Synthesis and study of nanosized gadolinium oxide modified by zirconium oxide

Abstract

A method for the fabrication of nanosystems Gd2O3, 90%Gd2O3–10%ZrO2, 80%Gd2O3–20%ZrO2, 70%Gd2O3–30%ZrO2 from salt solutions using freeze-drying is studied. Using the TEM method, the particle sizes (18–40 nm) after annealing at 700 оС are estimated. In the Gd2O3–ZrO2 system the phases of Gd2O3 and Gd2Zr2O7 are present. The acid-base properties of the surface are evaluated using the Hammett indicator method: there are Brønsted acid sites with pKa = 1.7; 2.1; 3.46; 5.2 and the Brønsted base site with pKa = 7.4. The addition of zirconium oxide to gadolinium oxide sharply increases the value of specific adsorption and donor surface properties. Using DSC method, the process of acid-base catalysis as exemplified by thermodestruction of activated carbon in the presence of the systems Gd2O3, Gd2O3–ZrO2 is assessed. Decomposition of activated carbon in the presence of Gd2O3, 90%Gd2O3–10%ZrO2, 80% Gd2O3 -20%ZrO2, and 70%Gd2O3–30%ZrO2 proceeds faster. The activation energy of the processes decreases from 1.67 to 0.56 kJ/mol, while the thermal effect and mass loss increase.