Production and characterization of magnetic and luminescent Gd2O2SO4:Eu3+ nanoparticles by sol-gel technique (original) (raw)
Related papers
Acta Physica Polonica A, 2017
Scintillation materials are widely used in digital X-ray imaging applications, radiotherapy applications coupled with suitable photoreceptors. Gd2O2SO4 (GOS) scintillator doped with trivalent praseodymium (Pr 3+) presented high X-ray absorption properties and good spectral compatibility which were utilized extensively for imaging system of X-ray microscopy, soft X-ray phosphor screen for water window. In this study, GOS:0.01Pr 3+ scintillation material was synthesized by unique sol-gel process which was not previously applied and its characterization properties were investigated. Structure and luminescence properties of GOS:Pr 3+ were optimized by utilizing X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and luminescence spectroscopy.
Journal of Materials Engineering and Performance, 2018
A facile direct precipitation method was used for the synthesis of luminescence nanomaterial. Gd 2 O 3 doped with rare earth element Eu 3+ is synthesized by polyol route. The synthesized nanoparticles show their characteristic red emission. The nanoparticles are characterized by x-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and photoluminescence (PL) study. The synthesized nanoparticles are spherical particles with $ 30 nm size. The photoluminescence studies show the characteristic Eu 3+ red emission. The PL study shows the intensity of the magnetic dipole transition (5 D 0 ! 7 F 1) at 592 nm compared to that of the electronic dipole transition (5 D 0 ! 7 F 2) at 615 nm. The nanomaterials can show significant application in various display devices and biomedical applications for tracking.
Preparation, structure and luminescence properties of nanocrystalline Eu:Gd3Sc2Ga3O12
Journal of Alloys and Compounds, 2009
Eu:Gd 3 Sc 2 Ga 3 O 12 powder was synthesized by co-precipitation method with metal Ga, Eu 2 O 3 , Gd 2 O 3 , Sc 2 O 3 as starting materials and aqueous ammonia as precipitator. X-ray diffraction (XRD), the Rietveld refinement method and transmission electron microscope (TEM) were employed to study the crystal structure. The fluorescent spectra and decay curves were used to investigate the luminescence properties of the resulting powders. The XRD spectra and results of the Rietveld refinement indicated that the structure of Gd 3 Sc 2 Ga 3 O 12 hardly changed and only crystal lattice distorted a little when Eu 3+ ion was doped. The transmission electron microscope (TEM) observation and XRD line broadening calculation revealed that the particle size of Eu:Gd 3 Sc 2 Ga 3 O 12 powder increased with the increase of the calcination temperature. At the same time, the emission intensity and lifetime of Eu:Gd 3 Sc 2 Ga 3 O 12 powder also increased with the calcination temperature. In the emission spectra, a 590 nm orange line from 5 D 0 → 7 F 1 as the most prominent group meaned that Eu 3+ ion mainly occupied the inversion center in Gd 3 Sc 2 Ga 3 O 12 crystal which may be caused by a small number of Gd atoms entered the 16(a) site.
Gd2O2S:Eu3+ Nanophosphors: Microwave Synthesis and X-ray Imaging Detector Application
Materials Research
Red-emitting Gd 2 O 2 S:Eu 3+ nanophosphors were successfully prepared using a microwave irradiation method followed by hydrogenation treatment. The optimum calcination temperature (900 °C) was determined by thermogravimetric-differential scanning calorimetry. The X-ray diffraction results showed that all the samples consisted of the pure hexagonal Gd 2 O 2 S:Eu 3+ phase. The field emission scanning electron microscopy images showed that the Gd 2 O 2 S:Eu 3+ nanophosphors were spherical, and their average particle diameter increased parallel with the microwave irradiation power. The photoluminescence spectra (under 325-nm excitation) of the samples exhibited red emission corresponding to the 5 D 0 → 7 F 2 transition of Eu 3+ ions. A Gd 2 O 2 S:Eu 3+ nanophosphor screen film was fabricated using the particlebinder sedimentation method. The result shows that the luminance of the Gd 2 O 2 S:Eu 3+ nanophosphor screen film increased with an increase in the X-ray energy. Hence, this film would become one of the potential candidate for future imaging applications.
Journal of Solid State Chemistry, 2003
The characterization and luminescence properties of nanostructured Gd 2 O 3 :Eu 3+ phosphors synthesized by a sol-lyophilization process are presented. After preparation of gadolinium-based sols from gadolinium nitrate and ammonium hydroxide, the soprepared sols were freeze dried at À101C and calcinated at different temperatures. For temperatures lower than 1300 K, highly crystalline samples with the cubic structure can be obtained without concomitant grain growth of the particles (o50 nm). The luminescence spectra contain all possible transitions of Eu 3+ with C 2 symmetry and present two major features: an increase of the luminescence efficiencies of the phosphors in comparison with that obtained by solid-state reaction and the presence of an additional peak at about 609 nm at the vicinity of the 5 D 0 -7 F 0y4 transition. r
Optik - International Journal for Light and Electron Optics, 2015
Er 3+ doped Y 2 O 3 novel phosphor was successfully synthesized by solid state reaction process using boric acid as a flux. The Structural characterization was done by using simple X-ray diffraction technique. The Morphological studies were done by scanning electron microscope and transmission electron microscope. From X-ray diffraction, it was observed Er 3+ doped Y 2 O 3 nanoparticles (NPs) have cubic structure and further crystallite sizes were calculated by Debye Sherrer's formula. The particle Size was found in the range of ≈70 nm confirmed by TEM result. The optical property of prepared phosphor was examined by Photoluminescence spectra. The emission spectra was recorded under 275nm excitation and found in the range 350-700 nm
Synthesis of Gd2O3:Eu nanoplatelets for MRI and fluorescence imaging
Nanoscale Research Letters, 2015
We synthesized Gd 2 O 3 and Gd 2 O 3 doped by europium (Eu) (2% to 10%) nanoplatelets using the polyol chemical method. The synthesized nanoplatelets were characterized by X-ray diffraction (XRD), FESEM, TEM, and EDX techniques. The optical properties of the synthesized nanoplatelets were investigated by photoluminescence spectroscopy. We also studied the magnetic resonance imaging (MRI) contrast enhancement of T1 relaxivity using 3 T MRI. The XRD for Gd 2 O 3 revealed a cubic crystalline structure. The XRD of Gd 2 O 3 :Eu 3+ nanoplatelets were highly consistent with Gd 2 O 3 indicating the total incorporation of the Eu 3+ ions in the Gd 2 O 3 matrix. The Eu doping of Gd 2 O 3 produced red luminescence around 612 nm corresponding to the radiative transitions from the Eu-excited state 5 D 0 to the 7 F 2 . The photoluminescence was maximal at 5% Eu doping concentration. The stimulated CIE chromaticity coordinates were also calculated. Judd-Ofelt analysis was used to obtain the radiative properties of the sample from the emission spectra. The MRI contrast enhancement due to Gd 2 O 3 was compared to DOTAREM commercial contrast agent at similar concentration of gadolinium oxide and provided similar contrast enhancement. The incorporation of Eu, however, decreased the MRI contrast due to replacement of gadolinium by Eu.
Nanoscale, 2014
We have synthesized gadolinium oxysulfide nanoparticles (NPs) doped with other lanthanides (Eu 3+ , Er 3+ , Yb 3+ ) via a hydroxycarbonate precursor precipitation route followed by a sulfuration process under a H 2 S-Ar atmosphere at 750 C in order to propose new multimodal nanoplatforms for Magnetic Resonance (MR), X-ray and photoluminescence imaging. Gd 2 O 2 S:Eu 3+ NPs strongly absorb near UV (z300-400 nm) and re-emit strong red light (624 nm). They can be easily internalized by cancer cells, and imaged by epifluorescence microscopy under excitation in the NUV (365 nm). They are not cytotoxic for living cells up to 100 mg mL À1 . Consequently, they are well adapted for in vitro imaging on cell cultures. Gd 2 O 2 S:Eu 3+ NPs also show strong transverse relaxivity and strong X-ray absorption allowing their use as contrast agents for T 2 -weighted MRI and X-ray tomography. Our study shows that Gd 2 O 2 S:Eu 3+ NPs are considerably better than commercial Ferumoxtran-10 NPs as negative contrast agents for MRI. Upconversion emission of Gd 2 O 2 S:Er; Yb (1; 8%) NPs under infrared excitation (l ex ¼ 980 nm) shows mainly red emission (z650-680 nm). Consequently, they are more specifically designed for in vivo deep fluorescence imaging, because both excitation and emission are located inside the "transparency window" of biological tissues (650-1200 nm). Magnetic relaxivity and X-ray absorption behaviors of Gd 2 O 2 S:Er; Yb NPs are almost similar to Gd 2 O 2 S:Eu 3+ NPs.
Radiation Measurements, 2004
This paper reports on the synthesis and characterization of Gd2O3:Eu 3+ nanocrystals of di erent sizes. The particles have been synthesized by a sol-lyophilization process. This methods allows the synthesis of 7-100 nm diameter cubic-phase particles. The photoluminescence properties have been studied with di erent excitation from X-ray to VUV and visible wavelengths. Compared to the properties of the bulk materials, some important changes on the luminescence are observed. In particular some bands are strengthened when the size of the particles is diminished. We could therefore ascribe this bands to doping ions on a site close to the surface. Also a very low e ciency of excitation for small particles is observed when exciting with X-ray or high-energy VUV photons (i.e. when exciting the host matrix) compared to the e ciency obtained when exciting in the charge transfer band or in the doping ions related states.