Publications by authors named "Thao T H Hoang"

Electrodeposition of CuAg alloy films from plating baths containing 3,5-diamino-1,2,4-triazole (DAT) as an inhibitor yields high surface area catalysts for the active and selective electroreduction of CO to multicarbon hydrocarbons and oxygenates. EXAFS shows the co-deposited alloy film to be homogeneously mixed. The alloy film containing 6% Ag exhibits the best CO electroreduction performance, with the Faradaic efficiency for CH and CHOH production reaching nearly 60 and 25%, respectively, at a cathode potential of just -0.

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The development of non-precious-metal (NPM) catalysts to replace the Pt alloys currently used in fuel cells to facilitate the oxygen reduction reaction (ORR) is a vital step in the widespread utilization of fuel cells. Currently, the ORR mechanism for NPM catalysts is not well understood, prohibiting the design and preparation of improved NPM catalysts. We conducted a kinetic isotope effect (KIE) study to identify the rate-determining step (RDS) of this intricate electrocatalytic reaction involving multiple proton-coupled electron transfer (PCET) processes.

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In situ electrochemical stress measurements are used to interrogate changes in oxide structure before and during the oxygen evolution reaction (OER) from Ir, Ni, Co, Au, and Pt electrodes in alkaline electrolyte. Stress evolution during potential cycling reports on changes in oxidation state and oxide forms. Hysteresis observed in the potential-dependent stress from Ir, Au, and Pt electrodes is associated with chemical irreversibility in electrode composition and roughness.

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Microcantilever stress measurements are examined to contrast and compare their attributes with those from in situ X-ray absorption spectroscopy to elucidate bonding dynamics during the oxygen reduction reaction (ORR) on a Pt catalyst. The present work explores multiple atomistic catalyst properties that notably include features of the Pt-Pt bonding and changes in bond strains that occur upon exposure to O2 in the electrochemical environment. The alteration of the Pt electronic and physical structures due to O2 exposure occurs over a wide potential range (1.

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