物理化学学报 >> 2009, Vol. 25 >> Issue (02): 237-241.doi: 10.3866/PKU.WHXB20090207

研究论文 上一篇    下一篇

机械球磨固相化学反应制备AlH3及其放氢性能

罗永春; 毛松科; 阎汝煦; 孔令斌; 康龙   

  1. 兰州理工大学材料科学及工程学院, 兰州 730050; 兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室, 兰州 730050
  • 收稿日期:2008-08-14 修回日期:2008-10-23 发布日期:2009-01-16
  • 通讯作者: 罗永春 E-mail:luoyc@lut.cn

Synthesis of AlH3 by a Ball-Milling Solid-Phase Chemical Reaction and Its Hydrogen Desorption Properties

LUO Yong-Chun; MAO Song-Ke; YAN Ru-Xu; KONG Ling-Bin; KANG Long   

  1. College of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou 730050, P. R. China; State Key Laboratory of Gansu Advanced Non-Ferrous Metal Materials, Lanzhou University of Technology, Lanzhou 730050, P. R. China
  • Received:2008-08-14 Revised:2008-10-23 Published:2009-01-16
  • Contact: LUO Yong-Chun E-mail:luoyc@lut.cn

摘要: 以LiAlH4和AlCl3为原料, 采用机械球磨固相化学反应方法制备了铝氢化合物, 通过X射线衍射(XRD)、热分析(TG-DSC)和质谱(MS)分析等方法对反应产物进行分析和表征, 研究了不同球磨时间(4、8、15和20 h)对LiAlH4+AlCl体系的固相反应转变规律﹑合成产物和放氢性能的影响. 研究结果表明, 随球磨时间的增加, 球磨固相反应按3LiAlH4+AlCl3→4AlH3+3LiCl方向进行, 形成了非晶态铝氢化合物AlH3, 球磨20 h时反应基本完全. 球磨产物的放氢动力学特性随球磨时间增加而改善, 其放氢起始温度均低于100 ℃, 最大放氢量达到2.6%-3.6%(H2)(w), 接近反应体系的理论储氢量4.85%(H2)(w). 球磨过程中反应产物形成LiCl·H2O以及少量AlH3发生分解是影响球磨产物最大放氢量的主要因素.

关键词: 金属氢化物, 机械球磨, AlH3, 热分析放氢性能

Abstract: The synthesis of AlH3with LiAlH4 and AlCl3was done by ball-milling solid phase chemical reaction under H2 atmosphere. The effects of different milling times (4-20 h) on the solid state chemical reaction and dehydrogenation properties of the milled mixture were investigated comprehensively using X-ray diffraction (XRD), thermal analysis (TG-DSC), mass spectroscopy (MS), scanning electron microscopy (SEM), and dehydrogenation measurements. The milled reaction was found to proceed as follows: 3LiAlH4+AlCl3→4AlH3+3LiCl. The reaction was almost complete after milling for 20 h and amorphous AlH3 was formed. With an increase in milling time dehydrogenation kinetics was improved resulting in hydrogen desorption at a temperature lower than 100 ℃. The maximum desorbed hydrogen capacities reached 2.6%-3.6% (w), which is close to the theoretical capacity of 4.85% (w) for the reaction. A decrease in the maximum desorbed hydrogen capacity can be attributed to the formation of LiCl·H2O and also to the decomposition of AlH3 during the milling process.

Key words: Metal hydride, Mechanically ball-milling, AlH3, Thermal analysis, Dehydrogenation property

MSC2000: 

  • O643