In this study, Li6 Y1-x Eux (BO3 )3 phosphor was successfully synthesized using a modified solid-state diffusion method. The Eu(3+) ion concentration was varied at 0.05, 0.1, 0.2, 0.5 and 1 mol%. The phosphor was characterized for phase purity, morphology, luminescent properties and molecular transmission at room temperature. The XRD pattern suggests a result closely matching the standard JCPDS file (#80-0843). The emission and excitation spectra were followed to discover the luminescence traits. The excitation spectra indicate that the current phosphor can be efficiently excited at 395 nm and at 466 nm (blue light) to give emission at 595 and 614 nm due to the (5) D0  → (7) Fj transition of Eu(3+) ions. Concentration quenching was observed at 0.5 mol% Eu(3+) in the Li6 Y1-x Eux (BO3 )3 host lattice. Strong red emission with CIE chromaticity coordinates of phosphor is x = 0.63 and y = 0.36 achieved with dominant red emission at 614 nm the (5) D0  → (7)  F2 electric dipole transition of Eu(3+) ions. The novel Li6 Y1-x Eux (BO3 )3 phosphor may be a suitable red-emitting component for solid-state lighting using double-excited wavelengths, i.e. near-UV at 395 nm and blue light at 466 nm. Copyright © 2015 John Wiley & Sons, Ltd.

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A series of Na (SO ) F Cl phosphors doped with Ce ions was prepared using the wet chemical method. X-Ray diffraction studies were used to determine their phase formation and purity. Fourier transform infrared spectroscopy effectively identified the chemical bonds present in the molecule. The photoluminescence properties of the as-prepared phosphors were investigated and the Ce ions in these hosts were found to give broadband emission in the UV range. For the thermoluminescence study, phosphors were irradiated with a 5 Gy dose of γ-rays from a Co source. Chen's half-width method was employed to calculate the trapping parameters from the thermoluminescence glow curve. Copyright © 2016 John Wiley& Sons, Ltd.

New series of blue light emitting diphenylquinoline (DPQ) and its derivatives based on Chlorine-Methoxy (Cl-MO-DPQ) and Chlorine-Methyl (Cl-M-DPQ) were synthesized in Argon atmosphere at 140˚C by Friedlander condensation. These all samples were soluble in many organic solvents like Acetic acid, Formic acid, Dichloromethane etc. in different molar concentrations up to micro molar. It emits blue light in above solvents under UV source. All samples in different organic solvents were studied. Structural characterization was made by FTIR. Ultraviolet, fluorescence and excitation spectroscopy were used for analysis of photo physical properties. Thermal properties were characterized by TGA and SDTA. The derivatives Cl-MO-DPQ and Cl-M-DPQ show absorbance peaks in the range 264 -370 nm and 264 -338 nm respectively. In both the cases the emission spectra are in blue region. The TGA and SDTA studies show not only the DPQ but also it's derivatives have good thermal stability even though they are low molecular weight organic compounds, which may in turn improve the stability and operating lifetime of the device. The physical and chemical properties of these polymers are useful as a blue emitting organic material for OLED's.

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A Series of blue emitting organic phosphors and its derivatives with different combinations were synthesized in an argon atmosphere at 1400C by Friedlander Condensation method and are tested chemically for its solubility in acidic and basic and emitting blue color under UV. The structural changes take place in DPQ an organic phosphor. The structural, optical and chemical properties of all the derivatives of diphlnylquioline (DPQ) were studied from various characterizations. It shows the stability of characterized organic polymers. The physical and chemical study shows more effectiveness with large applications to emit blue light for organic display system.