Investigation of the percolation threshold of electrical properties in hydrated YSZ –nanopowder systems

The features of hydrated nanopowder system transition from non-conducting state to state with final conductivity are interesting for power nanoelectronics. The purpose of this work is to study the hydrated nanopowder systems of YSZ composition in strong electric field. The powders of ZrO2 - 3% mol Y2O3 (YSZ) composition which was obtained by the method of co-precipitation followed by annealing at temperatures from 400°, 500° and 600°C were used. The laboratory models of nanopowder humidity sensors in the form of polymer films filled with nanosized YSZ crystallites were obtained by applying a powder slurry in 4% PVA solution in water to dielectric substrates with silver electrodes. The distance between the electrodes was 2 mm. The dependence of electrical resistance to humidity at the samples was recorded by using a universal measuring device VC9808 in voltage range up to 1000V. Humidity was controlled by using of the salts in the range of 60-75%. It has been found that the process of percolation of electrical conductivity in systems with particle size of 7.5nm (annealing at 400°C) in the electric field up to 400V/mm has an extreme non-monotonic character. It has been found that the feature is reduced by increasing particle size