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Keywords
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Pt nanoparticle, CeO2, Carbon-ceramic Electrode, Formic acid, Formaldehyde, Fuel cells
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Abstract
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In this work, the Pt-CeO2 nanoparticles are deposited on the carbon-ceramic to
produce CCE supported Pt-CeO2. The Pt-CeO2 nanoparticles were electrodeposited on the CCE surface
from an aqueous solution of 0.1M H2SO4 contaninig H2PtCl6. 6H2O and excess of CeO2 at (-0.3V) versus
the saturated calomel electrode at 25 0C. After, surface, structural, and electrochemical characterizations
of the Pt-CeO2/CCE, the electrocatalytic activity of Pt-CeO2/CCE towards the formic acid and
formaldehyde oxidation in 0.1 M H2SO4 solution was evaluated by cyclic voltammometric and
chronoamperometric measurements and the obtained results were compared with those obtained on the
platinum nanoparticles CCE electrodes. It was found that Pt-CeO2/CCE was catalytically more active than
platinum nanoparticles supported CCE electrodes and had satisfactory stability and reproducibility when
stored in ambient conditions or continues cycling. Finally, A mechanism for CeO2 proposed enhancement
of oxidation can also be described by the bifunctional mechanism, according to the bifunctional theory the
OHads species on metal oxide can transform CO-like poisioning species (COads)on Pt to CO2, releasing the
active sites on Pt for further electrochemical reaction.
CeO2 + H2O CeO2-OHads+ H+ + e-
CeO2-OHads + Pt-COads Pt + CeO2 + CO2 + H+ + e-
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