S. Rodman et Mt. Spitler, Determination of rate constants for dark current reduction at semiconductor electrodes using ZnO single-crystal microelectrodes, J PHYS CH B, 104(40), 2000, pp. 9438-9443
A method based on microelectrodes of ZnO single crystals was employed to de
termine the effective reaction velocity for dark reduction of ferrocenium a
ccepters by electrons from the semiconductor conduction band. Measurement t
echniques were explored and theoretical models for steady-state voltammetry
at semiconductor electrodes developed. The microelectrode method as presen
ted here represents an unambiguous experimental method for ascertaining ide
al interfacial behavior even at high current flows found near the flatband
potential. These results are compared with reaction velocities derived from
extrapolation methods at millimeter-sized ZnO electrodes. It is seen that
the extrapolation method is insensitive to nonideal behavior in the reducti
on reaction whereas the microelectrode method is not.