Droplet-size dependence of the electron transfer rate across the single-microdroplet/water interface

Electron transfer between ferrocene in a single oil droplet and hexacyanoferrate(III) in the surrounding water phase was studied by laser trapping, spectroscopic, and electrochemical techniques. We determined the rate of interfacial electron transfer for an individual droplet and found for the first time that the rate increased with a decreased in the droplet diameter. This particular micrometer size dependence was discussed on the basis of kinetic analysis of the electron transfer rate.