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Dynamic in situ observation of rapid size and shape change of supported Pd nanoparticles during CO/NO cycling

Nature Materials volume 6, pages 528532 (2007) | Download Citation



Understanding and improving the behaviour of supported precious-metal catalysts for a vast array of environmentally and economically important processes is a central area of research in catalysis. The removal of toxic gases such as CO and NO, without forming others (such as N2O), is particularly important. By combining energy-dispersive extended X-ray absorption fine-structure spectroscopy with a vibrational spectroscopy (infrared) and mass spectrometry, at high time resolution, in a single in situ experiment, we dynamically observe and quantify CO-, and subsequent NO-, induced size and shape changes of Pd nanoparticles during CO/NO cycling. In doing so we demonstrate a novel, non-oxidative redispersion (for example, an increase in metal surface area) mechanism, and suggest a model to bridge the structural and reactive functions of supported Pd catalysts.

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The authors would like to thank the ESRF for access to facilities and for the funding that permitted the development of this experiment on ID24. T. Mairs, F. Perrin, G. Guilera and A. Kroner are thanked for the various contributions they have made to this work; S. Pascarelli and O. Mathon are thanked for their general support and stewardship of the beamline. Finally, we acknowledge the CYCIT (projects CTQ2004-03409/BQU and CTQ2006-15600/BQU) for financial support. C. Belver thanks the Spanish ‘Ministerio de Educación y Ciencia’ for a ‘Juan de la Cierva’ postdoctoral grant.

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  1. The European Synchrotron Radiation Facility, 6, Rue Jules Horowitz, BP-220, Grenoble, France

    • Mark A. Newton
  2. Instituto de Catalisis y Petroleoquímica, CSIC, C/Marie Curie 2, 28049 Madrid, Spain

    • Carolina Belver-Coldeira
    • , Arturo Martínez-Arias
    •  & Marcos Fernández-García


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Competing interests

The authors declare no competing financial interests.

Corresponding authors

Correspondence to Mark A. Newton or Marcos Fernández-García.

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