Solid solution alloy nanoparticles of immiscible Pd and Ru elements neighboring on Rh: changeover of the thermodynamic behavior for hydrogen storage and enhanced CO-oxidizing ability.
Pd(x)Ru(1-x) solid solution alloy nanoparticles were successfully synthesized over the whole composition range through a chemical reduction method, although Ru and Pd are immiscible at the atomic level in the bulk state. From the XRD measurement, it was found that the dominant structure of Pd(x)Ru(1-x) changes from fcc to hcp with increasing Ru content. The structures of Pd(x)Ru(1-x) nanoparticles in the Pd composition range of 30-70% consisted of both solid solution fcc and hcp structures, and both phases coexist in a single particle. In addition, the reaction of hydrogen with the Pd(x)Ru(1-x) nanoparticles changed from exothermic to endothermic as the Ru content increased. Furthermore, the prepared Pd(x)Ru(1-x) nanoparticles demonstrated enhanced CO-oxidizing catalytic activity; Pd0.5Ru0.5 nanoparticles exhibit the highest catalytic activity. This activity is much higher than that of the practically used CO-oxidizing catalyst Ru and that of the neighboring Rh, between Ru and Pd.
Division of Chemistry, Graduate School of Science, Kyoto University , Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan.
Kohei
K
Kusada
Hirokazu
H
Kobayashi
Ryuichi
R
Ikeda
Yoshiki
Y
Kubota
Masaki
M
Takata
Shoichi
S
Toh
Tomokazu
T
Yamamoto
Syo
S
Matsumura
Naoya
N
Sumi
Katsutoshi
K
Sato
Katsutoshi
K
Nagaoka
Hiroshi
H
Kitagawa
D000497:Alloys / Q000737:chemistry*; D002248:Carbon Monoxide / Q000737:chemistry*; D002384:Catalysis; D006859:Hydrogen / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry*; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*; D012238:Rhodium / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*; D013499:Surface Properties; D013816:Thermodynamics
D000497:Alloys; D010165:Palladium; D002248:Carbon Monoxide; D012428:Ruthenium; D006859:Hydrogen; D012238:Rhodium