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Magnesium and Magnesium-based alloys are considered to be promising storage media because of their hydrogen storage capacity (7.66wt.% for pure Mg), low density, low cost and high availability. However, commercial application of the magnesium hydride currently inhabited by its high absorption/desorption temperature, poor reaction kinetics, high oxidation reactivity [1]. To overcome these disadvantages, many researchers studied techniques such as catalysing, nanostructuring and alloying. Furthermore, milling used as a hydrogen storage material has positive effects on hydrogenation behavior because a high surface area can be obtained by milling [2]. A few studies were conducted for MgH_x intermixed with fluoride. Yavari et al. and Ma et al. reported that MgF₂ formed from the MgH_x-transition metal fluorides system can be replaces the initial surface oxide later and provides a reactive and protective fluorinated surface for hydrogen uptake. Thus the absorption/desorption kinetics will be enhanced [3, 4]. In this research, the MgH_x-CeF₃ has been prepared by planetary ball milling under argon atmosphere. MgH_x containing 5 and 10 Vol.% of fluoride was charged with 17.7mm diameter Cr-steel ball into BPR 66:1. The powders synthesized were characterized by XRD, SEM, EDS, BET and simultaneous TG/DSC analysis. The hydrogenation behaviors were measured by using Sievert’s type automatic Pressure-Composition-Temperature (PCT) apparatus. The results of XRD patterns indicated that MgH_x-CeF₃ composites contain MgH₂, CeH₂, CeF₃ and MgF₂ respectively, after milling for 96hours. SEM observation revealed that MgH_x-CeF₃ composites has both small and large particle with file particles on their surfaces. EDS image mapping of MgH_x-CeF₃ composites shown that, each element is distributed homogeneously. The specific surface area of MgH_x was 1.547m²/g, that of MgH_x-5, 10Vol.% CeF₃ was 6.336, 4.969m²/g. respectively.

Hydrogen storage materials; Non-activation treatment; Mg hydrides; MgHx-CeF3 composites; Planetary ball milling