Nanostructured copper–cobalt based spinel for the electrocatalytic H₂O₂ reduction reaction

Nanostructured copper–cobalt based spinel [(Cu_0.30Co_0.70)Co₂O₄] was employed as an electrocatalyst in the hydrogen peroxide (H₂O₂) reduction reaction (HRR). Both nanoparticles and nanoneedles co-existed in the (Cu_0.30Co_0.70)Co₂O₄ spinel, which exhibited a high intrinsic electrical conductivity and surface-to-volume ratio, resulting therefore in a large electrochemically active surface area for the HRR. In addition, (Cu_0.30Co_0.70)Co₂O₄ showed an onset potential at approximately −0.14 V in the HRR, with a limiting current density of ∼104 mA/cm² at −0.43 V. The synthesised material followed the direct HRR pathway and exhibited good stability. In addition, the HRR activity of (Cu_0.30Co_0.70)Co₂O₄ was comparable to that of commercial Pt/C electrodes. The present results therefore demonstrate the significant potential of (Cu_0.30Co_0.70)Co₂O₄ for future applications in fuel cells as a cathode catalyst.