New response in electrochemical impedance spectroscopy due to the presence of molybdenum on AB5-type alloys

The replacement of manganese by molybdenum, in a 2% w/w concentration level (AB5M1), has a positive effect for applications as energy storage material. In this sense, this alloy exhibits the lowest value of charge transfer resistance obtained from the analysis of impedance spectra. Moreover, changes in the (i0. aa) parameter, that is, the exchange current density and active area, respectively display a maximum value. The larger grade of fracture observed in AB5M1 can be due to the higher material's fragility as a consequence of molybdenum incorporation. XRD analysis on the three alloys confirms this hypothesis as shown in the paper.