TRANSFORMATIONS OF MANGANESE OXIDES UNDER DIFFERENT THERMAL CONDITIONS

Thermal decomposition of various synthetic manganese oxides (MnO, Mn3O 4, Mn2O3, MnOOH) and a natural manganese dioxide (MnO2) from Gabon was studied with the help of termogravimetry in inert, oxidizing and redu cing atmospheres. The compounds were characterized by XRD and electroc hemical activity was tested by cyclic voltammetry using a carbon paste electrode. The natural manganese dioxide showed the best oxidizing an d reducing capacity, confirmed by the lower temperatures of the transi tions, the extent of the reactions and electrochemical performance in cyclic voltammograms.