组成对Li-Mg-N-H系统储氢性能的影响  

Effects of Composition on Hydrogen Storage Properties of Li-Mg-N-H System

作　　者：秦董礼 赵晓宇[1] 张轲[1] 鲁捷[1] 张洪波[1] 辛士刚[1] 

机构地区：[1]沈阳师范大学,辽宁沈阳110034

出　　处：《稀有金属材料与工程》2015年第2期355-359,共5页Rare Metal Materials and Engineering

基　　金：辽宁省教育厅科研一般项目(L2012394);沈阳师范大学主任基金(Sy2x1002)

摘　　要：研究了2种不同组成(2Li NH2-1.1Mg H2和Mg(NH2)2-2.2Li H)的Li-Mg-N-H储氢材料系统储氢性能,通过P-C-T曲线以及脱氢反应动力学的测定,发现这2种组成的样品脱氢产物均为Li2Mg(NH)2,其在200℃以上具有良好的可逆性,可逆储氢量可达4.6%(质量分数)以上;2种组成的系统不同仅在于前者多余Mg H2而后者多余Li H,其对系统脱氢反应的热力学性质如焓变、熵变以及自由能改变不大,但多余Mg H2的样品较多余Li H的样品,系统脱氢反应的动力学较快,具有较低的活化能。Hydrogen storage properties of two Li-Mg-N-H systems with different compositions, 2Li NH2-1.1Mg H2 system and Mg（NH2）2-2.2Li H system, were studied by a PCT pro2000 apparatus. The results of P-C-T curves and kinetics of dehydrogenated reaction at temperatures of 150~240 oC show that the dehydrogenated products of the two systems are Li2Mg（NH）2, and it has good reversibility for hydrogen absorption and desorption reaction, and their reversible hydrogen storage quantity can reach 4.6 wt% above 200 oC. The calculations by Van＇t Hoff equation based on P-C-T curves suggest that thermodynamics properties such as enthalpy, entropy, and free energy for the two systems have a small difference; however, kinetics data of dehydrogenated processes indicate that the 2Li NH2-1.1Mg H2 system has lower activation energy and quicker dehydrogenated reaction rate than the Mg（NH2）2-2.2Li H system.

关 键 词：Li-Mg-N-H系统 P-C-T曲线 脱氢反应动力学 储氢性能 

分 类 号：TB34[一般工业技术—材料科学与工程]