NO Reduction Reaction on Cu catalyst
Muhammad Rifqi Al Fauzan\(^{1,2}\), Thanh Ngoc Pham\(^1\), and Yoshitada Morikawa\(^1\)

\(^1\) Department of Precision Engineering, Graduate School of Engineering, Osaka University, 2-1, Yamadaoka, Suita, Osaka 565-0871, Japan
\(^2\) Department of Electrical Engineering and Informatics, Vocational College, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia

Abstract

The dissociation of NO on Cu(100) is studied by using density functional theory (DFT). By exploring the minimum energy pathway, we found that the dimer-mediated dissociation is preferable compared to the direct monomer dissociation. An upright (NO)\(_2\) is initially formed and transformed into an upright ONNO then into a flat-lying ONNO. Subsequently, the flat-lying ONNO reacts to form N\(_2\)O and O with a low effective activation energy of 0.41 eV. This energy barrier is smaller compared to those Cu(111) and Cu(211) surfaces, which were reported as 0.84 eV and 0.62 eV, respectively. The formation of N\(_2\)O on the surface is followed by two possible pathways, namely, N\(_2\)O desorption with a 0.21 eV energy barrier and N\(_2\) desorption to yield adsorbed O atom with a small activation energy barrier. Our result suggests that the formation of dimer intermediate is the key to the high reactivity of NO on Cu(100) surface.
We are interested in studying further regarding this reaction on the other Cu surfaces.

Keywords: NO reduction, Cu-based catalyst, DFT

Topic: PHYSICAL SCIENCES