BULK AND SURFACE-PROPERTIES OF CRYSTALLINE AND AMORPHOUS ZR-36(V0.33NI0.66)(64) ALLOY AS ACTIVE ELECTRODE MATERIAL

The electrochemical hydrogen absorption/desorption behavior of a cryst alline and an amorphous Zr-36(V0.33Ni0.67)(64) alloy sample was invest igated. Electrodes made of the crystalline sample show a much lower re sistance and consequently a higher discharge capacity compared to the electrodes made of the amorphous alloy. The XPS surface analysis did n ot explain the difference, we observed almost exactly the same depth p rofile on both samples. However the surface of the activated alloy com pared to the non-activated was drastically changed. The oxide layer on an amorphous alloy seems to grow in a much more compact and stable st ructure than the oxide layer on a crystalline sample. (C) 1998 Elsevie r Science S.A.