掺杂催化剂对NaAlH4吸放氢性能和微观结构的影响  

The effect of catalysts on the hydriding/dehydriding(H/D) properties and microstructures of NaAlH_4

作　　者：王国清[1] 赵栋梁[1] 张羊换[1] 郭世海[1] 王新林[1] 

机构地区：[1]钢铁研究总院功能材料研究所,北京100081

出　　处：《功能材料》2008年第2期231-233,237,共4页Journal of Functional Materials

基　　金：国家自然科学基金重点资助项目(50131040);内蒙古科技计划资助项目(20050205)

摘　　要：利用PCT测试仪和X射线衍射及场发射扫描电镜等测试手段对NaAl H4+2%(摩尔分数)M(M=Ni、LaCl3、Ce(SO4)2)的吸放氢性能和微观结构进行了研究。结果表明,催化剂的掺杂均可降低NaAl H4的放氢温度,催化剂的催化效果依次为:Ce(SO4)2>LaCl3>Ni。掺杂稀土化合物可改善NaAl H4的吸氢性能,使第一步吸氢反应:3NaH+Al+3/2H2→Na3Al H6完全发生,特别是Ce(SO4)2的掺杂,使样品发生了部分1/3Na3Al H6+2/3Al+H2→NaAl H4的第二步吸氢反应,吸氢量达到2.808%(质量分数)。掺杂Ce(SO4)2有利于NaAl H4在球磨过程中颗粒尺寸细化,颗粒的细化增强了NaAl H4的活性,导致其吸放氢性能提高。The hydriding/dehydriding（H/D） properties and microstructures of NaAlH4＋2mol% M（M=Ni,LaCl3,Ce（SO4）2） were investigated by PCT testing instrument,XRD and FESEM.The obtained results show that catalysts can decrease the dehydriding temperature of NaAlH4 and the catalytic activity of the catalysts is in the series Ce（SO4）2〉LaCl3〉Ni.Doping rare earth compounds can improve the hydriding property of NaAlH4,leading to the first hydriding reaction 3NaH＋Al＋3/2H2→Na3AlH6 completely occurred.Especially the doping of Ce（SO4）2 makes the second hydriding reaction 1/3Na3AlH6＋2/3Al＋H2→NaAlH4 taken place partially,and the absorbed hydrogen capacity could arrive at 2.808wt%.This is attributed to the particle refinement during ball milling doping with Ce（SO4）2 and activity of NaAlH4 enhanced by particle refinement.

关 键 词：NaAlH4 催化剂 吸放氢性能 微观结构 

分 类 号：TG139[一般工业技术—材料科学与工程]