Sm0.5Sr0.5CoO3−δ – A new bi-functional catalyst for rechargeable metal-air battery applications

Sm0.5Sr0.5CoO3−δ (SSC) was evaluated as a bi-functional catalyst for rechargeable metal-air battery cathodes. The catalyst was homogenously dispersed on corrosion-resistant graphitized Vulcan XC-72R carbon powder for the cathode fabrication. For comparison, the air cathode catalyzed with the widely studied perovskite La0.6Ca0.4CoO3 (LCC) was included in the evaluation. Based on the polarization curves, SSC exhibited similar catalytic activities as LCC for both oxygen evolution reaction and oxygen reduction reaction. Furthermore, the air cathode prepared with SSC exhibited an improved cyclic life. These results suggest that SSC is a promising alternative to LCC as a bi-functional catalyst for metal-air battery cathode applications.

► Sm0.5Sr0.5CoO3−δ (SSC) was proposed and evaluated as a new bifunctional catalyst.
► SSC and La0.6Ca0.4CoO3 (LCC) catalysts had similar electrochemical performance.
► The SSC electrodes had a longer lifetime over the LCC electrodes.
► The degradation mechanisms were different for these two electrodes.