Thermoelectrical and thermal analyses of copper(II) acetate monohydrate ZnO–matrix composite powder obtained by freeze-drying

The thermal history of freeze-dried mixtures of composite powders containing ZnO–matrix and (CH3COO)2Cu·H2O (copper(II) acetate monohydrate) was undertaken by thermal analysis (TA) coupled to thermoelectrical analysis (TEA). Experiments were carried out on compacted samples, under non-isothermal conditions, in air, up to 350 °C, by measuring the electrical resistance during heating, called thermoelectrical resistometry (TER), and by differential scanning calorimetry (DSC). Activation energy (Ea) for exothermal events related to the decomposition of (CH3COO)2Cu (copper(II) acetate, CuAc2), observed within the range 225–325 °C, was estimated according to ASTM E 698 method. Values of Ea equal to 154 and 155 kJ/mol were obtained by TER and DSC, respectively. TER showed that the thermal decomposition of CuAc2 involves the liberation of electrons. Results also indicated that TER may be used as an alternative or complementary method for the study of the thermal decomposition mechanisms of transition metal(II) acetates.