Platinum Metals Review - Volume 34, Issue 3, 1990

The catalytic activity and selectivity of platinum metals can be altered dramatically and reversibly by interfacing the metal with a solid electrolyte which supplies ions onto the catalyst surface under the influence of an external potential. The induced change in catalytic rate is orders of magnitude higher than the rate of ion supply. This new effect has revealed a surprisingly simple exponential relationship between catalytic activity and catalyst work function. The effect appears to apply to all heterogeneously catalysed reactions, but is particularly pronounced for platinum. This interfacing of electrochemistry and catalysis appears to offer some exciting theoretical and technological possibilities.

The first part of this paper reviewed the effects of sulphuric acid on stainless steels modified by platinum metals additions, much of the original work having been carried out by Russian researchers. Now corrosion in other media, and oxidation, are considered and a review of the limited data that are available on mechanical properties is presented. It is concluded that, in particular circumstances, improved material properties can be obtained by the addition of platinum group metals to iron-base alloys.