Structure and energetics of Ni and Au nanoclusters deposited on the (001), (110), and (111) surfaces of Au and Ni: A molecular dynamics study

Abstract

We present a comprehensive theoretical study---within the framework of the embedded-atom method---of the structural properties of Ni and Au nanoclusters deposited on the (001), (110), and (111) surfaces of Au and Ni, respectively, to characterize the evolution of the interfaces between nanoparticles and substrates. The Ni nanoclusters are found to exchange with the Au substrate atoms to form subsurface wetting layers. The exchanges occur either in a concerted fashion with the formation of a transient dimer, or in a two-step process consisting of complete insertion, then ejection of substrate atoms. Our results show a significant dependence of the shape of the embedded nanocluster on the surface, temperature, and contact angle. In contrast, Au nanoclusters do not burrow into Ni surfaces; embedded clusters resurface to either form an extra layer on the surface or alloy with the topmost substrate layer.