Cluster‐Scale MoO x ‐IrO 2 Heterointerfaces Steer Dual‐Site Coupling and Interfacial Water Dynamics for Fast and Durable Oxygen Evolution
Year: 2026
Type: article
Abstract: ABSTRACT Proton exchange membrane water electrolyzers (PEMWEs) are central to renewable‐powered green hydrogen production. As the benchmark electrocatalyst for the oxygen evolution reaction (OER), conventional single‐phase IrO 2 is constrained by linear scaling relations among oxygenated intermediates, compounded by severe mass‐transport limitations and poorly regulated interfacial water structures. Here, we design a Turing‐type MoO x ‐IrO 2 heterostructure with strongly coupled cluster‐scale interfaces, which enables dual‐function Ir‐Mo synergy that breaks fundamental kinetic limitations and optimizes interfacial water structures. At the reaction pathway level, Brønsted‐acidic MoO x clusters promote water dissociation to generate reactive Mo─OH* intermediates, triggering radical coupling with adjacent Ir─O* species to form OOH* and thus circumventing the linear scaling relation. At the interfacial microenvironment level, MoO x reorganizes the rigid hydrogen‐bonding networks and increases the population of free H 2 O species, effectively alleviating concentration overpotentials under high‐current‐density operation. When integrated into a practical 25 cm 2 membrane electrode assembly, this catalyst delivers a PEMWE cell voltage of 1.71 V at 3 A cm −2 and an ultralow degradation rate of ∼9.5 µV h −1 over 1000 h, with a total platinum‐group‐metal loading of merely 0.5 mg cm −2 across both electrodes. Our dual‐modulation strategy establishes a transformative paradigm for developing low‐iridium and durable OER electrocatalysts toward practical green hydrogen production.
DOI: 10.1002/anie.3499419
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W7223470940