Luminescent nano-composites generated from a spray

Abstract

The spray-pyrolysis (SP) synthesis technique has been employed to obtain SiO 2:Eu 3+ and γ-AlOOH:Eu 3+. It was possible to obtain sub-micrometric spherical particles of SiO 2 with luminescent Eu 3+ ions bonded to the silica surface or embedded in amorphous silica beads, by controlling the synthesis and annealing process. Boehmite γ-AlOOH doped with Eu 3+ nanoparticles were synthesized by SP at moderate temperature (200 °C) with Eu 3+ ions bonded to the surface hydroxyls of the boehmite nanocrystals. Luminescent nano-composites were obtained by controlled reaction of γ-AlOOH:Eu 3+ nanocrystals with ASN (asparagine). In these nano-composites, the Eu 3+ are held at the surface of the boehmite nanocrystals and partially shielded from interactions with additional luminescence quenchers (hydroxyl groups, water molecules).