Single particle electrochemical oxidation of polyvinylpyrrolidone-capped silver nanospheres, nanocubes, and nanoplates in potassium nitrate and potassium hydroxide solutions
- Single particle electrochemical oxidation of polyvinylpyrrolidone-capped silver nanoparticles at a microdisk electrode is investigated as a function of particle shape (spheres, cubes, and plates) in potassium nitrate and potassium hydroxide solutions. In potassium nitrate, extreme anodic potentials (≥1500 mV vs Ag/AgCl (3 M KCl)) are necessary to achieve oxidation, while lower anodic potentials are required in potassium hydroxide (≥900 mV vs Ag/AgCl (saturated KCl)). Upon oxidation, silver oxide is formed, readily catalyzing water oxidation, producing a spike-step current response. The spike duration for each particle is used to probe effects of particle shape on the oxidation mechanism, and is substantially shorter in nitrate solution at the large overpotentials than in hydroxide solution. The integration of current spikes indicates oxidation to a mixed-valence complex. In both electrolytes, the rate of silver oxidation strongly depends on silver content of the nanoparticles, rather than the shape-dependent variable-surface area. The step height, which reflects rate of water oxidation, also tracks the silver content more so than shape. The reactivity of less-protected citrate-capped particles toward silver oxidation is also compared with that of the polymer-capped particles under these anodic conditions in the nitrate and hydroxide solutions.
Author: | Jazlynn C. SikesORCiDGND, Isabelle I. NiyonshutiORCiDGND, Kannasoot KanokkanchanaORCiDGND, Jingyi ChenORCiDGND, Kristina TschulikORCiDGND, Ingrid FritschORCiDGND |
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URN: | urn:nbn:de:hbz:294-89520 |
DOI: | https://doi.org/10.1149/1945-7111/ac63f3 |
Parent Title (English): | Journal of the electrochemical society |
Publisher: | IOP Publishing Limited |
Place of publication: | Bristol, Vereinigtes Königreich |
Document Type: | Article |
Language: | English |
Date of Publication (online): | 2022/05/18 |
Date of first Publication: | 2022/05/09 |
Publishing Institution: | Ruhr-Universität Bochum, Universitätsbibliothek |
Tag: | MITICAT, Projekt ID 94924 |
Volume: | 169 |
Issue: | 5 |
Pagenumber: | 13 |
Note: | Projekt MITICAT, Project ID: 949724 |
Relation (DC): | info:eu-repo/grantAgreement/EC/H2020/949724 |
Institutes/Facilities: | Lehrstuhl für Analytische Chemie II, Elektrochemie und Nanoskalige Materialien |
Dewey Decimal Classification: | Naturwissenschaften und Mathematik / Chemie, Kristallographie, Mineralogie |
OpenAIRE: | OpenAIRE |
faculties: | Fakultät für Chemie und Biochemie |
Licence (English): | Creative Commons - CC BY 4.0 - Attribution 4.0 International |