Group III element substitution effects on Eu‐doped thiogallate phosphors

Abstract

Photoluminescence properties of II‐III2S4:Eu (II=Ca, Sr, Ba; III=Ga, In, Y, La; Eu concentration was 1 mol%) have been investigated systematically. In Ga compounds, well‐known green∼yellow emissions are observed, while the emissions become very weak in In substituted compounds. In III=Y or La compounds, when II=Ca or Sr, red∼infrared emissons which seem to be due to phonon‐terminated transition of the Eu2+ ions are observed, while when II=Ba, strong sharp lines due to the Eu3+ions are detected. These spectral changes are discussed in terms of the effective ionic radii and the sulfur vacancies (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Color Tuning of Light Emitted from the Cathodoluminescence of (Ca1 − xEux)Ga2S4 Phosphors

“…Similarly, the lattice parameters of EuGa 2 S 4 are a = 2.0716 nm, b = 2.0404 nm, c = 1.2200 nm 28 . The Eu 2+ ions are expected to occupy the Ca 2+ site in the (Ca 1‐ x Eu x )Ga 2 S 4 phosphors because the ionic radius of Eu 2+ (0.125 nm) differs only slightly from that of Ca 2+ (0.112 nm) when both ions are in eightfold coordination 29 . The Rietveld‐refined cell parameters of the Ca 0.9 Ga 2 S 4 :0.1Eu phosphor investigated in the present work are a = 2.0136 nm, b = 2.0056 nm, c = 1.2109 nm in orthorhombic geometry with D 2h 24 ‐ Fddd symmetry.…”

“…28 The Eu 2+ ions are expected to occupy the Ca 2+ site in the (Ca 1-x Eu x )Ga 2 S 4 phosphors because the ionic radius of Eu 2+ (0.125 nm) differs only slightly from that of Ca 2+ (0.112 nm) when both ions are in eightfold coordination. 29 Figure 4. This result is attributed to the CL intensities depending on the volume of electrons penetrating the phosphors.…”

Highly Luminescent Multicomponent Green Phosphor for a White Light‐emitting Diode

“…Kato et al . synthesized Eu 2+ ‐doped MY 2 S 4 (M = Ca, Sr, and Ba) phosphors . They found that the calcium or strontium thioyttrate phosphors, when excited at 500 nm, produced red and near‐infrared emissions, respectively.…”

“…Kato et al synthesized Eu 2+ -doped MY 2 S 4 (M = Ca, Sr, and Ba) phosphors. 10 They found that the calcium or strontium thioyttrate phosphors, when excited at 500 nm, produced red and near-infrared emissions, respectively. In this study, we extended the chemical composition of the green phosphor to (Zn 0.6 Sr 0.3 Mg 0.1 ) 2 Ga 2 M x S 5+3x/2 :Eu 2+ (M = Group 3 trivalent ion) and investigated the incorporation effects of trivalent ions (Sc 3+ , Y 3+ , or La 3+ ) on the luminescence properties.…”

Photoluminescence properties of Eu2+‐activated thiogallate phosphors

“…Therefore, Eu 2+ ‐activated thiogallates are likely to be applied in various fields in the future. However, the literature contains only a few studies on the properties of Eu 2+ ‐activated thiogallates 27–34 . In this account, we systematically analyze Eu 2+ ‐activated thiogallates.…”