|
|
|
|
The magnetic and structural properties of Ni fine particles coated with Pd were investigated by means of magnetometry and X-ray diffractometry in a hydrogen atmosphere, to study the magnetic and structural changes resulting from hydrogenation. The average particle of Ni is 0.7 mm in diameter, and the thickness of the Pd shell is from 5 nm to 37 nm. The lattice of hydrogenated Pd is expanded, and the degree of this expansion decreases with decreasing thickness of the Pd shell. The Pd shell is magnetically polarized by the exchange enhancement at the interface between the Ni core and the Pd shell. The Pd shell is magnetically polarized below 80 K, and is slightly polarized even at room temperature. The hydrogenation of Pd suppresses the magnetic polarization and the interface magnetic anisotropy.