Science1 publisher2 min readPublished
Platinum-copper and platinum-iron on MXene divide fuel-cell activity and durability between them
Sharon Benny Alex and colleagues found platinum-copper on MXene the more active of two fuel-cell catalysts and platinum-iron the more durable. In-situ X-ray data tie iron's longer life to a bond with the support. The study does not quantify how much platinum that saves.
The Scientist · Science desk
What happened
- Cheaper metals alloyed into platinum raise efficiency but can leach out during operation, so the catalyst loses activity over time.
- The team credits strong iron-oxygen-MXene interactions with stabilising the platinum-iron catalyst during long-term operation.
- In-situ X-ray spectroscopy let the researchers watch the structural and electronic changes in the catalysts while they were operating.
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Why it matters
- decision A designer working from these results still has to choose between copper's faster oxygen reduction and iron's longer life, since neither MXene catalyst delivered both.
- capability Observing catalysts in operation links stability to a specific iron-oxygen bond with the support, giving later alloy designs a concrete feature to look for.
- cost Any saving on expensive platinum stays unquantified until loadings and lifetimes are published against a conventional platinum catalyst.
For an MXene support to ease the old compromise, one catalyst on it would have to be both the fastest and the longest-lived. In this study the two properties ended up in different alloys [7][8].
The compromise comes from one slow step. At the cathode, oxygen from the air is reduced, and that reaction is one of the main limits on fuel-cell performance [2]. Platinum speeds it up. But platinum is expensive and degrades during operation [3]. Mixing in a cheaper metal improves efficiency until that metal leaches out and activity falls [4]. The researchers set out to address this trade-off directly by comparing copper and iron as the alloying partner [5].
The durability result traces back to the support, according to the Physics World summary. MXene is a two-dimensional material similar to graphene, and it helps hold the metal nanoparticles in place [6]. For the iron alloy, the team credits strong Fe-O-MXene interactions with stabilising the catalyst over long-term operation [8]. Put plainly, the iron is linked through oxygen to the support. Copper does something different: it modifies the platinum surface so oxygen reduction runs faster [7].
The design choice I like is the in-situ X-ray spectroscopy. The team watched the catalysts while they were working [9]. A catalyst examined only before and after a durability test shows the damage but not the order in which it happened. Observing during operation let the researchers identify the structural and electronic changes behind each alloy's performance [9].
The chemistry described fits the idea that less platinum could be used without losing lifetime. The summary does not report activity values, platinum loadings, durability cycle counts or the test setup. Without those numbers, neither catalyst can be judged against a conventional platinum baseline, in a lab cell or in a working stack.
I think the result worth keeping is the iron-oxygen-support bond. It is a specific chemical feature, linked to stability, that can be looked for in other alloys. The summary calls the study a roadmap for developing improved catalysts for future fuel cells [10]. The paper is Sharon Benny Alex et al, Progress in Energy, volume 8, article 035003, published in 2026 [11].
What to watch
- Whether the full Progress in Energy paper reports platinum mass activity and cycle-count durability against a standard platinum catalyst.
- Whether a copper-containing alloy can be anchored to MXene as strongly as iron, combining the higher activity with the longer life.
- Tests of either catalyst in a full fuel-cell stack under operating conditions.