Elements science and technology project: Design of precious metal free catalyst for NO dissociation

Abstract

NO dissociation on Cu-based catalyst is investigated using density functional theory based calculations. NO dissociation on Cu-terminated Cu 2O(111) surface is comparable with its dissociation on Rh(111) which is characterized by a transition state lying below the reference level (surface and NOgas). This finding is associated to the modified electronic and geometric structure of the surface Cu atoms in comparison to the Cu atoms of Cu(111). The local density of states profile of the d orbital of the Cu atoms in Cu2O(111) shows that the states are shifted to the Fermi level region which explains the good adsorption and easy dissociation of NO. In Cu(111), the dissociation is accompanied by a large amount of activation barrier and NO desorption is more likely to happen. Coadsorbed N and O atoms are unstable on O-terminated Cu2O(111) and is due to the repulsive effect of the surface and subsurface O atoms. This work is made through the initiative of the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of the Japanese government through the Elements Science and Technology Project and is a collaboration among various research groups to realize functional materials that are free from precious and hazardous substances.