Structure Formation and Electrophysical Properties of Natural Zeolites, Mechanoactivated with Potassium Hydrophosphate for Obtaining Solid Electrolytes

Abstract

Mechanochemical activation of the impact-shear type of air-dry mixtures of clinoptilolite-stilbite and clinoptilolite rocks together with 25, 33, and 50 wt % potassium hydrogen phosphate trihydrate is carried out. The structure, phase, elemental, and granulometric composition, morphology, and physical properties of the powders are studied using infrared spectroscopy, differential scanning calorimetry, X-ray phase analysis, energy-dispersive X-ray spectrometry, sieve analysis, scanning electron microscopy, gravimetry, and air permeability. The electrical conductivity of tablet samples is measured in the temperature range from 25 to 580°C. It is found that the electrical conductivity of clinoptilolite-stilbite rock containing 50 wt % potassium hydrogen phosphate trihydrate, subjected to impact-shear action with the absorption of a mechanical energy dose of 5.04 kJ g^–1, is equal to 7.06 × 10^–2 S m^–1 at 560°C. It has been shown that mechanochemical activation of zeolite together with potassium hydrogen phosphate crystal hydrate contributes to an effective increase in conductivity and is a promising method for obtaining solid electrolytes.