  Diamond displays outstanding chemical, physical, and tribological properties,
making it attractive for numerous applications ranging from biomedicine to
tribology. However, the reaction of the materials with molecules present in the
air, such as oxygen, hydrogen, and water, could significantly change the
electronic and tribological properties of the films. In this study, we
performed several density functional theory calculations to construct a
database for the adsorption energies and dissociation barriers of these
molecules on the most relevant diamond surfaces, including C(111), C(001), and
C(110). The adsorption configurations, reaction paths, activation energies, and
their influence on the structure of diamond surfaces are discussed. The results
indicate that there is a strong correlation between adsorption energy and
surface energy. Moreover, we found that the dissociation processes of oxygen
molecules on these diamond surfaces can significantly alter the surface
morphology and may affect the tribological properties of diamond films. These
findings can help to advance the development and optimization of devices and
antiwear coatings based on diamond.
