Water Adsorption on Native and Hydrogenated Diamond (001) Surfaces

Abstract

Understanding water interaction with diamond surfaces is fundamental for applications in tribology, device technology, and microelectronics operating in biological environments. In this paper, we provide a full microscopic description of the interaction of water with diamond (001) surfaces. We performed ab initio calculations within the framework of density functional theory including long-range van der Waals interactions. We considered both native and hydrogenated surfaces. We calculated the structure and the energetics for molecular and dissociative adsorption, and in the case of exothermic processes, we determined the energy barriers for dissociation. Our results allow prediction of the formation of water islands on native surfaces that grow along and perpendicularly to dimer rows. Moreover, they highlight the role played by the water coverage in determining the adsorption mode (physisorption or dissociation), suggesting an explanation for experimental results on similar Si(001) surfaces. Finally, we p...