Synthesis, Structure, Morphology, and Luminescent Properties of Ba2MgWO6: Eu3+ Double Perovskite Obtained by a Novel Co-Precipitation Method

Eu3+ doped Ba2MgWO6 (BMW) double-perovskite was successfully synthesized for the first time by the co-precipitation method. The synthesis procedure, crystal structure, as well as morphology of obtained samples are presented. Domination of the 5D0–7F1 magnetic–dipole over forced electric–dipole transitions in the emission spectra indicates that Eu3+ ions are located in the high symmetry site with inversion center. Only one emission line assigned to the 5D0–7F0 transition was observed, confirming that europium substituted for only one host cation site. The photoluminescence excitation (PLE) spectrum is dominated by a strong and broad band related to the O2− → Eu3+ and O2− → W6+ charge transfer. The decay of the emission from the 5D0 and 5D1 levels was investigated. The temperature-dependent emission spectra showed that the T0.5 is equal to 350 K. Extinguishing mechanisms of the Eu3+ luminescence in the studied host are discussed.

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Study on Luminescent Properties of YAG:Ce3+, Gd3+/La3+ Prepared by Co-Precipitation Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1002.29 ◽

2014 ◽

Vol 1002 ◽

pp. 29-34

Author(s):

Rong Feng Guan ◽

Ya Jun You ◽

Juan Song ◽

Gui Hua Hou

Keyword(s):

Emission Intensity ◽

Room Temperature ◽

Thermal Quenching ◽

Luminescent Properties ◽

Ammonium Bicarbonate ◽

Color Temperature ◽

Precipitation Method ◽

Structure Morphology ◽

Relative Emission Intensity ◽

Co Precipitation

The YAG:Ce3+, Gd3+/La3+ yellow phosphors were prepared by co-precipitation method with 0.1mol/L ammonium bicarbonate and aqueous ammonia as precipitants, and the crystal structure, morphology, luminescent properties were investigated. The results indicated that the emission peaks of the YAG:Ce3+, Gd3+/La3+ were redshifted from 535nm to 545.5nm /547nm, and the relative emission intensity declined from 330nm to 145/132 with doping content of Gd3+ /La3+ increased from 0 to 0.9mol at room temperature. Compared with Gd-doping phosphors, the redshift of La3+-doping phosphor was larger and the relative emission intensity declined more quickly. Compared with YAG:Ce3+, the thermal quenching characteristics of YAG:Ce,Gd and YAG:Ce,La were noticeably worse when the temperature increased, but the extents of peak wavelength redshifts were almost the same, about is 7-8nm in the experimental temperature range (50-200°C), have little relation with the doping concentration change. Doping concentrations of Gd or La couldn't be too high, and the suitable concentration was less than 0.6mol at the regulating color temperature and color index.

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Structure, Luminescence, and Magnetic Properties of Crystalline Manganese Tungstate Doped with Rare Earth Ion

Materials ◽

10.3390/ma14133717 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3717

Author(s):

Jae-Young Jung ◽

Soung-Soo Yi ◽

Dong-Hyun Hwang ◽

Chang-Sik Son

Keyword(s):

Magnetic Field ◽

Rare Earth ◽

Sintering Temperature ◽

Luminescent Properties ◽

Concentration Quenching ◽

Rare Earth Ions ◽

Precipitation Method ◽

Rare Earth Ion ◽

Co Precipitation ◽

Quenching Phenomenon

The precursor prepared by co-precipitation method was sintered at various temperatures to synthesize crystalline manganese tungstate (MnWO4). Sintered MnWO4 showed the best crystallinity at a sintering temperature of 800 °C. Rare earth ion (Dysprosium; Dy3+) was added when preparing the precursor to enhance the magnetic and luminescent properties of crystalline MnWO4 based on these sintering temperature conditions. As the amount of rare earth ions was changed, the magnetic and luminescent characteristics were enhanced; however, after 0.1 mol.%, the luminescent characteristics decreased due to the concentration quenching phenomenon. In addition, a composite was prepared by mixing MnWO4 powder, with enhanced magnetism and luminescence properties due to the addition of dysprosium, with epoxy. To one of the two prepared composites a magnetic field was applied to induce alignment of the MnWO4 particles. Aligned particles showed stronger luminescence than the composite sample prepared with unsorted particles. As a result of this, it was suggested that it can be used as phosphor and a photosensitizer by utilizing the magnetic and luminescent properties of the synthesized MnWO4 powder with the addition of rare earth ions.

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Spherical BaMgAl10O17:Eu2+ Phosphor Particles by Liquid Phase Synthesis

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.124-126.391 ◽

2007 ◽

Vol 124-126 ◽

pp. 391-394

Author(s):

Ha Kyun Jung ◽

Dae Won Lee ◽

Yoon Chang Park

Keyword(s):

Liquid Phase ◽

Emission Intensity ◽

Broad Band ◽

Emission Spectra ◽

Luminescent Properties ◽

Phase Reaction ◽

Uniform Size ◽

Synthetic Process ◽

Preparation Conditions ◽

Blue Phosphor

To improve luminescent properties of the phosphor, spherical BaMgAl10O17:Eu2+ particles have been synthesized using a liquid phase reaction composed of two-stage precipitations. This phosphor particles exhibited uniform size (0.4 ㎛) with narrow distribution and were well-dispersed without agglomeration. The single phase of phosphor was formed by firing at the temperature of about 1350°C. The preparation conditions in this synthetic process for spherical BaMgAl10O17:Eu2+ particles were optimized on the basis of emission intensity by the excitation at 147 nm. The emission spectra showed the typical broad band due to the transition of Eu2+ activator from 4f65d1 to 4f7 in BaMgAl10O17:Eu2+. The maximum emission intensity for this spherical blue phosphor was obtained by reduction treatment at 1450°C.

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Study of Temperature Behavior of Luminescence Emission of LaVO4 and La1-xEuxVO4 Powders

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.230.153 ◽

2015 ◽

Vol 230 ◽

pp. 153-159 ◽

Cited By ~ 7

Author(s):

Oksana Chukova ◽

Sergiy G. Nedilko ◽

Sergiy A. Nedilko ◽

Tetiana Voitenko ◽

Olga Gomenyuk ◽

...

Keyword(s):

Emission Spectra ◽

Spectral Lines ◽

Temperature Behavior ◽

Precipitation Method ◽

Temperature Range ◽

Luminescence Emission ◽

Electron Transitions ◽

The Matrix ◽

Co Precipitation ◽

The Eu

The La1‑xEuxVO4 powders were synthesized by co-precipitation method. Emission spectra of the LaEuVO4 and La1‑xEuxVO4 powders consist of wide non-structural bands of the matrix emission and narrow spectral lines caused by inner f-f electron transitions in the Eu3+ ions, respectively. The both types of emission were studied within 8 – 300 K temperature range. Decomposition of spectra of the wide matrix emission on three bands has been carried out and temperature dependencies for each band were studied. Temperature behavior of the Eu3+ emission was investigated for lines assigned to different Eu3+ centres. Obtained dependencies are analyzed and discussed using proposed schemes of transitions in the VO43- groups and structure of the nearest surrounding of the Eu3+ emission centres.

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Annealing effects on luminescent properties of Eu3+ doped Gd2Zr2O7 nanopowders

Science of Sintering ◽

10.2298/sos1503269r ◽

2015 ◽

Vol 47 (3) ◽

pp. 269-272 ◽

Cited By ~ 4

Author(s):

M.S. Rabasovic ◽

D. Sevic ◽

J. Krizan ◽

M.D. Rabasovic ◽

N. Romcevic

Keyword(s):

Low Cost ◽

Emission Spectra ◽

Luminescent Properties ◽

Combustion Method ◽

Luminescence Properties ◽

Camera System ◽

Strong Emission ◽

Structure Morphology ◽

Annealing Effects ◽

Size And Morphology

In this report presented are structure, morphology and luminescence properties of nanopowders based on gadolinium zirconium oxide (Gd2Zr2O7) doped by europium ions (Eu3+). The nanopowders were prepared using a flame combustion method, the most frequently used process due to the simplicity and low cost of the synthesis procedures and also due to the possibility of tailoring the size and morphology of particles. The produced material is suitable for various optical devices. The luminescence properties of synthesized nanopowders were characterized by emission spectra and luminescence lifetimes obtained by using the streak camera system. Moreover, emission spectra were obtained and compared for powders as-obtained and after additional annealing at 1200o C. Luminescence emission spectra clearly show peaks characteristic for the strong emission lines at 611 nm and 630 nm corresponding to the 5D0 ? 7F2 long lived transition.

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Nitrogen and Bromide Co-Doped Hydroxyapatite Thin Films with Antimicrobial Properties

Coatings ◽

10.3390/coatings11121505 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1505

Author(s):

Simona Liliana Iconaru ◽

Carmen Steluta Ciobanu ◽

Daniela Predoi ◽

Mikael Motelica-Heino ◽

Constantin Cătălin Negrilă ◽

...

Keyword(s):

Thin Films ◽

Antimicrobial Activity ◽

Spin Coating ◽

Thin Layers ◽

Precipitation Method ◽

X Ray ◽

Co Precipitation ◽

First Time ◽

Co Doped

Hydroxyapatite (Ca10(PO4)6(OH)2, HAp), due to its high biocompatibility, is widely used as biomaterial. Doping with various ions of hydroxyapatite is performed to acquire properties as close as possible to the biological apatite present in bones and teeth. In this research the results of a study performed on thin films of hydroxyapatite co-doped with nitrogen and bromine (NBrHAp) are presented for the first time. The NBrHAp suspension was obtained by performing the adapted co-precipitation method using cetyltrimethylammonium bromide (CTAB). The thin layers of NBrHAp were obtained by spin-coating. The stability of the NBrHAp suspension was examined by ultrasound measurements. The thin layers obtained by the spin-coating method were examined by scanning electron microscopy (SEM), optical microscopy (OM), and metallographic microscopy (MM). The presence of nitrogen and bromine were highlighted by energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) studies. Fourier transform infrared spectroscopy (FTIR) was used to highlight the chemical status of nitrogen and bromine. In addition, the powder obtained from the NBrHAp suspension was analyzed by XRD. Moreover, the in vitro antimicrobial activity of the NBrHAp suspensions and coatings was investigated using the reference microbial strains Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Candida albicans ATCC 10231. The results highlighted the successful obtainment of N and Br co-doped hydroxyapatite suspension for the first time by an adapted co-precipitation method. The obtained suspension was used to produce pure NBrHAp composite thin films with superior morphological properties. The NBrHAp suspensions and coatings exhibited in vitro antimicrobial activity against bacterial and fungal strains and revealed their good antimicrobial activity.

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Fabrication and Luminescence Properties of CaMoO4:Eu3+ Red Phosphors for White LED

Materials Science Forum ◽

10.4028/www.scientific.net/msf.663-665.441 ◽

2010 ◽

Vol 663-665 ◽

pp. 441-444

Author(s):

Zhen Hua Liang ◽

Yu Zhi Feng ◽

Xiao Xia Liu ◽

Gui Hua Peng

Keyword(s):

Luminescent Properties ◽

Luminescence Properties ◽

Precipitation Method ◽

White Led ◽

Doping Amount ◽

Red Phosphors ◽

Co Precipitation ◽

The Relationship

CaMoO4: Eu3+ red phosphors were synthesized by co-precipitation method with H3BO3 as an additive and the relationship between H3BO3 doping amount and luminescent properties were studied. The brightness increased with increasing H3BO3 amount, the brightness of the CaMoO4: Eu3+ powder with 10 mol％ H3BO3 was 3.2 times higher than that of the phosphor without H3BO3.

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Structural and Optical Properties of Pure NiO Nanoparticles and NiO-Mn2O3, NiO-CdO, NiO-Pb2O3, NiO-ZnO Nanocomposites

Jordan Journal of Physics ◽

10.47011/14.5.2 ◽

2021 ◽

Vol 14 (5) ◽

pp. 409-417

Keyword(s):

Nickel Oxide ◽

Green Emission ◽

Hexagonal Structure ◽

Precipitation Method ◽

Nio Nanoparticles ◽

Structural And Optical Properties ◽

Suitable Material ◽

Structure Morphology ◽

Average Grain Size ◽

Co Precipitation

Abstract: Pure nickel oxide (NiO) nanoparticles and NiO-Mn2O3, NiO-CdO, NiO-Pb2O3, NiO –ZnO nanocomposites were synthesized by co-precipitation method. The PXRD studies revealed that NiO, Mn2O3 and CdO possessed cubic structure, Pb2O3 possessed monoclinic structure, ZnO possessed hexagonal structure and confirmed the presence of polycrystallinity nature of NiO and Mn2O3, CdO, Pb2O3, ZnO in the nanocomposites. The average grain size of NiO nanoparticles was found to be 30.10 nm using Debye Scherer’s formula. The FESEM images of NiO nanoparticles and their nanocomposites revealed spherical shaped structure and NiO-Pb2O3 revealed needle shaped rod-like structure. EDAX analysis confirmed the composition of NiO nanoparticles and their nanocomposites. Raman spectra exhibited characteristic peaks of pure NiO and that of NiO- Mn2O3, NiO-CdO, NiO- Pb2O3, NiO-ZnO in the synthesized nanocomposites. In the PL spectra, blue and green emission was observed in the samples. UV-vis spectra revealed the absorption peaks of NiO nanoparticles and their nanocomposites. Thus, the synthesized NiO- Mn2O3, NiO-CdO, NiO - Pb2O3 and NiO-ZnO nanocomposites can be a suitable material for electrocatalysis applications. Keywords: Nickel oxide nanocomposites, Structure, Morphology, Absorption, Luminescence.

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Synthesis of tin oxide activated by DAN grafting and Mo nanoparticle insertion for optoelectronic properties improvement

RSC Advances ◽

10.1039/c6ra21017a ◽

2016 ◽

Vol 6 (98) ◽

pp. 95405-95416 ◽

Cited By ~ 2

Author(s):

N. Bouazizi ◽

R. Bargougui ◽

A. Benghnia ◽

J. Vieillard ◽

S. Ammar ◽

...

Keyword(s):

Tin Oxide ◽

Optoelectronic Properties ◽

Precipitation Method ◽

New Material ◽

Co Precipitation ◽

First Time

Tin oxide (SnO2) was synthesized via a co-precipitation method and activated by 1,5 diaminonaphthalene (DAN) grafting and molybdenum nanoparticle (Mo-NPs) incorporation for the first time as a new material.

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