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.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
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)
