title: Nanosized IrO(x)-Ir Catalyst with Relevant Activity for Anodes of Proton Exchange Membrane Electrolysis Produced by a Cost-Effective Procedure.
abstract: We have developed a highly active nanostructured iridium catalyst for anodes of proton exchange membrane (PEM) electrolysis. Clusters of nanosized crystallites are obtained by reducing surfactant-stabilized IrCl3 in water-free conditions. The catalyst shows a five-fold higher activity towards oxygen evolution reaction (OER) than commercial Ir-black. The improved kinetics of the catalyst are reflected in the high performance of the PEM electrolyzer (1 mg(Ir) cm(-2)), showing an unparalleled low overpotential and negligible degradation. Our results demonstrate that this enhancement cannot be only attributed to increased surface area, but rather to the ligand effect and low coordinate sites resulting in a high turnover frequency (TOF). The catalyst developed herein sets a benchmark and a strategy for the development of ultra-low loading catalyst layers for PEM electrolysis.
authors.affiliation: Institute of Engineering Thermodynamics, German Aerospace Center (DLR), Pfaffenwaldring 38-40, 70569 Stuttgart (Germany).
authors.forename: Philipp
authors.initials: P
authors.lastname: Lettenmeier
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: Group of Electron Microscopy of Materials Science, Central Facility for Electron Microscopy, University of Ulm, 89081 Ulm (Germany).
authors.forename: Ute
authors.initials: U
authors.lastname: Golla-Schindler
authors.affiliation: Institute of Engineering Thermodynamics, German Aerospace Center (DLR), Pfaffenwaldring 38-40, 70569 Stuttgart (Germany).
authors.forename: Pawel
authors.initials: P
authors.lastname: Gazdzicki
authors.affiliation: Institute of Engineering Thermodynamics, German Aerospace Center (DLR), Pfaffenwaldring 38-40, 70569 Stuttgart (Germany).
authors.forename: Natalia A
authors.initials: NA
authors.lastname: Cañas
authors.affiliation: University of Applied Sciences Esslingen, Department of Basic Science, Kanalstrasse 33, 73728 Esslingen (Germany).
authors.forename: Michael
authors.initials: M
authors.lastname: Handl
authors.affiliation: University of Applied Sciences Esslingen, Department of Basic Science, Kanalstrasse 33, 73728 Esslingen (Germany).
authors.forename: Renate
authors.initials: R
authors.lastname: Hiesgen
authors.affiliation: Institute of Engineering Thermodynamics, German Aerospace Center (DLR), Pfaffenwaldring 38-40, 70569 Stuttgart (Germany).
authors.forename: Seyed S
authors.initials: SS
authors.lastname: Hosseiny
authors.affiliation: Institute of Engineering Thermodynamics, German Aerospace Center (DLR), Pfaffenwaldring 38-40, 70569 Stuttgart (Germany). aldo.gago@dlr.de.
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: Kaspar A
authors.initials: KA
authors.lastname: Friedrich
keywords: electrocatalysts; iridium; oxygen evolution reactions; proton exchange membranes