Effect of Crystalline Phase and Composition on the Catalytic Properties of PdSn Bimetallic Nanoparticles in the PROX Reaction

• Published in: Journal of physical chemistry. C Vol. 118; no. 44; pp. 25392 - 25402
• Main Authors: Lanza, Roberto, Bersani, Marco, Conte, Luca, Martucci, Alessandro, Canu, Paolo, Guglielmi, Massimo, Mattei, Giovanni, Bello, Valentina, Centazzo, Massimo, Rosei, Renzo
• Format: Journal Article
• Language: English
• Published: American Chemical Society 06.11.2014
• Subjects: Bimetallic nanoparticles; Catalytic properties; Crystalline phase; PROX reaction
• ISSN: 1932-7447; 1932-7455; 1932-7455
• DOI: 10.1021/jp503531b

We present a synthetic strategy for the preparation of palladium–tin alloy and intermetallic nanoparticles. Complexes of palladium(II) and tin(IV) precursors in oleylamine were thermally decomposed in an organic solution in the presence of reducing moieties, leading to the formation of monodispersed nanoparticles with varying crystallographic structures. We found that the nanoparticles crystalline structure closely follows the bulk material phase diagram. The nanoparticles were supported on Al2O3 and their reactivity tested as catalysts for the preferential oxidation of CO in excess of hydrogen (PROX). Different Pd/Sn and O2/CO ratios have been investigated, and the structure–reactivity correlation highlighted. With increasing tin content, the CO ignition temperature remarkably lowers and the CO conversion rate increases, up to the formation of intermetallic phases that concurrently determine a reduction in the catalyst activity; the selectivity of the pure palladium references is preserved.