Electrochemical and electrocatalytic behaviour of iron-base amorphous alloys in 1 M KOH at 25°C

The electrochemical and the electrocatalytic properties of Fe60Co20Si10B10 (Vitrovac 7600, G14), Fe40Ni40P14B6 (AC), Fe681 4Ni101 2Cr51 4Zr8B12 (BCC) and of Fe60Ni10Cr10Zr8B12 (BDI) iron base amorphous alloys in deaerated 1 M KOH aqueous solution and at 25°C was investigated. Poor electrocatalytic activity was exhibited by the amorphous alloys in the as-quenched state, while enhanced electrocatalytic activity was observed after anodic oxidation in situ at constant current density. The more active the amorphous alloy is in the alkaline solution, the better is its catalytic activity. The catalytic activity generally increases by increasing the oxidation current. This result has been attributed to an increase in the active surface of the catalyst after the anodic treatment rather than to an enhancement of the electronic properties of the surface. The G14 alloy exhibited the best catalytic properties among the alloys investigated. After an anodic treatment with a charging current of 0.5 mA cm-2 for 2 min, this alloy shows catalytic activity comparable to that of pure polycrystalline Pt in the same environment. © 1993.