Tunable optical properties and DFT calculations of RE3+ codoped LaBO3 phosphors

Date

2019-12-01

Author

Yılmaz, Ayşen
Esentürk, Okan

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

194
views

0
downloads

In this study, single phase DyxLa1-xBO3, DyxCeyLa1-x-yBO3, DyxEuyLa1-x-yBO3, and TbxCeyLa1-x-yBO3 phosphors were successfully synthesized through the microwave assisted solid state method with urea. Synthesized compounds were characterized by X-Ray Diffraction, Fourier Transform Infrared spectroscopy, Scanning Electron Microscope, and Fluorescence spectroscopy. Thermal stabilities of the phosphors were studied with temperature dependent fluorescence measurements. In addition, density functional theory calculations were performed to investigate preferential Dy3+ ion doping sites in LaBO3 lattice. The findings of the study revealed over ten times increase in the emission intensities of phosphors were observed with Ce3+ codoping. The highest luminescence intensities were recorded for Dy0.09Ce0.05La0.86BO3 and Tb0.07Ce0.05La0.88BO3 phosphors. Furthermore, energy transfers were supported by luminescence lifetime measurements. Temperature dependent fluorescence measurements showed their thermal stabilities. According to the CIE 1931 color space, the colors of the Dy3+ only doped, Ce3+/Dy3+; Ce3+/Tb3+ and Dy3+/Eu3+ codoped phosphors were determined as off-white, white, green and yellow-orange, respectively. Intensities of the bands and the colors of the phosphors can be tuned with the choice of codopant ions or with adjustments in their concentration ratio.

Subject Keywords

Lanthanum orthoborate, Terbium, Cerium, Rare earth luminescence, Solid state lighting

URI

https://hdl.handle.net/11511/32616

Journal

OPTICAL MATERIALS

DOI

https://doi.org/10.1016/j.optmat.2019.109487

Collections

Graduate School of Natural and Applied Sciences, Article

Suggestions

OpenMETU
Core

Tunable optical properties and DFT calculations of RE3þcodoped LaBO3 phosphors Abacı, Özde Ceren; Esentürk, Okan (2019-12-01) In this study, single phase DyxLa1-xBO3, DyxCeyLa1-x-yBO3, DyxEuyLa1-x-yBO3, and TbxCeyLa1-x-yBO3 phosphors were successfully synthesized through the microwave assisted solid state method with urea. Synthesized com-pounds were characterized by X-Ray Diffraction, Fourier Transform Infrared spectroscopy, Scanning Electron Microscope, and Fluorescence spectroscopy. Thermal stabilities of the phosphors were studied with temperature dependent fluorescence measurements. In addition, density functional theory calc...
Nanoscale Thermal Transport in Single, Bilayer Graphene, and Graphite Gholivand, Hamed; Donmezer, Nazli (2016-10-12) In this study, ab-initio calculations were performed to obtain phonon dispersions of single, bilayer graphene, and graphite structures. Using these dispersions single mode relaxation times, thermal conductivities, and mean free paths (MFPs) have been calculated. Finally, calculated variables were used to understand the effects of additional layers to thermophysical properties, phonon mode contributions to thermal conductivity, and the limits for ballistic-diffusive heat transfer of single, bilayer graphene,...
LANTHANUM DOPED DICALCIUM PHOSPHATE MIXED WITH GRAPHENE OXIDE BONE CEMENTS AS A POTENTIAL MATERIAL IN BIOMEDICAL APPLICATIONS Motameni, Ali; Evis, Zafer; -, -; Department of Engineering Sciences (2021-9-06) In this thesis, mesoporous particles of β-tricalcium phosphate (βTCP, βCa3(PO4)2) and lanthanum (La) doped βTCP were synthesized by wet precipitation method attached with a microwave refluxing system. Pure dicalcium phosphate (DCP) and La modified dicalcium phosphate (La-DCP) bone cements were prepared based on acid/base reaction between βTCP (or La- βTCP) and monocalcium phosphate monohydrate (MCPM) in the presence of water. DCP bone cements were also mixed with 1.5-3.5wt.% of graphene oxide (GO). The obta...
Energy transfer and stimulated emission dynamics at 1.1 mu m in Nd-doped SiNx Li, Rui; Yerci, Selçuk; Kucheyev, Sergei O.; van Buuren, Tony; Dal Negro, Luca (2011-03-14) Neodymium (Nd) doped amorphous silicon nitride films with various Si concentrations (Nd:SiNx) were fabricated by reactive magnetron co-sputtering followed by thermal annealing. The time dynamics of the energy transfer in Nd:SiNx was investigated, a systematic optimization of its 1.1 mu m emission was performed, and the Nd excitation cross section in SiNx was measured. An active Nd:SiNx micro-disk resonator was fabricated and enhanced radiation rate at 1.1 mu m was demonstrated due to stimulated emission at ...
Magnetic properties and hyperfine interactions of Co1-2xNixMnxFe2O4 nanoparticles Baykal, A.; Eryiğit, Sümeyra; TOPKAYA, RAMAZAN; GÜNGÜNEŞ, HAKAN; Amir, Md.; YILDIZ, AYLİN; Kurtan, U.; Shirsath, Sagar E. (2017-04-15) Col-2xNixMnxFe2O4 (0.0 <= x <= 0.5) nanoparticles (NPs) were prepared via citrate assisted microwave combustion route. XRD analysis confirmed the cubic structure (spinel) of all samples. Average crystallite size of products (obtained from (311) diffraction line) was in the range of 32.9-43.4 nm. The intense peak appearing at around 531 cm(-1) in FT-IR was attributed to the formation of a spinel ferrite. Magnetic properties of the products were investigated by room temperature vibrating sample magnetometer a...

Citation Formats

A. Yılmaz and O. Esentürk, “Tunable optical properties and DFT calculations of RE3+ codoped LaBO3 phosphors,” OPTICAL MATERIALS, pp. 0–0, 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/32616.