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Title: Selectivity for ethanol partial oxidation: the unique chemistry of single-atom alloy catalysts on Au, Ag, and Cu(111)
Recently, we found that the atomic ensemble effect is the dominant effect influencing catalysis on surfaces alloyed with strong- and weak-binding elements, determining the activity and selectivity of many reactions on the alloy surface. In this study we design single-atom alloys that possess unique dehydrogenation selectivity towards ethanol (EtOH) partial oxidation, using knowledge of the alloying effects from density functional theory calculations. We found that doping of a strong-binding single-atom element ( e.g. , Ir, Pd, Pt, and Rh) into weak-binding inert close-packed substrates ( e.g. , Au, Ag, and Cu) leads to a highly active and selective initial dehydrogenation at the α-C–H site of adsorbed EtOH. We show that many of these stable single-atom alloy surfaces not only have tunable hydrogen binding, which allows for facile hydrogen desorption, but are also resistant to carbon coking. More importantly, we show that a rational design of the ensemble geometry can tune the selectivity of a catalytic reaction.  more » « less
Award ID(s):
1764230
NSF-PAR ID:
10146075
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Journal of Materials Chemistry A
Volume:
7
Issue:
41
ISSN:
2050-7488
Page Range / eLocation ID:
23868 to 23877
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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