Elucidating the Complex Oxidation Behavior of Aqueous H3PO3 on Pt Electrodes via In Situ Tender X-ray Absorption Near-Edge Structure Spectroscopy at the P K-Edge
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22310%2F24%3A43930822" target="_blank" >RIV/60461373:22310/24:43930822 - isvavai.cz</a>
Result on the web
<a href="https://pubs.acs.org/doi/10.1021/jacs.3c12381" target="_blank" >https://pubs.acs.org/doi/10.1021/jacs.3c12381</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1021/jacs.3c12381" target="_blank" >10.1021/jacs.3c12381</a>
Alternative languages
Result language
angličtina
Original language name
Elucidating the Complex Oxidation Behavior of Aqueous H3PO3 on Pt Electrodes via In Situ Tender X-ray Absorption Near-Edge Structure Spectroscopy at the P K-Edge
Original language description
In situ tender X-ray absorption near-edge structure (XANES) spectroscopy at the P K-edge was utilized to investigate the oxidation mechanism of aqueous H3PO3 on Pt electrodes under various conditions relevant to high-temperature polymer electrolyte membrane fuel cell (HT-PEMFC) applications. XANES and electrochemical analysis were conducted under different tender X-ray irradiation doses, revealing that intense radiation induces the oxidation of aqueous H3PO3 via H2O yielding H3PO4 and H-2. A broadly applicable experimental procedure was successfully developed to suppress these undesirable radiation-induced effects, enabling a more accurate determination of the aqueous H3PO3 oxidation mechanism. In situ XANES studies of aqueous 5 mol dm(-3) H3PO3 on electrodes with varying Pt availability and surface roughness reveal that Pt catalyzes the oxidation of aqueous H3PO3 to H3PO4. This oxidation is enhanced upon applying a positive potential to the Pt electrode or raising the electrolyte temperature, the latter being corroborated by complementary ion-exchange chromatography measurements. Notably, all of these oxidation processes involve reactions with H2O, as further supported by XANES measurements of aqueous H3PO3 of different concentrations, showing a more pronounced oxidation in electrolytes with a higher H2O content. The significant role of water in the oxidation of H3PO3 to H3PO4 supports the reaction mechanisms proposed for various chemical processes observed in this work and provides valuable insights into potential strategies to mitigate Pt catalyst poisoning by H3PO3 during HT-PEMFC operation.
Czech name
—
Czech description
—
Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
—
OECD FORD branch
10405 - Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)
Result continuities
Project
<a href="/en/project/GF22-23668K" target="_blank" >GF22-23668K: Pt-based intermetallic alloy catalysts for improved performance of high-temperature PEM fuel cells with reduced Pt loading</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2024
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Journal of the American Chemical Society
ISSN
0002-7863
e-ISSN
1520-5126
Volume of the periodical
146
Issue of the periodical within the volume
11
Country of publishing house
US - UNITED STATES
Number of pages
14
Pages from-to
7386-7399
UT code for WoS article
001181875600001
EID of the result in the Scopus database
2-s2.0-85187329704