Vesna Đorđević

Vesna Đorđević
Vinča Institute of Nuclear Sciences | VIN · Department of Radiation Chemistry and Physics

PhD

About

66
Publications
11,914
Reads
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950
Citations
Additional affiliations
May 2019 - present
Vinča Institute of Nuclear Sciences
Position
  • Professor (Associate)
April 2015 - November 2016
Vinča Institute of Nuclear Sciences
Position
  • Research Associate
April 2015 - May 2019
Vinča Institute of Nuclear Sciences
Position
  • Professor
Education
October 2007 - June 2014
University of Belgrade
Field of study
  • Physical Chemistry

Publications

Publications (66)
Article
Full-text available
The near-infrared luminescence of Ca6Ba(PO4)4O:Mn5+ is demonstrated and explained. When excited into the broad and strong absorption band that spans the 500–1000 nm spectral range, this phosphor provides an ultranarrow (FWHM = 5 nm) emission centered at 1140 nm that originates from a spin-forbidden 1E → 3A2 transition with a 37.5% internal quantum...
Article
Full-text available
Eu3+-doped YxLu1−xNbO4 (x = 0, 0.25, 0.5, 0.75, 1) were prepared by the solid-state reaction method. YNbO4:Eu3+ and LuNbO4:Eu3+ crystallize as beta-Fergusonite (SG no. 15) in 1–10 μm diameter particles. Photoluminescence emission spectra show a slight linear variation of emission energies and intensities with the solid-solution composition in terms...
Article
Potential of Eu³⁺, Mn⁴⁺ co-doped YAG for dual-activated luminescence intensity ratio thermometry is investigated. The samples were prepared by modified Pechini method and cubic structure confirmed by X-ray diffraction with average crystallite size of ∼ 20 nm. Scanning electron microscopy revealed different sized chunks composed of ellipsoidal-shape...
Article
This paper presents the Cr³⁺-activated Mg2TiO4 phosphor temperature dependance of its near infrared luminescence and its potential in the optical thermometry applications. In this respect, temperature dependences of three emission features were tested over the broad temperature range (10–500 K): (i) the luminescence intensity ratio (LIR) between em...
Article
The multiparametric luminescence thermometry with Dy³⁺, Cr³⁺ double activated yttrium aluminium garnet – YAG is demonstrated. Phospors were synthesized via Pechini method and their structure is confirmed by X-ray diffraction analysis. Mean crystallite size of powders was calculated to be ~22 nm. Morphology was investigated using scanning electron m...
Article
Cr ³⁺ -doped Mg 2 SiO 4 orthorhombic nanoparticles are synthesized by a combustion method. The 3d ³ electron configuration of the Cr ³⁺ ion results in the deep-red emission from optical transitions between d–d orbitals. Two overlapping emissions from the Cr ³⁺ spin-forbidden ² E g → ⁴ A 2g and the spin-allowed ⁴ T 2g → ⁴ A 2g electronic transitions...
Article
This work demonstrates the luminescence of Mn4+ activated cubic spinel Li4Ti5O12 (LTO) powders. One-step solid-state method was used to obtain eleven samples with different quantities of Mn4+. The deep red emission centered at around 696 nm originates from 2Eg → 4A2g spin forbidden electronic transitions from 3 d3 electron configuration of Mn4+ ion...
Article
Full-text available
A promising way to improve the performance of luminescent materials is to combine them with noble metal nanoparticles. Herein, a set of silver/europium-doped lanthanum orthophosphate (Ag/La 0.95 Eu 0.05 PO 4) nanostructures with different concentrations of silver nanoparticles were prepared and investigated. The presented overlap between the strong...
Article
When activated by Dy3+, Na0.25K0.25Bi0.50TiO3 (NKBT), piezoelectric powders show strong luminescence in the blue and yellow spectral range. Emissions of this material can be effectively utilized for both luminescence intensity ratio and lifetime-based readouts of temperature. Photoluminescence measurements over a temperature range of 293–483 K show...
Article
Full-text available
The emission of Er 3+ provides three combinations of emission bands suitable for ratiometric luminescence thermometry. Two combinations utilize ratios of visible emissions (2 H 11/2 → 4 I 15/2 at 523 nm/ 4 S 3/2 → 4 I 15/2 at 542 nm and 4 F 7/2 → 4 I 15/2 at 485 nm/ 4 S 3/2 → 4 I 15/2 at 545 nm), while emissions from the third combination are locat...
Article
Full-text available
Ratiometric luminescence thermometry employing luminescence within the biological transparency windows provides high potential for biothermal imaging. Nd3+ is a promising candidate for that purpose due to its intense radiative transitions within biological windows (BWs) I and II and the simultaneous efficient excitability within BW I. This makes Nd...
Article
Surface modification of CeO2 nano-powder, synthesized by a self-propagating room temperature method with salicylate-type ligands (salicylic acid and 5-aminosalicylic acid) as well as catecholate-type ligands (catechol, 3,4-dihydroxybenzoic acid, caffeic acid and 2,3-dihydroxy naphthalene), induces the appearance of absorption in the visible spectra...
Article
In this work, the potential of Li1.8Na0.2TiO3:Mn4+ for the lifetime-based luminescence thermometry is assessed. The material is prepared by the solid-state reaction of Li2CO3, Na2CO3, and nanostructured TiO2 at 800 °C, and its monoclinic structure (space group C2/c) is confirmed by X-ray diffraction analysis. In this host, Mn4+ provides strong abso...
Article
Luminescence of monoclinic lithium metatitanate (Li2TiO3) powders activated with different quantities of Mn4+ is studied in detail. Its strong deep‐red emission arising from the Mn4+ 2Eg → 4A2g spin forbidden transition is centered at around 688 nm and is suitable for luminescence thermometry. Structural and electron paramagnetic resonance analyses...
Article
One of prospective ways for boosting efficiency of luminescent materials is their combination with noble metal nanoparticles. Collective, so-called plasmon, oscillations of surface electrons in nanoparticle can resonantly interact with incident or fluorescent light and cause increase in light absorption cross section or radiative rate for adjacent...
Article
YPO4 phosphors doped with trivalent ion Pr³⁺ were prepared by sol–gel method and treated with different doses of gamma radiation, from 0.25 MGy to 4 MGy. Effects of radiation on morphology, structure and luminescent properties were analyzed. Also, the influence of radiation on the change in the color of the samples was examined. The color efficienc...
Article
The binary luminescence thermometry probe is prepared from Y2O3:Ho3+ and Mg2TiO4:Mn4+ powders. This probe facilitates self‐referencing temperature readouts with excellent repeatability from both emission intensity ratio and excited state lifetimes. The ratio of intensities of Mn4+ deep red emission from 2E, 4T2→4A2 electronic transitions, and Ho3+...
Article
Surface modification of Al2O3 powders, prepared using reproducible sol-gel synthetic route with small colorless organic molecules, induces charge transfer complex formation and the appearance of absorption in the visible spectral region. Comprehensive microstructural characterization involving transmission electron microscopy, X-ray diffraction ana...
Article
Full-text available
MgTiO3 nanoparticles doped with Mn⁴⁺, with homogeneous size ranging about 63.1 ± 9.8 nm, were synthesized by a molten salt assisted sol gel method. These nanoparticles have been investigated as optical thermal sensors. The luminescence of tetravalent manganese ion in octahedral environment within the perovskite host presents drastic variations with...
Article
Dy³⁺-and Nd³⁺-doped YNbO4 powders were prepared using a mechanochemical method followed by annealing, and their photoluminescent properties were examined to assess the possibility of their use in phosphor thermometry. Luminescence intensity ratio technique was used as a temperature read-out scheme for both YNbO4:Dy³⁺ and YNbO4:Nd³⁺ samples. The cry...
Poster
Full-text available
In order to increase the efficiency of the absorption of solar radiation and the stability of the material we created an anatase nanopowder of appropriate geometry and changed the chemical structure of TiO2 by adding atoms of the rare earth metal neodymium.
Article
Under normal conditions, titanium dioxide does not absorb visible light photons due to large band gap. Nevertheless, when titanium dioxide nanoparticles (TiO2 NPs) are surface-modified with thiosalicylic acid (TSA), their optical properties are altered owing to the formation of charge transfer complex that initiates absorption in the visible spectr...
Article
Detailed study of Al2O3, an insulator with the band gap of about 8.7 eV, and its different organic/inorganic charge transfer complexes with visible-light photo activity is presented. In particular, prepared Al2O3 particles of the size 0.1 to 0.3 μm are coated with several organic complexes – the specific details for catecholate- and salicylate-type...
Article
The charge transfer complex formation between TiO2 powder and variety of phenol derivatives (phenol, 4-nitrophenol, 4-bromophenol, 4-tert-butylphenol, hydroquinone) was achieved. The red-shift of optical absorption was observed upon surface modification of TiO2 powders with phenol derivatives. The influence of substituent functional groups in para...
Chapter
Full-text available
Titanium dioxide is a wide band‐gap semiconductor of high chemical stability, nontoxicity and large refractive index. Because of the high photocatalytic activity, anatase is a preferred TiO 2 form in many applications such as for air and water splitting and purification. Doping of TiO 2 with various ions can increase the photocatalytic activity by...
Article
Sol-gel technique for the synthesis of anatase TiO2 at 420 °C produces nanocrystals of 10–20 nm in size with Ti4+ in crystal volume and Ti3+ at terminal planes of the crystal. The study of Li+ co-doping effects on the structure, morphology, absorption, and luminescence of Eu3+ activated TiO2 anatase nanocrystals is presented. Pure anatase structure...
Article
Full-text available
The rod-like Ag2CO3 particles (2-4 × 0.3-0.6 μm, length × diameter) were synthesized in water by the precipitation reaction between AgNO3 and NaHCO3 in the presence of polyvinylpyrrolidone. The X-ray diffraction analysis revealed the co-existence of monoclinic and hexagonal phases of Ag2CO3, without presence of impurities. The band gap energy of Ag...
Article
Herein, the synthesis, structural and crystal field analysis and optical spectroscopy of Mn4+ doped metal titanates ATiO3 (A = Ca, Mg) are presented. Materials of desired phase were prepared by molten salt assisted sol-gel method in the powder form. Crystallographic data of samples were obtained by refinement of X-ray diffraction measurements. From...
Article
The synthesized rod-like Ag2CO3 particles (2–4 × 0.3–0.6 μm, length × diameter) served as a precursor for preparation of the AgX/Ag2CO3 (X = Cl, I) composites by ion exchange method. The various microstructural (X-ray diffraction analysis, transmission electron microscopy, nitrogen adsorption-desorption isotherms) and optical (diffuse reflection sp...
Article
Here we report the synthesis and structural, morphological, and photoluminescence analysis of white‐ and blue‐light‐emitting Dy3+‐ and Tm3+‐doped Gd2Ti2O7 nanophosphors. Single‐phase cubic Gd2Ti2O7 nanopowders consist of compact, dense aggregates of nanoparticles with an average size of ~25 nm for Dy3+‐doped and ~50 nm for Tm3+‐doped samples. The p...
Article
Abstract Europium (III)-doped (YxSc1−x)2O3 nanocrystalline powders of different compositions (x =0, 0.25, 0.5, 0.75 and 1) are synthesized using a polymer complex solution method. Comparative structural and optical characterization is carried out with powder X-ray diffraction and photoluminescence excitation, emission and emission decay measurement...
Conference Paper
Full-text available
Ultraviolet photons generated by a KrF*-laser source (λ=248 nm) were used for the fabrication by Pulsed Laser Deposition (PLD) of nanometric Y2O3 and Y1.94Yb0.05Er0.01O3 thin films with controlled thickness, stoichiometry and photoluminescence properties. The expulsed material was collected onto SiO2 and Si (100) wafers. We studied the effects of s...
Article
This paper demonstrates the effects of Li+ co-doping on the structure, morphology, and luminescence properties of GdVO4:Er3+/Yb3+ phosphor prepared using a high-temperature solid-state chemistry method. The GdVO4:Er3+/Yb3+ powders synthesized with the Li+ co-dopant (in concentrations of 0,5, 10, and 15mol%) are characterized by X-ray powder diffrac...
Article
Nanocrystals of Y2O3 and La2O3 solid solutions were synthesized with a cubic bixbyite structure containing La2O3 content of up to 50 mol %. This is comparatively higher than in bulk materials of the same structure, where La2O3 content of only 20 mol % can be obtained. A set of europium-doped (Y1-xLax)2O3 (x=0.1, 0.2, 0.3, 0.4) cubic bixbyite solid...
Article
Full-text available
Yttrium aluminum garnet doped with rare earth ions (Ce3+, Eu3+ and Sm3+) was prepared by modified glycine method. Ce3+ as a dopant was used in four different concentrations (Y3-xCexAl5O12; x(%) = 1, 2, 3, 5), while doping concentration of Eu3+ and Sm3+ was Y3-xEuxAl5O12; x(%) = 3 and Y3-xSmxAl5O12; x(%) = 1, respectively. Phase composition of powde...
Article
Full-text available
This work explores the influence of dopant concentration on photoluminescent emission and kinetics of Eu3+-doped (0.2−10 at.%) nanocrystalline lanthanumoxide powders. The X-ray diffraction analysis confirmed that all samples crystallize in La2O3 hexagonal phase with space group P3¯ m1. Transmission electron microscopy showed particles with non-unif...
Article
Full-text available
Rare earth (RE) oxides are important hosts for the luminescence of RE activators with numerous practical applications in light-emitting devices. In this work, we investigated the possibility for Gd2O3:Eu3+ usage in phosphor thermometry by observing the temperature changes of trivalent europium ion transitions from the 5D0 and 5D1 energy levels to t...
Article
Eu3+-doped La2O3 nanocrystalline powder was prepared by polymer complex solution method and further used for preparation of Eu3+-doped La(OH)3. Structural and optical characterization was carried out by powder X-ray diffraction and photoluminescent spectroscopy. XRD measurements confirmed the formation of hexagonal La2O3 and its recrystallization i...
Article
Full-text available
In this report, structure, morphology and luminescence of Y2O3:Sm3+ nanoparticles prepared by self-propagating room temperature reaction are presented. This new, simple and cost effective synthesis allows obtaining desired phase composition by mixing appropriate amounts of yttrium and samarium nitrates together with sodium hydroxide. A set of sampl...
Article
Gadolinium-oxide nanopowders doped with Yb3+ and Ho3+ ions and co-doped with alkali metal ions (Li+ and Na+) were synthesized via polymer complex solution method and their up-conversion emission properties are analyzed. Prepared powders were well crystallized in cubic bixbyite structure, without any impurity phases and with an average crystallite s...
Article
Full-text available
New red sesquioxide phosphor, Eu3+-doped (Y0.5La0.5)2O3, was synthesized in the form of nanocrystalline powder with excellent structural ordering in cubic bixbyite-type, and with nanoparticle sizes ranging between 10 and 20 nm. Photoluminescence measurements show strong, Eu3+ characteristic, red emission (x = 0.66 and y = 0.34 CIE color coordinates...
Article
Full-text available
In this paper we demonstrate visible up-conversion emission of Er3+ doped (Lu0.5Y0.5)2O3 nanophosphor and discuss possible mechanisms for pumping the upper energy levels of Er3+ ions. Polymer complex solution synthesis yields well crystalline, pure-phase cubic nanopowder with particle size in the 20–50nm range. Red, green and blue up-conversion emi...
Article
Full-text available
Rare-earth orthovanadates are important hosts for the luminescence of rare earth activators with considerable practical applications in the artificial production of light. In this paper we investigated the possibility for GdVO4:Sm3+ usage in phosphor thermometry by observing the temperature changes of trivalent samarium transitions from 4F3/2 and 4...
Conference Paper
Samarium doped LaYO3 nanocrystalline phosphor powders are obtained by polymer complex solution method. Stoichiometric quantities of La2O3, Y2O3 and for dopant ions Sm2O3 were dissolved in hot nitric acid. Polyethylene glycol was added in solutions in 1:1 mass ratio to corresponding metal nitrates to form gel. The gel is combusted and annealed at 80...
Article
Full-text available
The present study shows simultaneous surface ionisation and electron impact ionisation during the formation and investigation of endohedral fullerenes 99mTc@C60 and 99mTc@C70. The endohedral fullerenes were generated using a mass spectrometer with a triple rhenium filament as an ion source. The ionisation energies (IE) determined were: 8.52 ± 0.25...
Article
Full-text available
In the present work we explored the possibility of obtaining Y2O3:Eu3+ mu m-size particles by an ultrasonic spray pyrolysis method. As-prepared sample constitutes of spherical, hollow particles with an average size of 1 to 2 mu m. Pure, well crystalline, cubic Y2O3 is formed after additional thermal treatment at 800 degrees C for 2 h. A detailed op...
Article
Full-text available
Ionization energies of non-stoichiometric Li n F nÀ1 (n ¼ 3, 4, 6) clusters determined by a thermal ionization mass spectrometry (TIMS) were 4.2 AE 0.2 eV for Li 3 F 2 , 4.3 AE 0.2 eV for Li 4 F 3 and 4.1 AE 0.2 eV for Li 6 F 5. The ionization energy of Li 6 F 5 cluster was obtained experimentally for the first time. The ionization energies of Li 3...
Article
Full-text available
Ionization energies of non-stoichiometric LinFn−1 (n = 3, 4, 6) clusters determined by a thermal ionization mass spectrometry (TIMS) were 4.2 ± 0.2 eV for Li3F2, 4.3 ± 0.2 eV for Li4F3 and 4.1 ± 0.2 eV for Li6F5. The ionization energy of Li6F5 cluster was obtained experimentally for the first time. The ionization energies of Li3F2 and Li4F3 are in...
Article
Full-text available
Using the ion implantation technique (introducing negatively charged fullerene into a low temperature lithium plasma column by a strong axial magnetic field) endohedral fullerenes Li@C70, Li2@C 70 and Li3@C70 were produced. Mass spectral studies (both TIMS-thermal ionization mass spectrometry and MALDI TOF MS - matrix assisted laser desorption ioni...
Article
Full-text available
Hypervalent molecules of Li3F and Li4F were detected experimentally for the first time. Ionization energies determined by the thermal ionization mass spectrometry were 3.8 ± 0.2 eV for Li2F, 4.0 ± 0.2 eV for Li3F and 3.9 ± 0.2 eV for Li4F. The ionization energies obtained by ab initio calculations support the experimental findings. The lowest energ...
Article
Full-text available
Molecules of Li(n)X (n = 2, 3; X = Cl, Br, I) were examined with a magnetic sector mass spectrometer by surface ionization using a triple rhenium filament impregnated with fullerene (C60). The ionization energies obtained for Li(2)Cl, Li(2)Br and Li(2)I molecules are 3.8 +/- 0.1, 3.9 +/- 0.1 and 4.0 +/- 0.1 eV, respectively. The first ionization en...
Article
Full-text available
In this work we have studied the Li/C60, Li/C70, 99mTc/C60, 99mTc/C70, Gd/C 60, Gd/C70, Nd/C60, Nd/C70, Y/C 60 and Y/C70 systems by surface ionization mass spectrometry and investigated a possibility of the formation of endohedral fullerenes. Using the ion implantation technique (introducing negatively charged fullerene into a low temperature lithi...
Article
In an attempt to purify MWNT in mild conditions, we have applied two different methods of purification. The first method of purifying the material was a combination of relatively often used methods, such as etching and acid treatment, and the second method was a relatively new one, using an organic polymer PmPV. Sample purity was obtained with SEM...