Electrical conductivity of solid solution of Co(II)-Zn dihydrophosphate and its thermolysis products

Abstract

Dependence of the specific electrical conductivity value of the solid solution with composition Co₁-xZnx(H₂PO₄)₂•H₂O(0 < x < 1.0) and products of its partial or complete dehydration from temperature and duration of heat treatment has been investigated. It has been established that they have considerable proton conductivity (from 1.01•10⁻⁰² - 1.18•10⁻² Ohm⁻¹cm⁻¹ to 7.51•10⁻³ - 9.57•10⁻³ Ohm⁻¹cm⁻¹) in a wide temperature range (80-270°C). The main contribution to their proton conductivity has made mobile protons of the phosphate anion P-OH groups and free phosphoric acid protons, which have produced in the intermediate thermolysis products according to PMR and ³¹P NMR spectrum analysis of Co(II)-Zn dihydrophosphates heat treatment products. Contribution of crystal water protons is minimal.