Luminescence and energy transfer of organic chromophores bound to inorganic nano-lamellar frameworks.
Fluorescein, an organic chromophore with high fluorescence quantum yield, was bound to a cetyltrimethylammonium zirconium phosphate nano-lamellar framework and its luminescence properties and energy transfer from fluorescein to porphyrins were characterized. Upon the incorporation of fluorescein chromophore within the layered materials, not only was the interlayer distance of the framework adjusted from 39.6 to 24.7 angstroms, but also the luminescence properties of fluorescein were dramatically changed. The excitation maximum was red-shifted from 488 to 500 nm, and the emission peak was red-shifted from 510 to 525 nm. These results implied the formation of chromophore/framework hybrid assemblies. After fluorescein and tetra(p-methoxphenyl)porphine chromophores bound to the framework together, obvious energy transfer was observed, resulting in more effective fluorescence efficiency for the porphyrins. Without the framework, such energy transfer was absent in the same chromophore concentrations in aqueous solutions. Due to the unique microenvironments provided by the inorganic lamellar framework, the electronic interactions of the chromophores were tuned. Therefore, their emission properties were changed, and the energy transfer processes were promoted.
Shi
Shikao
S
College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang 050016, China.
Zhou
Ji
J
Han
Shitian
S
Ye
Jianping
J