|About this Abstract
||Materials Science & Technology 2012
||Nanotechnology for Energy, Environment, Healthcare and Industry
||Reactive Ball Milling Combined with Top-Down Approach for Synthesizing of Metastable Nanocrystalline MgH<2> Powders
||M. Sherif El-Eskandararny, Ayman Al-Qattan, Badriyah Al-Halaili, Doha Chehadeh, Maryam Saeed
|On-Site Speaker (Planned)
||M. Sherif El-Eskandararny
Pure Mg powders were ball milled under hydrogen gas pressure of 5 bar, using reactive ball milling (RBM) method. The progress of the RBM process was monitored by taking a small amount of the powders from the vial in an Ar glove box. All the sample powders were characterized as a function of the RBM time by means of XRD, FE-HRTEM, FE-SEM, image analyzer, DSC, hydrogen absorption/disrober spectrometer and temperature-programmed desorption mass spectrometry. The results have shown that a single phase of β-MgH2 nanocrystalline powders was formed after 25 h of RBM time. Increasing the RBM time leads to destabilize the formed β-phase, which tended to partially transform into a less stable phase of γ-MgH<2>. This phase transformation leads to improve the hydrogenation properties of the formed metal hydride powders, indexed by the hydrogenation/dehydrogenation temperatures (250°C – 350°C), hydrogen capacity (6.82 wt.% hydrogen) and the cycle-life-time (100 cycles).