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The Potential of Zero Charge of Platinum and Its pH Dependence
by E. Gileadi, S. D. Argade, and J. O?V. Bockris Electrochemistry Laboratory, John Harrison Laboratory of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (Received December $1, 1965)
The potential of zero charge, V,,,, on platinum has been measured by various These results and the methods applied to obtain them have recently been discu~sed.’~~ Kheifetz and IirasikovgJowere the first to demonstrate that Vpzcon Pt (and a number of other transition metals) depended upon pH. They also observed that V,,, varied with the pretreatment of the electrode and, in particular, with the amount of absorbed hydrogen. In general, the potential of zero charge decreased (became more cathodic) with increasing pH. The relationship between Vpzoand pH was nonlinear and tended to level off at higher pH values. Prolonged cathodic treatment caused an increase in V,,, in alkaline media but had no effect a t pH
