Sorption behavior of the Mg-Fe-H hydrogen storage system

J. A. PUSZKIEL; F. C. GENNARI; P. ARNEODO LAROCHETTE; FAHIM KARIMI; C. PISTIDDA; RAPEE GOSALAWITUTKE; JULIAN JEPSEN; JOSÉ BELLOSTA VON COLBE; THOMAS KLASSEN; MARTIN DORNHEIM

Kyoto

Simposio; Symposium on Metal Hydrogen Systems 2012-MH2012; 2012

Metal-Hydrogen Systems 2012

Due to the highest known volumetric hydrogen density (150 kg H2.m-3) and agravimetric hydrogen density of 5.4 wt%, Mg2FeH6 is considered a promising materialfor hydrogen storage. However, because of the absence of intermetallic compoundsbetween Mg and Fe [1], pure Mg2FeH6 is difficult to synthesize.Hydrogen sorption behavior of the Mg-Fe-H system is investigated via synchrotronXRD, DSC and volumetric techniques. Results show that a 2Mg-Fe stoichiometricmixture can not be totally hydrided, a Mg2FeH6-MgH2 hydride mixture is obtainedinstead. Upon hydriding MgH2 is a precursor for Mg2FeH6 (Fig. 1 A). Upon dehydridingMgH2 and Mg2FeH6 decompose independently. The composition and sorption kineticbehavior of the Mg-Fe-H system depends on the temperature and pressure conditions(Fig. 1 B).