Active and Stable Layered Alkali Iridates Efficiently Catalyze Oxygen Electroevolution in Low-Ir Proton-Exchange Membrane (PEM) Water Electrolyzers.

ABSTRACT: Developing catalysts with improved activity and stability compared to rutile IrO₂ or amorphous IrO_x remains a technical priority for advancing the oxygen evolution reaction (OER) in proton-exchange membrane water electrolyzers (PEMWEs). Here, we report structure-OER activity-stability relationships across a family of alkali cation-intercalated iridates, uncovering a structural evolution from hollandite to layered-type structures, characterized by the ratio of edge-sharing to corner-sharing connections of [IrO₆] octahedral motifs. In particular, Li-IrO_x and Cs-IrO_x demonstrate excellent PEMWE performance over a wide current range, pushing Ir demand to new lows. Both achieve a power-specific Ir demand of 0.06 g_I

SUBMITTER: Kang J 

PROVIDER: S-EPMC12703661 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature