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Transition metal/polymer catalysts for O2 reduction

Advances in Electrocatalysis, Materials, Diagnostics and Durability

Electrocatalyst materials for low temperature fuel cells

Novel catalysts

  1. C. M. Johnston1,
  2. P. Piela2,
  3. P. Zelenay1

Published Online: 15 DEC 2010

DOI: 10.1002/9780470974001.f500004

Handbook of Fuel Cells

Handbook of Fuel Cells

How to Cite

Johnston, C. M., Piela, P. and Zelenay, P. 2010. Transition metal/polymer catalysts for O2 reduction. Handbook of Fuel Cells. .

Author Information

  1. 1

    Los Alamos National Laboratory, NM, USA

  2. 2

    Industrial Chemistry Research Institute, Warsaw, Poland

Publication History

  1. Published Online: 15 DEC 2010

Abstract

Transition metal/polymer catalysts for O2 reduction have been investigated extensively as a less expensive, more abundant alternative to platinum catalysts for polymer electrolyte fuel cell (PEFC) cathodes. Embedding metals into polymers offers many potential advantages analogous to the function of metal-containing enzymes, which include bringing the metal centers into proximity for cooperative action and moderating the local pH near the metal to improve catalyst stability. In this article, we critically summarize the developments in this category of catalysts. While many of the anticipated benefits of the transition metal/polymer catalysts are still to be demonstrated, the most successful aspect of using polymer matrices thus far has been the improved durability. Some newer systems have shown stability for hundreds of hours in the real (acidic) PEFC environment, which was not previously observed for nonprecious catalysts of any type. Although the activity must be increased before any nonprecious metal catalysts are commercially viable, the rich chemistry of polymers allows for many pathways of improvement. We discuss current efforts to understand the structure and action of the active sites and, based on that discussion and research reported to date, suggest future work in the field of oxygen reduction electrocatalysis using transition metal/polymer catalysts.

Keywords:

  • polymer electrolyte fuel cell;
  • PEFC;
  • PEMFC;
  • oxygen reduction;
  • ORR;
  • catalysis;
  • electrocatalysis;
  • metal/polymer composite;
  • transition metals;
  • conducting polymers