Effect of Al, Fe Addition on Thermodynamic Stability and Hydrogen Desorption KInetics from MgH2 Phase OF Mechanical Alloy

• Main Authors: О. G. Еrshova, V. D. Dobrovolsky, Yu. М. Solonin, A. Yu. Koval
• Format: Article
• Language: English
• Published: Vasyl Stefanyk Precarpathian National University 2016-10-01
• Series: Фізика і хімія твердого тіла
• Online Access: http://journals.pu.if.ua/index.php/pcss/article/view/800
• ISSN: 1729-4428; 2309-8589

<p class="ArticleAnnotation">With the aim of lowering the temperature, improve the kinetics of the decomposition of stoichiometric hydride MgH₂was investigated the possibility of its complex doping Al, Fe using mechanochemical synthesis (RMS). The MA1 sample was derived by reactive milling  Mg + 10 wt% Al + 10 wt. % Fe powder mixture in the hydrogen atmosphere at pressure of 1.2 MPa in a reactor for 10 h. The formation (in conditions of mechanochemical synthesis) of hydride of solid solution of Al and Fe in magnesium Mg(Al,Fe)H₂ was experimentally checked. Found that adding to magnesium Al &amp; Fe leads to lower of thermodynamic stability<strong> </strong>and, consequently, to lower the temperature of the beginning of desorption of hydrogen to 250 ⁰C at 0,1MPa H₂ (compared to MgH₂ without Al and Fe). After the first cycles of hydrogenation-dehydrogenation from gas phase MA, established by isobaric thermal desorption spectroscopy, the effect of lowering the temperature of the beginning desorbtion 315 ⁰C (for non-alloy phase MgH2) to 250 ⁰C was observed. Adding to magnesium aluminum with Fe significantly improves the kinetics of desorption of hydrogen from the hydride phase MgH₂ mechanical alloy produced by RMS.</p>