Industrial & Engineering Chemistry Research, Vol.57, No.43, 14837-14845, 2018
Investigation of Possible Formation of Au@M (M = Cu, Ir, Pt, and Rh) Core-Shell Nanoclusters in a Condensation-Coalescence Process Using Molecular Dynamics Simulations
In this work, the possible formation of Au@Pt, Au@Cu, Au@Rh, and Au@Ir clusters during the vapor condensation-coalescence process has been investigated by inserting icosahedral gold nanocluster into copper, platinum, rhodium, and iridium vapor environments. We have studied some properties of the created nanoclusters at different simulation times. Our results showed that the stability of the formed core-shell structures obeys the following order: pure Au > Au@Cu > Au@Rh > Au@Ir which means that the positioning of rhodium, iridium, and copper on the gold cluster is unfavorable. The Au@Pt cluster was also the most stable cluster. The results also showed that the Au@Pt and Au@Rh are not pure core-shell structures but they are (Au/Pt mixed)@Pt and (Au/Rh mixed)@Rh structures. The structural investigations also indicated that the initial icosahedral morphology of the gold cluster was disappeared whereas the formed core-shell nanoclusters had fcc-like and hcp-like morphologies. The thermal investigations showed that the nanoclusters become more spherical by increasing the temperature. The gold atoms also migrate to the cluster surface but the metal surface atoms diffuse to the inner cluster layers by increasing the temperature.