Effects of Loading and Nafion Content on the Activity and Stability of Iridium Oxygen Evolution Reaction Catalysts

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F25%3A10510606" target="_blank" >RIV/00216208:11320/25:10510606 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=iPXQ2wLblr" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=iPXQ2wLblr</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1149/1945-7111/ae1168" target="_blank" >10.1149/1945-7111/ae1168</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Effects of Loading and Nafion Content on the Activity and Stability of Iridium Oxygen Evolution Reaction Catalysts

Popis výsledku v původním jazyce

Iridium (Ir) is the benchmark catalyst for the oxygen evolution reaction (OER) in proton-exchange-membrane water electrolyzers, yet its scarcity demands rigorous, reproducible benchmarking in aqueous model systems. We systematically vary catalyst loading and Nafion ionomer content to probe how ink formulation governs the activity-stability trade-off for two Ir phases: metallic Ir and IrO2. OER activity and Ir dissolution are monitored simultaneously using online inductively coupled plasma mass spectrometry, and the catalyst-ionomer interface is characterized by electron microscopy and X-ray photoelectron spectroscopy. Our results show that catalyst loading has no effect on Ir dissolution, while ionomer content is the dominant and phase-dependent parameter: on metallic Ir, increasing Nafion lowers activity with no effect on dissolution, while for IrO2, it increases both activity and dissolution. These opposing trends are consistent with ionomer-induced changes in interfacial structure, oxidation state, particle dispersion, and accessible active area. Our study shows that ionomer content and catalyst phase must be carefully controlled and reported when benchmarking Ir-based OER catalysts, and provides practical guidelines to balance performance while minimizing precious-metal loss.

Název v anglickém jazyce

Effects of Loading and Nafion Content on the Activity and Stability of Iridium Oxygen Evolution Reaction Catalysts

Popis výsledku anglicky

Iridium (Ir) is the benchmark catalyst for the oxygen evolution reaction (OER) in proton-exchange-membrane water electrolyzers, yet its scarcity demands rigorous, reproducible benchmarking in aqueous model systems. We systematically vary catalyst loading and Nafion ionomer content to probe how ink formulation governs the activity-stability trade-off for two Ir phases: metallic Ir and IrO2. OER activity and Ir dissolution are monitored simultaneously using online inductively coupled plasma mass spectrometry, and the catalyst-ionomer interface is characterized by electron microscopy and X-ray photoelectron spectroscopy. Our results show that catalyst loading has no effect on Ir dissolution, while ionomer content is the dominant and phase-dependent parameter: on metallic Ir, increasing Nafion lowers activity with no effect on dissolution, while for IrO2, it increases both activity and dissolution. These opposing trends are consistent with ionomer-induced changes in interfacial structure, oxidation state, particle dispersion, and accessible active area. Our study shows that ionomer content and catalyst phase must be carefully controlled and reported when benchmarking Ir-based OER catalysts, and provides practical guidelines to balance performance while minimizing precious-metal loss.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10305 - Fluids and plasma physics (including surface physics)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of the Electrochemical Society

ISSN

0013-4651

e-ISSN

1945-7111

Svazek periodika

172

Číslo periodika v rámci svazku

10

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

9

Strana od-do

106506

Kód UT WoS článku

001598184600001

EID výsledku v databázi Scopus

2-s2.0-105019713273