球磨处理对LiAlH_4放氢动力学的影响  

Ball Mill Effect on the Dehydrogenation Kinetics of LiAlH_4

作　　者：孙泰[1] 黄存可[1] 董汉武[1] 王辉[1] 朱敏[1] 

机构地区：[1]华南理工大学机械工程学院,广州510640

出　　处：《西安交通大学学报》2008年第2期256-260,共5页Journal of Xi'an Jiaotong University

基　　金：教育部高等学校博士学科点专项科研基金资助项目(20040561001);广东省自然科学基金资助项目(04300126)

摘　　要：采用高能球磨对配位氢化物LiAlH4进行纳米化,通过X射线衍射分析,压力、组分等温测试等手段,研究了球磨时间、球料比等球磨参量对LiAlH4的微观结构和等温放氢性能的影响,并在此基础上揭示了球磨对LiAlH4的储氢性能和机制的影响.实验结果表明:LiAlH4分解为Li3AlH6和Al的放氢阶段与材料的晶粒尺寸有着密切的关系,较小的晶粒尺寸能有效地改善样品的储氢动力学性能;球磨能使Li3AlH6分解为LiH和Al的放氢阶段的起始温度显著降低;在适当的球磨参数下,LiAlH4的放氢有可能按不同于目前普遍认同的放氢模式进行.The influence of ball milling parameters such as milling time, ball to powder ratio on the micro structure and dehydrogenation kinetics of complex hydride has been studied by X-ray diffraction and pressure-composition isotherms. Results show that the dehydrogenation kinetic of decomposition from LiAlH4 to Li3AlH6 and Al has a close relationship with the crystalline size of raw-material. Reducing crystalline size can remarkably improve the hydrogen storage properties of LiAlH4. Ball milling can significantly decrease the decomposition temperature of Li3AlH6. However, the decomposition of LiAlH4 may proceed via a mode that differs from the traditional view.

关 键 词：储氢 配位氢化物 LiAlH4 等温放氢 

分 类 号：TG139.7[一般工业技术—材料科学与工程]