Niobia-Supported Palladium–Manganese Materials: Synthesis and Structural Investigation

✍ Scribed by Roberta Brayner; Françoise Villain; Leon Gengembre; Souad Ammar; François Bozon-Verduraz

• Book ID: 102164769
• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 372 KB
• Volume: 2008
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/ejic.200701018

✦ Synopsis

Abstract

Pd/niobia, Mn/niobia, and bimetallic Pd–Mn/niobia materials, which are catalysts for the total oxidation of ethanal,were prepared by anchoring molecular precursors, Pd(acac)~2~and/or Mn(acac)~2~, on niobia before calcination at 400 °C and reduction by either soft chemical routes in liquid medium (Pd‐based samples) or at 600 °C in H~2~ (Mn/niobia sample). The structure of the obtained materials was investigated by FTIR spectroscopy of adsorbed CO, transmission electron microscopy, X‐ray photoelectron spectroscopy, and extended X‐ray absorption fine structure–X‐ray absorption near edge spectroscopy. On Mn/niobia, Mn^2+^ is largely predominant, in spite of the high reduction temperature used for this sample, and it is mainly engaged in manganese niobate MnNb~2~O~6~. On Pd/niobia, nanoparticles of palladium metal (mean particle size 2.7 nm) are predominant, with a contribution of Pd^2+^. The surface structure of Pd–Mn/niobia is rather complex. Palladium is distributed between Pd~3~Mn nanoparticles and palladium clusters, and both are partially covered by oxygen atoms, whereas Mn^2+^ ions are engaged in MnO clusters linked to niobia. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)