The structural, electronic and catalytic properties of Aun (n = 1–4) nanoclusters on monolayer MoS2
The structural stability, electronic and catalytic properties of Aun (n = 1–4) nanoclusters supported on monolayer MoS2 have been investigated based on first principle DFT calculation with van der Waals (vdW) corrections. Our results show that all Aun (n = 1–4) nanoclusters prefer to bind vertically on the top S sites of the monolayer MoS2. And the relative stability of Aun (n = 1–4) clusters in gas phase is not preserved after landing on monolayer MoS2. By including van der Waals (vdW) corrections with different approaches, we found that the van der Waals correction increased the adsorption energies for all supported Aun (n = 1–4) clusters with the order of Eads(PBE-D2) > Eads(PBE-D3) > Eads(optB86b-vdW) > Eads(PBE). And the van der Waals effects can also change the order of stability and the energy differences of various deposition configurations. In addition, the binding of O2 is also modeled, showing significantly enhanced adsorption properties and catalytic activation toward O2 adsorption, especially for that on supported Au1 and Au3 clusters with magnetic properties, with respect to that on supported Au2 and Au4 clusters with nonmagnetic properties. The current study provides further insight into the adsorption and catalytic properties of small gold clusters supported on monolayer MoS2, which play a crucial role in the activation of O2.