Ab-initio study of gold nanoparticles supported on defect-laden single-layer MoS2

We have investigated the geometry, electronic structure, and catalytic properties of gold nanoparticles on defect-laden single-layer MoS$_{2}$ using density functional theory (DFT) based calculations with semi-empirical van der Waals interaction (DFT-D3). Our results show that the two-dimensional planar structure, the most favorable one for unsupported Au$_{13}$ nanoparticle, transforms into a distorted three-dimensional (3D) structure when supported on single-layer MoS$_{2}$ with single S-vacancy which is more favorable than the icosahedral, decahedron and cuboctahedron forms. The MoS$_{2}$ support substantially alters the electronic structure of Au$_{13}$ nanoparticle near the Fermi level, owing to the strong interaction of MoS$_{2}$ support with Au$_{13}$ in the presence of an S-vacancy. The modified electronic structure remarkably affects the catalytic activity of the MoS$_{2}$-supported Au$_{13}$, offering enhanced activity towards methanol synthesis reaction via CO hydrogenation reaction - a contrast from that of titania-supported Au$_{13}$ nanoparticle [1] which promotes methanol decomposition. [1] S. Hong and T. S. Rahman, JACS, 135, 7629 (2013)