镁二次电池正极材料纳米Fe_3S_4的电化学性能

Electrochemical Properties of Nanostructured Greigite(Fe_3S_4)as a Cathode Material in Rechargeable Magnesium Battery

首次将尖晶石相的纳米Fe3S4材料用作镁二次电池的正极材料。采用水热法一步合成了具有纳米结构的Fe3S4材料,并采用XRD、SEM测试手段对产物的物相、形貌进行了表征。实验结果表明,在160℃能够合成纯相的Fe3S4材料,该材料具有银耳状纳米结构。电化学测试结果显示,水热法合成的纳米Fe3S4材料能够在镁二次电池体系中进行有效的可逆充放电,放电平台电压为0.9 V,首次放电容量高达267 m Ah·g-1,50次循环后衰减至110 m Ah·g-1。电化学交流阻抗测试结果表明镁离子能够在Fe3S4晶格中扩散。

Nanostructured greigite （Fe3S4） prepared by hydrothermal method was firstly used as a cathode material for rechargeable magnesium battery. The as-synthesized samples were characterized by X-ray diffraction （XRD） and scanning electron microscope （SEM）. Cyclic vohammetry and galvanostatic charge-discharge cycling tests showed that the obtained Fe3S4 could be reversibly cycled in rechargeable magnesium battery. The discharge voltage plateau located at 0.9 V. The nanostructured Fe3S4 electrode exhibited a high capacity of 267 mAh·g-1 during the first discharge Electrochemical impedance process, then the capacity gradually dropped to 110 mAh ·g-1 after 50 cycles. spectroscopy tests showed that Mg2＋ can diffuse in the lattice of Fe3S4.