Luminescence properties of Eu3+ or Dy3+/Au co-doped SiO2 nanoparticles

Silica nanoparticles, prepared by the Stober method, have been doped with Eu3+, Dy3+, or processed to result in Au nanoparticles on the silica surface. The luminescence of the rare earth (RE)-doped SiO2 particles has been studied as a function of the nature of the RE, their concentration and also of the presence of Au nanoparticles at the surface of the SiO2 nanoparticles. We have shown that the Eu3+ emission is observable over the experimental conditions examined, whereas it was not possible to observe any emission for Dy3+ doped materials. No enhancement of the Eu3+ emission was observed following the adsorption of gold nanoparticles at the surface of the SiO2 nanoparticle, however an excitation at 250 nm leads to both the emission of the matrix and Eu3+ showing an energy transfer from the SiO2 matrix to Eu3+ ions.