Dinitrosyl formation as an intermediate stage of the reduction of NO in the presence of MoO_3

摘要

We present first-principles calculations in the framework of density-functional theory and the pseudopotential approach, aiming to model the intermediate stages of the reduction of NO in the presence of MoO_3(010). In particular, we study the formation of dinitrosyl, which proves to be an important intermediate stage in the catalytic reductin. We find that the replacement of an oxygen of MoO_3 by NO is energetically favorable, and that the system lowers further its energy by the formation of (NO)_2. Moreover, the geometry and charge distribution for the adsorbed dinitrosyl indicates a metal-oxide mediated coupling between the two nitrogen and the two oxygen atoms. We discuss the mechanisms for the dinitrosyl formation and the role of the oxide in the reaction.