Au–Rh and Au–Pd nanocatalysts supported on rutile titania nanorods: structure and chemical stability

Research output: Contribution to journalArticle

Authors

  • Zere Konuspayeva
  • Pavel Afanasiev
  • Thanh-son Nguyen
  • Luca Di Felice
  • Franck Morfin
  • Nhat-tai Nguyen
  • Jaysen Nelayah
  • Christian Ricolleau
  • Jun Yuan
  • Gilles Berhault
  • Laurent Piccolo

Colleges, School and Institutes

External organisations

  • Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), UMR 5256 CNRS & Université Claude Bernard – Lyon 1, 2 avenue Albert Einstein, 69626 Villeurbanne
  • Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), UMR 5256 CNRS & Université Claude Bernard – Lyon 1, 2 avenue Albert Einstein, 69626 Villeurbanne
  • Laboratoire Matériaux et Phénomènes Quantiques (MPQ), UMR 7162 CNRS & Université Paris-Diderot, Bâtiment Condorcet, 4 rue Elsa Morante, 75205 Paris Cedex 13
  • Department of Physics, University of York, Heslington, York YO10 5DD, UK

Abstract

Au, Rh, Pd, Au–Rh and Au–Pd nanoparticles (NPs) were synthesized by colloidal chemical reduction and immobilized on hydrothermally-prepared rutile titania nanorods. The catalysts were characterized by aberration-corrected TEM/STEM, XPS, and FTIR, and were evaluated in the hydrogenation of tetralin in the presence of H2S. Oxidizing and reducing thermal treatments were employed to remove the polyvinyl alcohol (PVA) surfactant. Reduction in H2 at 350 °C was found efficient for removing the PVA while preserving the size (ca. 3 nm), shape and bimetallic nature of the NPs. While Au–Pd NPs are alloyed at the atomic scale, Au–Rh NPs contain randomly distributed single-phase domains. Calcination–reduction of Au–Rh NPs mostly leads to separated Au and Rh NPs, while pre-reduction generates a well-defined segregated structure with Rh located at the interface between Au and TiO2 and possibly present around the NPs as a thin overlayer. Both the titania support and gold increase the resistance of Rh and Pd to oxidation. Furthermore, although detrimental to tetralin hydrogenation initial activity, gold stabilizes the NPs against surface sulfidation in the presence of 50 ppm H2S, leading to increased catalytic performances of the Au–Rh and Au–Pd systems as compared to their Rh and Pd counterparts.

Details

Original languageEnglish
Pages (from-to)28112-28120
Number of pages9
JournalPhysical Chemistry Chemical Physics
Volume17
Issue number42
Early online date6 Mar 2015
Publication statusPublished - 14 Nov 2015