Förster resonant energy transfer from alumina luminescence centers to dye molecules adsorbed in anodic alumina thin films used as coatings and in sensors

Förster resonant energy transfer from anodic alumina luminescence centers to rhodamine 6G dye molecules adsorbed in the alumina thin film pores and on the film surface has been revealed and investigated. The anodization process of thin aluminum films obtained by physical vapor deposition was monitored by means of in situ reflection spectroscopy. Without dye, alumina luminescence intensity increases with an increase of the electrolyte temperature during anodization. Adsorption of organic dyes on the anodized surface and in its pores leads to quenching of the luminescent centers emission and to an increase in the luminescence of the dye. Simultaneous decrease of the luminescence decay time points at Förster resonant energy transfer as a mechanism of dye luminescence enhancement. The results of the work can be used to create new sensors with a luminescent response for in-vitro disease diagnostics and for fabrication of novel optical coatings.