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Đukić T, Moriau L, Klofutar I, Šala M, Pavko L, González López FJ, Ruiz-Zepeda F, Pavlišič A, Hotko M, Gatalo M, Hodnik N. Adjusting the Operational Potential Window as a Tool for Prolonging the Durability of Carbon-Supported Pt-Alloy Nanoparticles as Oxygen Reduction Reaction Electrocatalysts. ACS Catal 2024; 14:4303-4317. [PMID: 38510667 PMCID: PMC10949198 DOI: 10.1021/acscatal.3c06251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 02/13/2024] [Accepted: 02/22/2024] [Indexed: 03/22/2024]
Abstract
A current trend in the investigation of state-of-the-art Pt-alloys as proton exchange membrane fuel cell (PEMFC) electrocatalysts is to study their long-term stability as a bottleneck for their full commercialization. Although many parameters have been appropriately addressed, there are still certain issues that must be considered. Here, the stability of an experimental Pt-Co/C electrocatalyst is investigated by high-temperature accelerated degradation tests (HT-ADTs) in a high-temperature disk electrode (HT-DE) setup, allowing the imitation of close-to-real operational conditions in terms of temperature (60 °C). Although the US Department of Energy (DoE) protocol has been chosen as the basis of the study (30,000 trapezoidal wave cycling steps between 0.6 and 0.95 VRHE with a 3 s hold time at both the lower potential limit (LPL) and the upper potential limit (UPL)), this works demonstrates that limiting both the LPL and UPL (from 0.6-0.95 to 0.7-0.85 VRHE) can dramatically reduce the degradation rate of state-of-the-art Pt-alloy electrocatalysts. This has been additionally confirmed with the use of an electrochemical flow cell coupled to inductively coupled plasma mass spectrometry (EFC-ICP-MS), which enables real-time monitoring of the dissolution mechanisms of Pt and Co. In line with the HT-DE methodology observations, a dramatic decrease in the total dissolution of Pt and Co has once again been observed upon narrowing the potential window to 0.7-0.85 VRHE rather than 0.6-0.95 VRHE. Additionally, the effect of the potential hold time at both LPL and UPL on metal dissolution has also been investigated. The findings demonstrate that the dissolution rate of both metals is proportional to the hold time at UPL regardless of the applied potential window, whereas the hold time at the LPL does not appear to be as detrimental to the stability of metals.
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Affiliation(s)
- Tina Đukić
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, Ljubljana 1001, Slovenia
- Faculty
of Chemistry and Chemical Technology, University
of Ljubljana, Večna
pot 113, Ljubljana 1000, Slovenia
| | - Léonard
Jean Moriau
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, Ljubljana 1001, Slovenia
| | - Iva Klofutar
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, Ljubljana 1001, Slovenia
| | - Martin Šala
- Department
of Analytical Chemistry, National Institute
of Chemistry, Hajdrihova
19, Ljubljana 1001, Slovenia
| | - Luka Pavko
- ReCatalyst
d.o.o., Hajdrihova Ulica
19, Ljubljana 1001, Slovenia
| | | | - Francisco Ruiz-Zepeda
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, Ljubljana 1001, Slovenia
| | - Andraž Pavlišič
- Department
of Catalysis and Chemical Reaction Engineering, National Institute of Chemistry, Hajdrihova 19, Ljubljana 1001, Slovenia
| | - Miha Hotko
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, Ljubljana 1001, Slovenia
- University
of Nova Gorica, Vipavska
13, Nova Gorica 5000, Slovenia
| | - Matija Gatalo
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, Ljubljana 1001, Slovenia
- ReCatalyst
d.o.o., Hajdrihova Ulica
19, Ljubljana 1001, Slovenia
| | - Nejc Hodnik
- Department
of Materials Chemistry, National Institute
of Chemistry, Hajdrihova
19, Ljubljana 1001, Slovenia
- University
of Nova Gorica, Vipavska
13, Nova Gorica 5000, Slovenia
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