute of Materials Research and Engineering, 117602, Singapore
2D molybdenum disulfide (MoS2) has attracted immense interests recently due to its remarkable optoelectronic and catalytic properties. Other than the thermodynamically stable MoS2 structure, different metastable, sub-stoichiometric phases of MoSx (x<2) may exist due to the versatile Mo-S coordination, which may offer unique functionalities not seen in MoS2. While 0D [Mo3S13]2- cluster (Kibsgaards et al. Nat Chem 6, 248-253, 2014) and 1D Mo6S6 wire (Lin et al. Nat Nano 9, 436-442, 2014) have been reported, 2D phases of MoSx compounds are less well studied. Under-coordinated atoms in such 2D Mo-S polymorphs may give rise to periodic spin textures or chemically reactive surface sites.
Here we report the discovery of a 2D sub-stoichiometric MoSx (x<2) phase, where interesting structural features such as undercoordinated surface sites were clearly revealed by surface characterization techniques. Density function theory (DFT) studies suggest that 2D-MoSx may have a Mo18S18 unit cell. We have carried out catalytic studies on its basal plane and observed its ability to catalyze oligomerization of molecules as well as the activation of molecular hydrogen into atomic hydrogen.