Journal article
The Importance of Surface IrOx in Stabilizing RuO2 for Oxygen Evolution
The high precious metal loading and high overpotential of the oxygen evolution reaction (OER) prevents the widespread utilization of polymer electrolyte membrane (PEM) water electrolyzers. Herein we explore the OER activity and stability in acidic electrolyte of a combined IrOx/RuO2 system consisting of RuO2 thin films with sub-monolayer (1, 2 and 4 Å) amounts of IrOx deposited on top.
Operando extended X-ray absorption fine structure (EXAFS) on the Ir L-3 edge revealed a rutile type IrO2 structure with some Ir sites occupied by Ru, IrOx being at the surface of the RuO2 thin film. We monitor corrosion on IrOx/RuO2 thin films by combining electrochemical quartz crystal microbalance (EQCM) with inductively coupled mass spectrometry (ICP-MS).
We elucidate the importance of sub-monolayer surface IrOx in minimizing Ru dissolution. Our work shows that we can tune the surface properties of active OER catalysts such as RuO2, aiming to achieve higher electrocatalytic stability in PEM electrolyzers.
Language: | English |
---|---|
Publisher: | American Chemical Society (ACS) |
Year: | 2018 |
Pages: | 947-955 |
ISSN: | 15205207 and 15206106 |
Types: | Journal article |
DOI: | 10.1021/acs.jpcb.7b07047 |
ORCIDs: | Chorkendorff, Ib , Pedersen, Anders Filsøe , Stephens, Ifan E L , 0000-0002-6432-3015 and 0000-0001-7749-6567 |