非晶纳米晶Mg-Ni型复合储氢合金微观结构及电化学性能  

Microstructure and electrochemical properties of Mg-Ni-type hydrogen storage alloy with nanocrystalline/amorphous structure

作　　者：胡锋[1] 蔡颖[1] 李永治[2] 赵鑫 许剑轶[1] 张羊换[1] HU Feng1, CAI Ying1, LI Yong-zhi2, ZHAO Xin1, XU Jian-yi1, , ZHANG Yang-huan1(1. Materials and Metallurgy- School , Inner Mongolia University of Science and Technology, Baotou 014000, China;2 and Physical Sciences School, Inner Mongolia University of Science and Technology-, Baotou 014000, China)

机构地区：[1]内蒙古科技大学材料与冶金学院,内蒙古包头014010 [2]内蒙古科技大学数理学院,内蒙古包头014010

出　　处：《内蒙古科技大学学报》2018年第2期113-118,共6页Journal of Inner Mongolia University of Science and Technology

基　　金：国家自然科学基金资助项目(51371094);内蒙古自然科学基金资助项目(2014MS0529);内蒙古科技大学创新基金资助项目(2014QDL015)

摘　　要：为了改善Mg-Ni型储氢合金的电化学性能,采用机械球磨法制备Mg/Ni/TiF_3复合储氢合金.通过X射线衍射(XRD)、扫描电子显微镜(SEM)、恒电流放电容量测试、高倍率放电能力(HRD)测试,电化学交流阻抗谱(EIS)、恒电位阶跃(时阳极电流-时间响应曲线)以及动电位极化研究了合金材料的微观结构与电化学性能.结果表明:球磨复合储氢合金由非晶纳米晶Mg2Ni与Ni主相组成,同时包括少量的第三相Mg Ni2与Ti Ni.添加质量分数为5%TiF_3的Mg50Ni50/TiF_3复合材料拥有最好的电化学放电容量,这与其具有非晶纳米晶结构及吸氢后形成Mg2Ni H4相有关.X射线衍射分析表明:球磨质量分数为5%TiF_3/Mg50Ni50复合材料非晶化程度最强,这在一定程度上改善了其电化学循环稳定性与动力学性能.The Mg/Ni/TiF_3 composite hydrogen storage alloys were synthesized by ball mechanical milling method to improve the electrochemical properties of Mg-Ni type hydrogen storage alloys. Microstructure and electrochemical performance of ball milled alloys were characterized by X-Ray diffraction（XRD）,scanning electron microscopy（SEM）,test of discharge capacity,high rate discharge ability（HRD）,electrochemical AC impedance spectrums（EIS）,potential-step method（response curve of current versus time） and potentiodynamic polarization. The results showed that the ball-milled composite hydrogen storage alloys had a multiphase structure consisted of two main phases Mg2 Ni and Ni as well as a small amount of third phase Mg Ni2 and Ti Ni. The ball milled Mg50 Ni50/TiF_3 composite with 5% TiF_3（in mass fraction） possessed optimal electrochemical discharge capacity,which was relevant to amorphous/nanocrystalline structure and hydride Mg2 Ni H4 phase after absorbing hydrogen. X-Ray diffraction analysis indicated that the ball-milled Mg50 Ni50/TiF_3（5% in mass fraction） composite exhibits the strongest amorphization degree,which ameliorated its electro-chemical cycle stability and kinetics properties to some degree.

关 键 词：机械球磨法 非晶纳米晶 循环稳定性 电化学动力学性能 放电容量 

分 类 号：TG139[一般工业技术—材料科学与工程]