Oxygen reduction on nanocrystalline ruthenia – local structure effects

0437180 - ÚFCH JH 2016 RIV GB eng J - Článek v odborném periodiku
Abbott, D. F. - Mukerjee, S. - Petrykin, Valery - Bastl, Zdeněk - Halck, N. B. - Rossmeisl, J. - Krtil, Petr
Oxygen reduction on nanocrystalline ruthenia – local structure effects.
RSC Advances. Roč. 5, č. 2 (2015), s. 1235-1243. E-ISSN 2046-2069
Grant CEP: GA ČR(CZ) GAP108/12/1889
GRANT EU: European Commission(XE) 214936 - ELCAT
Institucionální podpora: RVO:61388955
Klíčová slova: RuO2-doped Ni/Co3O4 electrodes * evolution reaction * electrocatalysis
Kód oboru RIV: CG - Elektrochemie
Impakt faktor: 3.289, rok: 2015

Nanocrystalline ruthenium dioxide and doped ruthenia of the composition Ru1−xMxO2 (M = Co, Ni, Zn) with 0 ≤ x ≤ 0.2 were prepared by the spray-freezing freeze-drying technique. The oxygen reduction activity and selectivity of the prepared materials were evaluated in alkaline media using the RRDE methodology. All ruthenium based oxides show a strong preference for a 2-electron oxygen reduction pathway at low overpotentials. The catalysts' selectivity shifts towards the 4-electron reduction pathway at high overpotentials (i.e. at potentials below 0.4 V vs. RHE). This trend is particularly noticeable on non-doped and Zn-doped catalysts; the materials containing Ni and Co produce a significant fraction of hydrogen peroxide even at high overpotentials. The suppression of the 4-electron reduction pathway on Ni and Co-doped catalysts can be accounted for by the presence of the Ni and Co cations in the cus binding sites as shown by the DFT-based analyses on non-doped and doped catalysts.
Trvalý link: http://hdl.handle.net/11104/0240744