Photoelectrocatalytic oxidation of As(III) over hematite photoanodes: A sensible indicator of the presence of highly reactive surface sites
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F18%3A73590228" target="_blank" >RIV/61989592:15310/18:73590228 - isvavai.cz</a>
Result on the web
<a href="https://www.sciencedirect.com/science/article/pii/S0013468618322199" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0013468618322199</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1016/j.electacta.2018.10.003" target="_blank" >10.1016/j.electacta.2018.10.003</a>
Alternative languages
Result language
angličtina
Original language name
Photoelectrocatalytic oxidation of As(III) over hematite photoanodes: A sensible indicator of the presence of highly reactive surface sites
Original language description
Hematite-based photoanodes were used for the photoelectrocatalysed batch oxidation of As(III) in water at pH 7 and 10. Tests were carried out at different As(III) initial concentrations, ranging from 150 mu g/L to 30 mg/L. With no pre-treatments, an initial inactive period of 40-50 min was always observed at the beginning of every test. This initial inactive period is completely removed by a surface modification of surface active sites induced by a pre-polarisation at 800 mV (vs. Ag/AgCl). The water splitting active sites related to the Fe(III)-Fe(IV) redox couple were proved to be not active towards As(III) oxidation. The modifications induced by the anodic prepolarisation were deeply studied: no evidence of the formation of surface highly oxidised iron sites (Fe(V) or Fe(VI)) and/or of highly reactive oxygen vacant sites emerges from XPS analysis. Rather, all collected characterisation data support the conclusion that more reactive terminal oxygen species are necessary for As(III) oxydation. The As(III) abatement reaction was modelled by two subsequent first order kinetics in As(III), independently from the initial As(III) concentration: this behaviour was explained suggesting that the highly reactive sites, being formed after prepolarisation, are gradually depleted during the reaction. As this reaction was proved to be very sensitive to the presence of highly reactive iron sites, its utilisation as a probe reaction to study hematite photoanodes is suggested.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10405 - Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)
Result continuities
Project
<a href="/en/project/EF15_003%2F0000416" target="_blank" >EF15_003/0000416: Advanced Hybrid Nanostructures for Renewable Energy Applications</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2018
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
ELECTROCHIMICA ACTA
ISSN
0013-4686
e-ISSN
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Volume of the periodical
292
Issue of the periodical within the volume
DEC
Country of publishing house
GB - UNITED KINGDOM
Number of pages
10
Pages from-to
828-837
UT code for WoS article
000449708500088
EID of the result in the Scopus database
2-s2.0-85056149197