Three-Dimensional MnCo 2 O 4.5 Mesoporous Networks as an Electrocatalyst for Oxygen Reduction Reaction

Abstract

© 2015 The Electrochemical Society. Developing highly active non-precious catalysts is still a great challenge for metal-air batteries. Herein, three-dimensional (3D) mesoporous MnCo 2 O 4.5 nanoflakes were fabricated via a facile two-step approach and proposed as a novel electrocatalyst for oxygen reduction reaction (ORR) for the first time. The as-prepared samples were well characterized by a combination of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and nitrogen absorption experiments. TheMnCo 2 O 4.5 nanoflakes have a relatively large surface area of 28 m 2 /g resulting from its 3D mesoporous networks. The electrocatalytic activity toward ORR was evaluated by linear sweep voltammetry tests, which indicated higher reduction current densities compared with Mn 3 O 4 and Co 3 O 4. It even outperformed the commercial carbon-supported Pt (5 wt%). The MnCo 2 O 4.5 with unique morphology here can be used as an efficient catalyst for metal/air batteries.