The dealloying process of Pt-Co-Ni alloy(ca.2/l/l gross atomic ratio)supported on CB were investigated at the different of temperature and potential in h3po4. Even at the corrosion condition of 200°C,0.7 V for 48li, the Co and Ni component decreased appreciably. Fine particles of PlfCo'Ni] seemed to be dissolved predominantly leaving large-sized one (>100A) undissolved. Pti[Ni* Co] phase was found to be relatively stable. The Pt in the alloy was dissolved and deposited again as large-sized pure Pt particles during the corrosion process.

These electrocatalysts of various degradation levels are currently subjected to electrochemical measurements in order to examine effects of the degradation of electrocatalysts on the cell performances (see abstract by Nishizaki et al in our group).

0 0

Post a comment