Improved Electrocatalytic Activity of Three-Dimensional Open-Structured Co<sub>3</sub>O<sub>4</sub>@MnO<sub>2</sub> Bifunctional Catalysts of Li-O<sub>2</sub> Batteries by Inducing the Oriented Growth of Li<sub>2</sub>O<sub>2</sub>
Jiajie Li, Heliang Zhou, Zhixu Jian, Honglei Li, Xianggang Guan, Yalan Xing, Shichao Zhang, Huaizhe Xu
Abstract
Rational structure and morphology design of catalytic cathode materials is the key to realize excellent performances of lithium-oxygen batteries (LOBs). Herein, a three-dimensional (3D) open-structured Co3O4@MnO2 heteromatrix has been designed through a facile two-step hydrothermal method. Unexpectedly, when it serves as oxygen reduction reaction/oxygen evolution reaction bifunctional catalytic cathodes for lithium-oxygen cells, the 3D open-structured Co3O4@MnO2 heteromatrix-catalyzed LOBs exhibit outstanding electrochemical performances (a high specific capacity of 12,980 mA h g–1 during the initial discharge and long cycle life of 331, 197, and 14 times with specific capacities fixed at 500, 1000, and even 3000 mA h g–1, respectively), obviously superior to reported batteries based on low-dimensional and closed-ended catalysts. We find that the enhanced electrochemical performances are ascribed to the bifunctional catalyst and the 3D open structure of the Co3O4@MnO2 heteromatrix, which can guide the homogeneous and fluffy deposition of discharge products Li2O2, demonstrating a promising application in both LOBs and flexible/wearable Li-air batteries.