Hydrogen Storage Properties of Magnesium Base Nanostructured Composite Materials

Journal Article · Fri Apr 30 04:00:00 EDT 2004 · Journal of Alloys and Compounds

OSTI ID:823470

AU, M

In this work, nanostructured composite materials have been synthesized using the mechanical alloying process. The new materials produced have been investigated by X-ray diffraction (XRD), transition electron microscope (TEM), scanning electron microscope (SEM) and electron energy dispersion spectrum (EDS) for their phase compositions, crystal structure, grain size, particle morphology and the distribution of catalyst element. Hydrogen storage capacities and the hydriding-dehydriding kinetics of the new materials have been measured at different temperatures using a Sieverts apparatus. It is observed that mechanical alloying accelerates the hydrogenation kinetics of the magnesium based materials at low temperature, but a high temperature must be provided to release the absorbed hydrogen from the hydrided magnesium based materials. It is believed that the dehydriding temperature is largely controlled by the thermodynamic configuration of magnesium hydride. Doping Mg-Ni nano/amorphous composite materials with lanthanum reduces the hydriding and dehydriding temperature. Although the stability of MgH2 can not be easily reduced by ball milling alone, the results suggest the thermodynamic properties of Mg-Ni nano/amorphous composite materials can be alternated by additives such as La or other effective elements. Further investigation toward understanding the mechanism of additives will be rewarded.

• Research Organization: Savannah River Site (US)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: AC09-96SR18500
• OSTI ID: 823470
• Report Number(s): WSRC-TR-2003-00239
• Journal Information: Journal of Alloys and Compounds, Journal Name: Journal of Alloys and Compounds; ISSN 0925-8388; ISSN JALCEU
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
36 MATERIALS SCIENCE
COMPOSITE MATERIALS
CRYSTAL STRUCTURE
ELECTRON MICROSCOPES
GRAIN SIZE
HYDROGEN
HYDROGEN STORAGE
KINETICS
LANTHANUM
MAGNESIUM
MAGNESIUM HYDRIDES
MORPHOLOGY
THERMODYNAMIC PROPERTIES
X-RAY DIFFRACTION