Thermal genesis, characterization, and electrical conductivity measurements of terbium oxide catalyst obtained from terbium acetate

Abstract

In this paper, the preparation and characterization of crystalline terbium oxide via thermal decomposition of acetate precursor is reported. The decomposition pathway of the parent salt was followed using TGA, DTA, and in situ electrical conductivity in air and nitrogen atmospheres. The obtained results indicated that, thermal decomposition of terbium acetate proceeded with the loss of water molecules, in two steps, below 150 °C followed by decomposition in the temperature range of 300–550 °C, throughout different intermediates, to give Tb 4O 7 as a final product. The calcination products, obtained by heating the parent salt for 3 h in air at various temperatures, were characterized using IR, XRD, SEM, nitrogen adsorption, and electrical conductivity measurements. It was demonstrated that Tb 4O 7 represents the major phase for the samples calcined at 600–900 °C. The role of Tb 3+–Tb 4+ redox couple in enhancing the electrical conductivity of the calcination products was also discussed.