Authors: Xiulin Fan Xuezhang Xiao Lixin Chen Shouquan Li Hongwei Ge Qidong Wang
Publish Date: 2011/01/06
Volume: 46, Issue: 10, Pages: 3314-3318
Abstract
Nanocrystalline Na2LiAlH6 was directly synthesized by mechanical milling 2NaH/LiH/Al mixture with TiF3 catalyst under hydrogen pressure of 30 MPa The synthesized Na2LiAlH6 exhibits a dehydriding capacity of 309 wt in the first cycle which is higher than that of Na3AlH6 Because of the complexity of mass transfer the rehydrogenation process of the dehydrided Na2LiAlH6 is more intricate than that of the dehydrided sodium alanate causing the formation of Na3AlH6 and the reduction of rehydriding capacity in the following cycles As temperature increases from 70 to 120 °C hydrogen absorption kinetics is extremely enhanced The dehydrided material can reabsorb 80 of the reversible hydrogen capacity within 5 min when the temperature is above 100 °C with an initial hydrogen pressure of 4 MPa The scanning electron microscopy and energy dispersive Xray spectroscopy show that the assynthesized Na2LiAlH6 along with the catalyst form a much homogeneous composite with a spherical particle size of 200 nm–2 μmThe authors wish to acknowledge the financial support of this research from the National Basic Research Program of China Grant No 2007CB209701 the National Natural Science Foundation of China Grant No 51001090 50871099 and 50631020 the Program for New Century Excellent Talents in University Grant No NCET070741 the University Doctoral Foundation of the Ministry of Education Grant No 20090101110050 and the China Postdoctoral Science Foundation Grant No 200902622
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