Effect of FeB doping on the structural and electrochemical characteristics of MgNi alloy

FeB and MgNi-FeB composite were both prepared by mechanical alloying (MA) method. X-ray diffraction (XRD), scanning electron microscopy (SEM), charge-discharge cycles, Tafel polarization, electrochemical impedance spectroscopy (EIS), potentiostatic polarization and linear polarization were carried out to evaluate the effect of FeB on the structural and electrochemical characteristics of MgNi alloy. The results indicated that FeB doping improved the cycle stability of MgNi. The MgNi-FeB (weight ratio 100:15) composite which was MA 15 h exhibited the best electrochemical characteristics. After 100 charge-discharge cycles, the discharge capacity of this composite electrode was above 210 mA h g(-1), and the capacity retention was 60.62%, which was much higher than that of MgNi. FeB doping also improved the anticorrosion, the electrochemical kinetic properties and the high rate performance of MgNi. Crown Copyright (C) 2008 Published by Elsevier B.V. All rights reserved.