Promotion of Forster Resonance Energy Transfer in a Saponite Clay Containing Luminescent Polyhedral Oligomeric Silsesquioxane and Rhodamine Dye

A new hybrid photostable saponite clay with embedded donor-acceptor dyes was prepared and characterized in this work. The saponite is intercalated with a luminescent polyhedral oligomeric silsesquioxane, which transfers the photoexcitation energy directly to an acceptor dye (rhodamineB). The obtained composite material was characterized by means of XRD, TEM microscopy, and UV/Vis and photoluminescence spectroscopy. A physicochemical study showed that the system behaved as an efficient Forster resonance energy transfer pair, owing to the very good spectral overlap of donor emission ((em)=510-540nm) and acceptor absorption in the =530-570nm range. The hybrid material represents the first example of a photonic antenna based on a synthetic saponite clay and can be considered a step forward in the search for new, efficient, and stable materials suitable for light-harvesting applications.