Catalytic Decomposition of H2O2on Co3O4Doped with Ag2O or ZnO

Abstract

The effects of doping Co3O4 with Ag2O (0.40-3.00 mol%) or ZnO (0.75-6.00 mol%) on the surface and catalytic properties of the solid were investigated via nitrogen adsorption at -196°C and the decomposition of H2O2 at 30-50°C. Pure and doped samples were prepared by the thermal decomposition in air at 500-900°C of pure cobalt carbonate and carbonate samples treated with different proportions of silver or zinc nitrates. The results showed that Ag2O doping followed by precalcination at 500-900°C resulted in a significant decrease (ca. 25%) in the BET surface areas of the treated Co3O4 samples. Treatment of Co3O4 with ZnO followed by precalcination over the same temperature range effected a corresponding increase in the specific surface areas (ca. 28%). The addition of Ag2O to Co3O4 effected a record increase in the corresponding catalytic activity towards the decomposition of H2O2. Thus, the maximum increase noted in the catalytic rate constant (k) measured at 30°C over Co3O4 doped with 3.00 mol% Ag2O exhibi...