Tailoring properties of single layer transition metal dichalcogenides: looking beyond graphene

Single-layer of molybdenum disulfide (MoS$_{\mathrm{2}})$ and other transition metal dichalcogenides appear to be promising materials for next generation nanoscale applications (optoelectronic and catalysis), because of their low-dimensionality and intrinsic direct band-gap which typically lies in the visible spectrum. Several experimental groups have already reported novel electronic and transport properties which place these material beyond graphene for device applications. MoS$_{\mathrm{2\thinspace }}$is known to be a leading hydrodesulfurization catalyst. Efforts are underway to further tune these optoelectronic and catalytic properties through alloying, defects, doping, coupling to a substrate, and formation of bilayer stacks (homo- and hetro-structures). In this talk I will present results from joint theoretical and experimental investigations [1-3] which provide a framework for manipulating the functionality of this \textit{wundermaterial} and take us closer to the goal of rational material design. My emphasis will be on the structural, optical and catalytic properties of pure and defect-laden single layer MoS$_{\mathrm{2\thinspace }}$and their possible technological applications. [1] D. Sun, et al., Angew. Chem. Int. Ed. 51, 10284 (2012). [2] D. Le, T. B. Rawal, and T. S. Rahman, J. Phys. Chem. C 118, 5346 (2014). [3] T. Komesu, D. Le, et al., App. Phys. Lett. 105, 241602 (2014).