Boosting Oxygen Reduction at Pt(111)|Proton Exchange Ionomer Interfaces through Tuning the Microenvironment Water Activity
A proton exchange ionomer is one of the most important components in membrane electrode assemblies (MEAs) of polymer electrolyte membrane fuel cells (PEMFCs). It acts as both a proton conductor and a binder for nanocatalysts and carbon supports. The structure and the wetting conditions of the MEAs have a great impact on the microenvironment at the three-phase interphases in the MEAs, which can significantly influence the electrode kinetics such as the oxygen reduction reaction (ORR) at the cathode. Herein, by using the Pt(111)|X ionomer interface as a model system (X = Nafion, Aciplex, D72), we find that higher drying temperature lowers the onset potential for sulfonate adsorption and reduces apparent ORR current, while the current wave for OHad formation drops and shifts positively. Surprisingly, the intrinsic ORR activity is higher after properly correcting the blocking effect of Pt active sites by sulfonate adsorption and the poly(tetrafluoroethylene) (PTFE) skeleton. These results are well explained by the reduced water activity at the interfaces induced by the ionomer/PTFE, according to the mixed potential effect. Implications for how to prepare MEAs with improved ORR activity are provided.
| Medienart: |
E-Artikel |
|---|
| Erscheinungsjahr: |
2024 |
|---|---|
| Erschienen: |
2024 |
| Enthalten in: |
Zur Gesamtaufnahme - volume:16 |
|---|---|
| Enthalten in: |
ACS applied materials & interfaces - 16(2024), 4 vom: 31. Jan., Seite 4540-4549 |
| Sprache: |
Englisch |
|---|
| Beteiligte Personen: |
Xu, Yujun [VerfasserIn] |
|---|
| Links: |
|---|
| Themen: |
Adsorption |
|---|
| Anmerkungen: |
Date Revised 31.01.2024 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
|---|
| doi: |
10.1021/acsami.3c14208 |
|---|
| funding: |
|
|---|---|
| Förderinstitution / Projekttitel: |
|
| PPN (Katalog-ID): |
NLM36718480X |
|---|
| LEADER | 01000caa a22002652 4500 | ||
|---|---|---|---|
| 001 | NLM36718480X | ||
| 003 | DE-627 | ||
| 005 | 20240131232044.0 | ||
| 007 | cr uuu---uuuuu | ||
| 008 | 240117s2024 xx |||||o 00| ||eng c | ||
| 024 | 7 | |a 10.1021/acsami.3c14208 |2 doi | |
| 028 | 5 | 2 | |a pubmed24n1276.xml |
| 035 | |a (DE-627)NLM36718480X | ||
| 035 | |a (NLM)38227931 | ||
| 040 | |a DE-627 |b ger |c DE-627 |e rakwb | ||
| 041 | |a eng | ||
| 100 | 1 | |a Xu, Yujun |e verfasserin |4 aut | |
| 245 | 1 | 0 | |a Boosting Oxygen Reduction at Pt(111)|Proton Exchange Ionomer Interfaces through Tuning the Microenvironment Water Activity |
| 264 | 1 | |c 2024 | |
| 336 | |a Text |b txt |2 rdacontent | ||
| 337 | |a ƒaComputermedien |b c |2 rdamedia | ||
| 338 | |a ƒa Online-Ressource |b cr |2 rdacarrier | ||
| 500 | |a Date Revised 31.01.2024 | ||
| 500 | |a published: Print-Electronic | ||
| 500 | |a Citation Status PubMed-not-MEDLINE | ||
| 520 | |a A proton exchange ionomer is one of the most important components in membrane electrode assemblies (MEAs) of polymer electrolyte membrane fuel cells (PEMFCs). It acts as both a proton conductor and a binder for nanocatalysts and carbon supports. The structure and the wetting conditions of the MEAs have a great impact on the microenvironment at the three-phase interphases in the MEAs, which can significantly influence the electrode kinetics such as the oxygen reduction reaction (ORR) at the cathode. Herein, by using the Pt(111)|X ionomer interface as a model system (X = Nafion, Aciplex, D72), we find that higher drying temperature lowers the onset potential for sulfonate adsorption and reduces apparent ORR current, while the current wave for OHad formation drops and shifts positively. Surprisingly, the intrinsic ORR activity is higher after properly correcting the blocking effect of Pt active sites by sulfonate adsorption and the poly(tetrafluoroethylene) (PTFE) skeleton. These results are well explained by the reduced water activity at the interfaces induced by the ionomer/PTFE, according to the mixed potential effect. Implications for how to prepare MEAs with improved ORR activity are provided | ||
| 650 | 4 | |a Journal Article | |
| 650 | 4 | |a Pt(111) | |
| 650 | 4 | |a adsorption | |
| 650 | 4 | |a ionomer | |
| 650 | 4 | |a oxygen reduction reaction | |
| 650 | 4 | |a water activity | |
| 700 | 1 | |a Zhang, Lulu |e verfasserin |4 aut | |
| 700 | 1 | |a Chen, Wei |e verfasserin |4 aut | |
| 700 | 1 | |a Cui, Haowen |e verfasserin |4 aut | |
| 700 | 1 | |a Cai, Jun |e verfasserin |4 aut | |
| 700 | 1 | |a Chen, Yanxia |e verfasserin |4 aut | |
| 700 | 1 | |a Feliu, Juan M |e verfasserin |4 aut | |
| 700 | 1 | |a Herrero, Enrique |e verfasserin |4 aut | |
| 773 | 0 | 8 | |i Enthalten in |t ACS applied materials & interfaces |d 2009 |g 16(2024), 4 vom: 31. Jan., Seite 4540-4549 |w (DE-627)NLM194100049 |x 1944-8252 |7 nnns |
| 773 | 1 | 8 | |g volume:16 |g year:2024 |g number:4 |g day:31 |g month:01 |g pages:4540-4549 |
| 856 | 4 | 0 | |u http://dx.doi.org/10.1021/acsami.3c14208 |3 Volltext |
| 912 | |a GBV_USEFLAG_A | ||
| 912 | |a GBV_NLM | ||
| 951 | |a AR | ||
| 952 | |d 16 |j 2024 |e 4 |b 31 |c 01 |h 4540-4549 | ||