Investigation of Raman spectra and ionic conductivity of composites based on NaClO4 and KClO4 salts obtained by mechanoactivation

Abstract

The work is aimed at studying the effect of mechanical activation on the structure and electrical conductivity of the NaClO4 – and KClO4 – basedcomposites. Based on the result of the analysis of the DSC curves of the (1–x) NaClO4 – x Al2O3 and (1–x) KClO4 – x Al2O3 composites measured while heating and cooling the samples, it was established that the enthalpy of phase transitions in them decreased with an increase in the concentration of the nanosized dopant. A complication of all active vibrational contours corresponding to internal vibrations of the molecular anion in the composites with increasing Al2O3 concentration and a shift of the band of the fully symmetric stretching vibration v1 (A) to a low-frequency region was revealed by Raman spectroscopy. Based on electrochemical impedance spectroscopy data, it was determined that for the 0.4NaClO4 – 0.6Al2O3 system subjected to mechanoactivation, the values of specific ionic conductivity increased by two orders of magnitude as compared to that of pure NaClO4, while for the 0.4KClO4 – 0.6Al2O3 system, the values of specific ionic conductivity increased by three orders of magnitude as compared to the initial salt at T = 320 °C.