Controlling a spillover pathway with the molecular cork effect

Marcinkowski, Matthew D.; Jewell, April D.; Stamatakis, Michail; Boucher, Matthew B.; Lewis, Emily A.; Murphy, Colin J.; Kyriakou, Georgios; Sykes, E. Charles H.

Abstract

Spillover of reactants from one active site to another is important in heterogeneous catalysis and has recently been shown to enhance hydrogen storage in a variety of materials. The spillover of hydrogen is notoriously hard to detect or control. We report herein that the hydrogen spillover pathway on a Pd/Cu alloy can be controlled by reversible adsorption of a spectator molecule. Pd atoms in the Cu surface serve as hydrogen dissociation sites from which H atoms can spillover onto surrounding Cu regions. Selective adsorption of CO at these atomic Pd sites is shown to either prevent the uptake of hydrogen on, or inhibit its desorption from, the surface. In this way, the hydrogen coverage on the whole surface can be controlled by molecular adsorption at a minority site, which we term a ‘molecular cork’ effect. We show that the molecular cork effect is present during a surface catalysed hydrogenation reaction and illustrate how it can be used as a method for controlling uptake and release of hydrogen in a model storage system

Citation

Marcinkowski, M. D., Jewell, A. D., Stamatakis, M., Boucher, M. B., Lewis, E. A., Murphy, C. J., Kyriakou, G., & Sykes, E. C. H. (2013). Controlling a spillover pathway with the molecular cork effect. Nature Materials, 12(6), 523-528. https://doi.org/10.1038/nmat3620

• Journal Article Type: Article
• Acceptance Date: Mar 5, 2013
• Online Publication Date: Apr 21, 2013
• Publication Date: Jun 1, 2013
• Deposit Date: Nov 13, 2014
• Publicly Available Date: Nov 23, 2017
• Journal: Nature materials
• Print ISSN: 1476-1122
• Publisher: Nature Publishing Group
• Peer Reviewed: Peer Reviewed
• Volume: 12
• Issue: 6
• Pages: 523-528
• DOI: https://doi.org/10.1038/nmat3620
• Keywords: Heterogeneous catalysis; Surfaces, interfaces and thin films
• Public URL: https://hull-repository.worktribe.com/output/470479
• Publisher URL: http://www.nature.com/nmat/journal/v12/n6/full/nmat3620.html#affil-auth
• Additional Information: Author's accepted manuscript of article published in: Nature materials, 2013, v.12, issue 6
• Contract Date: Nov 23, 2017