Modeling cobalt-nitrogen compounds as catalysts for dissociation of H2O.

Abstract

It has been shown experimentally that cobalt bonded to a nitrogen-doped graphene sheet can catalyze H removal from H2O. Density functional theory has been employed to obtain the minimum energy structure of H2O bonded to the cobalt-nitrogen graphene structure. The bond dissociation energy to remove an H atom from this structure was calculated to be 0.3eV, which compared with the calculated value of 4.2eV for the free H2O molecule, indicates this material can catalyze H2O dissociation. The agreement of the prediction of the theoretical model with the experimental observation lends support for the approach based on using bond dissociation energies. The model has been employed to show that a simpler structure, CN-Co, perhaps easier to synthesize, can also be an effective catalyst for the production of H from H2O.