The distance dependence of charge transfer efficiency from a rhodamine dye to a TiO2-based semiconductor film in the near field of Ag nanoparticles

Abstract

The distance dependence of charge transfer efficiency from rhodamine dye to a TiO₂-based semiconductor film was studied, and the influence of plasmon core@shell nanoparticles (Ag@TiO₂) on this process is considered. The distance between the dye and the semiconductor was controlled using monolayers of polyampholyte (∼2 nm). The fluorescence intensity of the dye exhibits a strong dependence on the distance to semiconductor film, accompanied by changes in the lifetime of the electron-excited state of dye. In the presence of Ag@TiO₂ nanoparticles, the charge transfer was significantly enhanced that was confirmed by the growth of photocurrent of the solar cell (by 47 %).