Zirconia-Based Nanomaterials for Alternative Energy Application: Concept of Research in Smart Laboratory

The engineering of doped zirconia nanoparticles (NPs) for energy application is realized in concept Research Smart Laboratory. To improve nanomaterials’ engineering, correlations of “salt concentration—powder dispersity” and “calcined temperature—particle’s sizes” were built. The correlation of “materials structure—materials functionality” is made. The technology forming ceramics with varying grain sizes and densities under the same thermodynamic conditions (1350 °C) from NPs with different sizes is developed. The impedance spectroscopy with the distribution of relaxation time analysis is used for ionic conductivity ceramic investigation in range 240–900 °C. The activation energies of the grain and grain boundary oxygen diffusion are calculated. It was shown that the energy activation of bulk oxygen diffusion does not depend on ceramic grain size (E_a = 0.9 eV). The energies activation of grain boundary oxygen diffusion estimated in the framework of the bricklayer model show a weak growth with the rising of ceramic grains sizes. The values of the volume activation energy are close to the grain-boundary activation energy for ceramics obtained from nanoparticles smaller than 18 nm. It was found that the grain boundary space contains two types of elements with different geometries. The size of NPs used for ceramic determines the size of grain boundaries elements. It was shown that the density of sintered ceramic has a more substantial effect on its electrophysical properties than grain size. The NPs sizes of 18–24 nm are optimal for forming pressed powder compacts and sintered ceramics with high density.