Charge-transfer processes, scanning SECM

A few years ago Bard and his group developed the technique called scanning electrochemical microscopy (SECM) which makes possible a spatial analysi,s of charge transfer processes [9]. In this method an additional tip electrode of a diameter of about 2 pm is used as well as the three other electrodes (semiconductor, counter and reference electrode). Assuming that a redox system is reduced at the semiconductor, then the reduced species can be re-oxidized at the tip electrode, the latter being polarized positively with respect to the redox potential. The corresponding tip current / [ is proportional to the local concentration of the product formed at the semiconductor surface and therefore also to the corresponding local semiconductor current, provided... 

C Wei, AJ Bard, MV Mirkin. Scanning electrochemical microscopy. 31. Application of SECM to the study of charge-transfer processes at the liquid-liquid interface. J Phys Chem 99 16033-16042, 1995. 

Wei, C., Bard, A. J., Mirkin, M. V. Scanning electrochemical microscopy. 31. Application of SECM to the study of charge transfer processes at the liquid/liquid interface. J. Phys. Chem. 1995, 99, 16033. Tsionsky, M., Bard, A. J., Mirkin, M. V. Scanning electrochemical microscopy. 34. Potential dependence of the electron-transfer rate and film formation at the liquid/liquid interface. J. Phys. Chem. 1996, 100, 17881. 

C. Wei, A. J. Bard, and M. V. Mirkin,/. Phys. Chem., 99, 16033 (1995). Scanning Electrochemical Microscopy. 31. Application of SECM to the Study of Charge-Transfer Processes at the Liquid-Liquid Interface. 

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