Electrochemical and Elctrocatalytic Behaviour of Iron-Base Amorphous Alloys in 1M KOH at 25 deg C

The electrochemical and the electrocatalytic properties of Fe sub 60 Co sub 20 Si sub 10 B sub 10 (Vitrovac 7600, G14), Fe sub 40 Ni sub 40 P sub 14 B sub 6 (AC), Fe sub 681/4 Ni sub 101/2 Cr sub 51 /4 Zr sub 8 B sub 12 (BCC) and of Fe sub 60 Ni sub 10 Cr sub 10 Zr sub 8 B sub 12 (BDI) iron-base amorphous alloys in deaerated 1M KOH aqueous solution and at 25 deg C were investigated. Poor electrocatalytic activity was exhibited by the amorphous alloys in the as-quenched state, while enhanced electrocatlytic 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 0.5mA cm exp --2 for 2 min, this alloy shows catalytic activity comparable to that of pure polycrystalline platinum in the same environment.