Preparation and Electrochemical Performance of Co-Fe/C for Bi-Functional Air Electrode

Cobalt and iron composite deposited on Carbon (Vulcan XC72) was prepared by microwave heating reduction method. The structure and morphologies were characterized by X-ray diffraction and scanning electron microscopy. The prepared Co-Fe/C showed good catalytic activity for both oxygen reduction reaction (ORB.) and oxygen evolution reaction (OER) in 6 M KOH. Electrochemical ac impedance measurements were used to study the mechanism of ORB. and OER on the Co-Fe/C electrode. It was found that the mechanism of ORR on the electrode with Co-Fe/C was similar to that on Pt electrode in alkaline solution's. A zinc-air battery using Co-Fe/C as catalyst on air electrode was set up and ran in 6 M KOH at room temperature for 118 hours with good stability. The discharge voltage around 1.0 V and the charge voltage of lower than 2.15 V, were obtained. (C) 2013 The Electrochemical Society. All rights reserved.