| AVS 59th Annual International Symposium and Exhibition | |
| Graphene and Related Materials Focus Topic | Thursday Sessions |
| Session GR-ThP |
| Session: | Graphene and Related Materials Poster Session |
| Presenter: | Q. Ma, University of California Riverside |
| Authors: | Q. Ma, University of California Riverside D.Z. Sun, University of California Riverside W.H. Lu, University of California Riverside D. Le, University of Central Florida M. Amanpour, University of Central Florida J. Mann, University of California Riverside S. Bobek, University of California Riverside T. Raman, University of Central Florida L. Bartels, University of California Riverside |
| Correspondent: | Click to Email |
MoS2 is a very promising material for photocatalysis and it has many current applications in catalytic hydrodesulfurization. Similar to graphene, it is a layered material. Recently, it has been shown that it transitions from an 1.6 eV inidirect bandgap to a 1.9 eV direct bandgap semiconductor when reduced to a monolayer. Important for its usefulness e.g. in catalytic hydrogen splitting, is not only its bandgap but also its band alignment when deposited on different substrates. Using CVD grown MoS2 on a copper surface, we use XPS to ascertain the identity of the material and the nature of its internal bonding when on this metallic substrate. Spectroscopy also shows a metal induced reduction of the bandgap to 1.5 eV and a strong signature of n-type doping through the underlayer. Density Functional Theory calculation corroborate this finding and provide a microscopic understanding of the bandgap and alignment depending on the number of MoS2 layers and the presence of any substrate.