کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1278328 | 1497546 | 2012 | 6 صفحه PDF | دانلود رایگان |
We investigated the crystal structure and cyclic hydrogen absorption–desorption properties of Pr2MgNi9. The structural model is based on the PuNi3-type structure; the Mg atom is assumed to substitute for the Pr site in an MgZn2-type cell. The refined lattice parameters were determined from X-ray diffraction. A wide plateau region was observed in the P–C (pressure composition) isotherm at 298 K. The maximum hydrogen capacity reached 1.12 H/M (1.62 mass%) under a hydrogen pressure of 2.0 MPa. After 1000 hydrogen absorption–desorption cycles, the hydrogen capacity was superior to that of LaNi5 (82%). Anisotropic lattice strain occurred in the hydriding process. The anisotropic peak-broadening vector was determined to be <001>. The calculated anisotropic lattice strains of the initial cycle and after 1000 cycles were far smaller than those of LaNi5.
► The substituted Mg atom in the Pr2MgNi9 was located only at 6c site in the MgZn2-type cell.
► The maximum hydrogen capacity of the initial cycle of Pr2MgNi9 reached 1.12 H/M at 298 K.
► After 1000 cycles, the hydrogen capacity was kept at 85% of that of the initial cycle.
Journal: International Journal of Hydrogen Energy - Volume 37, Issue 23, December 2012, Pages 18095–18100