Tunnel-structured IrOx unlocks catalytic efficiency in proton exchange membrane water electrolyzers

Abstract Proton exchange membrane water electrolyzers face challenges due to high iridium loading and sluggish oxygen evolution reaction kinetics when using conventional rutile-structured iridium oxide nanocatalysts. Here we find that iridium oxide catalysts with a specific tunnel-type crystal struc...

Full description

Saved in:
Bibliographic Details
Main Authors: Mingcheng Zhang, Wei An, Qianqian Liu, Yuzhu Jiang, Xiao Zhao, Hui Chen, Yongcun Zou, Xiao Liang, Xiaoxin Zou
Format: Article
Language:English
Published: Nature Portfolio 2025-08-01
Series:Nature Communications
Online Access:https://doi.org/10.1038/s41467-025-62861-0
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849332193151680512
author Mingcheng Zhang
Wei An
Qianqian Liu
Yuzhu Jiang
Xiao Zhao
Hui Chen
Yongcun Zou
Xiao Liang
Xiaoxin Zou
author_facet Mingcheng Zhang
Wei An
Qianqian Liu
Yuzhu Jiang
Xiao Zhao
Hui Chen
Yongcun Zou
Xiao Liang
Xiaoxin Zou
author_sort Mingcheng Zhang
collection DOAJ
description Abstract Proton exchange membrane water electrolyzers face challenges due to high iridium loading and sluggish oxygen evolution reaction kinetics when using conventional rutile-structured iridium oxide nanocatalysts. Here we find that iridium oxide catalysts with a specific tunnel-type crystal structure exhibit highly localized reactivity, where regions at tunnel mouths drive oxygen evolution far more efficiently than tunnel-wall regions. The intrinsic activity of tunnel mouths is 25-fold higher than that of tunnel walls, with shorter nanorods achieving a better balance between active site exposure and electron/mass transport efficiency. When implemented in proton exchange membrane water electrolyzers, this engineered catalyst achieves notable performance at low iridium loading (0.28 mgIr cm−2), delivering over 2.0 A cm−2 at 1.8 V (80 °C) and operating stably for 1800 h—notably outperforming conventional catalysts. Our work identifies catalytic hotspots in tunnel-structured oxides and demonstrates their rational integration into high-performance, durable electrolyzer systems.
format Article
id doaj-art-e532dbaba29647f6bdb6a38538564eca
institution Kabale University
issn 2041-1723
language English
publishDate 2025-08-01
publisher Nature Portfolio
record_format Article
series Nature Communications
spelling doaj-art-e532dbaba29647f6bdb6a38538564eca2025-08-20T03:46:17ZengNature PortfolioNature Communications2041-17232025-08-0116111510.1038/s41467-025-62861-0Tunnel-structured IrOx unlocks catalytic efficiency in proton exchange membrane water electrolyzersMingcheng Zhang0Wei An1Qianqian Liu2Yuzhu Jiang3Xiao Zhao4Hui Chen5Yongcun Zou6Xiao Liang7Xiaoxin Zou8State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin UniversityState Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin UniversityState Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin UniversityState Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin UniversityKey Laboratory of Automobile Materials of MOE, School of Materials Science and Engineering, Jilin UniversityState Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin UniversityState Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin UniversityState Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin UniversityState Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin UniversityAbstract Proton exchange membrane water electrolyzers face challenges due to high iridium loading and sluggish oxygen evolution reaction kinetics when using conventional rutile-structured iridium oxide nanocatalysts. Here we find that iridium oxide catalysts with a specific tunnel-type crystal structure exhibit highly localized reactivity, where regions at tunnel mouths drive oxygen evolution far more efficiently than tunnel-wall regions. The intrinsic activity of tunnel mouths is 25-fold higher than that of tunnel walls, with shorter nanorods achieving a better balance between active site exposure and electron/mass transport efficiency. When implemented in proton exchange membrane water electrolyzers, this engineered catalyst achieves notable performance at low iridium loading (0.28 mgIr cm−2), delivering over 2.0 A cm−2 at 1.8 V (80 °C) and operating stably for 1800 h—notably outperforming conventional catalysts. Our work identifies catalytic hotspots in tunnel-structured oxides and demonstrates their rational integration into high-performance, durable electrolyzer systems.https://doi.org/10.1038/s41467-025-62861-0
spellingShingle Mingcheng Zhang
Wei An
Qianqian Liu
Yuzhu Jiang
Xiao Zhao
Hui Chen
Yongcun Zou
Xiao Liang
Xiaoxin Zou
Tunnel-structured IrOx unlocks catalytic efficiency in proton exchange membrane water electrolyzers
Nature Communications
title Tunnel-structured IrOx unlocks catalytic efficiency in proton exchange membrane water electrolyzers
title_full Tunnel-structured IrOx unlocks catalytic efficiency in proton exchange membrane water electrolyzers
title_fullStr Tunnel-structured IrOx unlocks catalytic efficiency in proton exchange membrane water electrolyzers
title_full_unstemmed Tunnel-structured IrOx unlocks catalytic efficiency in proton exchange membrane water electrolyzers
title_short Tunnel-structured IrOx unlocks catalytic efficiency in proton exchange membrane water electrolyzers
title_sort tunnel structured irox unlocks catalytic efficiency in proton exchange membrane water electrolyzers
url https://doi.org/10.1038/s41467-025-62861-0
work_keys_str_mv AT mingchengzhang tunnelstructurediroxunlockscatalyticefficiencyinprotonexchangemembranewaterelectrolyzers
AT weian tunnelstructurediroxunlockscatalyticefficiencyinprotonexchangemembranewaterelectrolyzers
AT qianqianliu tunnelstructurediroxunlockscatalyticefficiencyinprotonexchangemembranewaterelectrolyzers
AT yuzhujiang tunnelstructurediroxunlockscatalyticefficiencyinprotonexchangemembranewaterelectrolyzers
AT xiaozhao tunnelstructurediroxunlockscatalyticefficiencyinprotonexchangemembranewaterelectrolyzers
AT huichen tunnelstructurediroxunlockscatalyticefficiencyinprotonexchangemembranewaterelectrolyzers
AT yongcunzou tunnelstructurediroxunlockscatalyticefficiencyinprotonexchangemembranewaterelectrolyzers
AT xiaoliang tunnelstructurediroxunlockscatalyticefficiencyinprotonexchangemembranewaterelectrolyzers
AT xiaoxinzou tunnelstructurediroxunlockscatalyticefficiencyinprotonexchangemembranewaterelectrolyzers