Interaction of water molecules with bare and deuterated polycrystalline diamond surface studied by high resolution electron energy loss and X-ray photoelectron spectroscopies

Water exposure onto a deuterated surface, on the other hand, does not result in the appearance of the C-OH vibrational peaks but only to an increase of the C-H vibrational HR-EELS mode along side with the appearance of a weaker XPS O (1) peak, as compared to the same experiment, performed on the bare surface. 300 °C anneal significantly diminishes surface oxygen concentration, as monitored by XPS. We associate these results with H2O decomposition reactions and also with molecular adsorption on deuterated diamond surfaces. Annealing of the water exposed deuterated diamond surface, results in a pronounced decrease and disappearance of the O (1s) XPS peak at a temperature of ~ 800 °C.