Nanocomposites and nanomaterials

Effect of the synthesis temperature on the electrophysical properties of zirconia nanoparticles 
Shylo A.1, Danilenko I.1, Gorban O.1, Lyubchyk A.2,3

1 Materials Science Department, Donetsk Institute for Physics and Engineering named after O.O. Galkin of the NAS of Ukraine, Nauki ave, 46, Kyiv-03028, Ukraine,  e-mail:art.shylo@gmail.com
2 NANOTECHCENTER ,Kyiv, Ukraine
3 Lusófona University, Lisbon, Portugal

The work is devoted to investigation of the evolution of an adsorbed water layer on the surface of zirconia nanoparticles with different synthesis temperatures and its effect on the electrophysical properties of compacted zirconia nanoparticles. The combination of methods used in this work allowed to analyze the structure of the hydrated shell of zirconia nanoparticles and to determine the relationship between the structure of the adsorbed layer on the surface of zirconia nanoparticles and the electrophysical properties of compacted hydrated zirconia nanoparticles with different synthesis temperatures.
Thus, the DSC method shows that the water in the adsorption layer has a different degree of connectivity, as indicated by several temperature ranges of water desorption on the surface of nanoparticles with different activation energies. It is shown that the activation energy of water desorption from the surface of zirconia nanoparticles increases by 25% for all temperature ranges with increasing nanoparticles synthesis temperature.
The distribution relaxation time was successfully demonstrated in the analysis of the impedance spectra of compacted zirconia nanoparticles. DRT was then applied to the spectra and polarization losses were separated based on their typical time constants. The EIS method shows that the electrophysical properties of compacted nanoparticles depend on their annealing temperature. This can be explained by the different type of ordering of some structural elements in the system of nanoparticles, the size of the nanoparticles and the structure of the adsorbed layer on their surface.
ACKNOWLEDGMENTS
The authors are thankful the H2020-MSCA-RISE-2019 Program, project 871284 SSHARE for support of this work.