ADVANCES IN THE ACTIVATION OF CARBON ELECTRODES FOR OXYGEN REDUCTION

摘要

Oxygen reduction was studied on Co_3O_4-based electrocatalysts obtained by thermal decomposition at 400℃ of such different precursors as Co nitrate, oxalate, citrate and carbonate. The oxide was deposited on a Ni support either directly or mixed with carbon by means of a binder (Nafion). Electrodes were characterized by XRD, TEM, BET, CV and potentiostatic curves. Co_3O_4 from carbonate resulted the most active material but its activity was still poorer than that of pyrolyzed CoTMPP thus far recommended as the most active electrocatalyst. If Co_3O_4 is obtained by pyrolysis at much higher temperature of Co carbonate in the presence of TMPP alone, the resulting material is appreciably more active than pyrolyzed CoTMPP.