TY - JOUR
T1 - Effect of sintering atmosphere on the pore-structure stability of cerium-doped nanostructured alumina
AU - Kumar, Krishnankutty-Nair P.
AU - Tranto, Janne
AU - Balagopal, N.
AU - Nair, Balagopal N.
AU - Kumar, Jalajakumari
AU - Hoj, Jacob W.
AU - Engell, John E.
PY - 1994
Y1 - 1994
N2 - Pore-structure stability of pure and Ce-doped alumina in air and argon atmospheres was studied using DTA, TGA, N2 ads./des. and XRD with a view to understand the importance of the ionic size of the dopant cation on the pore-structure stability of alumina. The ionic size effect was studied by heat treating the Ce-alumina system in both oxidizing and reducing atmospheres to have Ce4+ (87 pm) and Ce3+ (106 pm) respectively. No compound formation between Ce and alumina was observed. In the case of pure alumina there is a drastic reduction in porosity during the transformation to α-alumina. Ce-doped alumina has a higher DSC transformation temperature corresponding to the α-alumina transformation compared to pure alumina. Ce-doped alumina showed higher pore-structure stability compared with pure alumina and the stability was relatively higher in reducing atmosphere (higher Ce3+/Ce4+ ratio, higher effective ionic size) compared with oxidizing conditions (lower Ce3+/Ce4+ ratio, lower effective ionic size).
AB - Pore-structure stability of pure and Ce-doped alumina in air and argon atmospheres was studied using DTA, TGA, N2 ads./des. and XRD with a view to understand the importance of the ionic size of the dopant cation on the pore-structure stability of alumina. The ionic size effect was studied by heat treating the Ce-alumina system in both oxidizing and reducing atmospheres to have Ce4+ (87 pm) and Ce3+ (106 pm) respectively. No compound formation between Ce and alumina was observed. In the case of pure alumina there is a drastic reduction in porosity during the transformation to α-alumina. Ce-doped alumina has a higher DSC transformation temperature corresponding to the α-alumina transformation compared to pure alumina. Ce-doped alumina showed higher pore-structure stability compared with pure alumina and the stability was relatively higher in reducing atmosphere (higher Ce3+/Ce4+ ratio, higher effective ionic size) compared with oxidizing conditions (lower Ce3+/Ce4+ ratio, lower effective ionic size).
U2 - 10.1016/0025-5408(94)90045-0
DO - 10.1016/0025-5408(94)90045-0
M3 - Article
VL - 29
SP - 551
EP - 558
JO - Materials research bulletin
JF - Materials research bulletin
SN - 0025-5408
IS - 5
ER -