Synthesis of α-MnO₂ Nanowires via Facile Hydrothermal Method and Their Application in Li-O₂ Battery

Li-O₂ batteries are regarded as a promising energy storage system for their extremely high energy density. MnO₂-based materials are recognized as efficient and low-cost catalyst for a Li-O₂ battery positive electrode material. In this work, α-MnO₂ nanowires were successfully synthesized by a hydrothermal method and their electrocatalytic performance were investigated in Li-O₂ batteries. X-ray diffraction and field emission scanning electron microscope confirms the formation of α-MnO₂. The Li-O₂ battery which consists of α-MnO₂ nanowires shows a high discharge capacity up to 12000 mAh∙g^-1 at a restrict voltage of 2.0 V with the current density of 100 mA∙g^-1. When restricting the discharge capacity at 500 mAh∙g^-1, it can operate over 40 cycles and exhibit good cycle stability. These results in¬dicate that the α-MnO₂ nanowires can be used as positive electrode catalysts for Li-O₂ batteries.