Standard Article

Dealloyed Pt bimetallic electrocatalysts for oxygen reduction

Advances in Electrocatalysis, Materials, Diagnostics and Durability

Electrocatalyst materials for low temperature fuel cells

Novel catalysts

  1. P. Strasser

Published Online: 15 DEC 2010

DOI: 10.1002/9780470974001.f500003

Handbook of Fuel Cells

Handbook of Fuel Cells

How to Cite

Strasser, P. 2010. Dealloyed Pt bimetallic electrocatalysts for oxygen reduction. Handbook of Fuel Cells. .

Author Information

  1. University of Houston, Houston, TX, USA

Publication History

  1. Published Online: 15 DEC 2010

Abstract

In this article we report on the concept, synthesis, structural characterization, and surface catalytic performance of a new class of multimetallic Pt alloy nanoparticle electrocatalysts for the electroreduction of molecular oxygen in polymer electrolyte membrane (PEM) fuel cell–relevant acidic environments. Rotating disk electrode measurements as well as single fuel cell tests have shown that this class of cathode catalysts yield Pt mass-based and Pt surface-area-based oxygen reduction reaction (ORR) activities, which are a factor of 4–6 times higher than those of pure Pt. Hence, at present, this catalyst system constitutes one of the most active ORR catalyst systems ever reported.

We also present and discuss a novel method to deploy carbon-supported dealloyed Pt bi- and multimetallic nanoparticles as cathode electrocatalysts in electrode layers of single fuel cell membrane electrode assemblies (MEAs). We demonstrate the voltammetric insitu preparation of dealloyed bimetallic Pt–Cu, and report preliminary results on dealloyed Pt–Co–Cu ternary cathode electrode catalysts. We conclude with a discussion of our current hypothesis as to the mechanistic origin of the catalytic activity enhancement as well as with preliminary results as to the stability of this class of catalysts.

Keywords:

  • fuel cells;
  • alloy electrocatalysts;
  • Pt;
  • Cu;
  • dealloying;
  • dissolution;
  • oxygen reduction reaction;
  • lattice strain;
  • geometric effects;
  • small angle X-ray scattering;
  • core–shell catalysts