Highly active Co-doped LaMnO3 perovskite oxide and N-doped carbon nanotube hybrid bi-functional catalyst for rechargeable zinc-air batteries

Herein, non-precious cobalt doped lanthanum manganese perovskite oxide nanoparticles are used as a growth substrate for nitrogen-doped carbon nanotubes to form efficient and durable hybrid hi-functional catalyst (LMCO/NCNT). LMCO/NCNT demonstrates significantly enhanced onset and half-wave oxygen reduction reaction (ORR) potentials (-0.11 and -0.24 V vs. SCE, respectively), and oxygen evolution reaction (OER) current density (27 mA cm(-2) at 0.9 V vs. SCE). Likewise, practical rechargeable zinc-air battery testing using atmospheric air reveals superior discharge voltages obtained with LMCO/NCNT, particularly at current densities higher than 30 mA cm(-2), and significantly lower charge voltages at all current densities tested, compared to state-of-art commercial platinum on carbon catalyst In addition, very stable charge and discharge voltages of 2.2 and 1.0 V, respectively, are obtained over 60 cycles. The excellent performance and durability of the hybrid catalyst are attributed to very uniformly distributed LMCO nanopartides on the surface of NCNT resulting in enhanced surface area and material utilization. (C) 2015 Elsevier B.V. All rights reserved.