Controlling the charge state of supported nanoparticles in catalysis: lessons from model systems
Open Access
- 26 April 2018
- journal article
- review article
- Published by Royal Society of Chemistry (RSC) in Chemical Society Reviews
- Vol. 47 (22), 8474-8502
- https://doi.org/10.1039/c8cs00152a
Abstract
Model systems are very important to identify the working principles of real catalysts, and to develop concepts that can be used in the design of new catalytic materials. In this review we report examples of the use of model systems to better understand and control the occurrence of charge transfer at the interface between supported metal nanoparticles and oxide surfaces. In the first part of this article we concentrate on the nature of the support, and on the basic difference in metal/oxide bonding going from a wide-gap non-reducible oxide material to reducible oxide semiconductors. The roles of oxide nanostructuring, bulk and surface defectiveness, and doping with hetero-atoms are also addressed, as they are all aspects that severely affect the metal/oxide interaction. Particular attention is given to the experimental measures of the occurrence of charge transfer at the metal/oxide interface. In this respect, systems based on oxide ultrathin films are particularly important as they allow the use of scanning probe spectroscopies which, often in combination with other measurements and with first principles theoretical simulations, allow full characterization of small supported nanoparticles and their charge state. In a few selected cases, a precise count of the electrons transferred between the oxide and the supported nanoparticle has been possible. Charge transfer can occur through thin, two-dimensional oxide layers also thanks to their structural flexibility. The flow of charge through the oxide film and the formation of charged adsorbates are accompanied in fact by a substantial polaronic relaxation of the film surface which can be rationalized based on electrostatic arguments. In the final part of this review the relationships between model systems and real catalysts are addressed by discussing some examples of how lessons learned from model systems have helped in rationalizing the behavior of real catalysts under working conditions.Funding Information
- Ministero dell'Istruzione, dell'Università e della Ricerca (2015K7FZLH SMARTNESS)
- Deutsche Forschungsgemeinschaft (FR554718-1)
This publication has 266 references indexed in Scilit:
- Li/Mo Codoping of CaO Films: A Means to Tailor the Equilibrium Shape of Au DepositsJournal of the American Chemical Society, 2012
- Tailoring the Shape of Metal Ad‐Particles by Doping the Oxide SupportAngewandte Chemie-International Edition, 2011
- Oxide Films at the Nanoscale: New Structures, New Functions, and New MaterialsAccounts of Chemical Research, 2011
- Promotional effect of metal encapsulation on reactivity of iron oxide supported Pt catalystsApplied Catalysis A: General, 2011
- Oxygen-Induced Transformations of an FeO(111) Film on Pt(111): A Combined DFT and STM StudyThe Journal of Physical Chemistry C, 2010
- Structure and vibrational spectra of crystalline SiO2 ultra-thin films on Mo(112)Surface Science, 2005
- Influence of a HeterogeneousSurface on the Electronic Properties of Single Pd AtomsPhysical Review Letters, 2003
- Catalysis and corrosion: the theoretical surface-science contextSurface Science, 2002
- First-principles study of thesurface reduction upon Na adsorptionPhysical Review B, 2001
- Metal deposits on well-ordered oxide filmsProgress in Surface Science, 1999