It is shown that it is possible to carry out electrochemical reactions in poorly conducting and nonconducting media by means of bipolar electrolyses with dispersions. Polarization equations are predicted for highly simplified models based on the concept of the mixture potential, the surface reactions being assumed to be rate determining. Results for hydrogen evolution/oxidation and oxygen evolution/reduction show that the interpretation of polarization curves at high field strengths will have to take into account the effects of diffusion. The results also show that it should be possible to investigate, monitor, and modify heterogeneous catalyses of reactions in the liquid phase by means of the faradaic currents induced by the electric fields.

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The bipolar electrolysis of suspensions of spherical ultramicroelectrodes is discussed. It is shown that the reactions at the surface will be rate controlling over a wide range of conditions in view of the high rates of mass transfer to the electrodes. The effects of diffusion can be taken into account in a straightforward manner in view of the absence of discontinuities in the spherical coordinate system. Bipolar electrolyses on ultramicroelectrodes can also be used for kinetic measurements and synthesis in solutions containing no deliberately added support electrolyte. Estimates are made of the effects of the coupling of diffusion and migration; exact predictions of the asymmetric polarization of the particles under these conditions will require numerical analysis.