Combinatorial Search for New Red Phosphors of High Efficiency at VUV Excitation Based on the YRO₄ (R = As, Nb, P, V) System

Abstract

On the basis of the possibility that there might exist a mixed composition of the Y(As,Nb,P,V)O4 system of better luminescent performance than the single-compound phosphors at the VUV excitation, a solution combinatorial chemistry synthesis and characterization was employed in the present investigation. Quaternary and ternary combinatorial libraries were designed to implement an efficient screening process. In parallel, the first-principle calculations were also carried out on the basis of the density functional theory to give a reasonable interpretation to the results from the combinatorial chemistry screening process. It was found that a new phosphor, Y0.9(P0.92V0.03Nb0.05)O4:Eu3+, which was obtained through the three-step combinatorial screening, shows promising luminance and CIE color chromaticity that could be comparable to the commercially available red phosphor used for the PDP application. As a result of the luminescent mechanism study in association with the calculated density of states (DOS), the entire energy transfer route under the 147-nm excitation was revealed for the newly found phosphor, Y0.9(P0.92V0.03Nb0.05)O4:Eu3+.

Observation of intermediate bands in Eu3+ doped YPO4 host: Li+ ion effect and blue to pink light emitter

“…Its value varies between ∼0.9-4.0 in some glass systems and ∼7-10 in CaMoO 4 hosts. 3,45,46 Sohn et al 27 reported the effect of excitation wavelengths at ∼147 nm (host excitation) and 254 nm (Eu-O CT excitation)) on emission intensity and A 21 31 found the higher luminescence intensity at electric dipole transition than that at magnetic dipole transition in glass-ceramic having Eu 3+ doped YPO 4 nano crystals. In addition to Eu 3+ they found the presence of Eu 2+ in glass matrix which results broad emission peak centered at ∼436 nm due to the 5d-4f transition of Eu 2+ .…”

“…2,25,26 But in some cases, the intensity of electric dipole transition is predominant over magnetic dipole transition in Eu 3+ doped (Y/La)PO 4 /YPO 4 .nH 2 O, which is expected from the theoretical view on site symmetry of Y 3+ where Eu 3+ ions occupy. [27][28][29][30][31][32] Existence of intermediate bands observed in YPO 4 system has not been discussed much in literature. This understanding will be useful in transfer process from such intermediate bands to Eu 3+ .…”

Preparation of nano phosphors by Microwave-assisted combustion synthesis

“…Most inorganic compounds doped with rare earth ions form an important class of phosphors as they possess a few interesting characteristics such as excellent chemical stability, high luminescence efficiency, and flexible emission colors with different activators [8,9]. Rare earth ions-activated nano structured materials have been attracting much interest in the past few years, due to the excellent luminescence and potential applications in luminescent devices and display equipment, such as lighting, field emission display (FED), cathode ray tubes (CRT), and plasma display panels (PDP) [10][11][12][13][14][15].…”

Colorless Transparent Fluorescence Material at the VUV Excitation: The Leached Sintered Glass with Impregnation of Tb3+ Ions

“…With the goal of exploring efficient VUV-excited luminescent materials, the luminescent properties of rare earth ions in different hosts have been intensively investigated in recent years. [1][2][3][4][5] Oxide glass is an attractive host matrix for emission ions because it has excellent optical and mechanical properties, is very stable in chemistry, and can be easily manufactured. However, as far as VUV-excited luminescent materials are concerned, glasses are hardly used as hosts because of the strong absorption of the glass matrix in the VUV wavelength region.…”

“…Glass with the composition 7.7Na 2 O . 4 C for 3 h in a platinum crucible. The glass was broken down and ball-milled into small and even fragments.…”