Preparation and hydrogen storage properties of an Li-Mg-N-H system

作     者：TIAN Chao YANG HuaBin 

作者机构：Institute of New Energy Material ChemistryNankai UniversityTianjin 300071China 

出 版 物：《Science China Chemistry》 (中国科学（化学英文版）)

年 卷 期：2009年第52卷第9期

页      面：1412-1416页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：Supported by the 863 Program of China (Grant No. 2007AA05Z149) the Natural Science Foundation of Tianjin, China (Grant No. 07JCZDJC02700) 

主　　题：Li-Mg-N-H system ball milling method hydrogen storage reversibility capacity decay 

摘      要：An Li-Mg-N-H system has been synthesized from Mg(NH2)2 and LiH in the ratio 3:8 by a ball-milling process and its dehydrogenation/rehydrogenation properties at around 190°C were investigated. XRD, FTIR and TG results showed that the system was composed of an LiH phase and an amorphous Mg(NH2)2 phase with a purity of 90%. A reversible hydrogen storage capacity of 4.7% was observed during the first cycle and more than 90% of the stored hydrogen was desorbed within 100 min for each cycle. However, only 4.2% and 2.9%, respectively, of hydrogen was observed during two subsequent dehydrogenation cycles. In situ GC results showed that no NH3 could be observed during the dehydrogenation process. On the basis of the SEM and XRD results, the loss in hydrogen storage capacity can be mainly attributed to agglomeration, oxidation and crystallization of the materials.