Abstract
The work is devoted to the study of optical and thermophysical properties of promising materials for nuclear power of a new generation - inert matrices of nuclear dispersed fuel based on ZrO2 – CeO2 (ZCO) doped with Y2O3. Interest in this class of materials is due to great prospects in the field of replacing the traditional type of nuclear fuel with uranium-free dispersed nuclear fuel, which is based on a technological solution using plutonium as a fissile element, placed in a dispersed inert matrix based on oxide or nitride ceramics. The purpose of this work is to study the effect of doping of ZCO ceramics with Y2O3 on the optical and heat-conducting properties. During the study, it was found that an increase in the concentration of the Y2O3 dopant leads to the formation of a highly ordered CeZrO4 phase, the presence of which leads to the appearance of an additional absorption band in the region of 550 – 650 nm, as well as a decrease in the transmission value in the region of 400 – 700 nm. To evaluate the results obtained, the methods of optical UV spectroscopy and heat flux determination were applied. It has been found that doping with Y2O3 leads to the formation of a highly ordered CeZrO4 phase, the formation of which leads to the appearance of additional spectral absorption lines, as well as a shift in the band gap to the region of low energies. During analysis of the thermophysical parameters, it was found that a change in the phase composition leads to an increase in the thermal conductivity coefficient by more than 40 – 60 %.