Hydriding properties of nanocrystalline Mg2-xMxNi alloys synthesized by mechanical alloying (M = Mn, Al)

The nanocrystalline Mg-based hydrogen storage, Mg2-xMxNi (M = Mn, Al and x = 0, 0.25, 0.5), alloys have been synthesized by mechanical alloying followed by annealing (450degreesC/0.5 h). The structure of these materials have been examined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Thermodynamic and electrochemical properties have also been investigated. The hydrogen content of synthesized alloys is decreased compared to Mn-, Al-free Mg2Ni material. On the other hand, substituted nanocrystalline Mg-based alloys show substantially enhanced discharge capacity, at room temperature. (C) 2003 Elsevier B.V. All rights reserved.