Luminescence Of Nd3 Research Articles

Impact of the Sr2+-Nd3+ heterovalent isomorphism on the luminescence of orthoborates in Sr3B2O6-NdBO3 system

The phase diagram of the Sr3B2O6-NdBO3 binary system was studied. The intermediate compound Sr3Nd2(BO3)4 can be synthesized over a wide range of compositions, from 27 to 70 mol.% NdBO3, at 1200°C. The maximum luminescence of Nd in this solid solution was measured for the highest content of Sr. The partial substitution of Nd by 3 mol.% Sr in NdBO3 does not significantly affect the presence of concentration quenching. The phase exhibiting the strongest luminescence within the system is neodymium doped Sr3B2O6.

Rapid and reliable ratiometric fluorescence detection of isoquercitrin based on a high-nuclearity Zn(II)-Nd(III) nanomolecular sensor

Rapid and quantitative detection of isoquercitrin (Isq) has been attracting much attention due to its outstanding pharmacological and physiological activities. Herein, an interesting 48-metal Zn(II)-Nd(III) nanocluster (1, molecular sizes 1.3 × 2.8 × 3.1 nm) with salen-type Schiff base ligand was constructed as molecular sensor for the luminescence detection of Isq. 1 exhibits visible ligand-centered emission and NIR luminescence of Nd(III), and shows ratiometric fluorescence response to Isq with high sensitivity even in the presence of other interferences. The fluorescence sensing behavior can be expressed by a second-order equation I1060nm/I480nm = A*[Isq]2 + B*[Isq] + C, which is used to quantitatively analyze the Isq concentrations in DMF and FCS. The LODs to Isq for the ligand-centered and lanthanide emissions of 1 in DMF are 0.21 μM and 0.11 nM, respectively. The quenching of the ligand-centered emission of 1 caused by Isq is attributed to the competitive absorption of light energy and “inner effect”, while, the luminescence enhancement is due to the “antenna effect”.

Luminescence of Nd3+-doped LaF3 glass-ceramics enhanced with Ag nanoparticles

Nd3+-doped, LaF3-based, transparent oxyfluoride glass-ceramics (GCs) containing Ag nanoparticles (NPs) have been prepared by a melt-quenching method. Different Ag-containing precursors were employed, with AgNO3 as the most suitable for obtaining Ag NPs segregated in the glassy matrix. Transmission electron microscopy and X-ray absorption spectroscopy determined the presence of Ag0 NPs, with higher concentrations in glass-ceramics produced in an inert atmosphere (N2).The spectral features of emission and excitation spectra, in addition to the different lifetimes of the 4F3/2 state in the co-doped samples with Ag NPs, demonstrate the incorporation of Nd3+ ions into the LaF3 nanocrystals. The relative contribution to the emission from Nd3+ in the nanocrystals depends on the Ag concentration and atmosphere. The glass-ceramic co-doped with 0.2 wt% Ag, thermally treated in N2, exhibits the highest contribution of emissions attributable to Nd3+ ions in the crystalline phase. The crystalline fraction is similar to that of a Ag-free sample synthesized under analogous conditions. This increase of the luminescence is likely attributable to the enhancement of the local electric field in the LaF3 nanocrystals due to the presence of Ag0 NPs.

Construction of three novel Ln3 compounds using multidentate Schiff base ligand: Crystal structures, fluorescence properties, and biological activities

Three new trinuclear lantharide-based compounds: [Ln3(dbm)5(L)2(CH3OH)]·CH2Cl2 (LnIII = Nd(1), Sm(2), and Tb(3), dbm− = diphthaloylmethae) have been synthesized via the solvothermal method by using a polydentate Schiff base ligand (H2L = (E)-6-(hydroxymethyl)-N'-((6-methoxypyridin-2-yl)methylene)picolinohydrazide) reacting with Ln(dbm)3·2H2O. X-ray diffraction study reveals that all compounds 1–3 belong to monoclinic crystal system with space group C2/c, and compounds 1–3 are isostructural and possess a broken-line Ln3 core. The solid-state luminescence properties measurements indicate that compound 3 displays the characteristic lanthanide luminescence at room temperature. Moreover, photoluminescence properties study show that 1 and 2 display typical NIR luminescence of Nd(III) and Sm(III) ions at room temperature. Furthermore, biological activities research reveals that compounds 1–3 have greater antibacterial activity than the ligand H2L and Ln(dbm)3·2H2O (LnIII = Nd (1), Sm (2), and Tb (3)). The interaction between compounds 1–3 and calf thymus DNA was studied and the results revealed that the compounds were mainly intercalated with calf thymus DNA.

Optical Multisensor System Based on Lanthanide(III) Complexes as Near-Infrared Light Sources for Analysis of Milk

Optical multisensor systems are easy-to-use and inexpensive analytical devices. In this work, we propose an optical multisensor system based on the luminescence of Nd(III) and Yb(III) complexes in the near-infrared (NIR) spectral region. The observed emission bands play the role of secondary light sources for further analysis of milk—for the determination of fat content and for the recognition of adulteration. The samples for analysis were prepared by putting a drop of milk upon a thin glass covering the powdered mixture of lanthanide complexes, which were excited by a light-emitting diode (LED) in the ultraviolet region (the maximum intensity at 365 nm). The diffuse-reflectance spectra of samples were acquired in the short-wave NIR range 750–1100 nm using a portable NIR spectrometer. The developed optical system was tested using two sets of milk samples with varying concentration levels of fat and added urea. The obtained spectral data were analyzed using a number of multivariate prediction and classification methods of chemometrics and the results were statistically compared. The regression and classification model performances achieved in this proof-of-concept study illustrate the feasibility of the optical multisensor analysis based on luminescent light sources in the short-wave NIR range, in particular, for their application in the dairy.

Modulation of thermometric performance of single-band-ratiometric luminescent thermometers based on luminescence of Nd3+ activated tetrafluorides by size modification

Due to a number of its advantages, luminescence thermometry has been a strongly developed strand of temperature metrology over a period of time. Although there are several different types of luminescent thermometers, recently attention has been focused on a new single-band ratiometric approach, which is based on the excited state absorption phenomenon. Nevertheless, since this process is nontrivial and has not been studied extensively in the context of thermometry to date, a number of studies are necessary to enable the intentional development of highly sensitive thermometers based on this method. One of the important aspects is to investigate the influence of material size and the associated occurrence of surface effects, which is considered in this work. In addition, the research in this paper has been extended to explore the aspect of host material composition. Accordingly, nanocrystals and microcrystals of β-NaYF4:2%Nd3+, β-NaGdF4:2%Nd3+, and LiGdF4:2%Nd3+ were investigated in this work. The influence of surface effects on thermometric parameters was proved, with special emphasis on the useful temperature range. Thus, by increasing the particle size, it was possible to intentionally extend the useful range by even more than 100 K.

NIR luminescence, hypersensitivity in the 4f ‒ 4f absorption spectra and NMR of seven-, eight- and nine-coordinate ternary neodymium(III) complexes

Four new Nd (III) ternary complexes of [Nd(fod) 3 (H 2 O)] where fod is the anion of 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedione with monodentate (indazole and triphenylphosphine oxide (tppo)), bidentate (2-(1H-imidazole-2-yl)pyridine (impy)) and tridentate (2,4,6-tris(2-pyridyl)- s -triazine (tptz)) ancillary ligands. The isolated complexes [Nd(fod) 3 (tptz)] ( 1 ), [Nd(fod) 3 (indazole)] ( 2 ), [Nd(fod) 3 (impy)] ( 3 ) and [Nd(fod) 3 (tppo) 2 ] ( 4 ) have been characterized by elemental analysis, TGA, DTA, 1 H NMR and infra-red spectroscopy. The optical absorption in different solvents is studied and evaluated in terms of oscillator strength and band shape. The oscillator strength of the hypersensitive transition of the most asymmetric seven-coordinate indazole complex ( 2 ) is highest among the complexes in any given solvent and this strengthens the premise that the oscillator strength depends upon symmetry of the complex. The solution and solid-state near IR luminescence, decay curves and intrinsic quantum yield of these complexes are investigated and discussed. Most importantly, the replacement of water molecule from the inner coordination sphere of [Nd(fod) 3 (H 2 O)] with different ancillary ligands markedly boosts the decay time (τ = 1.37μs ([Nd(fod) 3 (H 2 O)]); 5.52 μs ( 1 ); 2.29 μs ( 2 ); 4.04 μs ( 3 ) and 3.95 μs (4) in chloroform solution and (2.29 μs (Nd(fod) 3 (H 2 O)]); 9.15 μs ( 1 ); 4.27 μs ( 2 ); 8.27 μs ( 3 ) and 6.24 μs (4) in solid state) and intrinsic quantum yield (Φ Nd % = 0.54 ([Nd(fod) 3 (H 2 O)]); 2.21 ( 1 ); 1.03 ( 2 ); 1.61 ( 3 ) and 1.58 (4) in chloroform solution and (0.91% ([Nd(fod) 3 (H 2 O)]); 3.66 ( 1 ); 1.71 ( 2 ); 3.31 ( 3 ) and 2.49 (4) in solid state). The luminescence observed from the present complexes entails positive effect of the ancillary ligands on luminescence of Nd (III). The energy transfer process is discussed. In this work, we correlate the luminescence intensity with the nature of ancillary ligand, coordination geometry and energy difference. • Four new ternary complexes [Nd(fod)3(X)], (X = 1 for tptz, indazole, impy and 2 for tppo] have been synthesized and characterized • The optical absorption in different solvents is studied and evaluated in terms of oscillator strength and band shape. • Solution and solid-state NIR luminescence, decay curves and intrinsic quantum yield are investigated and discussed. • Presence of perfluoryl groups, substitution of water by ancillary ligands markedly boosts the decay time and quantum yield • Luminescence intensity is correlated with ancillary ligands, coordination geometry and energy difference

Near infrared luminescence of Nd, Er and Yb complexes with perfluorinated 2-mercaptobenzothiazolate and phosphine oxide ligands

In order to obtain new NIR luminescent lanthanide complexes free of C-H and C-O bonds the perfluorinated 2-mercaptobenzothiazolate (mbtF) was used as organosulphide antenna ligand and the perfluorinated triphenylphosphine oxide (TPPOF) was used to saturate the coordination sphere of the lanthanide ion. Targeted complexes Ln(mbtF)3(TPPOF)2 (Ln = Nd(1), Er(2) and Yb(3)) were synthesized in high yields from respective silylamides Ln[N(SiMe3)2]3, HmbtF and TPPOF using dry toluene as a solvent. Upon near UV light excitation the compounds 1–3 in the solid state showed an intense NIR photoluminescence which is characteristic for corresponding lanthanide ions. This luminescence was studied at a room temperature by time-resolved methods. The study revealed the presence of intermediate f-f transitions in the time resolved photoluminescence spectrum of 2. The measured lifetimes of Nd and Er NIR emission in 1 and 2 are 39.5 and 53.5 μs respectively. It was found that these lifetimes are among the longest for neat erbium and neodymium complexes with organic ligands.

Nd3+/Yb3+ co-doped mid-infrared luminescence fluorobromide glass with energy transfer and zero-thermal-quenching IR emission

Nd3+/Yb3+ co-doped fluorobromide glass samples were prepared by melt quenching. The mid-infrared (MIR) luminescence of the Nd3+/Yb3+ co-doped fluorobromide glass was investigated by Br-doping reduces the phonon state density of the matrix. The 3.9 μm MIR luminescence of the samples excited at 793 and 980 nm pump excitation was investigated in detail. There is an effective mutual energy transfer process between Nd3+ and Yb3+. It is proved under 793 nm excitation that the luminescence of Nd3+ at 3.9 μm is reduced by effective energy transfer from Nd3+:2H11/2 → Yb3+:2F5/2. At the same time, it is proved that the effective energy transfer from Yb3+:2F5/2 → Nd3+:2H11/2 under the excitation of 980 nm enhances the luminescence of Nd3+ at 3.9 μm. In addition, it is found that the samples still have good infrared (IR) luminescent properties when the temperature changes. The emission cross-sectional area and the absorption cross-sectional area are σem (3.87 × 10−20 cm2) and σabs (4.25 × 10−20 cm2). The fluorescence decay characteristics of the sample at 3.9 μm at the 2H11/2 level were investigated and the fluorescence lifetime was calculated. The gain performance of the sample was calculated and analyzed, which can reach 4.25 × 10−20 cm2. Those results prove that Nd3+/Yb3+ co-doped fluorobromide glass is the potential mid-infrared laser gain material.

Construction of a 18-Metal Neodymium(III) Nanoring with NIR Luminescent Sensing to Antibiotics.

One 18-metal Nd(III) nanoring, [Nd18(L1)8(HL2)2(OAc)20(MeOH)8(EtOH)6(H2O)4]·2(MeOH)·6(H2O) (1), was constructed by the use of a hexadentate Schiff base ligand. For 1, the near-infrared (NIR) luminescence of Nd(III) was detected under the excitation of absorption band at 371 nm. The study of luminescent sensing properties exhibits that, even with the existence of other antibiotics, this Nd(III) nanoring displays high sensitivity and selectivity to nitrofuran antibiotics (NFAs). The luminescence quenching constants and limits of detection of 1 to NFAs are found to be 1.4 × 104 to 3.5 × 104 M-1 and 0.9-2.2 μM, respectively.

One Nanoscale Zn(II)-Nd(III) Complex With Schiff Base Ligand: NIR Luminescent Sensing of Anions and Nitro Explosives.

One Zn-Nd complex [Zn2Nd4L2(OAc)10(OH)2(CH3OH)2] (1) was synthesized from Schiff base ligand bis(3-methoxysalicylidene)ethylene-1,2-phenylenediamine (H2L). 1 shows nanoscale rectangular structure with sizes of about 0.8 × 1.1 × 2.8 nm. 1 exhibits typical near-infrared luminescence of Nd(III) under the excitation of UV-visible light. Further study shows that the complex displays luminescent response behavior to anions and nitro explosives, especially with high sensitivity to H2 and 2,4,6-trinitrophenol.

Near-infrared excitation and emitting thermometer based on Nd3+ doped ytterbium molybdate with thermally enhanced emissions

Lanthanides doped optical materials with temperature sensing property are of great interest for optical thermometry. However, most lanthanides doped luminescent materials for ratiometric thermometer are often accompanied by thermal quenching, which leads to a decrease in temperature sensing performance. Here, Nd3+ doped Yb2Mo3O12 phosphor with near-infrared upconversion emissions has been fabricated. A non-contact thermometer is constructed with the luminescence of Nd3+ ions and the change of the emission peak height ratio of 4F7/2-4I9/2 and 4F5/2-4I9/2 transitions. Interestingly, the intensity of the emission peaks in the prepared phosphor increases with increasing temperature. Avoiding thermal quenching, the thermally enhanced upconversion emission affords high sensing accuracy. The maximum relative and absolute sensitivity was 1.186% and 9.789 × 10−3 K−1, respectively. The results suggest that appropriate emission bands with thermal population are benefit for optical ratiometric thermometers.

VISUALIZATION OF Nd3+-DOPED LaF3 NANOPARTICLES FOR NEAR INFRARED BIOIMAGING VIA UPCONVERSION LUMINESCENCE AT MULTIPHOTON EXCITATION MICROSCOPY

Recent developments in the field of biophotonics facilitate the raise of interest to inorganic nanoparticles (NPs) doped with Nd 3+ ions, because of their near-infrared (NIR) absorption. These NPs are interesting bioimaging probes for deep tissue visualization, while they can also act as local thermometers in biological tissues. Despite the good possibilities for visualization of NPs with Nd3+ ions in NIR spectral range, difficulties arise when studying the cellular uptake of these NPs using commercially available fluorescence microscopy systems, since the selection of suitable luminescence detectors is limited. However, Nd 3+ ions are able to convert NIR radiation into visible light, showing upconversion properties. In this paper we found optimal parameters to excite upconversion luminescence of Nd 3+ +:LaF NPs in living cells and to compare the distribution of the NPs inside the cell culture of human macrophages THP-1 obtained by two methods. Firstly, by detecting the upconversion luminescence of the NPs inVIS under NIR multiphoton excitation using laser scanning confocal microscopy and secondly, using transmission electron microscopy.

Synthesis of gold nanorod/neodymium oxide yolk/shell composite with plasmon-enhanced near-infrared luminescence.

A yolk/shell composite consisting of an AuNR core and an Nd2O3 shell with a 19 nm gap is synthesized by a multi-step over-growth method. The near-infrared luminescence of AuNR@Nd2O3 is up to 4.6 times higher than that of Nd2O3 hollow nanoparticles. The underlying mechanism of plasmon-induced luminescence enhancement is further investigated.

Compressed energy transfer distance for remarkable enhancement of the luminescence of Nd3+-sensitized upconversion nanoparticles

We developed a compressed activator layer (NaYF4:Yb/Er) and a Nd sensitizer layer (NaYF4:Nd) for enhancing (enhancement factor ∼19.8) the upconversion luminescence of ∼808 nm excited-, Nd3+-sensitized nanoparticles.

IR Luminescence of Nd3+, Sm3+, and Yb3+ β-Diketonates in Different Aggregate States

The influence of the aggregate state on the IR luminescence is studied for the Nd(III), Sm(III), and Yb(III) complexes with the thienyl, phenyl, and alkyl derivatives of acetylacetone in solutions and as sorbates on the polymer matrix. It is found that the luminescence intensity of the sorbates of the complexes is 2–3 orders of magnitude higher than that in solutions due to the elimination of diffusion and respective intermolecular nonradiative losses of the excitation energy.

Synthesis and properties of Nd-doped oxynitride phosphate laser glasses

The substitution of nitrogen for oxygen in phosphate glasses improves the chemical, thermal and mechanical properties and particularly reduces their very high hygroscopic character, although the preparation of homogeneous and free of defects oxynitride bulk phosphate glasses through ammonolysis represents a big challenge. This work reports on the synthesis and properties of a series of Nd-doped oxynitride phosphate glasses with composition Na0.3K0.3Ba0.2PO3-3x/2Nx that may find application as laser hosts. Whereas the glass transition temperature, elastic modulus and index of refraction show a regular increase with the nitrogen content that agrees with previous studies, the effect of nitrogen onto the luminescence of Nd3+ ions appears to be more complicated. The average lifetime of the decay from the 4F3/2 level decreases with the N/P ratio of the glasses, which is thought to be mainly due to the presence of water from the ammonolysis reaction. However, further thermal treatments under N2 flow of an oxynitride glass have shown an important reduction of the water content as well as a drastic increase of the luminescence lifetime of Nd3+, this being a promising method for the development of laser phosphate glasses having good chemical and mechanical properties.

Four 3d–4f heteromultinuclear zinc(II)–lanthanide(III) complexes constructed from a distinct hexadentate N2O2-type ligand: syntheses, structures and luminescence properties

Four 3d–4f heteronuclear complexes, [(ZnL)2La(OAc)2]·ClO4·2CHCl3 (1), [(ZnL)2La(OAc)2]·CF3SO3·H2O (2), [ZnNd(L)(Py)(NO3)3] (3), and [ZnGd(L)(OAc)(NO3)2] (4) (Py = pyridine; H2L = 6,6′-dimethoxy-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol), have been prepared by one-pot reaction of H2L with zinc(II) acetate, lanthanide(III) ions and Py. Although the heterobinuclear complexes 1–4 are prepared in the same reaction condition, the Py does not coordinate to Zn(II) of 1, 2, and 4. Instead, the bridging μ-acetato ligand is present. The coordination of the Py in 3 leads to smaller distortion of square pyramidal coordination site of Zn(II), the higher coplanarity between the planes of ZnO(phenoxo)2 and LnO(phenoxo)2, and the longer Zn⋯Ln distance compared with 4. The luminescence properties of 1–4 have been discussed. The ligand (L2−) can sensitize NIR luminescence of Nd(III) ions.

Enhanced 1.06 μm emission in Nd3+-doped lead-tellurite glasses doped with silver nanoparticles

Increasing the emission cross section of rare earth (RE) ions-doped transparent oxide glasses is a challenging issue. The incorporation of the metal nanoparticles (NPs) has been proposed as a promising approach to improve the emission properties, though the mechanism behind such a phenomenon is a controversial topic. Tellurite glass doped with Nd 3+ ions and silver NPs is prepared and the optical absorption and emission properties are studied. The surface plasmon band of the silver NPs is observed at around 522 nm. Absorption and excitation bands of the Nd 3+ ions are detected in the visible spectral region and associated to the transitions from ground state to various excited states. Threefold enhancement in the 1.06 μ m luminescence of Nd 3+ ions is observed under 800-nm laser excitation by incorporation of AgNO 3 up to 1 mol. %. Probable energy transfer and local field enhancements are discussed to explain the possible interactions between metal and RE ions.

Near-infrared luminescence of Nd3+and Yb3+complexes using a polyfluorinated pyrene-based β-diketonate ligand

Highly efficient near-infrared emitting Nd3+and Yb3+complexes have been developed based on a new polyfluorinated pyrene-appended β-diketonate ligand.