Spectroscopic analysis of Eu3+doped silica-titania-polydimethylsiloxane hybrid ORMOSILs

Abstract

Eu3+doped silica-titania-polydimethylsiloxane hybrid ORMOSILs were synthesizedviaa non-hydrolytic sol-gel route. The structural and thermal analyses of the samples confirmed that the matrix structure remains unaffected by doping with different concentrations of Eu3+ions. Photoluminescence (PL) studies performed at 394 nm on Eu3+doped ORMOSILs imply that they emit broad blue host emission and the characteristic Eu3+red emissions simultaneously. Also, the samples were excited at the charge transfer (CT) band and this confirmed the existence of an energy transfer path from the host to the Eu3+ionsviaTi4+-O2−-Eu3+bonds. The phonon energy of the host matrix was estimated by phonon sideband (PSB) analysis and the results were substantiated by Raman analysis. Judd-Ofelt (JO) parameters were also evaluated which give details about the local surroundings of the Eu3+ions in the system and these parameters were further used for predicting the radiative properties of5D0→7F1,2,4transitions of Eu3+ions. Furthermore, the quantum efficiency and CIE co-ordinates were evaluated and it was found that Eu3+doped silica-titania-polydimethylsiloxane ORMOSIL has an intense pinkish red emission with a quantum efficiency of 30.7%.