Ni对Mg(NH_2)_2纳米空心球与LiH混合体系放氢性能的影响  

Hydrogen desorption properties of Ni nanoparticles doped Mg(NH_2)_2 hollow nanosphere mixed with LiH

作　　者：张旋洲[1,2] 杨均智[2] 宋萍[2] 田文怀[1] 李星国[2] 

机构地区：[1]北京科技大学材料物理与化学系,北京100083 [2]北京大学化学与分子工程学院,北京100871

出　　处：《功能材料》2011年第12期2137-2140,2145,共5页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(20971009;20821091;51071003);国家重点基础研究发展计划(973计划)资助项目(2009CB939902;2010CB631301)

摘　　要：将氨气等离子体法制备的50nm左右的Mg3N2纳米颗粒与氨气反应,成功合成出大小约为80nm,球壳厚度约为10nm的Mg(NH2)2纳米空心球。利用Mg(NH2)2纳米空心球制备的Mg(NH2)2+2LiH储氢体系,比普通Mg(NH2)2+2LiH具有更低的放氢温度,放氢活化能从149.1kJ/mol降低到了117.6kJ/mol。对该体系添加纳米级的Ni作为催化剂,放氢活化能进一步降低为108.0kJ/mol。反应后生成物颗粒大小取决于反应前Mg(NH2)2颗粒的大小。通过对放氢性能的比较,讨论了影响Mg(NH2)2+2LiH体系放氢性质的因素和决速步骤。Mg3N2 nanocubes with particle size about 50nm were synthesized by vaporized bulk magnesium with ammonia plasma metal reaction.Reacted the Mg3N2 nanocubes with NH3,Mg（NH2）2 hollow nanospheres with particle sizes of about 80nm and the shell thickness of about 10nm were successfully synthesized.Hydrogen desorption temperature of Mg（NH2）2＋2LiH system was lowered by use of Mg（NH2）2 hollow nanospheres,and the desorption activation energy was lowered from 149.1 to 117.6kJ/mol.Furthermore,the desorption activation energy was lowered to 108.0kJ/mol by doping with Ni nanoparticles.The particle size of resultant after dehydrogenation lied on the size of Mg（NH2）2.The factors on the hydrogen desorption kinetics of Mg（NH2）2＋2 LiH system were also discussed.

关 键 词：氨基化合物 储氢材料 催化 纳米空心球 

分 类 号：TK91[动力工程及工程热物理]