Coverage and charge-state dependent adsorption of carbon monoxide on the zinc oxide (0001) surface

The adsorption of carbon monoxide (CO) on zinc oxide is important to a number of industrial processes. We report here density-functional calculations of CO binding geometries, adsorption energies, and vibrational frequencies on the polar Zn-terminated ZnO(0001) surface. Our results illuminate a surprising complexity in the adsorbate-surface and adsorbate-adsorbate interactions of this model surface science system, revealing that the nature of the bonding is highly dependent on CO coverage and surface oxidation state.