Of La-ni-al Hydrogen Storage Material Micro-structural Properties Of Neutron Diffraction Study

Using neutron scattering technique a series of LaNi_5-xAl_x (x=0, 0.1, 0.25, 0.3, 0.45, 0.5, 0.75) alloys and their deuterides were studied, and then the information about the corresponding crystal structure, the components of the phases and the occupying positions were obtained. Meanwhile, the relation between the structure and properties of the samples were discussed as well.A series of experimental data of LaNi_5-xAl_x alloys were refined by means of program FullProf. Their space groups were found to be P6/mmm. The alloys' lattice parameters, cell volumes and atomic positions were obtained. It was discovered that Al atoms just substituted a part of Ni atoms which were at 3g position. Furthermore it was also learned that the variety of cell volume was almost proportional to the content of Al atoms in the alloys.The refined results of LaNi_5-xAl_x diffraction data showed that the deuteride's space groups were still P6/mmm. The varieties of phase components, lattice parameters and cell volumes were analyzed after charging deuterium, afterwards the atomic positions and distribution of deuterium atoms in the cell were obtained. Refering to the behaviors of hydrogen absorption and desorption of LaNi_5-xAl_x alloys in the literatures, the relation between the content of Al and the performance in storing hydrogen was discussed.