Effective Laser Luminescence of Nanocomposites Eu(TTA)2(Ph3PO)2NO3-Polyvinylpyrrolidone

Abstract

Thin films (1-10 μm thickness) of nanocomposites (NC) based on organic coordinated compound (OCC) Eu(TTA)2(Ph3PO)2NO3 (where TTA is thenoyltrifluoroacetonate (C8H5F3O2S), Ph3PO - triphenylphosphine (C6H5PO) and polymer – polyvinylpyrrolidone ((C6H9NO)n) (PVP)) were obtained by chemical methods and with different molar ratios into organic polymer matrix. NC have been characterized by measurements of optical transmission, excitation spectra of photoluminescence (PL) and photoluminescence of NC at different concentrations of Eu(TTA)2(Ph3PO)2NO3 in NC. In the optical transmission of NC, the characteristic parameters of NC such as threshold absorbance, dependence on the concentration of the organic coordinated compound in NC, etc., have been determined The displacement of threshold absorption to infrared is observed with increasing of the concentration of the coordination material in NC. The excitation spectrum of photoluminescence of NC led the range from 200 to 400 nm energy at which takes place the photoluminescence in NC. The PL of nanocomposites was detected as specific for internal transitions 4f → 4f of the Eu3+ ion 5D0 → 7Fi (i = 0,1,2,3 and 4) centred at 537, 578, 615, 632,649, 690 and 705 nm, respectively at T=300 K. The dominant PL is in the position to 615 nm and the halfwidth is less than 10 nm and it is attributed to the transition 5D0 → 7F2. The comparison of PL of NC with organic coordinated compounds at equal ultraviolet exciting show the increasing of the external efficiency of NC luminescence. In nanocomposites, the effect of energy transfer from polymer matrix to coordinated molecule with subsequent transfer of them to Eu+3 ion have been identified. It was proposed some applications of given nanocomposites in optoelectronics and medicine.