We demonstrate that Pd nanospheres exhibit much higher susceptibility of the localized surface plasmon resonance (LSPR) peak to medium refractive index changes than commonly used plasmonic sensing materials such as Au and Ag. The susceptibility of spherical Au nanoparticle-core/Pd-shell nanospheres (Au/PdNSs, ca. 73 nm in diameter) was found to be 4.9 and 2.5 times higher, respectively, than those of Au (AuNSs) and Ag nanospheres (AgNSs) having similar diameters. The experimental finding was theoretically substantiated using the Mie exact solution. We also showed from a quasi-static (QS) approximation framework that the high susceptibility of Pd LSPR originates from the smaller dispersion of the real part of its dielectric function than those of Au and Ag LSPR around the resonant wavelength. We conclude that the Pd nanoparticle is a promising candidate of "the third plasmonic sensing material" following Au and Ag to be used in ultrahigh-sensitive LSPR sensors.

Nanoporous CeO2 samples as supports were prepared by chemical dealloying Ce-Al amorphous alloy, followed by synthesis of Au-Pd/CeO2 catalysts. The synthesized Au-Pd/CeO2 catalysts showed higher catalytic activity for hydrogen generation from formic acid than catalysts using supports prepared from a crystalline alloy precursor.

CeO 2 supports were prepared via a dealloying method from amorphous alloy. The activities of Ru/CeO 2 catalysts were examined in the hydrogen generation reaction from ammonia borane. To investigate the effects of atomic arrangement of CeO 2 precursor on the activities of Ru/ CeO 2 catalysts, CeO 2 supports were prepared from amorphous alloys and crystalline alloys. The use of amorphous alloys as the precursor of CeO 2 created fine porous structures, resulting in high catalytic activities of Ru/CeO 2 catalysts.

Nanoporous CeO 2 was prepared implementing the dealloying method on precursors consisting of CeAl alloys characterized by different atomic arrangements. In fact, the atomic arrangement of the precursor alloy strongly influence the surface area of CeO 2 in the final product. Nanoporous CeO 2 with quite high surface area were formed when an amorphous CeAl alloy was used as the precursor. The catalytic performance of the catalyst that Ni was supported on CeO 2 prepared from amorphous alloy were evaluated based on the reaction whereby molecular hydrogen is released from ammonia borane. A high level of catalytic activity was observed due to that fine Ni particles were dispersed on CeO 2 prepared from amorphous alloy with quite high surface area.

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