Atomic‐Mesoscale Synergy in Amorphous Iridium Oxide Catalysts for Proton Exchange Membrane Water Electrolysis
Year: 2026
Type: article
Abstract: ABSTRACT Amorphous iridium oxide (IrO x ) is among the most active Ir‐based catalysts for the acidic oxygen evolution reaction (OER), yet its stability is severely limited because lattice‐oxygen participation often triggers irreversible oxygen loss that leads to iridium dissolution and structural degradation. Here, we present a surfactant‐directed synthesis of mesoporous IrO x electrocatalysts featuring a hollandite‐type local structure. This unique structure creates an atomic‐mesoscale synergy that enhances OER activity without sacrificing stability and improves high‐current‐density performance. At the atomic level, the hollandite‐type local structure promotes high OER activity and corrosion resistance. In situ spectroscopic and isotopic labeling experiments reveal a reversible cycle of lattice oxygen loss and reformation during OER. This process enables the flexible iridium local structure to transition between an initial six‐coordinate state and a low‐coordinated active state. At the mesoscale, an interconnected porous network ensures efficient mass transport and maximizes active‐site accessibility. As a result, this mesoporous electrocatalyst achieves a low cell voltage (1.75 V @ 2 A cm −2 ) and excellent stability for more than 2000 h (@ 2 A cm −2 ) in proton exchange membrane water electrolysis (PEMWE).
DOI: 10.1002/anie.5206101
Institutions: Jilin University, State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, State Key Laboratory of Catalysis, Northeastern University, Key Laboratory of Automobile Materials, Ministry of Education, Jilin University
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: bronze
Funders: Salt Science Research Foundation, National Natural Science Foundation of China, Chinese Academy of Sciences, People's Government of Jilin Province, Jilin University, Dalian Institute of Chemical Physics, Young Scientists Fund, Fundamental Research Funds for the Central Universities, Shanghai Advanced Research Institute, Chinese Academy of Sciences
OpenAlex ID: W7130517857