TU Darmstadt / ULB / TUbiblio

Beyond the top of the volcano? – A unified approach to electrocatalytic oxygen reduction and oxygen evolution

Busch, Michael and Halck, Niels B. and Kramm, Ulrike I. and Siahrostami, Samira and Krtil, Petr and Rossmeisl, Jan (2016):
Beyond the top of the volcano? – A unified approach to electrocatalytic oxygen reduction and oxygen evolution.
In: Nano Energy, Elsevier Science Publishing, pp. 126-135, 29, ISSN 22112855, [Online-Edition: https://doi.org/10.1016/j.nanoen.2016.04.011],
[Article]

Abstract

We study the oxygen reduction (ORR) and the oxygen evolution reaction (OER) and based on previous obtained mechanistic insight we provide a unified general analysis of the two reactions simultaneously. The analysis shows that control over at least two independent binding energies is required to obtain a reversible perfect catalyst for both ORR and OER. Often only the reactivity of the surface is changed by changing from one material to another and all binding energies scale with the reactivity. We investigate the limitation in efficiency imposed by these linear scaling relations. This analysis gives rise to a double volcano for ORR and OER, with a region in between, forbidden by the scaling relations. The reversible perfect catalyst for both ORR and OER would fall into this “forbidden region”. Previously, we have found that hydrogen acceptor functionality on oxide surfaces can improve the catalytic performance for OER beyond the limitations originating from the scaling relations. We use this concept to search for promising combinations of binding sites and hydrogen donor/acceptor sites available in transition metal doped graphene, which can act as a catalyst for ORR and OER. We find that MnN4-site embedded in graphene by itself or combined with a COOH is a promising combination for a great combined ORR/OER catalyst.

Item Type: Article
Erschienen: 2016
Creators: Busch, Michael and Halck, Niels B. and Kramm, Ulrike I. and Siahrostami, Samira and Krtil, Petr and Rossmeisl, Jan
Title: Beyond the top of the volcano? – A unified approach to electrocatalytic oxygen reduction and oxygen evolution
Language: English
Abstract:

We study the oxygen reduction (ORR) and the oxygen evolution reaction (OER) and based on previous obtained mechanistic insight we provide a unified general analysis of the two reactions simultaneously. The analysis shows that control over at least two independent binding energies is required to obtain a reversible perfect catalyst for both ORR and OER. Often only the reactivity of the surface is changed by changing from one material to another and all binding energies scale with the reactivity. We investigate the limitation in efficiency imposed by these linear scaling relations. This analysis gives rise to a double volcano for ORR and OER, with a region in between, forbidden by the scaling relations. The reversible perfect catalyst for both ORR and OER would fall into this “forbidden region”. Previously, we have found that hydrogen acceptor functionality on oxide surfaces can improve the catalytic performance for OER beyond the limitations originating from the scaling relations. We use this concept to search for promising combinations of binding sites and hydrogen donor/acceptor sites available in transition metal doped graphene, which can act as a catalyst for ORR and OER. We find that MnN4-site embedded in graphene by itself or combined with a COOH is a promising combination for a great combined ORR/OER catalyst.

Journal or Publication Title: Nano Energy
Volume: 29
Publisher: Elsevier Science Publishing
Uncontrolled Keywords: Electrocatalysis, Oxygen reduction, Oxygen Evolution, Volcano, Density functional theory
Divisions: 11 Department of Materials and Earth Sciences > Material Science > Catalysts and Electrocatalysts
07 Department of Chemistry
11 Department of Materials and Earth Sciences > Material Science
11 Department of Materials and Earth Sciences
Date Deposited: 17 Aug 2017 11:00
Official URL: https://doi.org/10.1016/j.nanoen.2016.04.011
Identification Number: doi:10.1016/j.nanoen.2016.04.011
Funders: The project was supported by the Carlsberg foundation grant CF15-0165., UIK acknowledges financial support by the DFG (GSC 1070).
Export:

Optionen (nur für Redakteure)

View Item View Item