One-pot fabrication of yolk–shell structured La0.9Sr0.1CoO3 perovskite microspheres with enhanced catalytic activities for oxygen reduction and evolution reactions

Abstract

Efficient electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) play a critical role in the performance of fuel cells and metal–air batteries. In this work, we report a one-pot fabrication pathway to prepare yolk–shell structured La_0.9Sr_0.1CoO₃ perovskite microspheres as highly active electrocatalysts for the ORR. The shell number could be controlled by using different solvents. Compared with regular La_0.9Sr_0.1CoO₃ particles, yolk–shell structured La_0.9Sr_0.1CoO₃ oxides have larger specific surface area. Catalytic activities of the as-prepared catalysts for the ORR and OER in 0.1 M KOH media have been studied by using a rotating ring-disk electrode (RRDE) technique. RRDE results show that multi-shelled La_0.9Sr_0.1CoO₃ exhibits better catalytic activity for the ORR and OER with durabilities superior to commercial Pt/C catalysts.