It was recalled that Cu/ZnO heterogeneous systems were used to catalyze CO2 hydrogenation to methanol, but questions remained concerning the nature of the active site and the role of Cu-ZnO interactions in the catalyst performance. The way in which ZnO surfaces supported Cu clusters and stabilized their active sites was a key factor in maintaining catalyst activity. Processes such as sintering, alloying and encapsulation could play an important role in the activity of the catalyst but were difficult to model directly with density functional theory. Here, the development of charge-optimized many-body potentials for modelling the Cu/ZnO system was reported. This potential was then used in conjugation with the dimer method, which used the first derivative of the potential energy and the initial state of the transition to find saddle points, to examine the migration barriers of Cu adatoms on Cu and ZnO surfaces. These findings were checked against the results of density functional theory calculations and published experimental data.

Atomistic Simulations of the Adsorption and Migration Barriers of Cu Adatoms on ZnO Surfaces using COMB Potentials. Cheng, Y.T., Shan, T.R., Devine, B., Lee, D., Liang, T., Hinojosa, B.B., Phillpot, S.R., Asthagiri, A., Sinnott, S.B.: Surface Science, 2012, 606[15-16], 1280-8