CO Oxidation and Site Speciation for Alloyed Pd-Pt Model Catalysts Studied by In Situ FTIR Spectroscopy
Journal article, 2017

In situ Fourier transform infrared spectroscopy was used to study transient CO oxidation over a series of bimetallic Pd-Pt catalysts with different Pd:Pt molar ratios. The catalysts were found to contain both alloyed PdPt nanoparticles (particle sizes 25-35 nm) and monometallic Pd nanoparticles (sizes below 10 nm). For oxygen-free conditions, CO reduces the surface while simultaneously function as a chemical probe molecule whereby the CO adsorption sites can be characterised. Under these conditions it is shown that adsorbed carbonyl species form both on the Pd and Pt. On platinum, CO adsorbs predominantly linearly on top, whereas on palladium it adsorbes in bridged configurations. This behaviour is used for site speciation of the catalysts. The spectra from the bimetallic Pd-Pt catalysts are more complicated than a direct superposition of the spectra for the monometallic catalysts as a consequence of alloy formation and enrichment of Pd at the surface of the reduced catalysts. The temperature programmed CO oxidation results show that the addition of Pd to the Pt catalyst supported on alumina shifts the CO-poisoned state to lower temperatures therefore increasing the temperature range for the CO oxidation at low temperatures.

Author

Natalia Mihaela Martin

Competence Centre for Catalysis (KCK)

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Magnus Skoglundh

Competence Centre for Catalysis (KCK)

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Gudmund Smedler

Johnson Matthey AB

Agnes Raj

Johnson Matthey

David Thompsett

Johnson Matthey

Francisco Javier Martinez-Casado

MAX IV Laboratory

Zdenek Matej

MAX IV Laboratory

Olivier Balmes

MAX IV Laboratory

Per-Anders Carlsson

Competence Centre for Catalysis (KCK)

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Journal of Physical Chemistry C

1932-7447 (ISSN) 1932-7455 (eISSN)

Vol. 121 47 26321-26329

Fundamental studies on the influence of water on oxidation catalysts for biogas applications

Swedish Energy Agency, 2015-04-01 -- 2019-03-31.

Driving Forces

Sustainable development

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Transport

Energy

Materials Science

Subject Categories

Physical Chemistry

Chemical Process Engineering

DOI

10.1021/acs.jpcc.7b07611

More information

Latest update

7/2/2019 3