Ba0.95La0.05FeO3−δ–multi-layer graphene as a low-cost and synergistic catalyst for oxygen evolution reaction

Oxygen evolution reaction (OER) is critical to many important energy conversion and storage processes. However, the kinetics of OER is typically sluggish, and conventional OER catalysts are scarce and expensive. Hence, inexpensive and effective catalysts that accelerate the OER kinetics and reduce the overpotential are urgently needed. In this paper, we reported multi-layer graphene-supported perovskite Ba0.95La0.05FeO3−δ (BLF–MLG) as a highly active OER catalyst. Electrochemical results showed that the BLF–MLG hybrid exhibited a high current density (∼23 mA/cm2 at 0.60 V vs. mercury/mercury oxide electrode (MMO)) and a more negative onset potential (∼0.43 V vs. MMO). Furthermore, the hybrid showed a smaller Tafel slope (77 mV/decade) and improved long-term stability. The remarkable OER performance is mainly attributed to the synergistic effect between BLF and graphene.