A mechano-chemical activation synthesis (MCAS) is employed to fabricate Mg(AlH 4) 2 via milling the precursors, specifically NaAlH 4 and MgCl 2. The corresponding dehydrogenation behavior of the synthesized powders is investigated. The experimental results showed that incomplete synthesis or premature dehydrogenation may occur if the milling process was not properly controlled. The hydrogen content of each synthesized powder is determined by using a thermal gravimetric analyzer (TGA). The dehydrogenation reactions of the synthesized powders are investigated by employing ex situ X-ray diffraction (XRD), in situ synchrotron XRD and differential thermal analysis (DTA). The results showed that the incompletely synthesized powder consisted of residual NaAlH 4 in the synthesized Mg(AlH 4) 2, which demonstrated an initial dehydrogenation temperature as low as 100 °C and accompanied with a maximum amount (3.1 wt%) of H 2 released below 350 °C. The mutual catalytic effect of both NaAlH 4 and Mg(AlH 4) 2 on lowering their initial dehydrogenation temperature is confirmed.
All Science Journal Classification (ASJC) codes
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry