Rapid hydrogenation at 30 °c of magnesium (Mg) and iron (Fe) nanocomposite obtained through a decomposition of Mg2FeH6 precursor
M. Polanski , J. Bystrzycki , R.A. Varin , Tomasz Płociński
AbstractA ternary Mg2FeH6 hydride was synthesized applying the processing route described in detail in . Subsequently, a nanocomposite of 2Mg + Fe was produced through a thermal decomposition of Mg 2FeH6 precursor. Microstructural studies by SEM, STEM, EDS, EELS and XRD show a microstructure consisting of nanocrystalline nearly spherical Fe particles with an average diameter of 20-30 nm uniformly distributed in the nanocrystalline Mg matrix exhibiting the grain size on the order of 5-10 nm. The 2Mg + Fe nanocomposite was subsequently hydrogenated at 30 °C under 4 MPa of hydrogen pressure. After 10 h about 1.1 mass% of hydrogen has been absorbed but the pertinent desorption curve shows that the hydrogenation process is not saturated yet. Temperature programmed desorption (TPD) of hydrogenated 2 Mg + Fe sample shows an asymmetrical desorption peak with a tail extending from ∼130 to 200 °C, then sharp increase in the peak height and eventually a sudden drop around a maximum at ∼250 °C. This asymmetrical shape strongly suggests that a large population of nanocrystalline grains being in an intimate contact with the nanocrystalline particles of Fe which, most likely, act as a catalyst, is able to desorb hydrogen at very low temperatures from ∼130-250 °C under helium flow used in a TPD test. © 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.
|Journal series||International Journal of Hydrogen Energy, ISSN 0360-3199, (A 35 pkt)|
|Pages||1059 - 1065|
|Publication size in sheets||0.5|
|Keywords in English||Dehydrogenation; Hydrogenation at 30 °C; Magnesium-iron nanocomposite; Microstructure; Ternary Mg2FeH6 hydride|
|ASJC Classification||; ; ;|
|Publication indicators||= 17; = 16; : 2011 = 1.829; : 2011 = 4.054 (2) - 2011=4.402 (5)|
|Citation count*||17 (2020-01-31)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.