An Investigation into the Bulk and Surface Phase Transformations of Bimetallic Pd-In/Al₂O₃ Catalyst during Reductive and Oxidative Treatments In Situ

• Main Authors: Nadezhda S. Smirnova, Evgeny V. Khramov, Galina N. Baeva, Pavel V. Markov, Andrey V. Bukhtiyarov, Yan V. Zubavichus, Aleksander Y. Stakheev
• Format: Article
• Language: English
• Published: MDPI AG 2021-07-01
• Series: Catalysts
• Subjects: intermetallic compounds; PdIn catalysts; in situ XAFS spectroscopy; DRIFTS of adsorbed CO
• Online Access: https://www.mdpi.com/2073-4344/11/7/859
• ISSN: 2073-4344

A series of oxidative treatments of PdIn-supported intermetallic nanoparticles at different temperatures were performed. The bulk and surface structure of catalyst during phase transformation was investigated by bulk- and surface-sensitive techniques (in situ XAFS, DRIFTS of adsorbed CO). It was found that comparison of palladium and indium fractions in bulk and on the surface suggests the formation of a «core-shell» structure. According to obtained results, the core consists of In-depleted intermetallic compound or inhomogeneous bimetallic phase with the inner core of metallic Pd, when a mixture of indium oxide, metallic palladium and small part of PdIn is present on the surface.