The Role of Tungsten Oxide in Enhancing the Carbon Monoxide Tolerance of Platinum-Based Hydrogen Oxidation Catalysts

Douglas W G Stewart; Keith Scott; Andrew J Wain; Timothy E Rosser; Edward Brightman; Donald Macphee; Mohamed Mamlouk

doi:10.1021/acsami.0c07804

The Role of Tungsten Oxide in Enhancing the Carbon Monoxide Tolerance of Platinum-Based Hydrogen Oxidation Catalysts

ACS Appl Mater Interfaces. 2020 Aug 19;12(33):37079-37091. doi: 10.1021/acsami.0c07804. Epub 2020 Aug 7.

Authors

Douglas W G Stewart^{1

2}, Keith Scott², Andrew J Wain³, Timothy E Rosser³, Edward Brightman^{1

4}, Donald Macphee^{1

5}, Mohamed Mamlouk²

Affiliations

¹ Enocell Ltd., BioCity Scotland, Motherwell ML1 5UH, U.K.
² Chemical Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, U.K.
³ National Physical Laboratory, Hampton Rd, Teddington TW11 0LW, U.K.
⁴ Department of Chemical and Process Engineering, University of Strathclyde, Glasgow G1 1XJ, U.K.
⁵ Department of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, U.K.

PMID: 32692534
DOI: 10.1021/acsami.0c07804

Abstract

Significant reductions in total cost of ownership can be realized by engineering PEM fuel cells to run on low-purity hydrogen. One of the main drawbacks of low-purity hydrogen fuels is the carbon monoxide fraction, which poisons platinum electrocatalysts and reduces the power output below useful levels. Platinum-tungsten oxide catalyst systems have previously shown high levels of CO tolerance during both ex situ and in situ investigations. In this work, we explore the mechanism of enhanced tolerance using in situ electrochemical attenuated total reflection-infrared (ATR-IR) and Raman spectroscopy methods and investigate, using a mixture of Pt/C and WO₃ powders, the role of the W^V/W^VI redox couple in the oxidation of adsorbed CO.

Keywords: ATR-IR; carbon monoxide oxidation; fuel cell; hydrogen; platinum; tungsten trioxide.