IrW nanochannel support enabling ultrastable electrocatalytic oxygen evolution at 2 A cm<sup>-2</sup> in acidic media.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 34112770.
- Also identified by DOI 10.1038/s41467-021-23907-1 and PMC identifier 8192761.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
A grand challenge for proton exchange membrane electrolyzers is the rational design of oxygen evolution reaction electrocatalysts to balance activity and stability. Here, we report a support-stabilized catalyst, the activated ~200 nm-depth IrW nanochannel that achieves the current density of 2 A cm<sup>-2</sup> at an overpotential of only ~497 mV and maintains ultrastable gas evolution at 100 mA cm<sup>-2</sup> at least 800 h with a negligible degradation rate of ~4 μV h<sup>-1</sup>. Structure analyses combined with theoretical calculations indicate that the IrW support alters the charge distribution of surface (IrO<sub>2</sub>)<sub>n</sub> clusters and effectively confines the cluster size within 4 (n≤4). Such support-stabilizing effect prevents the surface Ir from agglomeration and retains a thin layer of electrocatalytically active IrO<sub>2</sub> clusters on surface, realizing a win-win strategy for ultrahigh OER activity and stability. This work would open up an opportunity for engineering suitable catalysts for robust proton exchange membrane-based electrolyzers.