Perovskite-type NdNiO3-y and Nd0.9Y0.1NiO3-y were prepared by healing the gel-derived powders at 700 °C in flowing oxygen or in air for relatively short heating time of 20 h, and the lattice constants, oxygen content, valence state of Ni ions and temperature dependence of the electrical resistance were measured. A new oxygen-deficient orthorhombic phase NdNiO3-y was found, which has larger lattice constants and lower metal-semiconductor (M-S) transition temperature than the previously known NdNiO3 phase. By substituting Y for Nd in the present NdNiO3-y, the lattice constants all decreased and the M-S transition temperature increased from 130 to 240 K. The changes in the lattice constants and the M-S transition were discussed in terms of the ionic radius and the electronic bandwidth, respectively.
|Number of pages||5|
|Journal||Nippon Seramikkusu Kyokai Gakujutsu Ronbunshi/Journal of the Ceramic Society of Japan|
|Publication status||Published - 1994|
ASJC Scopus subject areas
- Ceramics and Composites
- Condensed Matter Physics
- Materials Chemistry