Red luminescence of Lu2O2S:Ce and Y2O2S:Ce at room temperature

Persistent luminescence in rare earth ion-doped gadolinium oxysulfide phosphors

“…1(b), is exhibited in almost all the samples except for Ce 3+ -doped one. The different excitation spectrum of Ce 3+ -doped sample is associated with its special [Xe]4f 1 electronic configuration [33]. Under 230 nm excitation, two broad emission bands originated from transition between the excited states and the 2 F 5/2 and 2 F 7/2 states can be observed in the Ce 3+ -doped sample, as shown in Fig.…”

Luminescence and X-ray absorption studies on 0.5% Ce3+ doped BaCa2MgSi2O8 phosphor

“…The results showed that Eu 2+ ions prefer to enter the Ba 2+ site, a certain amount of Eu 2+ ions can also enter the Ca 2+ site, giving rise to emissions at 430 nm (Ba 2+ site) and 460 nm (Ca 2+ site). In general, when Ce 3+ and Eu 2+ enter one specific site in the same host lattice, the emission energy of Eu 2+ and Ce 3+ can be related according to the following empirical equation: 35 E df (Eu 2+ ) = 0.64E df (Ce 3+ ) + 0.53 eV (1) From eqn (1), the emissions from Ce 3+ are roughly estimated to be 3.68 eV (B337 nm) and 3.38 eV (B367 nm) when it occupies the Ba 2+ and Ca 2+ sites, respectively. Thus the spectra should be mainly from Ce 3+ in the Ba 2+ site at this doping concentration.…”

“…Since crystal field and covalence can influence the location of 5d orbitals and to a lesser extent the 4f levels, the luminescence spectra of Ce 3+ can be tuned from ultraviolet to red regions depending on the host lattices. [1][2][3] During the past years, growing interests were focused on Ce 3+ based phosphors. Due to its relatively fast decay and excellent luminescence properties, Ce 3+ doped inorganic compounds have been commercially used in scintillators, lightings and displays.…”

Temperature quenching of Ce3+ impurity ion fluorescence in Y2O2S: Spatial confinement effect in multiphonon relaxation

“…Y 2 O 2 S:Ce 3+ (as well as YAG:Ce 3+ and Sc 2 O 3 :Ce 3+ ) is a luminescent material in which a broad electron–phonon emission band, that is due to fast (<100 ns) electric dipole allowed 4f 0 5d 1 –4f 1 radiative transition, occurs in the visible part of the optical spectrum 6, 7. Actually, in Y 2 O 2 S:Ce 3+ the spectral position of the 4f 0 5d 1 –4f 1 band is one of the lowest of all Ce 3+ doped materials 8.…”

“…6 only below 170 K, though some room temperature fluorescence was reported in Ref. 7. This is the reason why Y 2 O 2 S:Ce 3+ received much less attention: it does not look attractive from the point of view of applications for solid state lighting.…”