Platinum interlayers reduce charge transport barriers between amorphous Ir-oxide OER electrocatalysts and the porous transport layer

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F25%3A10510428" target="_blank" >RIV/00216208:11320/25:10510428 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=a3xJti-dCs" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=a3xJti-dCs</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.cej.2025.162887" target="_blank" >10.1016/j.cej.2025.162887</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Platinum interlayers reduce charge transport barriers between amorphous Ir-oxide OER electrocatalysts and the porous transport layer

Popis výsledku v původním jazyce

Significant research efforts are dedicated to reducing the iridium loading in proton-exchange membrane water electrolyzers. Recently, the focus shifted toward better understanding the interplay between the titanium porous transport layers (PTLs) and the Ir-oxide-based catalyst layers, where significant performance losses were observed for low-loaded anodes based on intrinsically highly active but poorly conductive amorphous IrOx. In the presented study, a gas-diffusion electrode half-cell setup is used to promote an understanding of the underlying phenomena leading to this low performance. The influence of the PTL platinization on the performance of realistic porous transport electrodes (PTEs) for the oxygen evolution reaction (OER) is investigated by gradually increasing the platinum layer thickness for PTEs based on amorphous and rutile Ir-oxide. Electrochemical measurements show a beneficial influence of platinization on the activity for amorphous, but not for rutile Iroxide. Impedance analysis corroborates the formation of a Schottky-type interface between the PTL and the amorphous IrOx catalyst layers, depending on the PTL&apos;s platinum layer thickness. We presume that this heterogeneous Schottky-type interface induces an additional voltage drop and influences the utilization of the catalyst layer, leading to increased overpotentials. The measurements were complemented by inductively coupled plasma mass spectrometry showing constant integral amounts of Ir dissolving from the catalyst layers during the OER, independent of the platinization. Transferring the obtained knowledge to single cells, the whole composite anode, including e.g. the interplay between PTL and catalyst layer, must be optimized in conjunction to achieve optimum OER performance and long-term stability.

Název v anglickém jazyce

Platinum interlayers reduce charge transport barriers between amorphous Ir-oxide OER electrocatalysts and the porous transport layer

Popis výsledku anglicky

Significant research efforts are dedicated to reducing the iridium loading in proton-exchange membrane water electrolyzers. Recently, the focus shifted toward better understanding the interplay between the titanium porous transport layers (PTLs) and the Ir-oxide-based catalyst layers, where significant performance losses were observed for low-loaded anodes based on intrinsically highly active but poorly conductive amorphous IrOx. In the presented study, a gas-diffusion electrode half-cell setup is used to promote an understanding of the underlying phenomena leading to this low performance. The influence of the PTL platinization on the performance of realistic porous transport electrodes (PTEs) for the oxygen evolution reaction (OER) is investigated by gradually increasing the platinum layer thickness for PTEs based on amorphous and rutile Ir-oxide. Electrochemical measurements show a beneficial influence of platinization on the activity for amorphous, but not for rutile Iroxide. Impedance analysis corroborates the formation of a Schottky-type interface between the PTL and the amorphous IrOx catalyst layers, depending on the PTL&apos;s platinum layer thickness. We presume that this heterogeneous Schottky-type interface induces an additional voltage drop and influences the utilization of the catalyst layer, leading to increased overpotentials. The measurements were complemented by inductively coupled plasma mass spectrometry showing constant integral amounts of Ir dissolving from the catalyst layers during the OER, independent of the platinization. Transferring the obtained knowledge to single cells, the whole composite anode, including e.g. the interplay between PTL and catalyst layer, must be optimized in conjunction to achieve optimum OER performance and long-term stability.

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

Chemical Engineering Journal

ISSN

1385-8947

e-ISSN

1873-3212

Svazek periodika

514

Číslo periodika v rámci svazku

Jun

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

15

Strana od-do

162887

Kód UT WoS článku

001494495400001

EID výsledku v databázi Scopus

2-s2.0-105003975203