Electrochemical Properties of MgNi-ZrB Hydrogen Storage Alloys

摘要:

通过机械球磨法制备了一系列的MgNi、ZrB和MgNi-ZrB储氢合金。通过XRD、SEM、充放电性能、循环伏安、塔菲尔极化曲线、交流阻抗测试，研究了ZrB的添加对MgNi合金的储氢性能的影响。结果表面，ZrB的添加大大提高了MgNi合金的电化学性能。球磨15 h的MgNi-ZrB (100:5)复合物体现出最好的电化学性能，循环20周和50周时的放电容量分别为226和209 mAh·g-1，远远高于MgNi合金的放电容量。动态极化曲线和交流阻抗测试显示ZrB的添加极大的提高了MgNi合金的抗腐蚀性能和电化学动力学性能

Abstract:

A series of MgNi-ZrB composites were prepared from MgNi alloy and ZrB alloy by a mechanical alloying (MA) method. The influences of ZrB doping on the structures and the electrochemical properties of MgNi alloy were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), charge-discharge cycles, cyclic voltammetry (CV), Tafel polarization and electrochemical impedance spectroscopy (EIS). The results demonstrate that ZrB doping obviously improves the cycle life of MgNi alloy. The MgNi-ZrB (100:5) composite made from the doped powder ball milled for 15 h exhibits the best electrochemical performances. It shows high discharge capacities of 226 and 209 mAh·g-1 after 20 and 50 cycle, respectively, which are much higher than that of MgNi alloy. Potentiodynamic polarization and EIS tests show that ZrB doping improves the anticorrosion and the electrochemical kinetic properties of MgNi alloy significantly