Structural, optical and morphological properties of La, Cu co-doped SnO2 nanocrystals by co-precipitation method

The objective of this study was to develop a novel silica modified large-sized hydroxyapatite whiskers with improved properties for use in bone repair applications. Large-sized whiskers with a mean length of 250μm were obtained by a hydrothermal co-precipitation method at 150°C, 7.5Mpa in high-pressure reactor. Silica modified hydroxyapatite whiskers were prepared by dissolving TEOS in ethanol solution, then sintering with hydroxyapatite. The compositional and morphological properties of prepared whiskers were studied by means of x-ray diffraction (XRD), Fouier transform infrared (FT-IR), scanning electron microscopy (SEM). The results indicated the evidence of nanosilicon dioxide particles on the surface of HAP whiskers. The size of nanosilicon dioxide particles depends on dropping and stirring rate. Hence, this new type of silica modified large-sized hydroxyapatite whiskers is a valuable candidate for biomedical applications.Key words: hydroxyapatite, hydrothermal co-precipitation, surface modified, whiskers

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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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Multidoped Ln3+ gadolinium dioxycarbonates as tunable white light emitting phosphors

Dalton Transactions ◽

10.1039/c6dt04629k ◽

2017 ◽

Vol 46 (9) ◽

pp. 2785-2792 ◽

Cited By ~ 11

Author(s):

I. Nelli ◽

A. M. Kaczmarek ◽

F. Locardi ◽

V. Caratto ◽

G. A. Costa ◽

...

Keyword(s):

Oxalic Acid ◽

White Light ◽

Precipitation Method ◽

Light Emitting ◽

Co Precipitation ◽

Co Doped

Gadolinium dioxycarbonates co-doped with different visible emitting lanthanides were synthesized via a co-precipitation method using oxalic acid as a precipitating agent.

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Photoluminescent enhancement with co-doped alkali metals in Gd2O3:Eu synthesized by co-precipitation method and Judd Ofelt analysis

Journal of Luminescence ◽

10.1016/j.jlumin.2019.04.043 ◽

2019 ◽

Vol 212 ◽

pp. 342-353 ◽

Cited By ~ 11

Author(s):

Ruby Priya ◽

O.P. Pandey

Keyword(s):

Alkali Metals ◽

Precipitation Method ◽

Co Precipitation ◽

Co Doped

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Near-Infrared-to-Green Upconversion in Yb3+/Er3+ Co-Doped BaYF5 by Chemical Co-Precipitation Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.663-665.328 ◽

2010 ◽

Vol 663-665 ◽

pp. 328-331 ◽

Cited By ~ 1

Author(s):

Hai Yan Du ◽

Wei Hang Zhang ◽

Jia Yue Sun

Keyword(s):

Optical Properties ◽

Laser Diode ◽

Near Infrared ◽

Precipitation Method ◽

Structural And Optical Properties ◽

Solution Processed ◽

Co Precipitation ◽

Barium Yttrium ◽

Co Doped

Barium yttrium fluorides ( BaYF5 ) co-doped with Er3+ and Yb3+ were synthesized by the chemical co-precipitation method and the structural and optical properties of solution-processed Er3+/Yb3+ co-doped BaYF5 were characterized. Intense visible emissions centered at around 523, 546 and 658 nm, originated from the transitions of 2H11/2 → 4I15/2, 4S3/2 → 4I15/2, and 4F9/2 → 4I15/2 of Er3+, respectively, have been observed in samples upon excitation with a 980nm laser diode, and the involved mechanisms have been explained.

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Synthesis and Luminescence Properties of Yb3+/Ho3+ Co-Doped Lu2O3 Nanocrystalline Powders

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.280-283.521 ◽

2007 ◽

Vol 280-283 ◽

pp. 521-524

Author(s):

Li Qiong An ◽

Jian Zhang ◽

Min Liu ◽

Sheng Wu Wang

Keyword(s):

Electron Microscopy ◽

Upconversion Luminescence ◽

Nanocrystalline Powders ◽

Precipitation Method ◽

X Ray Diffraction ◽

Excitation Spectra ◽

X Ray ◽

Transmission Electron ◽

Co Precipitation ◽

Co Doped

Yb3+ and Ho3+ co-doped Lu2O3 nanocrystalline powders were synthesized by a reversestrike co-precipitation method. The as-prepared powders were examined by the X-ray diffraction and transmission electron microscopy. The phase composition of the powders was cubic and the particle size was in the range of 30~50 nm. Emission and excitation spectra of the powders were measured by a spectrofluorometer and the possible upconversion luminescence mechanism was also discussed.

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Concentration-Dominated Temperature-Dependence of Upconversion Luminescence in Gd6WO12 Nanophosphor Co-Doped with Er3+ and Yb3+

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2016.12341 ◽

2016 ◽

Vol 16 (4) ◽

pp. 3534-3541

Author(s):

Yanqiu Zhang ◽

Baojiu Chen ◽

Xiangping Li ◽

Jiashi Sun ◽

Jinsu Zhang ◽

...

Keyword(s):

Upconversion Luminescence ◽

Thermal Quenching ◽

Precipitation Method ◽

X Ray Diffraction ◽

X Ray ◽

Two Photon ◽

Microscopic Morphology ◽

Co Precipitation ◽

Co Doped ◽

Scanning Electron

Nanosized Gd6WO12 phosphors containing various Er3+ concentrations and fixed Yb3+ concentration were synthesized by a co-precipitation method. The crystal structure and microscopic morphology of the obtained nanophosphors were characterized by means of X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). Two-photon processes for both the green and red upconversion (UC) emissions were confirmed by analyzing the dependence of UC intensities on 980 nm laser working current. UC emission intensity changing with temperature displays different trends for the samples with different Er3+ concentrations. The experimental results indicated that thermal quenching behavior of UC luminescence could not be simply explained by crossover mechanism. The enhancement for green UC emission in the sample with higher Er3+ concentration was discussed. Finally, the Er3+ concentration dependence of UC luminescence was experimentally observed, and its mechanisms were analyzed.

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Synthesis and characterization of Co-doped nano-TiO2 through co-precipitation method for photocatalytic activity

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-018-8910-x ◽

2018 ◽

Vol 29 (11) ◽

pp. 8914-8922 ◽

Cited By ~ 5

Author(s):

Mohamed Saber Lassoued ◽

Abdelmajid Lassoued ◽

Salah Ammar ◽

Abdellatif Gadri ◽

Abdelhamid Ben Salah ◽

...

Keyword(s):

Photocatalytic Activity ◽

Precipitation Method ◽

Synthesis And Characterization ◽

Nano Tio2 ◽

Co Precipitation ◽

Co Doped

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Preparation and tunable luminescence of CaCO3:Eu3+,Dy3+ phosphors

Functional Materials Letters ◽

10.1142/s1793604714500386 ◽

2014 ◽

Vol 07 (04) ◽

pp. 1450038 ◽

Cited By ~ 6

Author(s):

Yanwei Dong ◽

Ming Kang ◽

Ping Zhang ◽

Qijun Cheng ◽

Jie Wang

Keyword(s):

Rare Earth ◽

Uv Light ◽

Host Lattice ◽

Rare Earth Ions ◽

Precipitation Method ◽

Scanning Calorimetry ◽

Chromaticity Coordinates ◽

Co Precipitation ◽

Co Doped ◽

The Rare Earth

Phosphors based on calcium carbonate, co-doped with various Eu 3+ and Dy 3+ concentrations were prepared by microwave co-precipitation method. The prepared phosphors were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), thermogravimetry and differential scanning calorimetry (TG-DSC) and photoluminescence and photoluminescence excitation (PL-PLE) spectroscopy. Results showed that Dy 3+ and Eu 3+ ions were uniformly introduced into the host lattice of CaCO 3 taking the place of Ca 2+ ions. Under the excitation at 382 nm, the emission peak wavelengths were at 487 nm (4 F 9/2 → 6 H 15/2 of Dy 3+), 576 nm (4 F 9/2 → 6 H 13/2 of Dy 3+), and 614 nm (5 D 0 → 7 F 2 of Eu 3+). The luminescent intensities and emitting colors of Eu 3+- Dy 3+ co-doped CaCO 3 phosphors could be controlled by UV–violet excitations wavelengths or the rare-earth ions concentrations of Eu 3+ and Dy 3+ in phosphors. The chromaticity coordinates and photographs of samples under UV light showed the changes of the luminescence color intuitively through the varing UV–violet excitations wavelengths or the rare-earth ions concentrations of Eu 3+ and Dy 3+.

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