Layered perovskite oxide PrBaCo2O5+δ as a potential cathode for lithium–oxygen batteries: High-performance bi-functional electrocatalysts

Herein, a new type of perovskite oxide PrBaCo2O5+δ was synthesized and innovatively applied into Li-O2 battery (LOB) system as a cathode catalyst, obtained a specific capacity of over 8000 mAh g−1 and sustained more than 1000 cycles at a fixed capacity of 1000 mAh g−1, the number of which approaches and even exceeds most carbon-based Li-O2 batteries. The charge transfer resistance (Rct) was tested and resulted in 71 Ω, which was obvious lower than that of BP2000, i.e., 145 Ω. The charging voltage of the PBCO cathode was less than 4 V, resulting in substantially enhanced voltage and energy efficiencies. All these results demonstrated that PrBaCo2O5+δ can be a potential bi-functional catalyst in LOB systems.