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Photoluminescence properties of ZrO2:Gd3+, ZrO2:Gd3+ – Dy3+ and ZrO2:Gd3+ – Yb3+ phosphors by Pechini method

Yildiz E.

Materials Science Poland

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2018

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Vol. 36, No. 1

157--161

EN

Zr0.99Gd0.01O2, Zr0.98Gd0.01Dy0.01O2 and Zr0.99Gd0.01Yb0.1O2 phosphors were synthesized by Pechini method at 1200 °C for 12 h in air. The phosphors were characterized by using X-ray powder diffraction (XRD), differential thermal analysis/thermal gravimetry (DTA/TG), scanning electron microscopy (SEM) and photoluminescence spectrofluorometer (PL). X-ray powder diffraction studies showed that the phosphors were crystallized as monoclinic and tetragonal multiphases. The particle size of the phosphors after heat treatment at 1200 °C was found to be of 200 nm to 250 nm. Luminescence studies on these phosphors have been carried out on the emission and excitation, along with lifetime measurements. The results of emission analysis indicate that the phosphors are expected to find potential applications as new optical materials.

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Influence of Dy Doping on the Properties of BiFeO3

Dzik J., Feliksik K., Pikula T., Panek R., Rerak M.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 3

1351--1355

EN

The aim of this research was to fabricate and study the properties of Bi1-x DyxFeO3 (for x = 0, 0.05, 0.07, 0.1) ceramics materials. Simple oxide powders Bi2O3, Dy2O3 and Fe2O3 were used to fabricate Bi1-xDyxFeO3 ceramics by mixed oxide method followed by free sintering. The study presents changes in microstructure and crystal structure as well as in dielectric properties and magnetic properties caused by modification of BiFeO3 with dysprosium dopant.

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Excitability of high-energy ultraviolet radiation for Dy3+ in antimony phosphate glasses

Zhu C., Zhang J., Wang Z., Lin H.

Materials Science Poland

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2017

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Vol. 35, No. 2

346--354

EN

Dy3+ doped antimony phosphate (ZASP) glasses are synthesized and the specificity of the luminescence behavior is demonstrated. Different from the conventional long-wave ultraviolet (UVA) exciting cases, the excitable area of Dy3+ doped ZASP glasses is extended to high-energy ultraviolet radiation including medium-wave ultraviolet (UVB) and short-wave ultraviolet (UVC) spectral regions. The quantum efficiency for 4F9/2 level of Dy3+ in low- and medium-concentration Dy2O3 doping cases reaches 95.0 % and 66.7 %, respectively, confirming the emission effectiveness from Dy3+ in ZASP glasses. The values of energy-transfer probability (P) have obvious difference while using 340 nm and 540 nm as monitoring wavelengths, so asthe energy-transfer efficiencies (η), which are related to the energy-transfer processes from discrepant Sb3+ donors to Dy3+ acceptors, were in-equivalent. The effective excitability of high-energy ultraviolet radiation illustrates that Dy3+ doped ZASP glasses are a promising candidate in developing visible light sources, display devices and tunable visible lasers.

4

Study on the Photochromic Properties of Coloured Luminous Fibres Based on PA6

Yan Y., Zhu Y., Ge M.

Fibres & Textiles in Eastern Europe

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2016

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Vol. 24, no. 3 (117)

38--43

EN

Coloured PA6 luminous fibres were prepared by adding luminous material and inorganic pigments. The morphology and optical properties of the coloured PA6 luminous fibres were characterized. The results revealed that luminous materials were dispersed uniformly in the fibres without obvious agglomerates. The yellow inorganic pigment and luminous material might induce a reduction in the PA 6 fibre crystallization degree. The luminous fibres emitted long-lasting phosphorescence with an excitation peak at 360 nm and emission peak at 515 nm. However, the excitation spectrum of the PA6-Y exhibited three peaks. The decay curves revealed that the yellow inorganic pigment enhanced the brightness of PA6 luminous fibres. The PA 6 luminous fibres had low colour purities and a high colour rendering index. There was no obvious difference among the emissive colours of the luminous fibres, and the colours of luminous fibres were similar to those of the pigments added.

PL

Barwione luminescencyjne włókna PA6 przygotowano przez dodanie materiałów luminescencyjnych i pigmentów nieorganicznych. Scharakteryzowano właściwości morfologiczne i optyczne barwionych luminescencyjnych włókien PA6. Wyniki wykazały, że materiały luminescencyjne były rozproszone równomiernie we włóknach bez widocznych aglomeratów. Żółte pigmenty nieorganiczne i materiał luminescencyjny mogą powodować obniżenie stopnia krystalizacji włókien PA6. Włókna luminescencyjne emitowały długotrwałą fosforescencję z pikiem drgań przy 360 nm. Krzywe zaniku wykazały, że żółty pigment nieorganiczny zwiększa jasność luminescencyjnych włókien PA6. Luminescencyjne włókna PA6 charakteryzowały się niską czystością kolorów i wysokim współczynnikiem oddawania barw. Nie stwierdzono żadnej różnicy pomiędzy kolorami emisji luminescencyjnych włókien; barwy luminescencyjnych włókien były podobne do barwy dodanych pigmentów.