TY - JOUR
T1 - Surface-Templated Assembly of Molecular Methanol on the Thin Film "29" Cu(111) Surface Oxide
AU - Therrien, Andrew J.
AU - Hensley, Alyssa J.R.
AU - Hannagan, Ryan T.
AU - Schilling, Alex C.
AU - Marcinkowski, Matthew D.
AU - Larson, Amanda M.
AU - McEwen, Jean Sabin
AU - Sykes, E. Charles H.
N1 - Publisher Copyright:
Copyright © 2019 American Chemical Society.
PY - 2019/2/7
Y1 - 2019/2/7
N2 - Identifying and characterizing the atomic-scale interaction of methanol with oxidized Cu surfaces is of fundamental relevance to industrial reactions, such as methanol steam reforming and methanol synthesis. In this work, we examine the adsorption of methanol on the well-defined "29" Cu oxide surface, using a combination of experimental and theoretical techniques, and elucidate the atomic-scale interactions that lead to a unique spatial ordering of methanol on the oxide thin film. We determine that the methanol chain structures form first due to epitaxy with the underlying "29" oxide surface. Specifically, the geometry of the "29" oxide is such that there are spatially adjacent O ?- sites, in the form of O adatoms, and Cu ?+ species, within the Cu 2 O-like rings, which allow for methanol to simultaneously bond to the surface via an O methanol -Cu ?+ dative bond and an OH methanol -O ?- hydrogen bond. The methanol-oxide bond strength outweighs the strength of methanol-methanol hydrogen bonds on the "29" Cu oxide, unlike methanol assembly on bare coinage metal surfaces on which hydrogen bonding between adjacent molecules leads to ordered arrays. Weak, long-range interactions lead to the formation of chains of only even numbers of methanol molecules. Together, this work reveals that, unlike that on metal surfaces, the corrugation of the oxide surface drives methanol adsorption to preferred binding sites, preventing intermolecular hydrogen bonding and dictating the adsorption geometry.
AB - Identifying and characterizing the atomic-scale interaction of methanol with oxidized Cu surfaces is of fundamental relevance to industrial reactions, such as methanol steam reforming and methanol synthesis. In this work, we examine the adsorption of methanol on the well-defined "29" Cu oxide surface, using a combination of experimental and theoretical techniques, and elucidate the atomic-scale interactions that lead to a unique spatial ordering of methanol on the oxide thin film. We determine that the methanol chain structures form first due to epitaxy with the underlying "29" oxide surface. Specifically, the geometry of the "29" oxide is such that there are spatially adjacent O ?- sites, in the form of O adatoms, and Cu ?+ species, within the Cu 2 O-like rings, which allow for methanol to simultaneously bond to the surface via an O methanol -Cu ?+ dative bond and an OH methanol -O ?- hydrogen bond. The methanol-oxide bond strength outweighs the strength of methanol-methanol hydrogen bonds on the "29" Cu oxide, unlike methanol assembly on bare coinage metal surfaces on which hydrogen bonding between adjacent molecules leads to ordered arrays. Weak, long-range interactions lead to the formation of chains of only even numbers of methanol molecules. Together, this work reveals that, unlike that on metal surfaces, the corrugation of the oxide surface drives methanol adsorption to preferred binding sites, preventing intermolecular hydrogen bonding and dictating the adsorption geometry.
UR - http://www.scopus.com/inward/record.url?scp=85060636677&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85060636677&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcc.8b10284
DO - 10.1021/acs.jpcc.8b10284
M3 - Article
AN - SCOPUS:85060636677
SN - 1932-7447
VL - 123
SP - 2911
EP - 2921
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
IS - 5
ER -