| Title | Systematic study of sensitized LaF3: Eu3+ nanoparticles |
| Publication Type | Journal Article |
| Year of Publication | 2011 |
| Authors | Janssens, S., Williams G.V.M., and Clarke D.J. |
| Journal | Journal of Applied Physics |
| Volume | 109 |
| Issue | 2 |
| Date Published | 2011 |
| ISSN | 00218979 (ISSN) |
| Keywords | Judd-Ofelt parameters, Magnetic dipole transition, Nanomagnetics, Nanoparticle sizes, Nanoparticles, Non-radiative recombinations, Oleic acid, Optical amplifications, Optical study, Photoluminescence intensities, PL intensity, PL lifetime, Raman active modes, Stimulated emission cross section, Systematic study, Thenoyltrifluoroacetone, Unit-cell volume |
| Abstract | We have performed a systematic structural, vibrational, and optical study of LaF3: Eu3+ nanoparticles capped with oleic acid (OA) or OA and sensitized with thenoyltrifluoroacetone (TTA). The average nanoparticle size was around 11 nm for all Eu3+ concentrations. A shift in the energy of the Raman active modes is observed with increasing Eu3+ concentration that can be accounted for by a decrease in the unit cell volume. Sensitization by TTA was observed and resulted in an 18 000% increase in the photoluminescence (PL) intensity for TTA/OA capped LaF3: Eu3+ nanoparticles when compared with OA capped LaF3: Eu3+ nanoparticles. There is also a large increase in the D50 → F7 2 PL intensity, when normalized to the D5 0 → F7 1 PL magnetic dipole transition intensity, for TTA/OA capped nanoparticles. The changes in the PL intensities, PL lifetimes, Judd-Ofelt parameters, stimulated emission cross sections, and quantum efficiencies, for OA and TTA/OA capped LaF3: Eu3+ nanoparticles with increasing Eu3+ concentration can be accounted for by a model that separates the Eu3+ sites into sites near the surface and Eu3+ sites in the core as well as nonradiative recombination sites near the surface. The large increase in PL intensity due to TTA sensitization means that TTA capped LaF3: Eu3+ can potentially be used for applications that include optical amplification. © 2011 American Institute of Physics. |
| URL | http://www.scopus.com/inward/record.url?eid=2-s2.0-79551660131&partnerID=40&md5=54e72551d9b30f381d6ef5007263bacf |
| DOI | 10.1063/1.3531994 |
