Support-free nanostructured Pt Cu electrocatalyst for the oxygen reduction reaction prepared by alternating magnetron sputtering

Gustav Wilhelm Sievers*, Jacob R. Bowen, Volker Brüser, Matthias Arenz

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Nanostructuring of electrocatalysts is an important aspect of catalyst design as catalytic performance depends not only on the specific activity (reaction rate per surface area), but also on the dispersion of the catalyst. We present an industrially compatible, but effective preparation method for support-free nanostructured catalyst layers. Alternating sputtering was used to prepare heterogeneous PtCu templates ranging from 95 up to 99.5 at. % Cu. These templates were then electrochemically leached to form a nanostructured PtCu network and benchmarked with respect to the oxygen reduction reaction. It is shown that the templates with lower Cu:Pt ratios exhibit the highest initial specific activity but have a relatively low electrochemically active surface area. Subjecting the samples to extended accelerated stress tests, it is found that the support-free nanostructured PtCu networks are relatively resistant to high potential cycling, which can be explained by the lack of carbon corrosion. The loss in electrochemical surface area thereby depends on the initial Pt content. The specific oxygen reduction activity, however, approaches the value of bulk Pt. Although this decrease is not desirable, still an (specific) activity improvement of two to four times as compared carbon supported nanoparticles can be preserved.
Original languageEnglish
JournalJournal of Power Sources
Volume413
Pages (from-to)432-440
Number of pages9
ISSN0378-7753
DOIs
Publication statusPublished - 2019

Keywords

  • Oxygen reduction reaction
  • Nanostructured catalysis
  • Fuel cells
  • Dealloying Platinum
  • Magnetron sputtering

Cite this

@article{00a95fb505b5443a80cc7c0637ebb35d,
title = "Support-free nanostructured Pt Cu electrocatalyst for the oxygen reduction reaction prepared by alternating magnetron sputtering",
abstract = "Nanostructuring of electrocatalysts is an important aspect of catalyst design as catalytic performance depends not only on the specific activity (reaction rate per surface area), but also on the dispersion of the catalyst. We present an industrially compatible, but effective preparation method for support-free nanostructured catalyst layers. Alternating sputtering was used to prepare heterogeneous PtCu templates ranging from 95 up to 99.5 at. {\%} Cu. These templates were then electrochemically leached to form a nanostructured PtCu network and benchmarked with respect to the oxygen reduction reaction. It is shown that the templates with lower Cu:Pt ratios exhibit the highest initial specific activity but have a relatively low electrochemically active surface area. Subjecting the samples to extended accelerated stress tests, it is found that the support-free nanostructured PtCu networks are relatively resistant to high potential cycling, which can be explained by the lack of carbon corrosion. The loss in electrochemical surface area thereby depends on the initial Pt content. The specific oxygen reduction activity, however, approaches the value of bulk Pt. Although this decrease is not desirable, still an (specific) activity improvement of two to four times as compared carbon supported nanoparticles can be preserved.",
keywords = "Oxygen reduction reaction, Nanostructured catalysis, Fuel cells, Dealloying Platinum, Magnetron sputtering",
author = "Sievers, {Gustav Wilhelm} and Bowen, {Jacob R.} and Volker Br{\"u}ser and Matthias Arenz",
year = "2019",
doi = "10.1016/j.jpowsour.2018.12.044",
language = "English",
volume = "413",
pages = "432--440",
journal = "Journal of Power Sources",
issn = "0378-7753",
publisher = "Elsevier",

}

Support-free nanostructured Pt Cu electrocatalyst for the oxygen reduction reaction prepared by alternating magnetron sputtering. / Sievers, Gustav Wilhelm; Bowen, Jacob R.; Brüser, Volker; Arenz, Matthias.

In: Journal of Power Sources, Vol. 413, 2019, p. 432-440.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Support-free nanostructured Pt Cu electrocatalyst for the oxygen reduction reaction prepared by alternating magnetron sputtering

AU - Sievers, Gustav Wilhelm

AU - Bowen, Jacob R.

AU - Brüser, Volker

AU - Arenz, Matthias

PY - 2019

Y1 - 2019

N2 - Nanostructuring of electrocatalysts is an important aspect of catalyst design as catalytic performance depends not only on the specific activity (reaction rate per surface area), but also on the dispersion of the catalyst. We present an industrially compatible, but effective preparation method for support-free nanostructured catalyst layers. Alternating sputtering was used to prepare heterogeneous PtCu templates ranging from 95 up to 99.5 at. % Cu. These templates were then electrochemically leached to form a nanostructured PtCu network and benchmarked with respect to the oxygen reduction reaction. It is shown that the templates with lower Cu:Pt ratios exhibit the highest initial specific activity but have a relatively low electrochemically active surface area. Subjecting the samples to extended accelerated stress tests, it is found that the support-free nanostructured PtCu networks are relatively resistant to high potential cycling, which can be explained by the lack of carbon corrosion. The loss in electrochemical surface area thereby depends on the initial Pt content. The specific oxygen reduction activity, however, approaches the value of bulk Pt. Although this decrease is not desirable, still an (specific) activity improvement of two to four times as compared carbon supported nanoparticles can be preserved.

AB - Nanostructuring of electrocatalysts is an important aspect of catalyst design as catalytic performance depends not only on the specific activity (reaction rate per surface area), but also on the dispersion of the catalyst. We present an industrially compatible, but effective preparation method for support-free nanostructured catalyst layers. Alternating sputtering was used to prepare heterogeneous PtCu templates ranging from 95 up to 99.5 at. % Cu. These templates were then electrochemically leached to form a nanostructured PtCu network and benchmarked with respect to the oxygen reduction reaction. It is shown that the templates with lower Cu:Pt ratios exhibit the highest initial specific activity but have a relatively low electrochemically active surface area. Subjecting the samples to extended accelerated stress tests, it is found that the support-free nanostructured PtCu networks are relatively resistant to high potential cycling, which can be explained by the lack of carbon corrosion. The loss in electrochemical surface area thereby depends on the initial Pt content. The specific oxygen reduction activity, however, approaches the value of bulk Pt. Although this decrease is not desirable, still an (specific) activity improvement of two to four times as compared carbon supported nanoparticles can be preserved.

KW - Oxygen reduction reaction

KW - Nanostructured catalysis

KW - Fuel cells

KW - Dealloying Platinum

KW - Magnetron sputtering

U2 - 10.1016/j.jpowsour.2018.12.044

DO - 10.1016/j.jpowsour.2018.12.044

M3 - Journal article

VL - 413

SP - 432

EP - 440

JO - Journal of Power Sources

JF - Journal of Power Sources

SN - 0378-7753

ER -