α-MnO2 nanowire catalysts with ultra-high capacity and extremely low overpotential in lithium–air batteries through tailored surface arrangement

Abstract

We here report on very high capacity (11 000 mA h g⁻¹), superb rate capability (4500 mA h g⁻¹ at 5000 mA g⁻¹) and high reversibility of Li–air batteries using α-MnO₂ NW catalysts mainly associated with their relatively large amount of Mn³⁺ exposed on the NW surface and a unique mechanism for deposition of discharge products. Our findings of the unprecedentedly fast Li ion transport and reversible formation–decomposition of discharge products attributed to the modified surface arrangement of α-MnO₂ NWs suggest a strategy for achieving high-power Li–air batteries in combination with nano-architecture tailoring.