Study of Cr2O3 nanoparticles supported on carbonaceous materials as catalysts for O2 reduction reaction

A series of chromium oxides (Cr2O3) nanoparticles supported on different carbonaceous material, namely: graphene, graphene oxide (GO) and graphite, were synthetized by precipitation the salt precursors with precipitant (ammonia) subsequent thermal treatment. The catalytic activity these composites Cr2O3 have been analysed Koutecky-Levich (KL) rotating ring-disc electrode methods results discussed following a model proposed here, which considers O2 electrosorption as rate determining step. Among them, graphite based better activities their behaviours agree treatment: logarithm dependent intercept nondependent slopes values KL plots potential. Cr2O3-graphite shows mechanism interchanging 4 e-, has attributed to graphite- interaction. Besides, Cr2O3-graphite-based electrodes tested cathode in Zn/PVA-KOH/air battery, confirming its good properties be applied positive metal-air batteries.