Abstract:
Goan manganese ores, containing substantial amounts of Fe2O3 and SiO2 have been subjected to activation treatment using H2SO4 and HNO3 in varying concentration. The resulting oxides were characterised by chemical analyses, X-ray diffraction, and measurement of surface area. The discharge characteristics were evaluated in 9 M KOH solution. An attempt was made to correlate the structural features with the electrochemical activity. An explanation of the synergistic effect is given in the light of Ruetschi's cation vacancy model for manganese dioxides.
