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Updated: Jan 15, 2026
On the Preparation and Testing of Fuel Cell Catalysts Using the Thin Film Rotating Disk Electrode Method
Published on: March 16, 2018
Linking electrocatalytic turnover to elementary step rates in hydrocarbon fuel oxidation
Alexander J Zielinski1, Christine Lucky2, Marcel Schreier3,4
1Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA.
None:
Maximizing steady-state turnover rates is a central goal in electrocatalysis research, but improving one reaction step often impedes others. Navigating these trade-offs requires methods that systematically reveal how a single parameter change affects all key steps of a reaction mechanism. Here, we use electrochemical mass spectrometry to determine the potential-dependent rates of each principal step in propane oxidation on Pt and directly relate them to the steady-state turnover rate. Our analysis reveals that low steady-state activity arises from a mismatch between the optimal potentials for adsorption, conversion, and *CO oxidation. By applying alternating potentials to individually optimize adsorption and oxidation, we overcome this limitation and achieve rates exceeding those under constant-potential operation. This step-resolved approach clarifies how individual processes interact to govern overall activity and provides a framework for the rational design of electrocatalysts carrying out complex reactions at steady-state.
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