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1

Analysis of surface properties of semiconducting (Ti,Pd,Eu)Ox thin films

Wojcieszak D., Kaczmarek D., Domaradzki J.

Opto-Electronics Review

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2016

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Vol. 24, No. 1

15--19

EN

In this paper an analysis of the surface properties of (Ti,Pd,Eu)Ox thin films prepared by magnetron sputtering has been described. In particular, the results of composition and structure investigations were studied in relation to the surface state and optical properties. It was found that (Ti,Pd,Eu)Ox film was nanocrystalline and had a rutile structure. The average crystallites size was equal to 7.8 nm. Films were homogeneous and had densely packed grains. Investigation of the surface properties by XPS showed that titanium was present at 4+ state (in the TiO2 form), palladium occurred as PdO2 (also at 4+ state), while europium was in Eu2O3 form (at 3+ state). In comparison with the unmodiffied TiO2, the coating with Pd and Eu additives had a rather high transparency (approx. 47%) in the visible light range, its optical absorption edge was shifted towards into the longer wavelengths (from 345 nm to 452 nm), and the width of optical energy gap Egopt was nearly twice lower (1.82 eV). Besides, the resistivity of (Ti,Pd,Eu)Ox at room temperature was 1×103 Wcm. In the case of the film as-deposited on Si substrate (p-type) the generation of photocurrent as a response to light beam excitation (λexc = 527 nm) was observed.

2

Analysis of metal surfaces coated with europium-doped titanium dioxide by laser induced breakdown spectroscopy

Głogocka D., Noculak A., Pucińska J., Jopek W., Podbielska H., Langner M., Przybyło M.

Acta of Bioengineering and Biomechanics

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2015

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Vol. 17, no. 3

33--40

EN

The surface passivation with titanium sol-gel coatings is a frequently used technique to control the adsorption of selected biological macromolecules and to reduce the exposure of the bulk material to biological matter. Due to the increasing number of new coating-preparation methods and new gel compositions with various types of additives, the quality and homogeneity determination of the surface covering is a critical factor affecting performance of any implanted material. While coating thickness is easy to determine, the homogeneity of the surface distribution of coating materials requires more elaborate methodologies. In the paper, the laser induced breakdown spectroscopy (LIBS) based method, capable to quantitate the homogeneity and uniformity of the europium in titanium dioxide sol-gel coatings on stainless steel surfaces prepared with two different procedures: spin-coating and dip-coating, is presented. The emission intensity of titanium has been used to determine the coating thickness whereas the relative values of europium and titanium emission intensities provide data on the coating homogeneity. The obtained results show that the spin-coating technique provides better surface coverage with titanium dioxide. However, when the surface coating compositions were compared the dip-coating technique was more reliable.

3

The Recovery of Yttrium and Europium Compounds from Waste Materials

Góralczyk S., Uzunow E.

Archives of Environmental Protection

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2013

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Vol. 39, no. 3

107--114

EN

Rare earth metals including yttrium and europium are one of several critical raw materials, the use of which ensures the development of the so-called high technology. The possibility of their recovery in Europe is limited practically only to secondary materials such as phosphogypsum and electronic waste. The article presents the results of our research concerning the development of recovery technology of yttrium and europium from luminophore CRT used lamps. It describes the principle of separation of elements and the test results of cleaning the concentrate. It was shown that the costs of preparing the concentrate according to the proposed technology are lower than the phosphogypsum processing technology and the composition of the resulting product does not contain hazardous substances.

PL

Metale ziem rzadkich, w tym itr i europ należą do tej grupy kilkunastu surowców krytycznych, których stosowanie zapewnia rozwój w obszarze tzw. wysokich technologii. Możliwość ich pozyskiwania w Europie ogranicza się praktycznie do surowców wtórnych, np. fosfogipsów oraz zużytego sprzętu elektronicznego. W artykule przedstawiono wyniki badań autorów dot. opracowania technologii odzysku itru i europu z luminoforu zużytych lamp kineskopowych. Opisano zasady wydzielania pierwiastków i wyniki badań oczyszczania koncentratu. Wykazano, że koszty otrzymywania koncentratu wg proponowanej technologii są niższe od technologii przeróbki fosfogipsów, a otrzymany produkt nie zawiera substancji niebezpiecznych.

4

Sorption and migration of Cs, Sr, and Eu in gypsum - groundwater system

Alhassanieh O., Mrad O., Ajji Z.

Nukleonika

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2012

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Vol. 57, No. 1

125-131

EN

The distribution of 137Cs, 152Eu, and 85Sr in a solid/aqueous system, gypsum in contact with groundwater, was investigated using gamma-spectrometry. The sorption and migration of the radionuclides were investigated. The aqueous phase was characterized using instrumental neutron activation analysis (INAA) and high performance liquid chromatography (HPLC). The solid phases were characterized using X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The investigations included three kinds of gypsum: mineral, commercial, and own prepared gypsum. The influence of some parameters on sorption/migration of the radionuclides were studied, such as contact time, pH, and concentrations of concurrent elements. The effect of element concentration was also investigated. The results show the ability of gypsum to keep Sr and Eu in the solid phase in all three cases. The incorporation of Cs in the solid phase depends on the conditions and used materials, and varies between 93 and 97%.

5

Migration of strontium, cesium, europium and uranium from poly(methyl styrene)- and polystyrene - phosphate composites prepared using gamma radiation

Alhassanieh O., Ajji Z.

Nukleonika

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2012

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Vol. 57, No. 3

369-374

EN

Composites consisting of natural phosphate powder and two monomers (styrene or methyl styrene) have been prepared by means of gamma irradiation. The polymerization reaction was followed up using a thermogravimetric analyzer (TGA) to determine the conversion of the polymerization. Differential scanning calorimeter (DSC) was used to locate and determine the glass transition temperature (Tg) of the prepared samples. The distribution of 137Cs, 152Eu, 85Sr and 238U in a solid-aqueous system, composites of phosphate-poly(methyl styrene) and of phosphate-polystyrene in contact with groundwater, was investigated using alfa-spectrometry and fluorometry. The effects of contact time, pH, and the concentration of concurrent element (Ca) were studied. The results were compared with earlier results with phosphate alone in the solid phase. The ability of the produced composites to keep the studied radioisotopes in the solid phase is much higher than in the mineral phosphate. This improvement is more remarkable for strontium and cesium than for europium and uranium, due to their high element ratio in the solid phase in phosphate experiments.

6

Influence of sol-gel matrices on the optical excitation of europium ions

Banski M., Podhorodecki A., Misiewicz J.

Materials Science Poland

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2010

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Vol. 28, No. 1

217--227

EN

Photoluminescence (PL), total photoluminescence excitation (TPLE), transmission and decay photoluminescence experiments were done to establish the most efficient excitation mechanism of the europium (Eu3+) ions in amorphous Al2O3 and Y3Al5O12 host matrices. Both matrices were fabricated using the sol-gel technique, doped with Eu3+ ions and sputtered on a flat quartz plate. Because of relatively low temperatures of annealing (200 °C), after this treatment the matrices should remain in an amorphous phase. In such a system, Eu3+ ions occupy the points having different site symmetries. However, based on characteristic features of the PL spectra, the effective site symmetry (ESS) parameter was defined to describe the PL properties of the Eu3+ ions in various matrices. Low intensive direct f-f transitions at 392, 465, 530 nm were observed in the TPLE spectra. The most intensive, wide excitation bands were centred at around 250-260 nm and the charge transfer process was found to be related to these excitation bands. Finally, a good correlation between photoluminescence lifetimes, the PL intensity and CT energy was observed.

7

Influence of post annealing on optical and structural properties of Eu and Pd-doped TiO2 thin films

Domaradzki J., Borkowska A., Kaczmarek D., Podhorodecki A., Misiewicz J.

Optica Applicata

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2007

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Vol. 37, nr 1-2

51-56

EN

This work presents optical and structural characterization of europium and palladium doped titanium dioxide thin films prepared by modified magnetron sputtering. The metallic Eu and Pd dopants have been co-sputtered from a base Ti target (mosaic target) and deposited on SiO2 substrates. After the deposition samples were additionally annealed in air ambient for 2 hours at the temperatures of 200 °C, 400 °C, 600 °C and 800 °C, respectively. Structural properties of TiO2:(Eu, Pd) thin films were examined using X-ray diffraction (XRD). XRD patterns recorded after thermal treatment showed the dominating TiO2-rutile phase, independently of the temperature of annealing. Optical properties were studied as defined by optical transmission. It has been shown, that doping shifts the fundamental absorption edge of TiO2 toward the longer wavelength range. As the samples were additionally annealed the band gap widening has been observed from 1.7 eV, for as deposited sample up to 2.31 eV for those annealed at 800 °C.

8

Influence of Eu dopant on optical properties of TiO2 thin films fabricated by low pressure hot target reactive sputtering

Borkowska A., Domaradzki J., Kaczmarek D.

Optica Applicata

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2007

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Vol. 37, nr 1-2

117-122

EN

This work presents the influence of europium dopant on optical properties of TiO2:Eu3+ thin films fabricated by low pressure hot target reactive sputtering. Thin films were deposited from metallic Ti-Eu mosaic target on different substrates (i.e., monocrystalline silicon and SiO2). Selected samples were additionally annealed for 4 hours in an air ambient at 200 °C after deposition. Thin films were examined by means of scanning electron microscopy with energy disperse spectrometer (SEM-EDS), X-ray diffraction (XRD), optical transmission method and photoluminescence (PL). From SEM-EDS measurements total Eu concentration in fabricated thin films was determined. XRD analysis revealed the existence of crystalline TiO2 in the form of anatase and rutile in examined samples with smaller and larger amount of Eu dopant, respectively. Optical transmission method showed that doping with selected amount of Eu results in different shift of the fundamental absorption edge for prepared thin films. PL studies showed a red luminescence of TiO2:Eu3+ thin films. The intensity of luminescence increased with the annealing temperature and decreased with larger amount of europium.

9

FAAS determination of selected rare earth elements coupled with multielement solid phase extractive preconcentration

Biju V. M., Rao T.P.

Chemia Analityczna

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2005

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Vol. 50, No. 5

935-944

EN

Preparation of 5,7-dichloroquinolinc-8-ol functional!zed naphthalene, a solid reagent for quantitative preconcentration of Nd, Eu and Lu from diluted aqueous and synthetic seawa-tcr solutions in the pH range of 8.0 š 0.2 has been described. Solid mixture enriched with the analyzed metal ion and containing the solid phase cxtractant was dissolved in 5 mL of DMF. After that, the Rare Earth Element (REE) content was established by Flame Atomic Absorption Spectrometry. Calibration plots were rectilinear over the ranges 0-1 800, 0-150 and 0-1300 μ.g of Nd, Eu and Lu, respectively present in 1.0 L of the aqueous solution. Five replicate determinations of 100 μg of Nd, Eu or Lu present in 1.0 L of the sample solution were performed. Average absorbance values equalled to 0.013, 0.13 and 0.015, respectively. The corresponding relative standard deviations were: 2.5, 1.8 and 2.4%. Detection limits (expressed as 3 times the standard deviation of a blank) and enrichment factors were found to be 40μ L-1 and 200, 4.0 ug L-1 and 200, and 30 μg L-1 and 200 for Nd. Eu and Lu, respectively. Nd, Eu and Lu contents in scawater could be quantified by ICP-MS after prior preconcentration of the analytes applying the proposed procedure.

PL

Opisano preparatykę stałego odczynnika do wstępnego zatężania Nd, Eu i Lu z rozcieńczonych roztworów wodnych lub syntetycznej wody morskiej w zakresie pH: 8 š 0.2, którym jest jednorodna mieszanina naftalenu z 5,7-dichloro-8-hydroksy-chinoliną. Odczynnik wzbogacony zatrzymanymi jonami metali rozpuszczano w 5 mLDMF i oznaczano pierwiastki ziem rzadkich (REE) za pomocą płomieniowej atomowej spektrometrii absorpcyjnej. Krzywe kalibracyjne były prostoliniowe w zakresach stężeń: 0-1800, 0-150, 0-1300 &mu.g w l L roztworu. Średnie wartości absorbancji wynosiły odpowiednio: 0.013, 0.13 i 0.015 a odpowiadające im odchylenia standardowe: 2,5, 1,8 i 2.4%. Granice wykrywalności (określone jako trzykrotna wartość odchylenia standardowego ślepej próby) wynosiły odpowiednio: 40, 4,0 i 30 μg L-1 dla Nd, Eu i Lu. Współczynniki wzbogacenia wynosiły 200 dla wszystkich trzech pierwiastków Nd, Eu i Lu. Opracowaną metodę wstępnego zateżania REE w połączeniu z ICP-MS zastosowano także do oznaczania tych pierwiastków w wodzie morskiej.

10

Adsorption of strontium, europium and americium(III) ions on a novel adsorbent Apatite II

Krejzler J., Narbutt J.

Nukleonika

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2003

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Vol. 48, nr 4

171-175

EN

A novel material, Apatite II, obtained from a natural source, has been determined to be a good adsorbent for radionuclides of strontium, europium and trivalent actinides, but not caesium, from neutral aqueous solutions containing common chelating agents and inorganic salts at moderate concentrations. This inexpensive, easily available material seems to be a promising backfill for engineered barriers in nuclear waste repositories. However, encapsulation of the sorbent grains loaded with radiostrontium in the Portland cement matrix results in undesirably high leaching rate for this particular radionuclide.

11

Structure, spectroscopy and dielectric properties of BaTiO3:Eu3+ nanocrystallites prepared by the sol-gel method

Hreniak D., Łukowiak E., Maruszewski K., Pązik R., Stręk W.

Materials Science

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2002

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Vol. 20, No. 1

43-50

EN

Eu3+-doped BaTiO3 nanocrystalline powders have been obtained by sol-gel method. Their morphology, structure and dielectric properties have been investigated as a function of sintering temperature. The powders sintered at the temperatures below 800 st.C demonstrate luminescence behaviour characteristic of the inversed symmetry Eu3+ sites, where only the 5D0 ??7F1 transitions are allowed. Above this temperature the system undergoes a phase transition characterized by lack of inversion symmetry enabling the dipole-electric transitions.

12

Solvent extraction of inorganic and organic cations by octakis-O-diphenoxyphosphoryl-tetramethylcalix[4]resorcinarene

Taraszewska J., Koźbiał M.

Chemia Analityczna

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2002

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Vol. 47, No. 3

409-418

EN

Extraction of alkali metal, alkaline-earth metal Mg(II), Ca(II) cations and ammonium picra-tes as well as of Eu(IIl) and La(IlI) nitrates by complexation with octakis-O-diphenoxyphos-phoryl-tetramethylcalix[4] resorcinarene was studied by a liquid-liquid extraction from aqueous phase into chloroform. Extraction percentages (E%), stoichiometry and overall extraction constants (Kex) were determined. E% increased in the order lanthanum, europium >alka-line earth cations >ammonium cations>alkali cations. The stoichiometry of the complexes was 1:1. Kex increased with the increase of cation charge.

PL

Zbadano ekstrakcję z fazy wodnej pikrynianów metali alkalicznych, ziem alkalicznych Mg(II), Ca(II) i alkiloammoniowych oraz azotanów Eu(III) i La(lII) w wyniku komplekso-wania roztworem oktakis- difenoksyfosforylo-tetrametylokaliks[4]rezorcynarenu w chloroformie. Wyznaczono procenty ekstrakcj i (E%), stechiometrie, i stale ekstrakcj i (Kex). E% wzrastał w kolejności, lantan, europ >kationy metali ziem alkalicznych >kationy alkiloamo-niowe >kationy metali alkalicznych. Stechiometria kompleksów była1: 1. Kex wzrastała ze wzrostem ładunku kationu

13

Parametry spektroskopowe szkieł fluoroindowych domieszkowanych jonami europu

Pisarska J.

Archiwum Nauki o Materiałach

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2001

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T. 22, nr 3

203-214

PL

W artykule zaprezentowano właściwości spektroskopowe szkieł fluoroindowych domieszkowanych jonami europu. Na podstawie widm absorpcyjnych i emisyjnych wyznaczono charakterystyczne wielkości spektroskopowe badanych szkieł: parametry wiązania (beta i delta), parametry intensywności przejść Omega t, efektywne szerokości spektralne pasm emisyjnych delta nu eff, zmierzone i obliczone czasy życia tau, współczynniki rozgałęzienia luminescencji beta, współczynnik intensywności fluorescencji R, oraz wartości przekroju czynnego na emisję wymuszoną sigma em. Parametry spektroskopowe porównano z wartościami otrzymanymi dla szkieł fluorkowych i tlenkowych.

EN

Some spectroscopic properties of fluoroindate glasses doped with Eu3+ ions have been examined. From the absorption and emission spectra in the UV-VIS-NIR region, spectroscopic parameters such as bonding (beta and delta), Judd-Ofelt intensity parameters Omega t, effective linewidths delta nu eff, measured and calculated radiative lifetimes tau, branching ratios beta, fluorescence intensity ratio R and peak stimulated emission cross sections have been obtained and compared with similar results reported for fluoride and oxide glasses.

14

Badania reakcji dehydratacji kompleksów prazeodymu(III), neodymu(III), europu(III), gadolinu(III), dysprozu(III) i erbu(III) z kwasem kwercetyno-5'-sulfonowym

Kopacz M., Nowak D.

Zeszyty Naukowe Politechniki Rzeszowskiej. Chemia

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1999

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z. 16 [173]

45-49

PL

Przeprowadzono syntezę oraz badania derywatograficzne kompleksów jonów Pr(III), Nd(III), Eu(III), Gd(III), Dy(III), Er(III) z kwasem kwercetyno-5'sulfonowym i wyznaczono ich energię aktywacji (Ea) reakcji dehydratacji. Stwierdzono, że kompleksy prazeodymu, neodymu, gadolinu i erbu mają większe wartości energii aktywacji niż kompleksy europu i dysprozu.

EN

Thermogravimetric analysis complexes of Pr(III), Nd(III), Eu(III), Gd(III), Dy(III) and Er(III) ions with quercetin-5'-sulfonic acid were carried out. Activation energy (Ea) reaction of dehydration was appointed. It was stated, that complexes of praseodymium, neodymium, gadolinium and erbium had higher values of activation energy than complexes of europium and dysprosium.

15

Sorption of long-lived radionuclides from model liquid radioactive wastes on α-crystalline polyantimonic acid

Satyanarayana J., Bilewicz A., Narbutt J.

Nukleonika

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1998

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Vol. 43, nr 4

531-538

EN

A method was investigated for removal and immobilisation of hazardous long-lived radionuclides from liquid radioactive wastes containing macroamounts of other metal ions and complexing agents. Selective inorganic ion exchangers: α-crystalline polyantimonic acid (CAA) and metal antimonates were synthesized and studied as adsorbents for di- and trivalent ions: Sr(sup 2+) and Eu(sup 3+) (a model for actinides), and also monovalent Cs(sup +). High decontamination factors for the two former ions have been attained with CAA. The effect of the concentration of the waste components on the radionuclide sorption was studied. Calcium ions strongly reduce sorption of Sr(sup 2+), and EDTA in neutral solution - that of Eu(sup 3+), while sodium ions, citrates and oxalates have a little effect. Radiocaesium must be removed using another selective ion exchanger.

PL

Badano możliwości usuwania i związania w fazie stałej toksycznych radionuklidów długożyciowych z ciekłych odpadów promieniotwórczych zawierających makroilości jonów innych metali i związków chelatujących. Zsyntezowano selektywne nieorganiczne wymieniapze jonów: α-krystaliczny kwas poliantymonowy (CAA) i antymoniany metali wielowartościowych oraz zbadano ich własności sorpcyjne względem dwu- i trójwartościowych jonów strontu i europu (jako modelu aktynowców), a także jednowartościowego cezu. CAA okazał się bardzo efektywnym sorbentem dwóch pierwszych metali. Zbadano wpływ stężenia poszczególnych składników tych odpadów na sorpcję radionuklidów na CAA. Jony wapnia silnie zmniejszają sorpcję Sr(sup 2+), a EDTA w roztworach obojętnych sorpcję EU(sup 3+). Jony sodu, cytryniany i szczawiany mają niewielki wpływ na sorpcję Sr(sup 2)+ i EU(sup 3+). Radionuklidy Cs+ muszą być usuwane na innym sorbencie.