Silver nanoparticles enhanced luminescence of dysprosium ions doped silica sol-gel

Silver (Ag) nanoparticles/dysprosium (Dy3+) 3 + ) ions co-doped in silica Xerogel having the composition of 5Ag-5Dy90SiO2 (mol%) have been prepared using the sol-gel method. Spectral diagnosis of Ag NPs in both collide solutions and silica Xerogels shows a typical surface plasmon resonance (SPR) band centered around 431 nm and 426 nm, respectively. The nanoscale and polycrystalline structure of AgNPs was revealed through FE-SEM and XRD. Fourier transform infrared spectroscopy (FTIR) analysis illustrates the distribution of these ions (Ag, Dy3+) 3 + ) in the porous structures of silica Xerogels, in which this spectrum did not display bands arising from the bonding of such ions with the silica structure. The absorption and photoluminescence (PL) spectra, as a function of Dy3+ 3 + concentrations, have been recorded at room temperature. Prominent emission bands of Dy3+ 3 + ions have been observed for 4F9/2 F 9/2-* 6H13/2: H 13/2 : 575 nm and 4F9/2 F 9/2-* 6H15/2: H 15/2 : 482 nm at 350 nm excitation. The PL of the Dy3+ 3 + doped and AgNPs/Dy3+ 3 + co-doped silica xerogel clearly showed that silver NPs improve the (PL) intensity of the Dy3+ions 3 + ions spectra, and this is due to the strong local electric field induced by SPR of silver NPs in order to energy transfer from the silver NPs to Dy3+ 3 + ions. The emission cross-section (aem.) and the radiative lifetime (brad) of the transtion4F9/2 4 F 9/2-* 6H13/2 H 13/2 have been determined for doped and co-doped samples. The white light emission has been investigated and observed through the Commission International deI'Eclairage (CIE) chromaticity diagram, where the colour coordinates are in the white range for all co-doped samples.