Luminescent properties and reduced dimensional behavior of hydrothermally prepared Y2SiO5:Ce nanophosphors

Abstract

Hydrothermally prepared nanophosphor Y2SiO5:Ce crystallizes in the P21∕c structure, rather than the B2∕b structure observed in bulk material. Relative to bulk powder, nanophosphors of particle size ∼25–100nm diameter exhibit redshifts of the photoluminescence excitation and emission spectra, reduced self absorption, enhanced light output, and medium-dependent radiative lifetime. Photoluminescence data are consistent with reduced symmetry of the P21∕c structure and are not necessarily related to reduced dimensionality of the nanophosphor. In contrast, medium-dependent lifetime and enhanced light output are attributed to nanoscale behavior. Perturbation of the Ce ion electric field is responsible for the variable lifetime.

Effects of Tb doping on the photoluminescence of Y2O3:Tb nanophosphors

“…As one consequence, polymorphism can be induced in nanostructured materials [2]. For example, the observed red shift, with respect to bulk, in the photoluminescence (PL) emission of Y 2 SiO 5 :Ce nanopowders is due to polymorphism [3]. The latter effect is manifested as a twofold increase in the nanophosphor oscillator strength, as measured from the variation of the measured lifetime with the index of refraction of the embedding medium [3].…”

Thermoluminescence and Photoluminescence Study of Erbium Doped CaY2O4 Phosphor

“…The study of relatively deep trapping defect-states in various phosphors, as well as TL dating of solid state materials, is closely related to the position of the trapping levels within the forbidden gap. However, there are various methods to obtain the number of glow peaks in the complex glow curves and their kinetic parameters that best describe the peaks [9][10][11]. Here the order of kinetics shows general order which nearly goes to second order.…”

Synthesis and luminescence properties of microemulsion-derived Y3Al5O12: Eu3+ Phosphors

“…When excited at 147 nm by discharged Xe gas, few phosphors have shown the potential for plasma display panels applications [1]. The phosphors used in PDP include BaMgAl 10 O 17 : Eu 2+ and Y 2 SiO 5 : Ce 3+ for blue emission, BaAl 12 O 19 : Mn 2+ and Zn 2 SiO 4 : Mn 2+ for green emission, and YBO 3 : Eu 3+ for red emission [7][8][9][10][11][12]. In most of the earlier reports, UV-light sources have been used to analyze the luminescence properties of the phosphors; however, rare studies have involved observations on VUV-excited emission.…”