Gamma-Alumina-Supported Pt-17 Cluster: Controlled Loading, Geometrical Structure, And Size-Specific Catalytic Activity For Carbon Monoxide And Propylene Oxidation

Although Pt is extensively used as a catalyst to purify automotive exhaust gas, it is desirable to reduce Pt consumption through size reduction because Pt is a rare element and an expensive noble metal. In this study, we successfully loaded a Pt-17 cluster on gamma-alumina (gamma-Al2O3) (Pt-17/gamma-Al2O3) using [Pt-17(CO)(12)(PPh3)(8)]Cl-n (n = 1, 2) as a precursor. In addition, we demonstrated that Pt is not present in the form of an oxide in Pt-17/gamma-Al2O3 but instead has a framework structure as a metal cluster. Moreover, we revealed that Pt-17/gamma-Al2O3 exhibits higher catalytic activity for carbon monoxide and propylene oxidation than gamma-Al2O3-supported larger Pt nanoparticles (Pt-NP/gamma-Al2O3) prepared using the conventional impregnation method. Recently, our group discovered a simple method for synthesizing the precursor [Pt-17(CO)(12)(PPh3)(8)]Cl-n. Furthermore, Pt-17 is a Pt cluster within the size range associated with high catalytic activity. By combining our established synthesis and loading methods, other groups can conduct further research on Pt-17/gamma-Al2O3 to explore its catalytic activities in greater depth.