Abstract
The retardation of the hydrogen oxidation reaction which commences at about 0.7v (NHE) in sulfuric acid solution can be modified by the presence of formate ions. Steady‐state, potentiostatic measurements were made in formic acid and formic acid plus sulfuric acid solutions both in the presence and absence of hydrogen. The work showed that at potentials under 1.5v passivity was due to adsorbed anions rather than adsorbed oxygen atoms, Pt oxides, or free radicals formed by the oxidation of water. Pure formic acid solutions were not passivated below 1.5v; however, formate ion did retard hydrogen oxidation, but not as strongly as does sulfate ion. The oxidation of formic acid in solutions containing sulfuric acid was affected by adsorption of both sulfate and formate ions. The retardation of the net oxidation of hydrogen and formic acid in formic acid‐sulfuric acid mixtures was less than that of hydrogen in sulfuric acid. In the presence of derma‐sorbed oxygen, both formate and sulfate ions strongly retard the oxidation of added species. The effect of potential on reaction rate appears to depend on the particular organic species adsorbed and may reflect the potential of zero charge.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.