Synthesis, thermal characterization and local structure studies of Gd doped Th0.7U0.3O2 using X-ray absorption spectroscopyElectronic supplementary information (ESI) available. See DOI: 10.1039/c6ra07621a

• Main Authors: Pai, Rajesh V, Bamankar, Y. R, Yadav, A. K, Bhattacharyya, D, Jha, S. N, Kasar, U. M, Krishnan, K, Sali, S. K, Radhakrishna, J
• Format: Journal Article
• Published: 01.07.2016
• ISSN: 2046-2069
• DOI: 10.1039/c6ra07621a

(Th 0.7− x U 0.3 Gd x )O 2+ y microspheres where x = 0, 0.05, 0.10 and 0.15 were prepared by internal gelation method. Good quality translucent microspheres of size ∼1.70 to 2.0 mm were obtained when low metal ([M]) and high [hexamethylenetetramine + urea]/[M] ( R ) concentration was used. The solid solutions prepared from these microspheres were subjected to thermal expansion studies which showed a gradual decrease in thermal expansion coefficient values with increase in Gd ion concentration. Specific heat capacities of mixed oxides were measured from 300 to 850 K and showed that the temperature dependence of the heat capacities of Gd doped samples is similar to that of the un-doped sample. The local structure studies by EXAFS showed that Gd-O, Gd-Th and longer Gd-O paths are similar to Th-O, Th-Th and longer Th-O path lengths. EXAFS studies showed higher oxygen coordination in the case of the 10% Gd substituted sample compared to the other samples. (Th 0.7− x U 0.3 Gd x )O 2+ y microspheres where x = 0, 0.05, 0.10 and 0.15 were prepared by internal gelation method.