Perovskite La0.5Sr0.5CoO3−δ Grown on Ti3C2Tx MXene Nanosheets as Bifunctional Efficient Hybrid Catalysts for Li–Oxygen Batteries

Li–oxygen batteries (LOBs) have drawn widespread attention in the past decades. Herein, bifunctional hybrid catalysts based on perovskite La 0.5 Sr 0.5 CoO 3−δ with Ti 3 C 2 T x MXene nanosheets have been prepared for Li–oxygen batteries as effective catalysts. It is the first time using high Li ionic diffusion Ti 3 C 2 T x in Li–oxygen batteries system and making it, as substrate, in situ increase the high oxygen adsorption and O 2– transport perovskite La 0.5 Sr 0.5 CoO 3−δ . In this way, the hybrid catalysts show outstanding catalytic performance to facilitate the reaction kinetics, which display overpotential of only 0.87 V, lower than the Ti 3 C 2 T x by about 540 mV and La 0.5 Sr 0.5 CoO 3−δ by about 430 mV. The Li–oxygen batteries with LaSrCoO/Ti 3 C 2 T x electrodes run more than 80 cycles at 500 mA g – 1 with capacity restriction of 1000 mAh g – 1, much better than Ti 3 C 2 T x (9 cycles), La 0.5 Sr 0.5 CoO 3−δ (15 cycles), and other reported catalysts based on the perovskite. Moreover, the Li–oxygen batteries with LaSrCoO/Ti 3 C 2 T x electrodes deliver the highest initial discharge capacity of about 11 340 mAh g – 1 at 500 mA g – 1, which is about twice those of the LaSrCoO cathode (6700 mAh g – 1 ) and Ti 3 C 2 T x (5210 mAh g – 1 ). All the results suggest that the strategy would be a promising approach to enhance the performance of LOBs.