Cyclic Voltammetry of the Electron Transfer Reaction between Bis(cyclopentadienyl)iron in 1,2-Dichloroethane and Hexacyanoferrate in Water

The electron transfer (ET) reaction between bis(cyclopentadienyl)iron(II) ([Fe1 II(C5H5)2]) in 1,2-dichloroethane (1,2-DCE) and hexacyanoferrate redox couple ([FeII/III(CN)6]4-/3-) in water (W) at the interface has been studied by using cyclic voltammetry. The voltammetric results can be explained well by a theoretical equation for the so-called IT-mechanism, in which a homogeneous ET reaction between [Fe(C5H5)2] (partially distributed from 1,2-DCE) and [Fe(CN)6]3- takes place in the W phase and the resultant [Fe(C5H5)2]+ ion is responsible for current passage across the interface. The forward rate constant of the homogeneous ET reaction, [Fe(C5H5)2] + [Fe(CN)6]3- = [Fe(C5H5)2]+ + [Fe(CN)6]4- in W phase, kfT, was determined to be (2.9 ± 2.2)x 1010 M-1 s-1, which was in good agreement with k(T = (3.2 ± 2.0)x 1010 M-1 s-1, which had been determined by using normal-pulse voltammetry.