Spark Plasma Sintering and Hot Pressing of Hetero-Doped LaNbO4. - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Journal of the American Ceramic Society Année : 2012

Spark Plasma Sintering and Hot Pressing of Hetero-Doped LaNbO4.

Résumé

LaNbO4/La3NbO7 and LaNbO4/LaNb3O9 cer-cer composites were prepared by impregnating Ca-doped LaNbO4 powder, synthesized by spray pyrolysis, with La- or Nb-precursor solutions. The sintering of the calcined powders was investigated by dilatometry, and dense composites were prepared by conventional sintering, hot pressing, and spark plasma sintering. The particle size of the starting powders was about 50 nm, and the average grain size of the dense materials ranged from 100 nm and upwards, depending on the sintering temperature, sintering procedure, and the phase composition. The unit cell parameters of LaNbO4 showed a finite size effect and approached the cell parameters of tetragonal LaNbO4 with decreasing crystallite size, both for the single-phase material and the composites. The minority phase (La3NbO7 or LaNb3O9) were observed as isolated grains and accumulated at triple points and not along the grain boundaries, pointing to a large dihedral angle between the phases. The calcium-solubility in the minority phases was larger than in LaNbO4, which corresponds well with previous reports. The electrical conductivity of the heterodoped materials was similar to, or lower than, that for Ca-doped LaNbO4.

Domaines

Matériaux
Fichier principal
Vignette du fichier
Estournes_8706.pdf (2.82 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-03468686 , version 1 (07-12-2021)

Identifiants

Citer

Guttorm E. Syvertsen, Claude Estournès, Harald Fjeld, Reidar Haugsrud, Mari-Ann Einarsrud, et al.. Spark Plasma Sintering and Hot Pressing of Hetero-Doped LaNbO4.. Journal of the American Ceramic Society, 2012, 95 (5), pp.1563-1571. ⟨10.1111/j.1551-2916.2012.05101.x⟩. ⟨hal-03468686⟩
12 Consultations
30 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More