Self-supported Pt–CoO networks combining high specific activity with high surface area for oxygen reduction

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningfagfællebedømt

  • Gustav W. Sievers
  • Anders W. Jensen
  • Alessandro Zana
  • Francesco Bizzotto
  • Mehtap Oezaslan
  • Alexandra Dworzak
  • Thomas E. L. Smitshuysen
  • Shima Kadkhodazadeh
  • Mikkel Juelsholt
  • Kirsten Anklam
  • Hao Wan
  • Jan Schäfer
  • Klára Čépe
  • Antje Quade
  • Volker Brüser

Several concepts for platinum-based catalysts for the oxygen reduction reaction (ORR) are presented that exceed the US Department of Energy targets for Pt-related ORR mass activity. Most concepts achieve their high ORR activity by increasing the Pt specific activity at the expense of a lower electrochemically active surface area (ECSA). In the potential region controlled by kinetics, such a lower ECSA is counterbalanced by the high specific activity. At higher overpotentials, however, which are often applied in real systems, a low ECSA leads to limitations in the reaction rate not by kinetics, but by mass transport. Here we report on self-supported platinum–cobalt oxide networks that combine a high specific activity with a high ECSA. The high ECSA is achieved by a platinum–cobalt oxide bone nanostructure that exhibits unprecedentedly high mass activity for self-supported ORR catalysts. This concept promises a stable fuel-cell operation at high temperature, high current density and low humidification.

OriginalsprogEngelsk
TidsskriftNature Materials
Vol/bind20
Sider (fra-til)208–213
Antal sider8
ISSN1476-1122
DOI
StatusUdgivet - 2021

ID: 248030240