Research of Gerischer model in transferring electrons between energy states of CdS thin film and ferro-ferric redox system

A. Heidaripour, N. Ajami and S. Miandari

Physical Sciences Research International
Published: December 18 2015
Volume 3, Issue 4
Pages 59-64

Abstract

In this study, we describe interfacial electron transfer by semi classical theory described by Marcus and then developed by Gerischer, in which heterogeneous electron transfer is used for semiconductor/electrolyte interface. In this research, CdS thin film was electrodeposited on the indium tin oxide (ITO) and selected as an electrode for experiments. The kinetic constant rate and reorientation energy were measured in the solution with different concentrations of redox system: Fe³⁺/Fe²⁺. Increase of Fe³⁺ resulted in the increase of cathodic current. This increase is concern with the vicinity of redox potential to the valence band (VB) edge of CdS. The I-V curve and electrochemical impedance spectroscopy admitted reduction of Fe⁺³ on the VB of CdS.

Keywords: Fe³⁺/Fe²⁺ redox, cadmium sulfide, Gerischer model, indium tin oxide.

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