Journal article · Preprint article
Highly Active Nanoperovskite Catalysts for Oxygen Evolution Reaction: Insights into Activity and Stability of Ba0.5Sr0.5Co0.8Fe0.2O2+δ and PrBaCo2O5+δ
Paul Scherrer Institute1
Swiss Federal Laboratories for Materials Science and Technology (Empa)2
Department of Energy Conversion and Storage, Technical University of Denmark3
Atomic Scale Materials Modelling, Department of Energy Conversion and Storage, Technical University of Denmark4
Proton Energy Systems, Inc.5
Swiss Federal Institute of Technology Lausanne6
Swiss Federal Institute of Technology Zurich7
It is shown that producing PrBaCo2O5+δ and Ba0.5Sr0.5Co0.8Fe0.2O2+δ nanoparticle by a scalable synthesis method leads to high mass activities for the oxygen evolution reaction (OER) with outstanding improvements by 10× and 50×, respectively, compared to those prepared via the state‐of‐the‐art synthesis method.
Here, detailed comparisons at both laboratory and industrial scales show that Ba0.5Sr0.5Co0.8Fe0.2O2+δ appears to be the most active and stable perovskite catalyst under alkaline conditions, while PrBaCo2O5+δ reveals thermodynamic instability described by the density‐functional theory based Pourbaix diagrams highlighting cation dissolution under OER conditions.
Operando X‐ray absorption spectroscopy is used in parallel to monitor electronic and structural changes of the catalysts during OER. The exceptional BSCF functional stability can be correlated to its thermodynamic meta‐stability under OER conditions as highlighted by Pourbaix diagram analysis. BSCF is able to dynamically self‐reconstruct its surface, leading to formation of Co‐based oxy(hydroxide) layers while retaining its structural stability.
Differently, PBCO demonstrates a high initial OER activity while it undergoes a degradation process considering its thermodynamic instability under OER conditions as anticipated by its Pourbaix diagram. Overall, this work demonstrates a synergetic approach of using both experimental and theoretical studies to understand the behavior of perovskite catalysts.
Language: | English |
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Year: | 2018 |
Pages: | 1804355 |
ISSN: | 16163028 and 1616301x |
Types: | Journal article and Preprint article |
DOI: | 10.1002/adfm.201804355 |
ORCIDs: | Castelli, Ivano Eligio and 0000-0002-6052-0150 |