The luminescent properties of 1 mol % Eu(3+) -doped cubic Lu(2)O(3) nanocrystals prepared by a combustion synthesis route were investigated. The visible emission spectrum of the europium doped Lu(2)O(3) nanocrystals indicate that the structural environment surrounding the dopant Eu(3+) ion is distorted when compared to a bulk sample with a micrometer particle size. From the resulting emission spectra, the Omega(2) and Omega(4) Judd-Ofelt intensity parameters were calculated. The lifetimes of the (5)D(0) excited state for both the C(2) and C(3i) sites were found to be nearly double that found for a similarly doped sample with larger particle size (bulk sample). This behavior is attributed to a change in the refractive index of the nanocrystalline material that in turn modifies the oscillator strength of the 4f <----> 4f transitions.
Variation of fluorescence lifetimes and Judd-Ofelt parameters between Eu3+ doped bulk and nanocrystalline cubic Lu2O3
SPEGHINI, Adolfo;BETTINELLI, Marco Giovanni
2004-01-01
Abstract
The luminescent properties of 1 mol % Eu(3+) -doped cubic Lu(2)O(3) nanocrystals prepared by a combustion synthesis route were investigated. The visible emission spectrum of the europium doped Lu(2)O(3) nanocrystals indicate that the structural environment surrounding the dopant Eu(3+) ion is distorted when compared to a bulk sample with a micrometer particle size. From the resulting emission spectra, the Omega(2) and Omega(4) Judd-Ofelt intensity parameters were calculated. The lifetimes of the (5)D(0) excited state for both the C(2) and C(3i) sites were found to be nearly double that found for a similarly doped sample with larger particle size (bulk sample). This behavior is attributed to a change in the refractive index of the nanocrystalline material that in turn modifies the oscillator strength of the 4f <----> 4f transitions.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
