English
РусскийInfluence of synthesis conditions on electrophysical properties of layered potassium polytitanates
The influence of the pH value in the dispersions during washing the potassium polytitanate powder (PPT) after its molten salt synthesis on electrical properties of the obtained product, namely conductivity, permittivity and tangent of dielectric losses. It is established that the samples obtained in weakly alkaline conditions (pH = 7.44 and 8.50), are characterized by higher values of low-frequency conductivity and dielectric permittivity (up to 10^{5), low value of the relaxation time (0.112 and 0.358, respectively). The differences of the studied objects are considered as a result of the changes in their chemical composition depending on acidity of the medium during synthesis, primarily caused by ion-exchange of potassium cations located in the interlayer space of the PPT with hydronium ions from aqueous solution. In the high frequency range, where the nature of conductivity is determined by electron structure of the PPT polyanions, the electrical properties of the obtained are practically independent on washing conditions.
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