Preparation and energy transfer of Y2O3:Tb, Eu nanophosphors

ESTE5 – POSTERS
P84
Preparation and energy transfer of Y2O3:Tb, Eu nanophosphors
T.K. Anha , N. Vua , Ch. Barthoub, W. Strekc and L.Q. Minha
a
Institute of Materials Science, NCST of Vietnam, Hoang Quoc Viet Road, Hanoi, Vietnam,
E-mail: [email protected]
b
Institute of Low Temprature and Structure Reseach,Trzebiatowski Institute Polish Academy of Sciences,
Wroclaw, Poland
c
Laboratoire d’Optique des Solides UMR 7601,Universite Pierre et Marie Curie, 4 Place Jussieu, Paris, France
The Y2 O3 : Tb, Eu nanophosphors were prepared in our laboratory by the combustion method
for the optimal concentration of rare earth ions RE (Tb+Eu) 5 mol%, with the mole ratio of
Eu/Tb are 7/3, 8/2 and 9/1. The optical properties such as luminescent spectra and decay times
were measured in order to study the energy transfer between Tb and Eu. The effect of
concentration as well as influence of annealing temperature were investigated. The
luminescent intensity is maximum in the case of (Y0.95 Eux Tby )2 O3 nanophosphors (x+y =0.05,
x/y =8/2) annealing 600°C, 30 minute is due to energy transfer between Tb to Eu. The
lifetimes of the 5 D0 !7 F2 transition of Eu at about 612 nm are 940 µs, 650 µs and 360 µs for
the mole ratio of Eu/Tb 9/1, 8/2 and 7/3 respectively. The lifetimes of Tb (5 D4 !7 Fj) 545 nm
are 400 µs and 175 µs for the ratio of Eu/ Tb 9/1 and 8/2 respectively. The energy transfer in
the samples annealing 600°C is stronger than that in the samples annealing 700°C. The size
effect will be investigated in order to determine optimal condition for prepare nanophosphors.