Effect of Ga on microstructure and electrochemical performance of Al−0.4Mg−0.05Sn−0.03Hg alloy as anode for Al−air batteries  

合金元素Ga对铝空气电池阳极Al−0.4Mg−0.05Sn−0.03Hg合金显微组织和电化学性能的影响

作　　者：Ze-hang ZHUANG Yan FENG Chao-qun PENG Liu-zhong YANG Meng WANG 庄泽航;冯艳;彭超群;杨柳忠;王檬(中南大学材料科学与工程学院,长沙410083;中南大学电子封装与先进功能材料重点实验室,长沙410083)

机构地区：[1]School of Materials Science and Engineering,Central South University,Changsha 410083,China [2]Key Laboratory of Electronic Packaging and Advanced Functional Materials,Central South University,Changsha 410083,China

出　　处：《Transactions of Nonferrous Metals Society of China》2021年第9期2558-2569,共12页中国有色金属学报（英文版）

基　　金：This work is supported by the Equipment Pre-research Laboratory Foundation in Central South University,China(No.6142912200104).

摘　　要：The effects of 0.01 wt.%Ga on microstructure and electrochemical performance of Al−0.4Mg−0.05Sn−0.03Hg anodes in NaOH solutions were investigated.Potentiodynamic polarization,electrochemical impedance spectroscopy,and galvanostatic discharge tests were used to assess the electrochemical performance of the Al−Mg−Sn−Hg−Ga anodes.The results show that the addition of 0.01 wt.%Ga in Al−0.4Mg−0.05Sn−0.03Hg anode enhances its corrosion resistance and discharge activity.It is benefited from the refined second phases and homogenous microstructure of Al−Mg−Sn−Hg−Ga anode,which restrains the local crystallographic corrosion and chunk effect.Compared with Al−Mg−Sn−Hg anode,the corrosion current density and the mass loss rate of Al−Mg−Sn−Hg−Ga anode decrease by 57%and 93%,respectively.When discharging at the current density of 20 mA/cm^(2),the discharge voltage,current efficiency and specific capacity of the single Al−air battery with Al−0.4Mg−0.05Sn−0.03Hg−0.01Ga anode are 1.46 V,33.1%,and 1019.2 A·h·kg^(−1),respectively.The activation mechanism of Ga on Al−Mg−Sn−Hg−Ga anode materials was also discussed.采用动电位极化法、电化学阻抗谱法和恒电流放电法研究添加0.01%Ga(质量分数)对Al−0.4Mg−0.05Sn−0.03Hg阳极的显微组织和在NaOH溶液中的电化学性能的影响。结果表明,Ga的添加增强Al−Mg−Sn−Hg阳极的耐蚀性和放电活性,这得益于Ga的加入能细化Al−Mg−Sn−Hg阳极的第二相,使显微组织更加均匀,从而抑制局部腐蚀和块效应。与Al−Mg−Sn−Hg阳极相比,Al−Mg−Sn−Hg−Ga阳极的腐蚀电流密度降低57%,质量损失率降低93%。在20 mA/cm^(2)放电电流流密度下,以Al−0.4Mg−0.05Sn−0.03Hg−0.01Ga为阳极的单个铝空气电池的放电电压、电流效率和放电容量分别为1.46 V,33.1%和1019.2 A·h·kg^(−1)。此外,还讨论Ga在Al−Mg−Sn−Hg−Ga阳极材料上的活化机理。

关 键 词：aluminum alloy ELECTROCHEMISTRY corrosion Al−air battery 

分 类 号：TM911.41[电气工程—电力电子与电力传动] TG146.21[一般工业技术—材料科学与工程]