Voltammetric Study of Interfacial Electron Transfer between Bis(cyclopentadienyl)iron in Organic Solvents and Hexacyanoferrate in Water

Abstract

The electron-transfer reaction between bis(cyclopentadienyl)iron(II) ([Fe^II(C₅H₅)₂]) in nitrobenzene and a hexacyanoferrate redox couple ([Fe^II/III(CN)₆]^-4/3-) in water at the nitrobenzene | water interface was studied using normal pulse voltammetry. The voltammetric results indicate that the electron-transfer reaction takes place by way of a so-called ion-transfer (IT) mechanism, of which the forward and backward rate constants of the homogeneous electron-transfer reaction between [Fe^II/III(C₅H₅)₂]^0/+ and [Fe^II/III(CN)₆]^4-/3- in the water phase have been determined. The electron-transfer reaction between [Fe^II(C₅H₅)₂] in 1,2-dichloroethane and [Fe^II/III(CN)₆]^4-/3- in water at the 1,2-dichloroethane | water interface was shown to also take place by the IT-mechanism.