International Journal of Hydrogen Energy, Vol.36, No.1, 1177-1183, 2011
The composites of magnesium hydride and iron-titanium intermetallic
Hydride-intermetallic composites MgH2 + X wt.% FeTi (X = 10, 30, 50) were synthesized by Controlled Mechanical Milling (CMM) in a magneto-mill. Their thermal behavior was investigated by Differential Scanning Calorimetry (DSC) and Temperature Programmed Desorption (TPD). It is found that the DSC hydrogen desorption peak temperature as well as the activation energy of hydrogen desorption of the MgH2 constituent in composites decreases linearly with increasing volume fraction of FeTi with a coefficient of fit R-2 = 0.98. A doping of the MgH2 + FeTi composites with 5 wt.% of nanometric-size nickel (n-Ni) produced by Vale Inco Ltd. further reduces the DSC hydrogen desorption peak temperature of MgH2 to the temperature range below 300 degrees C for the MgH2 + 10 and 30 wt.% FeTi composites. The most effective reduction of the DSC hydrogen desorption peak temperature of the MgH2 constituent by as much as 60 degrees C due to the catalytic effect of n-Ni is observed for the MgH2 + 10 wt.% FeTi + 5 wt.% n-Ni composite. At this composition the composite also has hydrogen capacity slightly higher than 5 wt.%. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.
Keywords:Solid state hydrogen storage;Desorption temperature and kinetics;Nano-nickel additives;Hydrogen storage materials;Composite hydrides MgH2 and FeTi;Ball milling