| Autor: |
Eugenia Tanasa, Florentina Iuliana Maxim, Tugce Erniyazov, Matei-Tom Iacob, Tomáš Skála, Liviu Cristian Tanase, Cătălin Ianăși, Cristina Moisescu, Cristina Miron, Ioan Ardelean, Vlad-Andrei Antohe, Eugenia Fagadar-Cosma, Serban N. Stamatin |
| Jazyk: |
angličtina |
| Rok vydání: |
2021 |
| Předmět: |
|
| Zdroj: |
Nanomaterials, Vol 11, Iss 5, p 1198 (2021) |
| Druh dokumentu: |
article |
| ISSN: |
2079-4991 |
| DOI: |
10.3390/nano11051198 |
| Popis: |
Polymer electrolyte membrane fuel cells require cheap and active electrocatalysts to drive the oxygen reduction reaction. Nitrogen-doped carbons have been extensively studied regarding their oxygen reduction reaction. The work at hand looks beyond the nitrogen chemistry and brings to light the role of oxygen. Nitrogen-doped nanocarbons were obtained by a radio-frequency plasma route at 0, 100, 250, and 350 W. The lateral size of the graphitic domain, determined from Raman spectroscopy, showed that the nitrogen plasma treatment decreased the crystallite size. Synchrotron radiation photoelectron spectroscopy showed a similar nitrogen chemistry, albeit the nitrogen concentration increased with the plasma power. Lateral crystallite size and several nitrogen moieties were plotted against the onset potential determined from oxygen reduction reaction curves. There was no correlation between the electrochemical activity and the sample structure, as determine from Raman and synchrotron radiation photoelectron spectroscopy. Near-edge X-ray absorption fine structure (NEXAFS) was performed to unravel the carbon and nitrogen local structure. A difference analysis of the NEXAFS spectra showed that the oxygen surrounding the pyridinic nitrogen was critical in achieving high onset potentials. The work shows that there were more factors at play, other than carbon organization and nitrogen chemistry. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
|
