Water Ordering On Aluminum Oxide Surfaces

Aluminum oxide is a useful material in engineering applications such as environmental remediation for the removal of heavy metals from water, and advanced materials such as ceramics and coatings. The structure of the clean and hydroxylated aluminum oxide (11-20) surface has been studied using density functional theory. The lowest-energy surface structure has been found to be the stoichiometric surface, which is in stark contrast to the results on other aluminum oxide surfaces (e.g., (0001), (1-102)). The hydroxylated surfaces have also been studied with density functional theory, where four water molecules have been dissociated per unit cell. The results show that the stoichiometric surface termination is favored in aqueous environments as well.