Modeling of trap assisted interfacial charge transfer in dye sensitized solar cells

Abstract

This paper presents a model for charge transport in dye sensitized solar cells based on the physics of electron capture, electron emission, oxidation, and reduction processes mediated by deep interfacial trap states at TiO2/dye/electrolyte interfaces. This model suggests that electron back injection from the conduction band of TiO2 to electrolyte is due to trapping of conduction band electrons by deep states followed by reduction processes at the interface. The simulated dark IV, illuminated IV, and quantum efficiency characteristics of dye sensitized solar cells based on this model are consistent with experimental results.