Acid-Base Interaction and Its Role in Alkane Dissociative Chemisorption on Oxide Surfaces

TitleAcid-Base Interaction and Its Role in Alkane Dissociative Chemisorption on Oxide Surfaces
Publication TypeJournal Article
Year of Publication2014
AuthorsChrétien S, Metiu H
JournalJ. Phys. Chem. C
Volume118
Pagination27336-27342
Abstract

We use density functional theory to examine methane dissociative adsorption on lanthana to produce H and CH$_3$ bonded to the surface. Previous work suggested that the binding energy of a Lewis base and a Lewis acid to an oxide exceeds by far the value expected from adding the binding energies of the same compounds chemisorbed alone. This rule suggests that the fragments (H and CH$_3$) formed by the dissociative adsorption of methane on an oxide will adsorb so that they could benefit from this strong acid–base interaction. To do this, one fragment must bind to oxygen and the other to a cation. Such a configuration should have lower energy than the one obtained by binding both fragments to oxygen, even though each fragment prefers to bind to oxygen when it binds alone. We suggest that this behavior is encountered in most systems.

DOI10.1021/jp507207b
Grant: 
MRI R2 (CNS-0960316), CSC, MRL (DMR-1121053)