Cobalt oxide spinel electrodes for oxygen reduction reaction in alkaline medium

Abstract

The kinetics of the oxygen reduction reaction (ORR) was studied on Co3O4/C electrodes in KOH electrolyte by using cyclic voltammetry and steady state polarization measurements using the Hg/HgO as the reference electrode. The morphological features of the materials were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD) & BET surface area. The electrodes were prepared by dispersing Co3O4 on vulcan carbon in situ and manually grinding the same. Co3O4 showed nanocrystalline nature and surface area was found to increase on dispersing with vulcan carbon by manually grinding in pestle and mortar. The polarization results showed higher electrocatlytic activity for the ORR on Co3O4/C (G) materials in comparison to Co3O4/C (P) prepared by dispering Co3O4 on a vulcan carbon. Electrocatalytic activity of N(G) & N(P) were compared with Pt/C electrodes.