title: Uncovering the Stabilization Mechanism in Bimetallic Ruthenium-Iridium Anodes for Proton Exchange Membrane Electrolyzers.
abstract: Proton exchange membrane (PEM) electrolyzers are attracting an increasing attention as a promising technology for the renewable electricity storage. In this work, near ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) is applied for in situ monitoring of the surface state of membrane electrode assemblies with RuO2 and bimetallic Ir0.7Ru0.3O2 anodes during water splitting. We demonstrate that Ir protects Ru from the formation of an unstable hydrous Ru(IV) oxide thereby rendering bimetallic Ru-Ir oxide electrodes with higher corrosion resistance. We further show that the water splitting occurs through a surface Ru(VIII) intermediate, and, contrary to common opinion, the presence of Ir does not hinder its formation.
authors.affiliation: Institut de Chimie et Procédés pour l'Energie, l'Environnement et la Santé, UMR 7515 du CNRS-UdS 25 Rue Becquerel, 67087 Strasbourg, France.
authors.forename: Viktoriia A
authors.initials: VA
authors.lastname: Saveleva
authors.affiliation: Institute of Engineering Thermodynamics, German Aerospace Center (DLR), Pfaffenwaldring 38-40, 70569 Stuttgart, Germany.
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.affiliation: Institut de Chimie et Procédés pour l'Energie, l'Environnement et la Santé, UMR 7515 du CNRS-UdS 25 Rue Becquerel, 67087 Strasbourg, France.
authors.forename: Wen
authors.initials: W
authors.lastname: Luo
authors.affiliation: Institut de Chimie et Procédés pour l'Energie, l'Environnement et la Santé, UMR 7515 du CNRS-UdS 25 Rue Becquerel, 67087 Strasbourg, France.
authors.forename: Spyridon
authors.initials: S
authors.lastname: Zafeiratos
authors.affiliation: Institut de Physique et Chimie des Matériaux de Strasbourg, 23 rue du Loess, BP 43, 67037 Strasbourg, France.
authors.forename: Corinne
authors.initials: C
authors.lastname: Ulhaq-Bouillet
authors.affiliation: Institute of Engineering Thermodynamics, German Aerospace Center (DLR), Pfaffenwaldring 38-40, 70569 Stuttgart, Germany.
authors.forename: Aldo S
authors.initials: AS
authors.lastname: Gago
authors.affiliation: Institute of Engineering Thermodynamics, German Aerospace Center (DLR), Pfaffenwaldring 38-40, 70569 Stuttgart, Germany.
authors.forename: K Andreas
authors.initials: KA
authors.lastname: Friedrich
authors.affiliation: Institut de Chimie et Procédés pour l'Energie, l'Environnement et la Santé, UMR 7515 du CNRS-UdS 25 Rue Becquerel, 67087 Strasbourg, France.
authors.forename: Elena R
authors.initials: ER
authors.lastname: Savinova