Photoluminescence properties of PVP/Eu(TTA) 2(Phen 3PO) 2NO 3 nanocomposites

Abstract

Thin films (1–10 μm thickness) of nanocomposites (NC) based on organic coordinated compound (OCC) Eu(TTA) 2 (Phen 3 PO) 2 NO 3 (where TTA is thenoyltrifluoroacetonate ( C 8 H 5 F 3 O 2 S), Phen – 1,10 -phenanthroline ( C 12 H 8 N 2 )) and polymer – polyvinylpyrrolidone ( (C 6 H 9 NO) n ) ( PVP)) were obtained by chemical methods. NC were characterized by measurements of optical transmission, and photoluminescence (PL) at different concentrations of Eu(TTA) 2 (Phen 3 PO) 2 NO 3 in NC. Using the optical transmission spectra, the characteristic parameters of NC such as threshold of absorbance and the position of the absorption edge on the concentration of the OOC in NC, etc., were determined. The light displacement of threshold absorption to infrared region was observed with increasing of concentration of coordinated material in NC. It was established that the excitation spectrum at which the photoluminescence in NC take place cover the range of wavelength from 200 to 410 nm. The PL of nanocomposites was detected as specific for internal transitions 4f–4f of the Eu 3+ ion 5 D 0 → 7 F i ( i = 0,1,2,3 and 4) centred at 537, 580, 615, 650 and 702 nm, respectively at T = 300 K. The dominant PL was observed at 615 nm and its halfwidth is less than 10 nm. The intensity of photoluminescence at 615 nm of NC is 2 times higher than the value of intensity of PL of Eu(TTA) 2 (Phen 3 PO) 2 NO 3 powders at equal conditions of excitation.