Chemical Recognition of Active Oxygen Species on the Surface of Oxygen Evolution Reaction Electrocatalysts

• Published in: Angewandte Chemie International Edition Vol. 56; no. 30; pp. 8652 - 8656
• Main Authors: Yang, Chunzhen, Fontaine, Olivier, Tarascon, Jean‐Marie, Grimaud, Alexis
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 17-07-2017; John Wiley and Sons Inc
• Edition: International ed. in English
• Subjects: Biological evolution; Catalysis; Catalysts; Cations; Communication; Communications; deprotonation; Electrocatalysts; Hydrogen; Hydrogen bonds; Intermediates; Iron; isotopic effect; Nickel; nickel oxyhydroxide; Oxides; Oxygen; oxygen evolution reaction; Oxygen evolution reactions; pH effects; Probes; Transition metal oxides; oxygen evolution reaction; isotopic effect; nickel oxyhydroxide; deprotonation
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201701984

Owing to the transient nature of the intermediates formed during the oxygen evolution reaction (OER) on the surface of transition metal oxides, their nature remains largely elusive by the means of simple techniques. The use of chemical probes is proposed, which, owing to their specific affinities towards different oxygen species, unravel the role played by these species on the OER mechanism. For that, tetraalkylammonium (TAA) cations, previously known for their surfactant properties, are introduced, which interact with the active oxygen sites and modify the hydrogen bond network on the surface of OER catalysts. Combining chemical probes with isotopic and pH‐dependent measurements, it is further demonstrated that the introduction of iron into amorphous Ni oxyhydroxide films used as model catalysts deeply modifies the proton exchange properties, and therefore the OER mechanism and activity.
Introduction of iron into nickel oxyhydroxide amorphous films deeply modifies the interfacial proton diffusion properties, and tetraalkylammonium cations capture reactive oxygen species. These effects are related to the activity and mechanism of the oxygen evolution reaction. IHP/OHP=inner/outer Helmholtz plane.