Sintering of Ce, Sm, and Pr Oxide Nanorods

Synthesis of CeO 2 , Pr 2 O 3 , and Sm 2 O 3 nanorods and their sintering have been investigated. In a strongly alkaline medium, nanorods of CeO 2 , Pr 2 O 3 , and Sm 2 O 3 were prepared from trivalent salts of rare earths (Ce, Pr, Sm) via precipitation synthesis. Nanorods were formed by nanocrystallites of fibrous structure, which were produced by the mechanism of self‐arrangement of hexagonal particles of Re( III ) hydroxides. The subsequent transformation of hydroxide into oxide proceeded via self‐preservation of the rod‐like structure. In CeO 2 , the fibrous structure was noncohesive during thermal treatment at temperature of 500°C and higher. Regardless of the shape of the CeO 2 particles (spherical versus rod‐like), sintered ceramic was formed by equiaxial grains. The cohesion of the fibrous structure of Pr and Sm oxides was higher than in CeO 2 . The rod‐like shape of the particles of Pr and Sm oxides was (partially) preserved during sintering.