Up-conversion luminescence of erbium (III) oxalate nanoparticles/titania/y-Glycidoxypropyltrimethoxysilane composite sol-gel thin films

Erbium (III) oxalate nanoparticles dispersed titania/y-Glycidoxypropyltrime thoxysilane composite materials for photonic applications were prepared by a chemical approach combining the microemulsion technique and the sol-gel m ethod at low temperature. Transmission electron microscopy observation show s that the size of the erbium (III) oxalate nanoparticles is in the range f rom 10 to 40 nm. A relatively strong room-temperature green up-conversion e mission at 543 nm (S-4(3/2) --> I-4(15/2)) has been measured for the compos ite thin films with different erbium oxalate content and heat treatment tem perature upon excitation at 993 nm. The lifetime of the visible up-conversi on emission has been measured. UV-visible transmission spectroscopy results showed that a relatively high transparency tin the visible range) composit e thin film could be obtained at a suitably low heat treatment temperature.