In this work,the effects of external field treatment on electrochemical behaviors and discharge performance of as-cast Mg-8%Al-0.5%Zn(wt%)anodes for Mg-air batteries are systematically investigated in3.5 wt%Na Cl solu...In this work,the effects of external field treatment on electrochemical behaviors and discharge performance of as-cast Mg-8%Al-0.5%Zn(wt%)anodes for Mg-air batteries are systematically investigated in3.5 wt%Na Cl solution.The external field treatment particularly the variable-frequency ultrasonic field can dramatically refine theα-Mg grains andμphases.The grain size decreases from 1594.8±43μm(untreated billet)to 140.6±15μm after variable-frequency ultrasonic field treatment.The values of open circuit potential,electrochemical activity and corrosion resistance of Mg-8%Al-0.5%Zn anode are improved with external field treatment,which should be attributed to refined grains and dispersiveαphase.The external field treatment especially the variable-frequency ultrasonic field improves stability and the value of cell voltage,and enhances the discharge performance of the Mg-8%Al-0.5%Zn anode.The variable-frequency ultrasonic field treated anode has the best discharge capacity and anodic efficiency at current density of 45 m A cm-2,with the values of 1417 m A h g-1 and 63.3%,respectively.The ultrasonic field vibration changes the dissolution behavior ofα-Mg matrix during the discharge process,showing the oriented surface morphologies.展开更多
基金financially supported by the National Key Research and Development Program of China(No.2016YFB0301104)the National Natural Science Foundation of China(No.51974082)the Programme of Introducing Talents of Discipline Innovation to Universities 2.0(the 111 Project of China 2.0,No.BP0719037).
文摘In this work,the effects of external field treatment on electrochemical behaviors and discharge performance of as-cast Mg-8%Al-0.5%Zn(wt%)anodes for Mg-air batteries are systematically investigated in3.5 wt%Na Cl solution.The external field treatment particularly the variable-frequency ultrasonic field can dramatically refine theα-Mg grains andμphases.The grain size decreases from 1594.8±43μm(untreated billet)to 140.6±15μm after variable-frequency ultrasonic field treatment.The values of open circuit potential,electrochemical activity and corrosion resistance of Mg-8%Al-0.5%Zn anode are improved with external field treatment,which should be attributed to refined grains and dispersiveαphase.The external field treatment especially the variable-frequency ultrasonic field improves stability and the value of cell voltage,and enhances the discharge performance of the Mg-8%Al-0.5%Zn anode.The variable-frequency ultrasonic field treated anode has the best discharge capacity and anodic efficiency at current density of 45 m A cm-2,with the values of 1417 m A h g-1 and 63.3%,respectively.The ultrasonic field vibration changes the dissolution behavior ofα-Mg matrix during the discharge process,showing the oriented surface morphologies.
