jp5b07206_si_001.pdf (732.6 kB)
Download fileSecond Order Dependence on the Surface Fraction of Pt in PtRuadatom of the Oxidation of 2‑PrOH in Base
journal contribution
posted on 2015-12-10, 00:00 authored by Matthew
E. P. Markiewicz, Steven H. BergensThe electrooxidation of 2-PrOH
in alkaline electrolyte is
studied over a series of Pt-Ru adatom catalysts with controlled surface
compositions as a function of potential and temperature. Multivariable
analysis is used to determine both kinetic and thermodynamic parameters
of interest. PtRu surfaces are found to be more active at low potentials
than either Pt or Ru alone. At moderate overpotentials, Pt is the
most active catalyst due to a surface blocking effect by Ru. A clear
second order dependence on the surface fraction of Pt is determined,
and a kinetic isotope effect suggest that both CH(D) and OH(D)
bonds are broken before or during the rate-determining step for
the electro-dehydrogenation of 2-propanol to acetone. Possible mechanisms
that account for these observations are discussed.