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1

Structural, morphological and photoluminescent properties of Nd-coated silicon nanostructures

Mefoued Amine, Mahmoudi Bedra, Benrekaa Nasser, Tiour Faiza, Menari Hamid, Naitbouda Abdelyamine, Manseri Amar, Brik Afaf, Mezghiche Salah, Debbab Moustafa

Opto-Electronics Review

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2023

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Vol. 31, No. 1

art. no. e145096

EN

The structural, morphological and photoluminescent properties of thermally evaporated neodymium oxide (Nd₂O₃) thin films deposited onto nanostructured silicon (Si-ns) are reported. Si-ns embedded in silicon nitride (SiN) thin films are prepared by plasma-enhanced chemical vapour deposition (PECVD). SiN and Nd₂O₃ thin films uniformity and Si-ns formation are confirmed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The presence of neodymium (Nd), silicon (Si), oxygen (O), and phosphorus (P) is investigated by energy-dispersive spectroscopy (EDS) and secondary ion mass spectrometry (SIMS). Post-annealing SIMS profile indicates an improvement of the homogeneity of activated P distribution in Si bulk. The X-ray diffraction (XRD) combined with Raman spectroscopy and Fourier-transform infrared spectroscopy (FTIR) have been employed to determine amorphous silicon (a-Si), crystalline silicon (c-Si), Nd₂O₃ and SiN phases present in the Nd₂O₃-SiN bilayers with their corresponding chemical bonds. After annealing, a Raman shift toward lower wavenumbers is recorded for the Si peak. XPS data reveal the formation of Nd₂O₃ thin films with Nd-O bonding incorporating trivalent Nd ions (Nd3+). Strong room-temperature photoluminescence is recorded in the visible light range from the Si-ns. Nd-related photoluminescent emission in the near infrared (NIR) range is observed at wavelengths of 1025-1031 nm and 1083 nm, and hence is expected to improve light harvesting of Si-based photovoltaic devices.

2

Management of the Rare Earth Elements (REE) in the Global Economy: Neodymiun Case Study

Sala Dariusz, Bieda Bogusław

Inżynieria Mineralna

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2023

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no. 2, vol. 2

29--35

EN

This study provides an overview of using rare earth elements (REEs) in global economy based on the permanent magnets consuming mainly a mixture of neodymium (Nd), praseodymium (Pr) and dysprosium (Dy), and cerium (Ce), as well as gadolinium (Gd) in much lower quantities. Actually the segment of the magnet market is the largest rare earth market (REM) by volume and will continue to outperform other market segments. In the report on „Rare Earths, Outlook to 2030” presented in Green Car Congress on the 3 February 2021 and developed by Roskill Commodity Research forecast, acquired in June 2021 by Wood Mackenzie, the leading global research, consultancy, and data analytics business powering the natural resources industry, Roskill forecasts that rare earth magnet applications will account for ~40% of total demand by 2030, raising the potential for a tight supply-demand balance for key magnetic REEs. The supply of rare earths on the US, Europe, Japan and Chinese markets is presented and discussed.

PL

Niniejsze opracowanie stanowi przegląd wykorzystania pierwiastków ziem rzadkich (REE) w gospodarce światowej w oparciu o magnesy trwałe zużywające głównie mieszaninę neodymu (Nd), prazeodymu (Pr) i dysprozu (Dy) oraz ceru (Ce), a także gadolin (Gd) w znacznie mniejszych ilościach. W rzeczywistości segment rynku magnesów jest największym rynkiem metali ziem rzadkich (REM) pod względem wolumenu i nadal będzie osiągał lepsze wyniki niż inne segmenty rynku. W raporcie „Rare Earths, Outlook to 2030” zaprezentowanym podczas Green Car Congress w dniu 3 lutego 2021 r. i opracowanym przez prognozę Roskill Commodity Research, nabytym w czerwcu 2021 r. przez Wood Mackenzie, wiodącą światową firmę zajmującą się badaniami, doradztwem i analityką danych, zasilającą biznes z branży zasobów naturalnych, Roskill prognozuje, że zastosowania magnesów ziem rzadkich będą stanowić ~40% całkowitego zapotrzebowania do 2030 r., co zwiększy potencjał ścisłej równowagi podaży i popytu w przypadku kluczowych magnetycznych REE. Przedstawiono i omówiono podaż pierwiastków ziem rzadkich na rynku USA, Europy, Japonii i Chin.

3

Side-pumped neodymium laser with self-adaptive, nonreciprocal cavity

Kaskow M., Galecki L., Zendzian W., Gorajek L., Jabczynski J. K.

Opto-Electronics Review

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2016

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Vol. 24, No. 1

10--14

EN

We demonstrate the generation of a near-diffraction-limited beam in a diode-side-pumped Nd:YAG slab laser with a nonreciprocal, self-adaptive cavity. The energy output of 228 mJ with 17.2% slope efficiency and 17.3% optical-to-optical efficiency was obtained.

4

Influence of the structural and surface properties on photocatalytic activity of TiO2:Nd thin films

Wojcieszak D., Mazur M., Kaczmarek D., Morgiel J., Poniedziałek A., Domaradzki J., Czeczot A.

Polish Journal of Chemical Technology

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2015

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Vol. 17, nr 2

103--111

EN

Titanium dioxide thin films doped with the same amount of neodymium were prepared using two different magnetron sputtering methods. Thin films of anatase structure were deposited with the aid of Low Pressure Hot Target Magnetron Sputtering, while rutile coatings were manufactured using High Energy Reactive Magnetron Sputtering process. The thin films composition was determined by energy dispersive spectroscopy and the amount of the dopant was equal to 1 at. %. Structural properties were evaluated using transmission electron microscopy and revealed that anatase films had fibrous structure, while rutile had densely packed columnar structure. Atomic force microscopy investigations showed that the surface of both films was homogenous and consisted of nanocrystalline grains. Photocatalytic activity was assessed based on the phenol decomposition. Results showed that both thin films were photocatalytically active, however coating with anatase phase decomposed higher amount of phenol. The transparency of both thin films was high and equal to ca. 80% in the visible wavelength range. The photoluminescence intensity was much higher in case of the coating with rutile structure.

5

Uranium and neodymium partitioning in alkali chloride melts using low-melting gallium-based alloys

Melchakov S. Y., Maltsev D. S., Volkovich V. A., Yamshchikov L. F., Lisienko D. G., Osipenko A. G., Rusakov M. A.

Nukleonika

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2015

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Vol. 60, No. 4, part 2

915--920

EN

Partitioning of uranium and neodymium was studied in a ‘molten chloride salt – liquid Ga-X (X = In or Sn) alloy’ system. Chloride melts were based on the low-melting ternary LiCl-KCl-CsCl eutectic. Nd/U separation factors were calculated from the thermodynamic data as well as determined experimentally. Separation of uranium and neodymium was studied using reductive extraction with neodymium acting as a reducing agent. Efficient partitioning of lanthanides (Nd) and actinides (U), simulating fission products and fissile materials in irradiated nuclear fuels, was achieved in a single stage process. The experimentally observed Nd/U separation factor valued up to 106, depending on the conditions.

6

Właściwości wielofunkcyjnych cienkich warstw TiO2:Nd z przeznaczeniem na powierzchnię ogniw słonecznych

Mazur M., Kaczmarek D., Wojcieszak D., Morgiel J., Kalisz M., Szymańska M.

Elektronika : konstrukcje, technologie, zastosowania

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2014

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Vol. 55, nr 8

43-46

PL

W pracy przedstawiono wyniki badania wpływu domieszkowania neodymem na właściwości wielofunkcyjne cienkich warstw dwutlenku tytanu. Cienkie warstwy zostały wytworzone za pomocą dwóch metod rozpylania magnetronowego: niskociśnieniowej oraz wysokoenergetycznej. W zależności od zastosowanej metody wytwarzania, naniesione powłoki miały strukturę krystaliczną anatazu lub rutylu. Zastosowanie domieszki neodymu umożliwiło uzyskanie mniejszego współczynnika odbicia światła od powierzchni krzemu w porównaniu do klasycznych powłok niedomieszkowanego TiO2. Jak pokazały przedstawione w pracy badania, wytworzone cienkie warstwy domieszkowane neodymem były wielofunkcyjne – powłoki o strukturze anatazu miały bardzo dobre właściwości fotokatalityczne i antystatyczne, natomiast warstwy o strukturze rutylu zwiększoną twardość.

EN

In this paper the results of the influence of neodymium doping on the properties of multifunctional titanium dioxide thin films were shown. Thin films were manufactured using two various magnetron sputtering methods: low-pressure and high-energy. Depending on the preparation method, deposited coatings were of the anatase or of the rutile structure. As it is shown in the paper doping with neodymium caused the decrease of reflection coefficient from silicon surface as compared to undoped TiO2. Thin films doped with neodymium were multifunctional – coatings with anatase structure were photocatalytically active and antistatic, while coatings with rutile structure had increased hardness.

7

Novel constructions of optical fibers doped with rare – earth ions

Dorosz J.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2014

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Vol. 62, nr 4

619--626

EN

In the paper the research on rare-earth doped and co-doped optical fibre conducted in the Laboratory of Optical Fiber Technology at the Bialystok University of Technology is presented. Novel active fibre constructions like multicore, helical-core and side detecting ribbon/core optical fibers were developed with a targeted focus into application. First construction i.e. multicore RE doped optical fibers enable supermode generation due to phase - locking of laser radiation achieved in a consequence of exchanging radiation between the cores during the laser action. In the paper a far - field pattern of 19 - core optical fiber-doped with Yb3+ ions, registered in the MOFPA system, showed centrally located peak of relatively high radiation intensity together with smaller side-lobes. Another new construction presented here is helical-core optical fibers with the helix pitch from several mm and the off-set ranging from 10 μm to 200 μm. The properties of helical-core optical fiber co-doped with Nd3+/Yb3+ were also discussed. In the field of sensor applications novel construction of a sidedetecting luminescent optical fiber for an UV sensor application has been presented. The developed optical fiber with an active core/ribbon, made of phosphate glass doped with 0.5 mol% Tb3+ ions, was used as a UV sensing element.

8

Structural and surface properties of TiO2 thin films doped with neodymium deposited by reactive magnetron sputtering

Mazur M., Kaczmarek D., Domaradzki J.

Materials Science Poland

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2013

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Vol. 31, No. 1

71-79

EN

Thin films were deposited using modified, high energy magnetron sputtering method from Ti-Nd mosaic targets. The amount of neodymium dopant incorporated into two sets of thin films was estimated to be 0.8 and 8.5 at.%, by means of energy dispersive spectroscopy. On the basis of x-ray diffraction method, the type of crystalline structure and crystallites size were evaluated directly after the deposition process and after additional post-process annealing at 800 °Ctemperature. The influence of annealing on the surface properties was evaluated with the aid of atomic force microscopy. Uniformity of the dopant distribution in titanium dioxide matrix was examined with the aid of secondary ion mass spectroscopy. Additionally, using atomic force microscope, diversification and roughness of the surface was determined. Chemical bonds energy at the surface of TiO2:Nd thin films was investigated by x-ray photoelectron spectroscopy method. Wettability measurements were performed to determine contact angles, critical surface tensions and surface free energy of prepared coatings. On the basis of performed investigations it was found, that both factors, the amount of neodymium dopant and the post-process annealing, fundamentally influenced the physicochemical properties of prepared thin films.

9

Photocatalytic properties of transparent TiO2 coatings doped with neodymium

Wojcieszak D., Kaczmarek D., Domaradzki J., Mazur M., Morawski A. W., Janus M., Prociów E., Gemmellaro P.

Polish Journal of Chemical Technology

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2012

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Vol. 14, nr 3

1-7

EN

In this work photocatalytic properties of TiO2 thin fi lms doped with 8.51 at. % of Nd were described. The self-cleaning phenomenon of thin fi lms was discussed together with the structural, optical and surface properties of prepared thin fi lms. Transparent coatings based on titanium dioxide were manufactured by high-energy reactive magnetron sputtering process. Incorporation of Nd during sputtering process results in amorphous behavior, without a signifi cant infl uence on transparency and colour as compared to the undoped TiO2-rutile matrix. Nevertheless, doping with neodymium doubles the photocatalytic activity of the matrix due to higher quantity of photo-generated charge carriers and more effi cient mechanism of energy transfer.

10

Światłowód wielordzeniowy domieszkowany jonami Nd3+ do budowy włóknowych źródeł promieniowania koherentnego

Kochanowicz M., Żmojda J., Dorosz D.

Materiały Ceramiczne

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2012

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T. 64, nr 4

584-588

PL

W artykule przedstawiono fazowanie w światłowodzie 19-rdzeniowym domieszkowanym Nd3+. Przeanalizowano wpływ parametrów materiałowych i geometrycznych aktywnego światłowodu 19-rdzeniowego oraz wpływ odchylenia od uzgodnionej fazy promieniowania na współczynnik jakości wiązki laserowej w obszarze dyfrakcyjnym dalekiego pola. Współczynnik jakości wiązki laserowej w wytworzonym światłowodzie wynosi BQF = 0,71, gdzie V = 2,4, d = 18 žm. Wykorzystując opracowany model generacji supermodu w wielordzeniowym laserze włóknowym zbadano wpływ sprzężenia między rdzeniami na różnicę fazy promieniowania w poszczególnych rdzeniach w czasie rozwoju akcji laserowej. W rezultacie przeprowadzonych analiz numerycznych zaprojektowano i wytworzono dwupłaszczowy 19-rdzeniowy światłowód domieszkowany jonami neodymu. Ponadto, zmierzono jego widmo luminescencji oraz obraz pola dalekiego.

EN

In the paper, the phase-locking of the 19-core optical fibre doped with Nd3+ is presented. The influence of material and geometrical parameters of the active 19-core optical fibre and phase deviation on the beam quality factor of the laser beam in the far-field diffraction region has been analysed. The beam quality factor of the manufactured multicore fibre equals BQF = 0.71, when V = 2.4 and d = 18 žm. Based on a developed model of supermode generation in the multicore fibre laser, the impact of the coupling value between the cores on the difference in radiation phases between particular emitters during the development of the laser action was considered. As a result of the conducted analysis, a double-clad 19-core optical fibre doped with neodymium ions has been designed and manufactured, and its luminescence spectra and far field diffraction pattern have been measured.

11

Oddziaływania magnetyczne w technice przeniesienia napędu

Tomas A.

Maszyny Górnicze

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2012

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R. 30, nr 2

27-33

PL

W artykule scharakteryzowano materiał magnetyczny nowej generacji - neodym, w aspekcie możliwości stosowania go w sprzęgłach magnetycznych. Przedstawiono kierunki rozwoju przekładni magnetycznych. Omówiono prace nad wykorzystaniem oddziaływań magnetycznych w technice przeniesienia napędu, prowadzone w Instytucie Techniki Górniczej KOMAG. Zaprezentowano stanowisko do symulacji i badania układów magnetycznych, przeznaczonych do przeniesienia momentu obrotowego.

EN

Magnetic material of new generation - neodymium is characterized in the paper in the aspect of its application in magnetic couplings. Directions of development of magnetic gears are presented. Work on use of magnetic interactions in drive transmission technology, which is carried out at the KOMAG Institute of Mining Technology, is discussed. A facility for simulation and testing of magnetic systems, which are designed for torque transmission, is presented.

12

Wpływ wygrzewania na nanokrystaliczne cienkie warstwy na bazie TiO₂ na przykładzie TiO₂:Nd

Mazur M., Wojcieszak D., Sieradzka K., Kaczmarek D., Domaradzki J., Prociów E. L.

Elektronika : konstrukcje, technologie, zastosowania

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2012

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Vol. 53, nr 2

16-18

PL

W artykule przedstawiono wyniki badania wpływu wygrzewania na właściwości strukturalne oraz właściwości powierzchni nanokrystalicznych cienkich warstw TiO₂ domieszkowanych neodymem (0,84% at.). Cienkie warstwy TiO₂:Nd wytworzono zmodyfikowaną metodą rozpylania magnetronowego i bezpośrednio po naniesieniu miały one strukturę amorficzną. Wygrzewanie w 800°C spowodowało rekrystalizację struktury w anataz o wielkości krystalitów równych 6 nm. Mikroskopia sił atomowych potwierdziła nanokrystaliczność badanych cienkich warstw.

EN

In this paper results of annealing influence on structural and surface properties of nanocrystalline TiO₂:Nd (0.84 at.%) thin films have been shown. Thin films have been deposited using modified magnetron sputtering process. As-deposited TiO₂:Nd thin films revealed amorphous structure. Additional annealing at 800°C caused the appearance of anatase phase with crystallites size of 6 nm. Atomic force microscopy confirmed nanoery-stallinity of investigated thin films.

13

Preparation and characterization of transparent Nd:YAG ceramics

Librant Z., Jabczyński J. K., Węglarz H., Wajler A., Tomaszewski H., Łukasiewicz T., Żendzian W., Kwiatkowski J.

Opto-Electronics Review

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2009

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Vol. 17, No. 1

72-77

EN

Transparent Nd:YAG ceramics were produced by solid.state reaction of high.purity (4N) nanometric oxides powders, i.e., Al₂₃O₃, Y₂₃O₃ and Nd₂₃O₃. After sintering, mean grain sizes of 2% Nd:YAG samples were about 20 µm and their transparency were a bit worse than that of 0.9% Nd:YAG single crystal. Two types of active elements: rods and slabs were fabricated and characterized in several diode pumping schemes. In end pumping configuration as a pump source 20.W fiber coupled laser diode operating in low duty cycle regime (1 ms pump duration/20 Hz) was deployed. In the best case, 3.7 W of output power for 18 W of absorbed pump power, M ² < 1.4 were demonstrated for uncoated ceramics Nd:YAG rod of Φ 4×3mm size in preliminary experiments. For the ceramics of two times lower Nd dopant level above 30% slope efficiency was achieved. In case of Nd:YAG ceramic slab side pumped by 600.W laser diode stack above 12 W was demonstrated with slope efficiency of 3.5%.

14

Badanie emisji krótkofalowej w domieszkowanych jonami Nd 3+ szkłach niskofononowych

Klimczak M., Piramidowicz R., Malinowski M.

Elektronika : konstrukcje, technologie, zastosowania

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2008

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Vol. 49, nr 9

52-56

PL

Praca stanowi podsumowanie prowadzonych badań właściwości emisyjnych szkieł fluorocyrkonowych (ZBLAN) domieszkowanych jonami Nd 3+ w stosunkowo słabo zbadanym zakresie spektralnym fioletu i bliskiego UV. Zakres pracy obejmuje w szczególności badania i analizę charakterystyk absorpcji i emisji oraz widm wzbudzeniowych, jak również analizę dynamiki fluorescencji wysokoenergetycznych poziomów metastabilnych jonu neodymu w szkle ZBLAN o różnych koncentracjach domieszki oraz zidentyfikowanie i analizę procesów konwersji wzbudzenia umożliwiających uzyskanie emisji antystokesowskiej w zakresie krótkofalowym.

EN

This work summarizes research dedicated to emission properties of fluorozicronate glass (ZBLAN type) doped with Nd 3+ ions in the weakly explored UV-violet spectral range. Scope of work encompasses specifically measurement and analysis of absorption and emission, as well as excitation spectra. Additionally, fluorescence dynamics is studied in context of high-energy metastable states of neodymium ions doped into ZBLAN at different concentrations. Experimental part is followed by identification and analysis of up-conversion processes leading to anti-stokes emission in the short-wavelength part of spectrum.

15

Światłowód pierścieniowy domieszkowany neodymem.

Dorosz D.

Szkło i Ceramika

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2006

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R. 57, nr 2

14-18

EN

Signal processing, device oriented, ring-index fibers have a unique capability of transmitting either quasi planar modes for large ring diameters or the second order mode in a quasi single-mode regime at lossy discrimination of the fundamental mode, for small ring diameters. Ring-index fibres can maintain single mode transmission for considerable values of normalized frequency for particular cases of the refractive index profile. Theoretically predicted features of ring index fibres were confirmed experimentally on the samples manufactured by the author. The ring shape of doped rare earth core gives possibility to stimulate luminescence from inside of the fibre. In this paper the ring core doped Nd3+ ions fibre is reported. The analysis of dependences between parameters of core on light propagation in ring-core optical fibers is presented. The ring core is made from silica glasses doped by Nd3+ ions.

16

Investigation of Heteropoly Niobotungstolanthanidate Ions Equilibria in the Aqueous Solutions at Different Ionic Strengths

Rozantsev G., Radio S., Kozlova T.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 2

235-245

EN

The condensation process in the system: Ln3+-H3Nb6O19 5 -WO4 2 -OH-(H+)-H2O (Ln = Ho, Nd; ni(Nb):ni(W) = 9:1) has been investigated. According to the results of potentiometric titrations, the model of the condensation process has been proposed. Diagrams of mixed heteropoly niobotungstolanthanidate anions (HPNTLA) distribution within an intervals ZH+ = [ni(H+ )]/[ni(W) + ni(Nb)] = 0.00÷0.30 and ZOH- = [_(OH-)]/[ni(W) + ni(Nb)] = 0.00÷0.36 have been drawn. It has been shown that at Z H+ > 0.30 there occurs a destruction of heteropolyanions (HPA). Concentration and thermodynamic constants of HPA formation have been determined. Existence of HPNTLA has been confirmed by chemical and IR-spectroscopic analyses of Tl6H4[HoNb9W(OH)8O28]ni4.0H2O, which was isolated from a solution with Z H+ = 0.08. It has also been shown, that HPNTLAkeeps the ratio of Nb:W = 9:1 within the entire interval ZOH-. The main destruction phases of Tl6H4[HoNb9W(OH)8O28]x4.0H2O have been determined by X-ray powder diffraction analysis.

17

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.

18

Derivative spectrophotometry in resolution of overlapping spectra of La, Pr, Nd and Sm complexes with bromopyrogallol red (BPR)

Bobrowska-Grzesik E., Kozłowska K.

Polish Journal of Applied Chemistry

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2004

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Vol. 48, nr 1-2

45-49

EN

The absorption spectra of lanthanum, praseodymium, neodymium and samarium complexes with bromopyrogallol red have been studied by 1-3rd derivative spectrophotometry. Conditions have been found allowing separation of lanthanum spectra from other investigated ions. The following wavelengths were applied for measuring values of 1-st derivative signal: l=672, 666, or 664 respectively for lanthanum determination in the presence of praseodymium, neodymium or samarium ions and l=686nm for the determination of these ions in the mixtures with lanthanum. The Beer's law is obeyed in the range 0.2-3 mg Ln/ml. Detection limit is 0.05 mg/ml for La. The procedure allows determination of La in two compound mixtures of selected rare earths with satisfactory results.

PL

Badano możliwość rozdzielenia widm absorpcyjnych kompleksów lantanu, prazeodymu, neodymu i samaru z czerwienią bromopirogllolową za pomocą spektrofotometrii pochodnej 1 - 3 rzędu. Znaleziono warunki, w których możliwe było rozdzielenie widm kompleksów lantanu od pozostałych badanych jonów. Następujące długości fali wykorzystano dla pomiaru wartości sygnału 1-ej pochodnej widma: l = 672, 666 lub 664nm dla oznaczania lantanu w obecności prazeodymu, neodymu lub samaru oraz l=686nm dla oznaczania tych jonów w mieszaninie z lantanem. Prawo Beera spełnione jest w zakresie 0.2-3mgLn/ml, limit detekcji dla La wynosi 0.05 mg/ml. Procedura pozwala na oznaczanie mikrogramowych ilości lantanu w dwuskładnikowych mieszaninach wybranych pierwiastków ziem rzadkich.

19

Synthesis and luminescence properties of nanocrystalline BaTiO3:Nd3+ obtained by sol-gel methods

Pązik R., Hreniak D., Stręk W.

Materials Science Poland

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2004

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Vol. 22, No. 3

210--225

EN

Neodymium-doped barium titanate (BaTiO3) nanocrystalline powders were prepared by the sol-gel method. Structure and average grain sizes were analysed by X-ray powder diffraction (XRD) measurements. Grain sizes amount from 30 to 60 nm, depending on dopant concentration and sintering temperature. The luminescence properties of BaTiO3:Nd3+ were investigated as a function of the concentration of Nd3+ (0.5-2 mol %) and sintering temperature (700-1050 ?C). The influence of Nd3+ concentration on the grain size and crystal structure of BaTiO3 nanocrystallite powders was found and a weak hot emission from the 4F5/2 level was observed for the nanopowders obtained.

20

Analysis of optical transitions of Nd3+ in YAG nanocrystallites

Bednarkiewicz A.

Materials Science Poland

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2004

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Vol. 22, No. 3

211--217

EN

A novel approach to the analysis of optical transitions in Nd3+-doped nanocrystallites is put forward, based on the Judd-Ofelt analysis of luminescence transitions associated with the 4F3/2›4I11/2 and 4F3/2›4I9/2 bands. The procedure, requiring neither information on Nd3+ concentration nor transparent samples, greatly simplifies calculation of branching ratios of neodymium 4F3/2 ›4IJ. The technique seems to be very useful in the spectroscopic assessment of Nd3+-doped materials for laser and optoelectronic purposes. The effect of grain size in nanometric ceramics on the branching ratio is considered.