Reversible Transformations of Palladium–Indium Intermetallic Nanoparticles upon Repetitive Redox Treatments in H[sub.2]/O[sub.2]

• Published in: Crystals (Basel) Vol. 13; no. 9
• Main Authors: Bukhtiyarov, Andrey V, Panafidin, Maxim A, Prosvirin, Igor P, Smirnova, Nadezhda S, Markov, Pavel V, Baeva, Galina N, Mashkovsky, Igor S, Bragina, Galina O, Vinokurov, Zakhar S, Zubavichus, Yan V, Bukhtiyarov, Valerii I, Stakheev, Alexander Yu
• Format: Journal Article
• Language: English
• Published: MDPI AG 01-09-2023
• Subjects: Indium; Palladium; Russia
• ISSN: 2073-4352; 2073-4352
• DOI: 10.3390/cryst13091356

The transformations of chemical states and structures occurring in the PdIn/Al[sub.2]O[sub.3] catalyst upon redox treatments in different gaseous atmospheres at different temperatures are addressed by an assortment of in situ bulk- (XRD) and surface-sensitive (XPS and DRIFTS CO) techniques. Any desired state of the catalyst between two opposite extremes of highly dispersed oxide species and regularly ordered PdIn intermetallic compound could be set in fully controlled and reversible ways by selecting appropriate conditions for the reductive treatment starting from the fully oxidized state. Since mutual conversions of multi-atomic Pd[sub.n] centers into single-site Pd[sub.1] centers are involved in these transformations, the methodology could be used to find an optimum balance between the activity and selectivity of the catalytic system.