【摘要】 在氩气气氛下,采用机械球磨法制备AlCl3掺杂的4MgH2-Li3AlH6储氢材料,研究AlCl3对4MgH2-Li3AlH6脱氢性能的影响。借助热重(TG)法研究了4MgH2-Li3AlH6-AlCl3体系的放氢性能,并运用X射线衍射(XRD)分析和差示扫描量热(DSC)法对其反应机理进行了探索。实验结果表明,加入AlCl3可有效增加4MgH2-Li3AlH6体系的反应活性,促进二者分解放氢,并降低该体系的放氢温度,增大总脱氢量。当AlCl3的掺杂量为4%(摩尔分数)、磨球24颗、球磨时间2.0h和转速541r/min时,4MgH2-Li3AlH6-AlCl3体系起始放氢温度降至130℃,比4MgH2-Li3AlH6体系降低了43℃;且400℃时总脱氢量从5.5%(质量分数)增加到6.3%(质量分数)。同时,机理研究表明:在球磨过程中部分Li3AlH6和AlCl3发生反应,产生了活性Al,进而改善了体系的放氢性能。更多还原

【Abstract】 The hydrogen storage material of AlCl3 doped 4MgH2-Li3 AlH6 was successfully prepared by mechanical milling under an argon atmosphere.The effect of AlCl3 on the dehydrogenation of 4MgH2-Li3 AlH6 has been studied.The dehydrogenation performances of 4MgH2-Li3 AlH6-AlCl3 system were investigated by TG.The reaction mechanism was analyzed by XRD and DSC.The results show that AlCl3 as additive effectively increased the reaction activity of 4MgH2-Li3 AlH6,reduced the system dehydrogenation temperature and enhanced the dehydrogenate capacity.When 4mol% AlCl3 was doped into 4MgH2-Li3 AlH6,initial dehydrogenation temperature of this system was about 130℃ which was lower 43℃than 4MgH2-Li3 AlH6 ′s,and the total amount of dehydrogenation increased from 5.5wt% to 6.3wt%(up to 400 ℃).Meantime,the study on the mechanism of dehydrogenation for 4MgH2-Li3 AlH6-AlCl3 system shows that a part of Li3 AlH6 reacted with AlCl3 during ball-milled and activity Al was produced in situ.The activity Al helped to improve dehydrogenation performances of the system.更多还原