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  • Insights into how the aqueous environment influences the kinetics and mechanisms of heterogeneously-catalyzed COH* and CH 3 OH* dehydrogenation reactions on Pt(111)
Title: Insights into how the aqueous environment influences the kinetics and mechanisms of heterogeneously-catalyzed COH* and CH 3 OH* dehydrogenation reactions on Pt(111)
Water influences catalytic reactions in multiple ways, including energetic and mechanistic effects. While simulations have provided significant insight into the roles that H 2 O molecules play in aqueous-phase heterogeneous catalysis, questions still remain as to the extent to which H 2 O structures influence catalytic mechanisms. Specifically, influences of the configurational variability in the water structures at the catalyst interface are yet to be understood. Configurational variability is challenging to capture, as it requires multiscale approaches. Herein, we apply a multiscale sampling approach to calculate reaction thermodynamics and kinetics for COH* dehydrogenation to CO* and CH 3 OH* dehydrogenation to CH 2 OH* on Pt(111) catalysts under liquid H 2 O. We explore various pathways for these dehydrogenation reactions that could influence the overall mechanism of methanol decomposition by including participation of H 2 O structures both energetically and mechanistically. We find that the liquid H 2 O environment significantly influences the mechanism of COH* dehydrogenation to CO* but leaves the mechanism of CH 3 OH* dehydrogenation to CH 2 OH* largely unaltered.  more » « less
Award ID(s):
1725573
PAR ID:
10111158
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Physical Chemistry Chemical Physics
Volume:
21
Issue:
19
ISSN:
1463-9076
Page Range / eLocation ID:
9895 to 9904
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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