Solid state lighting and display application of Eu3+/Ag doped SiO2-ZrO2 sol-gel nanocomposites

Plasmon-assisted rare-earth oxide glasses have attracted substantial notice in solid-state lighting and display applications. In this work, Eu3+ doped SiO2-ZrO2 nanocomposites with varying concentration of Ag nanoparticles were prepared successfully by non-hydrolytic sol–gel process. After annealing the samples at 800 °C and the luminescence behaviour of the synthesized samples are analysed. TGA analysis confirmed the substantial removal of organic residues below 500 °C ensuring thermal stability of the samples. FTIR spectrum showed the generation of Si–O-Zr linkage, which was the confirmation of formation of SiO2-ZrO2 matrix. XRD and TEM analysis indicate that the plasmonic nanoparticles of Ag are successfully incorporated within the predominantly amorphous SiO2-ZrO2 network. Photoluminescence studies showed a pronounced enhancement in the emission intensity of Eu3+ ions for the samples embedded with Ag nanoparticles, arising from the localized surface plasmon-assisted electric field enhancement. An optimum concentration of Ag doping for maximum luminescence intensity was found out to be 0.5 wt% with quenching thereafter. Concurrently, prolonged decay lifetime was obtained for Ag embedded sample suggesting suppression of non-radiative decay pathways governed by the host rather than the plasmon-induced radiative rate increase. CIE plot shows that the chromaticity co-ordinates lie in the red region with minimal variation which demonstrates excellent color stability, with a color purity of 99.8%. The combined plasmon-assisted excitation and host-controlled relaxation suggest that synthesized nanocomposites are highly suitable for thermally stable solid-state lighting and display applications.