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Nanopowders based on zirconia due to their high dispersion are prone to adsorption of water from the surrounding atmosphere and formation a layer of adsorbed water on the surface of nanoparticles. Therefore, taking into account the processes of formation of adsorbed layers of water on the surface of nanoparticles in real atmospheric conditions, their structure and characteristics, as well as their impact on the structure and electrophysical properties of zirconia nanoparticles are very interesting. The influence of the degree of hydration on the electrophysical properties of compacted hydrated nanoparticles of zirconia was investigated and a quantitative layer-by-layer model of the hydrated particle was constructed, the number and order of adsorbed water layers on the surface of nanoparticles at different ambient humidity were determined. The presence of three relaxation processes in the system nanoparticle – adsorbed water layer was established, which indicates different mobility of water molecules in the adsorbed layer and corresponds to its three components - Stern layer, diffuse layer and free water layer in the space between particles. Increasing the degree of hydration of the compacted powder from zero to the most water-saturated leads to sequential filling of the adsorbed layer on nanoparticles, which leads to an increase in electrical capacity of the respective components of the adsorbed layer for the Stern layer in 13 times and for the free water layer in 15 times. Based on the known model of the structure of the electric double layer and obtained data, the parameters of the electric double layer of nanoparticles was calculated.

The work is devoted to the investigation of the electrophysical properties of nanopowder systems based on zirconia in a compacted form with varying degree of system hydration. The dependence of conductivity and activation energy of conduc- tivity on the amount of moisture in the system was studied. It is shown that the value of the total impedance of the system decreases by 55 times as the amount of moisture in the system increases from minimum to maximum. The main contribution to conductivity is made by di✇usion processes in the space between nanoparticles. The possibility of using this e✇ect to characterize the thermodynamic environmental conditions, in which the system is located, is shown.

A technique for studying of electrical characteristics based on electrochemical impedance spectroscopy of sealed nanopowder compact sets from a powder based on ZrO2 was proposed. The possibility of using this technique for studying of influence of pulsed magnetic field on a charge state of the surface of zirconia nanoparticles is shown. It is established that the action of a weak pulsed magnetic field leads to redistribution of free charge carriers between the volume and the surface of nanoparticles. In particular, different processing times lead to different impedance behaviour: treatment of a pulsed magnetic field with a pulse repetition frequency f = 1 Hz and an exposure time t nanoparticle surface by two times (from 3.47 • 10-5 to 1.72 • 10-5 Ohm-1 • m-1), and processing with exposure time 15 causes formation in the near-surface zone of nanoparticles of a region depleted of charge carriers.