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Photochromic luminescent glass-ceramics attract lots of attention as an optical storage medium owing to their large storage capacity, reversible luminescence modulation, simple operation, etc. Herein, a kind of phosphosilicate glass containing AgBr nanoparticles was designed and prepared, which can realize the color reversible transformation between light yellowish-green and brown by alternating 365 nm light illumination and thermal treatment at 300 °C. The mechanism of photochromism and bleaching of the glass is related to the generation and decomposition of Ag0 clusters. Relying on the re-absorption effect, the emission intensity of Eu3+ ions could be reversibly regulated, showing the maximum luminescence contrast of 74 %. A good fatigue resistance and reproducibility of transmittance and luminescence modulation could be observed in cycle measurements, demonstrating its potential in the optical memory field. [ABSTRACT FROM AUTHOR]

[Display omitted] Treatment of 1,4-diazabutadienes (DADs) of formula DippN=C(R)C(R)=NDipp (Dipp = 2,6-Pr 2 iC 6 H 3 , R = H or Me) with 2 or 1 equiv. of potassium metal in THF leads to the corresponding dianions (DAD2–) or radical anions (DAD•−), respectively. The subsequent salt metathesis between LnCl3 (Ln = Tb or Er) and the above dianions affords dimeric monochlorido complexes [(DAD2–)Ln(THF) 2 (μ-Cl)] 2 with bridging chlorine atoms between the lanthanides. The reaction of the radical anion species with LnCl3, if R = H, gives monomeric dichlorido complexes (DAD•−)Ln(THF) 2 Cl 2 ; however, if R = Me, the activation of one methyl group occurs, which in the reaction with TbCl3 leads to the formation of a product with shifted double bonds [DippN=C(Me)C(=CH 2)N(Dipp)]Tb(THF) 2 Cl 2. [ABSTRACT FROM AUTHOR]

Low-dimensional all-inorganic metal halide perovskites (MHPs) have attracted attention due to their promising advantages as semiconductor materials for optoelectronic applications. However, obtaining a low-dimensional MHPs pure phase has been difficult due to its high ionic nature. Here, the one-step in-situ deposition of CsPb 2 Cl 5 films by Aerosol Assisted Chemical Vapor Deposition (AACVD) is reported for the first time. An analysis of the effects of precursor concentrations, using ethanol (EtOH) as antisolvent, and Yb3+ doping on the resulting three-dimensional and/or two-dimensional perovskite phase films is presented. It was found that a lead rich precursor (PbCl 2 :CsCl = 2:1) was necessary to promote the formation of the CsPb 2 Cl 5 phase, in addition, the use of EtOH and doping with hetero-valent Yb3+ ions was required to attain this phase successfully. The excitation and emission photoluminescence spectra analysis for these films is focused on the three principal emissions: i) a narrow emission peak around 418 nm from the CsPbCl 3 phase, ii) a dual broad emission around 550 nm from the CsPb 2 Cl 5 phase, and iii) an emission at 984 nm associated with the Yb3+ ions introduced as dopants in the MHPs lattice. A possible mechanism is proposed for the observed energy transfer from the CsPb 2 Cl 5 matrix to the ytterbium ions and for the interactions between Yb3+ and the excitonic emissions. [ABSTRACT FROM AUTHOR]

We report the analysis of Europium (Eu3+) ion-doped NaYF 4 thin films from an experimental and theoretical complementary point of view. The pristine and Eu3+ doped-NaYF 4 thin films were obtained by electrochemical deposition in the cubic phase (α-NaYF 4), which were fully characterized by X-ray diffraction, scanning electron microscopy, and photoluminescence techniques. The emission spectrum of α-NaYF 4 :Eu3+ exhibits two intense bands at 610 and 628 nm for 5D 0 → 7F 2 transition with an excitation energy source at 245 nm. The experimental emission spectrum of α-NaYF 4 :Eu3+ thin films suggests that the D 4h could be the local point symmetry around Eu3+ because of the number of sublevels in 5D 0 → 7F 1,2 transitions. The LUMPAC software was used to calculate the excited states, Judd-Ofelt (J-O) parameters, and energy transfer rates (ETR) from ligand to Eu3+ semi-empirically, using the local point group symmetry proposed in this work. The obtained J-O parameters are Ω 2 = 15.39 × 10−20 cm2, Ω 4 = 2.14 × 10−20 cm2, and Ω 6 = 0.1275 × 10−20 cm2, where Ω 6 was calculated by the QDC method despite of 5D 0 →7F 6 transition is not observed in the experimental emission spectrum. The calculated energy transfer rates give the energy transitions from ligand S 1 →T (singlet→triplet) to T→Eu3+. Finally, the analysis of molecular orbitals derived from time dependent-DFT calculations confirms that the electronic transfer occurs from F− → Eu3+ (from ligand to Eu3+). [ABSTRACT FROM AUTHOR]

Materials doped with the luminescent Eu3+ ion are attracting an ever-increasing amount of attention due to their potential applications in solid-state lighting, display devices, solar cells, or bioanalytics. But, why Eu3+? Unlike other lanthanides, its electronic features make the calculation of some physicochemical parameters quite straightforward, since they can be extracted directly from the emission spectrum. Highly appreciated for its reddish emission, the luminescent ion has also been widely used as a site-sensitive structural probe. With this in mind, this paper aims to offer easy guidance with helpful advice on how to interpret measurements of the emission spectra. It also presents the most useful tools for saving time, and gives a focused and practical explanation of the theoretical concepts involved. [Display omitted] [ABSTRACT FROM AUTHOR]

Luminescent CeF 3 and CeF 3 :Tb3+ nanoparticles (NPs) were synthesized by citric acid-supported wet chemical method at a lower temperature. X-ray diffraction (XRD) pattern was recorded to examine the crystal structure, particle size, and phase pureness of the nano-products. The shape and size of the as-synthesized nanoproduct were reviewed by transmission electron microscopy (TEM). The development of a hexagonal phase solid solution at the nanoscale by the successful incorporation of Tb3+ ion into the CeF 3 crystal lattice was confirmed by the XRD data. The solid solutions of nanocrystalline CeF 3 :Tb3+ NPs were confirmed by the TEM micrographs. Highly aqueous dispersible, agglomerated, typical porous surface, irregularly spherical shaped, well distributed polycrystalline particles were observed in TEM photographs. The development of a partially transparent colloidal solution with good colloidal stability in the aqueous media was indicated by the examination of optical characteristics. Based on absorption spectral analyses, the occurrence of structural imperfections and their impact on the bandgap energy was explored. The photoluminescence spectrum of the CeF 3 :Tb NPs was measured to authenticate the successful insertion of Tb3+-ion into the CeF 3 crystal matrix. CeF 3 :Tb NPs exhibit a prominent green color due to a dominant magnetic-dipole (5D 4 →7F 5) emission transition that is visible in the middle of the spectrum at 543 nm on irradiation from a UV light source. The sharp excitation and intense emission transitions astounding luminescence efficiencies indicated that the luminescent NPs are very crystalline. The as-prepared CeF 3 :Tb NPs have prospective uses in laser-based biological events including fingermark detection, security ink, and bio-tagging agents due to their superior luminescent and optical properties. [ABSTRACT FROM AUTHOR]

Ni/LnO x -type catalysts (Ln = La, Ce, Sm or Pr, denoted as LNO, CNO, SNO and PNO, respectively) were prepared via a citrate sol-gel method, characterized, and evaluated for the dry reforming of biogas. For the calcined catalysts, the formation of LaNiO 3 perovskite crystallites with high purity was observed in the case of La, whereas NiO-LnO x mixed oxides were obtained for the other lanthanides. The reduction treatment led to the formation of medium-sized (∼15 nm) and highly dispersed Ni nanoparticles in LNO following the decomposition of the LaNiO 3 perovskite, in contrast to the other catalysts, where bigger Ni crystallites were formed (∼30 nm). As a result, LNO was shown to possess a higher catalytic activity in comparison to the other materials. Regarding the catalytic stability, LNO displayed a considerable activity loss followed by a high pressure drop due to reactor blockage, meaning that the use of Sm (Ni/Sm 2 O 3) can be considered as an alternative strategy to restrict catalyst deactivation. As evidenced by the characterization of the spent catalysts, the deactivation for the most part can be attributed to the extensive coke deposition over the catalysts. The coke deposited was found to be both in the form of more disordered/amorphous carbon, as well as in the form of highly crystalline and multi-walled carbon nanotubes. • Ni/LnO x catalysts (Ln = La, Ce, Sm or Pr) were tested for biogas dry reforming. • LaNiO 3 was formed for La and segregated NiO-LnO x for the other lanthanides. • Decomposition of LaNiO 3 perovskite led to smaller Ni nanoparticles. • LNO presented improved activity but high activation energy and reduced stability. • Deactivation observed due to amorphous and crystalline coke formation. [ABSTRACT FROM AUTHOR]

(1- x)Ba 0.65 Bi 0.07 Sr 0.245 TiO 3 - x R 2 O 3 (BBST- x R) ceramics embellished by lanthanides (La, Yb, Gd) were synthesized in this study, and the effects in properties were ascertained. The results show that lanthanides with smaller ionic radius differences and larger relative mass will effectively limit mass transport of other cations and restrain grain growth. It is also found that the paraelectric phase of ceramics can be stabilized by decreasing the ionic radius of lanthanides. In particular, the addition of La unfolds the exceptional recoverable storage density (W rec) up to 2.23 J/cm3 and efficiency (η) of ∼76.7% under 280 kV/cm. Finite element simulation and PFM observation also further explain the reasons for the excellent performance. Concurrently, BBST-0.015La ceramic exhibits outstanding thermostability from 30 °C to 150 °C and frequency stabilization from 1 Hz to 300 Hz which indicates the potentiality of application in actual surroundings. [ABSTRACT FROM AUTHOR]

Due to the high cation exchange capacity, depressed permeability, low cost, and massive specific surface area, bentonite has crucial importance in the disposal of radioactive waste from their aqueous solutions. Here, the intercalation of 8-hydroxyquinoline onto the surface of Na-bentonite was carried out and the obtained material was used to explore the sorption conduct of lanthanides metal ions from their solutions. X-ray fluorescence, X-ray powder diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy spectra were done to characterize unmodified and modified bentonite. The changes in the environmental parameters such as contact time, solution pH, sorbent mass, initial concentration, and temperature were optimized. Sorption isotherm was simulated by Langmuir and Freundlich equations and the outcomes revealed that the Langmuir model was appropriate for the sorption of lanthanides onto 8-hydroxyquinoline bentonite (HQ-bentonite) and the maximum sorption capacities values were found to be 26.1, 47.6, 32.6, 39.2, and 40.9 mg/g for Y3+, Nd3+, Gd3+, Sm3+, and Lu3+, respectively, at 303 K. On the other hand, the regeneration studies were investigated with various reagents. [ABSTRACT FROM AUTHOR]

Rare earth elements (REEs) have been increasingly exploited for crucial new technologies, and their massive use in the past decades has significantly increased their environmental concentrations. In this article, we have tried to answer the question as to whether or not the wide use of REEs, including nanoparticles, in agriculture and medicine may pose a health risk to the population through diet. For this reason, information on their biological role and potential toxicity to living organisms has been summarised. The fate of REEs in the aquatic and terrestrial environment, such as surface water, soil, soil-plant systems and animals, was described. Particular emphasis was placed on their uptake by plants and animals, translocation between species and thus their entrance into the human food chain. For a better understanding of REEs bioavailability and toxicity, their physicochemical properties, such as e.g. solubility, oxidation state, chemical form, and coordination with ligands are discussed. Data on the estimated daily intake and the presence of REEs in the human body were also compiled. In our concluding remarks we identified gaps in knowledge about the impact of REEs on the population through diet and predicted future research needs in this area. [ABSTRACT FROM AUTHOR]

Advanced used nuclear fuel (UNF) reprocessing strategies are limited by the complex radiochemical separations and engineering required to achieve the separation of actinides (An) from neutron scavenging lanthanides (Ln). The accessibility of the hexavalent oxidation state for the actinides (U – Am) provides a pathway to achieving a group hexavalent actinide separation from the trivalent lanthanides and Cm. The solid oxidant and ion exchanger, sodium bismuthate (NaBiO 3), has been demonstrated to quantitatively oxidize and separate Am from trivalent Cm in a column chromatographic system. This work expands on the use of NaBiO 3 chromatography to characterize the adsorption, kinetic, and elution behavior of U, Pu, and Eu. Separation factors over 200 with rapid kinetics were observed at dilute nitric acid concentrations with a complete An/Ln separation achieved in under an hour. The adsorption and chromatographic behavior of key fission products present in various reprocessing raffinates was characterized which demonstrated potential application of a NaBiO 3 -based separation following a TRUEX process. [ABSTRACT FROM AUTHOR]

Four novel mononuclear lanthanide complexes, [Ln(TPymT)(NO 3) 3 (H 2 O) 2 ] (Ln: Eu3+ (1), Gd3+ (2), Tb3+ (3) and Dy3+ (4)), have been solvothermally synthesized using multidentate 2,4,6-tris(2-pyrimidyl)-1,3,5-triazine (TPymT). Compounds 1 – 3 have been characterized by means of elemental analysis, FT-IR, and single-crystal/powder X-ray diffraction analysis. Compound 4 was structurally characterized. The Ln3+ ion in 1 – 4 is ten-coordinated, where TPymT serves as an N 3 donor in an isostructural series. The alternating-current magnetic studies showed frequency dependence below ca. 10 K for 3 , as an indication of a single-ion magnet. The activation energy for the magnetization reorientation was estimated as U eff / k B = 95(9) K after applying a dc bias field 2000 Oe for 3. The photoluminescent studies clarified that 1 and 3 behaved as red and green light emitters with quantum yields as high as 17 and 39 %, respectively. The TD-DFT calculation supports the energy level scheme of ground and excited states of TPymT together with the reference compound 4′-phenyl-2,2':6′,2″-terpyridine. The present work suggests a broad chance and motivation to apply TPymT to the field of 4f coordination chemistry. [Display omitted] • Four novel mononuclear lanthanide complexes, [Ln(TPymT)(NO 3) 3 (H 2 O) 2 ] (Ln: Eu3+ (1), Gd3+ (2), Tb3+ (3) and Dy3+ (4)), have been solvothermally synthesized. • The alternating-current magnetic studies showed frequency dependence below ca. 10 K for 3 , as an indication of a single-ion magnet. • The photoluminescent studies clarified that 1 and 3 behaved as red and green light emitters with quantum yields as high as 17 and 39 %, respectively. • The TD-DFT calculation supports the energy level scheme of ground and excited states of TPymT together with the reference compound 4′-phenyl-2,2':6′,2″-terpyridine. [ABSTRACT FROM AUTHOR]

• The average REE concentrations of topsoils and profile soils are in decreasing order: Ce > La > Nd > Pr > Sm > Gd > Dy > Er > Yb > Eu > Tb > Ho > Tm > Lu. • The soils in southern Konya are enriched in LREEs and relatively depleted in HREEs indicating that LREEs are more mobile than HREEs during weathering processes. • REE contents in soils vary according to different geological units and decrease in the following order: volcanic > sedimentary > ophiolitic. • The soils have slightly negative Ce anomaly and positive Eu anomaly, which are consistent with those of the parental rocks. • EF and Igeo contamination parameters mostly indicate non-enriched soils. • The distribution patterns and spatial distributions of REEs in soils and bedrocks are similar. • REEs in soils vary significantly depending on bedrock types and originates from geological parent materials. The distribution of rare earth elements (REEs) was investigated in topsoils, soil profiles, bedrocks, and stream sediments collected from different geological environments in southern Konya to understand how natural and anthropogenic factors affect the geochemical behavior of REEs and the dynamics of pedogenic processes. The highest REE concentrations were observed in volcanic rocks and the lowest REE concentrations were observed in sedimentary rocks. The soils derived from volcanic rocks show the highest average REE content, followed by soils derived from sedimentary rocks and then soils derived from ophiolitic rocks. REE contents in soils derived from different geological units decrease in the following order: volcanic > sedimentary > ophiolitic. The average REE concentrations of soils in the study area are in decreasing order: Ce > La > Nd > Pr > Sm > Gd > Dy > Er > Yb > Eu > Tb > Ho > Tm > Lu. (La/Yb) N ranged from 1.19 to 1.86 with an average value of 1.5 indicating considerable enrichment of LREEs in topsoil. The highest LREE/HREE fractionation was determined in the soils over sedimentary rocks. The soils have slightly negative Ce anomaly (Ce/Ce*= 0.98 to 0.99) and positive Eu anomaly (Eu/Eu* = 1.02 to 1.12). REEs in the soil profile developed on sedimentary rocks (Profile-I; HPPR) were higher than those developed on ophiolitic rocks (Profile-II; KHPR). The soil profile samples show slightly negative Ce anomalies (Profile I=0.93, Profile II=0.93) and positive Eu anomalies (Profile I=1.08, Profile II=1.39) similar to topsoils. The spatial distribution of REEs normalized to the Upper crust and Earth crust showed that parental materials control the prevalence of REEs in soils of southern Konya. The distribution of REEs with Eu and Ce anomalies in the soils is similar to REEs with Eu and Ce anomalies in the parental rocks. The spatial distribution of REEs in soils appears to be controlled by the lithology of the study area as well as mineral composition, weathering process, and pH. Enrichment factors (EF) and geoaccumulation index (Igeo) commonly indicating non-enriched soils correspond to natural materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Comprehensive CB[n] Chemistry Review: Synthesis, interactions, complex formation, applications, and future research directions. The cucurbit[ n ]uril (CB[ n ]s) macrocycles have been generating tremendous interest in the supramolecular chemistry since last three decades. CB[ n ]s are not only able to include different guests, but are also capable of coordinating to a wide range of metal ions. When the reader takes a deep look through this review; he will find full details of CB[ n ]s synthetizations, preparation procedures and detailed separation methods from each other, beside their physical proprieties, where; [n = 5,6,7,8 and 10]. Also, the reader will find more details and discussion of their ability to coordinate with wide range of the periodic table element cations including; alkali, alkali earth, transition metals, lanthanides and actinides as well. In which, a detailed discussion of their bowl-like capsules complexes, molecular capsules complexes, and simple based coordination polymers with the formation of some of their supramolecular frameworks through hydrogen bonding, ion–dipole interaction, π...π stacking, and outer surface interaction. Finally, multiple applications of these CB[ n ]-based coordination polymers and their supramolecular have been mentioned and discussed with various examples including; separation of different gases and elements, beside the elimination of other cations, and capturing of dyes and other similar applications. [ABSTRACT FROM AUTHOR]

With the rapid development of information technology, people's security awareness of information protection is enhanced, and the requirements for anti-counterfeiting technology have become higher and higher on different occasions. Smart materials with light stimulus response have attracted extensive attention in the development of anti-counterfeiting materials, especially next-generation intelligent transparent wood. Inspired by the color-changing behavior of plants and animals in nature, a photochromic transparent wood (PTW) composite with light-stimulated response was prepared by compounding rare earth luminescent complexes with transparent wood (TW). PTW exhibits high transmittance (85.5 %). Moreover, PTW exhibits different optical states under different light conditions, namely, colorless under sunlight and bright red fluorescence under 365-nm UV light, and the process is reversible. Additionally, PTW patterned by laser etching offered greater flexibility and personalization in terms of stimulus-response, and its information security under different light stimuli is demonstrated. Meanwhile, the PTW prepared can be applied to different products and their packaging as an invisible anti-counterfeiting label, and the storage and protection of information is realized under visible light, and the decoding of information is implemented in UV light, so as to achieve the invisible anti-counterfeiting of information. More importantly, invisible information can be clearly identified even in black packaging. The design concepts and techniques of this study provide an inspiration to combine smart responsive materials with wood-based materials to develop intelligent responsive materials, and also provides support for the subsequent design and preparation of invisible anti-counterfeiting materials. [Display omitted] • Stimulus-responsive smart wood with photochromism was prepared. • Photochromic transparent wood has reversible and stable fluorescence performance. • Photochromic transparent wood exhibits good clipability and easy patterning design. • Photochromic transparent wood changes from colorless in sunlight to red in UV. • Photochromic transparent wood can be applied in invisible anti-counterfeiting. [ABSTRACT FROM AUTHOR]

• Ln-mediated dehydrogenation of ethylamine where Ln = La and Ce. • Vibrationally resolved ionization spectra and precise adiabatic ionization energies of Ln(NCH 2 CH 3). • Spin-orbit coupling of Ce(NCH 2 CH 3). • Plausible reaction pathways for the formation of Ln(NCH 2 CH 3). Ln (Ln = La and Ce) atom reactions with ethylamine are conducted in a pulsed laser vaporization supersonic molecular beam source. Dehydrogenation and association metal-containing species are observed with time-of-flight mass spectrometry, and the dehydrogenated Ln ethylimido species in the formula Ln(NC 2 H 5) are characterized by single-photon mass-analyzed threshold ionization (MATI) spectroscopy and quantum chemical calculations. The theoretical calculations include density functional theory for both Ln species and a scalar relativity correction, electron correlation, and spin-orbit coupling through multiconfiguration quasi-degenerate second-order perturbation theory for the Ce species. The MATI spectrum of lanthanum ethylimido La(NCH 2 CH 3) has a single vibronic band system from the ionization of the doublet ground state with the La 6s1 configuration, whereas that of the cerium ethylimido Ce(NCH 2 CH 3) displays two vibronic band system from the ionization of the two lowest-energy spin-orbit coupling states with the Ce 4f16s1 configuration. Both Ln ethylimido complexes are formed by the thermodynamically and kinetically favorable concerted dehydrogenation of the amino group. Two additional isomers of Ln(NC 2 H 5) include a four-membered metallacycle Ln(NHCH 2 CH 2) from the dehydrogenation of the amino and methyl groups and a three-membered cycle Ln(NHCHCH 3) from the dehydrogenation of the amino and methylene groups. The cyclic isomers are not observed experimentally as they are not populated under the experimental conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

Electrochemical energy storage has garnered significant attention from the scientific community and energy stakeholders due to its prospective applications, including e-vehicles. The present work aims to improve charge-storage device performance through the use of the novel semiconductor chalcogenide BaS:MnS:DyS, which is synthesized by chelating with diethyldithiocarbamate ligand. Remarkable photo-activity was detected for this semiconductor with an energy band gap of 3.59 eV. With mixed crystalline phases, the generated chalcogenide had an average crystallite size of 18.73 nm, exhibiting auspicious crystallinity. Furthermore, infrared spectroscopy was used to identify metallic sulfide connections, which were found to range between 400 and 967 cm−1. Double step thermal decomposition was confirmed by thermogravimetric analysis. A greater volume-surface area ratio and the existence of many sites were suggested by particles with varying shapes and a fusion resembling rod. With a background electrolyte of 1 M KOH, a conventional three-electrode setup was used to assess the BaS:MnS:DyS electrochemical performance. With a specific power density of 10826.7 W kg−1 and a specific capacitance of up to 824.13 F g−1, BaS:MnS:DyS is an excellent electrode material for energy storage applications. This noteworthy electrochemical performance was further substantiated by the similar series resistance (R s) = 0.77 Ω. [Display omitted] • Band gap tune trichalcogenide BaS:MnS:DyS. • Profound aspects as energy material. • BaS:MnS:DyS adorned nickel foam electrode. • Charge storage of 824.13 F g−1 specific capacitance. • Specific power density of 10826.7 W kg−1 [ABSTRACT FROM AUTHOR]

[Display omitted] • Gd and Tm can replace Sm in 1,10-phenanthroline complexes. • Functionalization in C5/C6 improves electronic properties of complexes. • Lanthanides-1,10-phenanthroline complexes can work via LMCT mechanism. • Lanthanides-1,10-phenanthroline complexes can be adopted for photo-induced therapies. In the present work, outcomes from a density functional theory investigation on the effect of lanthanides (Lns)-containing 1,10 phenanthroline complexes are discussed. Starting from the recently synthetized [Sm(L1) 3 ]3+ (L1 = 1,10 phenanthroline), the effect of metal center replacement and of functionalization in position C5 and C6 of the ligand is examined. In detail, the comparative analysis of electronic and structural properties proceeds testing the presence of Gd3+ and Tm3+ instead of Sm3+, in combination with 1,10 phenanthroline-5,6 dione (L2), 5,6 dimethyl 1,10 phenanthroline (L3) and 1,10 phenatroline-5,6 diamine (L4) ligands. From deeper analysis, it turns out that the lanthanides do not affect the geometrical structure of the complexes, since slight variations of metal–ligand distances are observed. On the other hand, combination of ligands and metals lead to an improvement of the calculated electronic absorption for all the compounds with respect to the available experimental data, linked to the different nature of the frontier orbitals. In particular, for all complexes expected [Gd(L1) 3 ]3+ a near-IR absorption is observed and discussed, thus opening to the possible adoption of such complexes for future photoinduced medical applications. [ABSTRACT FROM AUTHOR]

• Transamidation is the key reaction in organic synthesis. • Metal-Catalysed transamidation of unactivated amides. • Various transition and non-transition metals have been used as catalyst. Amides played a vital role in the development of organic synthesis in recent years. These structural motifs are found in several biologically important synthetic and naturally occurring compounds. Developing efficient methods for their synthesis is crucial for drug discovery. Transamidation is a prominent tool in organic and medicinal chemistry, enabling the replacement of the amine group in an existing amide with new functionalised amines. Additionally, Transamidation process is used significantly in the total synthesis of few naturally occurring compounds. Transamidation reaction has been achieved significantly by using metal catalysis but there are several metal-free approaches have been employed to achieve the same reaction. This review focuses on recent literature concerning metal-catalysed transamidation reactions, highlighting the use of alkaline earth metals, transition metals, lanthanides, actinides, alkali metal salts or complexes, and metalloids. Both catalytic and stoichiometric quantities of catalysts are discussed for their roles in enhancing reaction efficiency. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • An iodinated phthalocyanine photosensitizer with a nonlinear response was obtained. • Synthetic procedure to 4,5-diiodophthalonitrile was modified. • A good ability to generate singlet oxygen was observed for iodinated phthalocyanine. • Competition between two photoreactions was demonstrated. • The presence of a "heavy" iodine atom enhances the nonlinear optical response. New octaiodo-substituted lutetium (III) phthalocyanine was prepared using a six-step synthetic procedure starting from commercially available o -xylene. The amide synthesis and dehydration step were optimized. The influence of the nature of peripheral halogen atoms on optical and photochemical properties was studied. For the complex under study, the possibility of participation in photoreactions of types I and II with the formation of two different forms of reactive oxygen species was investigated: superoxide anion radical and singlet oxygen respectively. Competition between two photoreactions was demonstrated. The Z-scan method revealed a pronounced nonlinear optical response of the iodinated complex, caused by the action of heavy atoms of peripheral iodine groups. [ABSTRACT FROM AUTHOR]

• Impact of coordinating & non-coordinating materials on morphology of Ln3+ NPs. • Influence of the pH on shape and size of the UCNPs. • Surface functionalization materials and their role in colloidal stability. • Future perspectives in expansion of surface engineering materials. The efficient utilization of the photosensitive rare-earth (RE3+/Ln3+) NPs in several fields, such as biosensing, biomarkers, bioimaging, theragnostic, thermometry, anticounterfeiting, fingermark detection, environmental monitoring, photocatalysis, security ink, emitting diodes, and dye-sensitized solar energy, is depending upon their design. In order to get more efficient luminescent Ln3+-NPs controlled morphology and size are the most significant factors. In this review, we summarized a wide-ranging exploration of the polymeric materials, surfactants, capping agents, ligands/chelating/complexing agents employed as a surfactant to control the growth of nucleus, surface functionality, colloidal dispersibility in polar and nonpolar media. The functionality and colloidal persistence of the nanostructures are highly dependent on the surfactant selection, whereas the morphology and dimension of the core Ln3+ NPs determine its photophysical characteristics. Surface-attached organic moieties either polymeric materials, coating agents, or ligands not only facilitate in controlling analogous shape & size but also assist in aqueous or non-aqueous dispersibility, biocompatibility, hydrodynamically of the as-prepared Ln3+ NPs. However, surfaces covered with organic or high vibrational functional groups/molecules are the main drawback in suppressing the emission efficiency of the Ln3+-NPs. Therefore, before the synthesis of the luminescent Ln3+-NPs selection of the chelating ligands or long-chain hydrocarbons/surfactants is important to control these two contradictory features of the luminescent Ln3+-NPs for efficient use in clinical sciences. Additionally, it concludes with an overview of recent progress in surfactants, long alkyl chain hydrocarbons, chelating ligands, and coating agents highlighting their significance in upcoming prospects and trials in advancing the field. The burgeoning progress of active luminescent Ln3+ nanostructures paves the way for their application in therapeutic, biotechnological, and materials science research, charting new paths for future exploration. [ABSTRACT FROM AUTHOR]

The human elementome, the number and amounts of elements used biologically and nonbiologically by humans, has increasingly diverged from the biological elementome that characterizes the elements used by the nonhuman living organisms. This increasing divergence due to human cultural evolution has huge ecological, evolutionary, environmental, and geopolitical consequences. [ABSTRACT FROM AUTHOR]

[Display omitted] • Lanthanide exhibit long PL lifetimes, facilitating time-resolved applications. • Water-stable lanthanide luminophores are scarce. • Despite water quenching, PAnt dynamically coordinates with Tb(III) and Eu(III) • Spectroscopy and TD–DFT unveil sensitization mechanisms for Eu(III) and Tb(III) Lanthanide photoluminescence (PL) emission has attracted much attention for technological and bioimaging applications because of its particularly interesting features, such as narrow emission bands and very long PL lifetimes. However, this emission process necessitates a preceding step of energy transfer from suitable antennas. While biocompatible applications require luminophores that are stable in aqueous media, most lanthanide-based emitters are quenched by water molecules. Previously, we described a small luminophore, 8-methoxy-2-oxo-1,2,4,5-tetrahydrocyclopenta[ de ]quinoline-3-phosphonic acid (PAnt), which is capable of dynamically coordinating with Tb(III) and Eu(III), and its exchangeable behavior improved their performance in PL lifetime imaging microscopy (PLIM) compared with conventional lanthanide cryptate imaging agents. Herein, we report an in-depth photophysical and time-dependent density functional theory (TD–DFT) computational study that reveals different sensitization mechanisms for Eu(III) and Tb(III) in stable complexes formed in water. Understanding this unique behavior in aqueous media enables the exploration of different applications in bioimaging or novel emitting materials. [ABSTRACT FROM AUTHOR]

The analysis of the X-ray structures of rare-earth polyaminopolycarboxylate complexes provides information on the potential energy surfaces associated with N-C-C-X of five-membered chelate rings, as demonstrated with DFT studies. This combined analysis of experimental and computational data provides important information on the dynamics of rare-earth complexes leading to isomer interconversion. [Display omitted] • Puckering of five-membered chelate rings differs significantly depending on donor type. • N-C-C-X dihedrals display Gaussian distributions in the solid state. • DFT provides potential energy surfaces that afford force constants for the dihedral angles. • Widths of the Gaussian distributions correlate with quadratic force constants. • Cubic and quartic force constants are affected by environmental effects. In this study we take advantage of the large body of X-ray data reported for lanthanide complexes, as well as their similar coordination chemistry properties, to gain insight on the dynamic processes involving λ ↔ δ configurational changes leading to isomer interconversion. The analysis of X-ray data reveals that different donor groups are characterized by Gaussian distributions of the dihedral N–C–X–Y angles ϕ. In the case of ethylenediamine groups (X = C; Y = N) Gaussian distributions are very narrow, while acetates (X = C; Y = O) provide very broad distributions. The analysis of the potential energy surfaces (PESs) using DFT reveals that ethylenediamine groups are characterised by well-defined deep energy minima, while those of acetate groups are rather swallow. Other donor groups like acetamide, pyridine or phosphinate show intermediate Gaussian distributions with respect to ethylenediamine and acetates. The PESs were fitted to a potential incorporating quadratic, cubic and quartic terms. The quadratic force constants k 11 obtained for the different donor types follow the trend of the full width at half maxima (FWHM) of Gaussian distributions obtained from X-ray data. The k 11 values are very similar for a given donor group, while the anharmonic cubic (k 111) and quartic (k 1111) force constants vary significantly depending on the environment of the donor group. Overall, this work demonstrates that the analysis of X-ray crystallographic data in lanthanide complexes can provide very useful information on their coordination chemistry preferences and dynamic processes. [ABSTRACT FROM AUTHOR]

• Neodymium (Nd) purification using high-speed counter-current chromatography (HSCCC). • Initial Nd mass loading increased by two orders of magnitude, to the preparative scale. • Successful Nd purification from La, Ce and Sm at high REE loadings (15 mg). • Successful Nd purification from nearest neighbor Pr at low REE loadings (0.3 mg). • Solvent properties identified as being a significant factor in the ability to scale. Efficient rare earth element (REE) separations are becoming increasingly important to technologies ranging from renewable energy and high-performance magnets to applied radioisotope separations. These separations are made challenging by the extremely similar chemical and physical characteristics of the individual elements, which almost always occupy the 3+ oxidation state under ambient conditions. Herein, we discuss the development of a novel REE separation aimed at obtaining purified samples of neodymium (Nd) on a multi-milligram scale using high-speed counter-current chromatography (HSCCC). The method takes advantage of the subtle differences in ionic radii between neighboring REEs to tune elution rates in dilute acid through implementation of the di-(2-ethylhexyl)phosphoric acid (HDEHP)-infused stationary phase (SP) of the column. A La/Ce/Nd/Sm separation was demonstrated at a significantly higher metal loading than previously accomplished by HSCCC (15 mg, R Nd/REE > 0.85), while the Pr/Nd separation was achieved at lower metal loadings (0.3 mg, R Nd/Pr = 0.75 – 0.83). The challenges associated with scaling REE separations via HSCCC are presented and discussed within. [ABSTRACT FROM AUTHOR]

[Display omitted] • This work deal with study of the structure, keto-enol, spectral and chelation properties of three β-diketones with pyrrole, pyrazole, and pyridine rings. • The formation constants for the sixteen rare earth complexes, dissociation and protonation constants have been determined in an aqueous solution. • Quantum-chemical simulations were performed with using DFT and TD-DFT. Aqueous equilibria of three substituted perfluorinated 1,3-diketones with pyrrole, pyrazole, and pyridine rings have been extensively studied in aqueous solutions. Thermodynamic characteristics of dissociation, protonation, and chelation processes have been investigated by UV–Vis spectroscopy using non-linear regression analysis. Acid-base parameters were discovered in the acidity range from highly acidic media (C(HCl) = 10 M) to alkaline pH region. Dissociation constants (pK a) have been determined in glycine-HCl, phosphate-citrate, and TRIS-HCl buffered media. Protonation activities were studied by the Cox-Yates approach in concentrated hydrochloric acid solutions. First formation constants of ML complex species with trivalent ions of Sc3+, Y3+, La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+, Dy3+, Tb3+, Ho3+, Er3+, Tm3+, Yb3+, and Lu3+ have been obtained in the pH within 3.0–5.6 (I = 0.5 M, NaCl). True stability constants have been calculated using determined acid-base parameters considering side reactions. The "True" formation constants lie from 3.7 to 6.9 logarithmic units and have a linear relationship with the ionic (Coulomb) potential of metals. DFT and TD-DFT simulations have been performed for the modeling of the data obtained. [ABSTRACT FROM AUTHOR]

[Display omitted] • Electrolytic extraction of rare earths in LiCl-KCl molten salts by co-reduction is an order of magnitude higher than using an active cathode. • The method allows rapid extraction of 99.9 % of cerium in less than 4 h with an actual current efficiency of 97.8 %. The extraction of lanthanides in spent fuel reprocessing plays a key role in the development of nuclear energy. In this work, the extraction of the typical fissionable cerium elements has been studied by electrolytic co-reduction of Al(III) and Ce(III) in LiCl-KCl-CeCl 3 molten salts assisted by KAlCl 4. The electrochemical behavior of the reduction of Al(III) and Ce(III) on a molybdenum electrode was studied by cyclic voltammetry (CV), square wave voltammetry (SWV), and open circuit chronopotentiometry (OCP), and specific peaks of five Al-Ce intermetallic compounds were detected. After 2.7 h of galvanostatic electrolysis at a current density of 0.064 A cm-2, the extraction efficiency and current efficiency of Ce(III) reached 99.9 % and 91.3 % respectively. Potentiostatic electrolysis is slightly more efficient, with 99.9 % Ce(III) extraction in 3.5 h at a current efficiency of 97.8 %. The products of electrolysis are rod-shaped alloys (Al 11 Ce 3 , Al 3 Ce, Al 2 Ce), and the molten salts purified by electrolytic separation are free of impurity signals and can be reused for electrolytic refining. [ABSTRACT FROM AUTHOR]

[Display omitted] • IDA greatly enhances the electrophoretic separation of four lanthanides (La, Sm, Dy, and Lu) when used as an on-capillary complexing ligand. • Enhanced separation is due to IDA's preferential coordination between light and heavy lanthanides. • Molecular dynamics simulations validate the predicted metal-ligand conformations with IDA and light/heavy lanthanides. Rare earth elements (REEs) are a class of critical materials vital to an array of applications such as electronics, batteries, and defense weapons systems. These elements coexist in minerals and ores, and due to their similar chemical properties, the challenge remains to find an effective means of separation. Current large-scale separation processes rely on slight differences in size and acidity between REEs, however these separations are inefficient and pose detrimental risks to the environment due to the large volumes of volatile organics and acids required to achieve separations. REEs can be separated on the basis of their migration under an applied electric field, i.e., their electrophoretic mobility, which depends on differences in size and charge and may be modified through coordination with ligands. The degree to which coordination with ligands may influence the transport properties of these metal-ligand systems remains, for the most part, unknown. Here, we investigate the fundamental transport properties of a series of REE-carboxylate ligand complexes in aqueous solution via capillary electrophoresis and molecular dynamics (MD) simulations are carried out to validate metal-ligand coordination geometry and diffusion properties. Iminodiacetic acid (IDA) is identified as a ligand that greatly enhances separation between light and heavy lanthanides by selectively coordinating with light lanthanides in a tridentate mode and heavy lanthanides in a bidentate mode. [ABSTRACT FROM AUTHOR]

Recent synchrotron X-ray studies have revealed a variety of specific ion effects in the structures formed by lanthanides and surfactants at air-water and solvent-water interfaces. However, the relevance of the interfacial structure to extraction and selective separation processes has been unclear. We have studied solvent extraction from aqueous solutions containing lanthanide ions to organic solvents containing model extractants, and correlated the results to the interfacial structure. The selectivity, extraction rates and extraction efficiencies are consistent with the postulate that when hydrophobic bilayers form at the interface, there is faster and better extraction. Further, selectivity during extraction from mixtures is enhanced when there is less extractant than needed for complete extraction of all the ions present. [Display omitted] [ABSTRACT FROM AUTHOR]

The Eu3+-betadiketonate coordination compounds are intensively studied due to their intense photoluminescence, which places them as promising materials with different applications, such as ammunition markers, biological sensors, and mainly as electroluminescent materials in Organic Light Emitting Diodes (OLEDs). This work reports the synthesis, thermal and kinetic study, crystal structures, experimental and theoretical photoluminescence analysis of two new Eu3+-betadiketonates of general formula [Eu(tta) 3 (5,5′-dmbpy)] 1 and [Eu(btfa) 3 (5,5′-dmbpy)] 2 , where Htta = 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione, Hbtfa = 4,4,4-trifluoro-1-phenyl-1,3-butanedione and 5,5′-dmbpy = 5,5′-dimethyl-2,2′-bipyridine. Photoluminescence spectroscopy data revealed that the compounds can be sensitized directly by the metal ion or through of the excitation of the excited states of the ligand system. Due to the high quantum efficiencies found for both complexes, they were used in the preparation of two OLED devices, with these devices exhibiting excellent efficiency and color purity, making them well-suited for organic electronic applications. • Two new Eu3+-betadiketonates have been synthesized and fully characterized. • Thermal and kinetic studies were performed for both compounds. • Photoluminescence studies show high quantum efficiencies for both complexes. • Two OLED devices with high luminance were constructed. • 4,4′-bis(N-carbazolyl)-1,1′-biphenyl was employed as a host material in these OLEDs. [ABSTRACT FROM AUTHOR]

The AlF 3 -MF 2 -LnF 3 (M = Ca; Sr; Ba; Ln = Yb/Tm) based pure fluoride GCs are essentially ideal candidates for the realization of PL in UV and VIS spectral region. However, the pure fluoride glasses are prone to precipitation of undesired nano-crystals while quenching and post annealing due to their poor chemical stability. Therefore, the development of such glass systems requires strict adherence to composition control right from the outset. This research employed extensive molecular dynamics (MD) simulations and incorporated the results into the experimental design to develop an efficient multicomponent fluoride glass system. Vivid simulation of M-F-Ln and M-F-Al nano-cluster formation via MD are observed in the glass matrix. These nano-clusters serve as the structural origins of the precipitated nano-crystals in GCs post heat treatment. Through meticulous manipulation of the Al/M ratio, it became feasible to theoretically forecast the transformation of the glass matrix from a cubic M 1-x Ln x F 2+x to a hexagonal Ln 1-y M y F 3-y nano-crystal precipitated GCs, which could conceivably be manufactured experimentally. This transformation offers superior luminescent performance for Ln 1-y M y F 3-y containing GCs enabling short-wavelength PL realisation in near UV (∼361 nm with 8-fold enhancement) and VIS (∼478 nm with 1.7-fold enhancement) from Yb3+/Tm3+ transitions, in comparison to its cubic M 1-x Ln x F 2+x counterpart. Hence, we propose an effective fluoride glass system for short-wavelength upconversion luminescent applications through the integration of MD simulations and experimental research. • MD simulated M-F-Ln clusters in glass can predict precipitation of Ln 1-y M y F 3-y. • Hexagonal Ln 1-y M y F 3-y nano-crystallization is accordingly experimentally fulfilled. • Ln 1-y M y F 3-y contained GCs get strong short wavelength upconversion luminescence. [ABSTRACT FROM AUTHOR]

Plant growth requires a complex network of arbuscular mycorrhizal (AM) fungi and bacteria to supply organic compounds and major (C, N, P, etc.) and trace nutrients to the roots. Hyperaccumulation by certain plant species is based on the threshold 'maxima' a plant can safely ingest/absorb an element from soils without tissue damage. The latter criteria for hyperaccumulation vary between elements. The amount of an element a plant can absorb depends both on the ability of the species to uptake the element and on the element concentrations and bioavailability in the substrate. A plant growing directly on a mineral-rich substrate or a short height above the soil should be able to access inorganic matter via the roots. In contrast, a plant capable of accumulating inorganic elements, but growing on a peat without direct root contact with the inorganic soil fraction, would suffer a dearth of mineral nutrients. Partitioning of elements occurs within hyperaccumulators. For example, the preferential binding of heavy rare earth elements (HREE) to organic ligands leads to the relative enrichment of HREE in aerial plant structures. The presence of hyperaccumulators in a wide range of present-day plant species suggests that this mechanism was present among peat-forming plants in the fossil record. Examples from peats through low-rank coals to high volatile A bituminous coals show that hyperaccumulation provides a viable hypothesis for the consequent enrichment of certain elements. Complications from the depositional history and diagenetic alteration of the peat; metamorphism and mineralization through the history of the coal; and, not the least, the problems implicit in sampling suitable intervals in working mines, cores, natural exposures, etc., present problems in the extrapolation of the modern plant mechanisms to coals. Coal represents natural settings and, apart from Miocene and younger coals produced from vegetation with known relatives in modern setting, we cannot experiment on the ancient plants. The analogies between the geochemical appearance of coals and the element uptake and partitioning behavior of modern plants, however, does offer hope that hyperaccumulation might have been a mechanism, potentially one of many mechanisms, for the organic associations of inorganic elements in coals. • Hyperaccumulation varies between elements and between plant species. • Certain plants are known to be accumulators of rare earths and other elements. • Partitioning of REE occurs in the transfer from the roots to shoots to leaves. • Low-rank and high volatile bituminous coals exhibit complex element associations. • Certain REE patterns in coals resemble those seen in translocations in modern plants. • Uncertainties in modern plants and coals comparisons are challenges in studies. [ABSTRACT FROM AUTHOR]

Optical thermometers based on lanthanide thermal-coupled levels have attracted great attention owing to its fundamental importance in the fields of public health, biology, and integrated circuit. However, the inherent structural properties (shielded effect on 4 f configurations, intense non-radiation relaxation) strictly suppress the sensing performance, limiting the relative temperature sensitivity (S R). To circumvent these limitations, we propose an intervalence charge transfer mashup strategy by inducing d 0 electron configured transition metals. Specifically, transition metals Ta5+ is incorporated in Tm3+/Eu3+:LiNbO 3 , which improves the S R from 5.30 to 11.16% K−1. The validity of this component-modulation behavior is observed on other oxide crystals (NaY(Mo 1-z W z O 4) 2) as well. Furthermore, the observed regulation is well explained by DFT calculation that indicates the d -orbit component at valence band minimum remains the core factor governing the electron transfer process. We successfully relate the S R to the band structure of luminescence carrier, offering a novel perspective for the collocation design of lanthanide configurations. [Display omitted] • The intervalence charge transfer states (IVCTs) mashup is proposed to circumvent inherent structural limitations of thermal-coupled levels (TCLs), wherein the electron transfer pathway between Tm3+(1D 2) and Eu3+(5D 0) states is optimized by inducing Ta5+ into Tm3+/Eu3+:LiNbO 3. • The relative temperature sensitivity is improved from 5.30 to 11.16% K−1 when the Ta5+ content increases up to 60 mol% (Tm3+/Eu3+:LiNb 0.4 Ta 0.6 O 3). • DFT calculation is applied to explained the component-dependence mechanism, and relates the relative temperature sensitivity to the band structure of luminescence carrier. • The universal validity of this IVCT-mashup mechanism is evidenced in in other oxide crystal doping with d 0 electron configured transition metal ions. [ABSTRACT FROM AUTHOR]

The stability constants of Sm3+, Ho3+ and Y3+ complexes with EDTMP have been determined by the combination of potentiometric and spectrophotometric methods. [Display omitted] • The stability constants of Sm3+, Ho3+ and Y3+ have been determined by the combination of potentiometric and spectrophotometric methods. • These data have been compared with the data given from the literature. • The discrepancy between the data of various authors has been solved. In connection with a study of 153Sm and 90Y complexes as potential radiopharmaceutical agents, the stability constants of those formed with EDTMP (ethylenediamine-N,N,Ń,Ń-tetra(methylenephosphonate)) were calculated using data from potentiometric and spectrophometric titrations measured at 25 °C in 0.1 mol/l NaCl. The following values were obtained for the stability constants of the Sm3+ − EDTMP complexes SmH -1 L6-, SmL5-, HSmL4-, H 2 SmL3-, H 3 SmL2- and H 4 SmL-: log β = 7.56, 19.08, 27.75, 34.76, 40.16 and 45.55 respectively. The corresponding stability constants of the Y3+ − EDTMP complexes YH -1 L6-, YL5-, HYL4-, H 2 YL3-, H 3 YL2- and H 4 YL- were log β = 10.47, 19.96, 28.13, 35.06, 40.35 and 46.13. A diagram of the complexes speciation dependence on pH shows that the complex forms HML4-and H 2 ML3- (M = Y or Sm) are characteristic of the pH range 6–8, which is suitable for application into the human body. [ABSTRACT FROM AUTHOR]

In this study, Co-based catalysts supported over Ti-Al oxide and promoted with La, Ce, Mg, and K metals were assessed for CO 2 reforming of methane reaction to produce syngas. Titania-alumina mixed oxide supports were prepared using the template-assisted-solvothermal method, and then Co and promotors were co-impregnated over the as-prepared support. Different characterizations of catalysts showed that variation in promotor metal impacts these catalysts' physical and chemical properties. The Ti-Al oxide support possessed the perfect hexagonal morphology. Potassium-promoted catalysts possessed the highest number of basic sites, whereas the La-promoted catalyst possessed the highest number of acidic sites. La promotion improved the Co dispersion, while Mg promotion enhanced the metal support integration. La-promoted catalysts are deactivated because of active metal oxidation and the generation of hard carbon. The carbon was deposited in all catalysts; however, the activity of the Mg-promoted catalyst was unaffected. The intermediate surface basicity and strong metal support interaction improved the Mg-promoted catalyst's stability. The La and Mg-promoted catalysts possessed lower apparent activation energies. • The effect of the La, Ce, Mg, and K promotion of Co/TiO 2 -Al 2 O 3 catalysts was examined for CO 2 reforming of methane. • The modified synthesis method produced the TiO 2 -Al 2 O 3 particles with hexagonal morphology. • The stability of various Co-X/TiO 2 -Al 2 O 3 follow an order of X = Mg > Ce > K > La. • Promoting the catalyst drastically changed the catalyst's physicochemical properties and DRM reaction dynamics. • The apparent activation energies for various doped catalysts follow the order of K > Ce > Mg > La. [ABSTRACT FROM AUTHOR]

The emergence of mining projects for rare earth elements (REEs) in response to rising global demand and geopolitical factors introduces environmental concerns, such as the suspected release of anthropogenic REEs to aquatic systems and the coexistence of radionuclides (U, Th). Northern regions confront heightened challenges from limited research and accelerated climate change. Drivers of REEs in surface waters (including George and Koroc rivers, their tributaries, and thermokarst lakes) were studied (2017–2023) in subarctic Canada within a climate transition zone, near a prospective REE mine. Dissolved REEs (<0.45 μ m) correlated positively with Al, Fe, Th, U, Cl– and DOC. A novel relationship with water temperature demonstrated an approximate 10-fold decrease in REE concentrations over the environmental gradient (2–20 ℃), suggesting complex implications for REE speciation under climate pressures. Optical analyses further predicted REEs were mobilized by humic-rich, terrestrial DOC, with correlations presenting a possible co-transport with Al, Fe and Th. Relationships for redox-sensitive Ce anomalies (Ce/Ce* = 0.18–1.2) with multi-valent trace metals (Al, Fe, Ti) and DOC were suggestive of a preferential adsorption of Ce by inorganic colloids in low-DOC systems. Findings emphasized the potential for changes in REE geochemistry with ongoing northern surface warming and vegetation shifts. [Display omitted] • First insights into REEs, U and Th in two subarctic river basins before REE mining. • Modelled field data predicted lower dissolved REEs with higher water temperatures. • REE distribution and Ce fractionation driven by colloidal Al, Fe and Ti. • Suspected co-transport of REEs, Th, Al and Fe with humic-rich terrestrial DOC. • Changes in DOM release to northern systems may alter aquatic REE geochemistry. [ABSTRACT FROM AUTHOR]

Nd3+,Y3+ codoped CaF 2 nanoparticles (NPs) have been synthesized by a microwave-assisted hydrothermal method, using citrate moiety as capping agent. Y3+ ions have been introduced in the crystal structure to declusterize the Nd3+ ions and improve the emission properties. After a structural and morphological characterization of the obtained NPs, the optical properties of colloidal dispersions have been analyzed in the near infrared (NIR) range. The emission spectra reveal several transitions associated with different sites where the Nd3+ ions are accommodated in the crystal structure. Some bands show a marked dependence on the temperature, and a thermometric investigation reveals good thermal relative sensitivities in the physiological temperature range (20–60 °C), proving the applicability of the investigated colloidal NPs as optical nanothermometers. • CaF 2 :Nd3+,Y3+ nanoparticles are prepared by a MW assisted hydrothermal method. • Water colloidal dispersions are very stable. • Optical thermometry is evaluated in the 1st and 2nd biological windows using Nd3+ emissions. • Very good relative thermal sensitivities are found. [ABSTRACT FROM AUTHOR]

The growing utilization of rare earth elements (REEs) in industrial and technological applications has captured global interest, leading to the development of high-performance technologies in medical diagnosis, agriculture, and other electronic industries. This accelerated utilization has also raised human exposure levels, resulting in both favourable and unfavourable impacts. However, the effects of REEs are dependent on their concentration and molecular species. Therefore, scientific interest has increased in investigating the molecular interactions of REEs with biomolecules. In this current review, particular attention was paid to the molecular mechanism of interactions of Lanthanum (La), Cerium (Ce), and Gadolinium (Gd) with biomolecules, and the biological consequences were broadly interpreted. The review involved gathering and evaluating a vast scientific collection which primarily focused on the impact associated with REEs, ranging from earlier reports to recent discoveries, including studies in human and animal models. Thus, understanding the molecular interactions of each element with biomolecules will be highly beneficial in elucidating the consequences of REEs accumulation in the living organisms. [Display omitted] • REEs pose a significant threat to both environment and living organisms. • Toxicity of REEs on organisms involves both synergistic and antagonistic effects. • Occupational exposure to REEs in human habitats is known to be more hazardous. [ABSTRACT FROM AUTHOR]

[Display omitted] • Valeric acid produced from levulinic acid in a single-step using formic acid as H 2 source. • Weak Lewis and strong Brønsted basic sites on Ni-La/TiO 2 surface was responsible for the high selectivity of valeric acid. • 99% selectivity of valeric acid was achieved using aqueous γ-valerolactone. • Surface metallic Ni in conjunction with surface acid-base sites were identified by N 2 O titration and in situ IR study. Titania supported Ni catalyst modified by different lanthanides (La, Ce, Pr and Nd) were evaluated for the one-step conversion of levulinic acid (LA) to valeric acid (VA) using formic acid as a hydrogen source. Among these, the La modified Ni/TiO 2 demonstrated better VA yields with an optimum LA to VA mole ratio of 1:3. Pyridine and/or formic acid adsorbed IR studies revealed that presence of weak Lewis and strong basic sites present on the Ni-La/TiO 2 surface was the reason for higher VA selectivity. The physicochemical characteristics of the modified Ni-M/TiO 2 (M = La, Ce, Pr and Nd) catalysts deduced from H 2 -TPR, N 2 O titration, TPD of NH 3 and catalytic activity data emphasized a combination of metallic Ni with surface acid-base sites were responsible for the formation of VA in single step. Using aqueous γ-valerolactone, 99 % selectivity towards VA was achieved. A plausible reaction mechanism has been proposed based on the kinetic data obtained at moderate temperatures and ambient pressures. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries, as one of the energy storage devices, has attracted much attention due to its remarkable characteristics. However, they pose safety challenges because of their liquid electrolytes. Solid electrolytes are one of the key candidates to tackle the safety issues in Li-ion batteries. As a solid electrolyte, garnet-type Li 7 La 3 Zr 2 O 12 is a promising candidate with its high stability against lithium metal and wide electrochemical window among its counterparts. But, the ionic conductivity is yet to be compared with liquid electrolytes. Hence, doping is still the common strategy to adjust the ionic conductivities. Despite the fact that doping with various elements is well-documented, Lanthanide group element doping is not thoroughly investigated. This research is to study the synthesis of garnet-type Li 7 La 3-x M x Zr 2 O 12 (M = Sm, Dy, Er, Yb; x = 0.0–1.0) novel compositions to enlighten the effect of lanthanide group element doping as a function of ionic radius. Results showed that increasing dopant ionic radius improves densification, diminishes Li-ion conduction and, except Yb case, expands the lattice. However, impurity phases formed when the solubility limit is reached, has overall a positive impact on Li-ion conduction. The highest ionic conductivity (0.15 mS/cm) and lowest activation energy (0.18 eV) without impurity phases were obtained from Yb doped LLZO. It was also found that the presence of LiDyO 2 improves the ionic conductivity to 0.16 mS/cm. [ABSTRACT FROM AUTHOR]

• Structural features of lanthanide coordination polymers are reviewed. • Crystal structures of lanthanide coordination polymers are provided. • Coordination environment of lanthanides is discussed. • The role of lanthanides in modulating the structural pattern is revealed. • Catalytic applications of lanthanide coordination polymers are highlighted. The review showcases the structural features of an array of recently reported lanthanide coordination polymers with catalytic properties. The field of lanthanide coordination polymers has considerably progressed during the last decade placing it at the forefront of the materials science. The wealth of obtained data clearly demonstrates that lanthanides play a determinant role in tailoring the structural pattern, coordination environment, dimensional configuration and network architecture of coordination polymers. As a rule, the lanthanide(III) ions possess a high coordination number and a large atomic radius, and because of that they tend to generate highly connected complex structures with different coordination geometry. In this way, they easily build two-dimensional and three-dimensional architectures with definite channels and permanent pores. Owing to their strong oxophilic propensity and hard Lewis acid character, lanthanides effectively succeed in creating robust, stable coordination polymers and MOF structures and viable matrices via strongly binding the coordinating groups of the accurately selected organic linkers. Such unique particularities involve a distinct morphology, diverse crystal structures, uniform porosity, a defined pore size and shape, precisely controlled number and dimensions of channels. Their specifically designed configurations allow the access of guest molecules and a controlled distribution of the metal ions on the surface or within the network. Additionally, the lanthanide ions afford new synergistic Lewis acid sites beneficial for productive catalytic applications. These attractive capabilities of lanthanide coordination polymers enabled them to be fruitfully used as sustainable and recyclable heterogeneous catalysts in diverse organic transformations. like carbon-carbon bond forming, Strecker reaction, CO 2 cycloaddition, Knoevenagel condensation, hydroboration and cyanosilylation. [ABSTRACT FROM AUTHOR]

• Magnetic ordering has been studied for the first time in a lanthanide metal Erbium to the highest pressure of 32 GPa and 10 K in a large volume diamond anvil cell at a spallation neutron source. • The conical ferromagnetic phase observed at ambient pressure is suppressed at high pressures. • The magnetic structural refinements indicate a reduction in the period of magnetic structure in the hexagonal close packed phase. • We show that the magnetic ordering persists in the high pressure double hexagonal close packed phase to 32 GPa. We have studied magnetic ordering in polycrystalline erbium at high pressures up to 32 GPa and low temperatures down to 10 K using neutron diffraction techniques at the Spallation Neutron Source at Oak Ridge National Laboratory, USA. For the hexagonal close-packed (hcp) phase, strong nuclear and magnetic satellite intensities permit a simultaneous refinement of the nuclear and magnetic structures. At 1 GPa of applied pressure, a modulation vector q = γ c ∗ with γ ≈ 2 / 7 for the c -axis modulated and cycloidal phases is consistent with prior single-crystal studies at low pressures. At 6.7 GPa in the hcp phase, we find γ ≈ 0.31 , indicating a reduction in the period of the magnetic structure with respect to the crystal lattice. The magnetic ordering temperature at 6.7 GPa is slightly above 60 K. At 32 GPa in the double hexagonal close-packed phase, the magnetic scattering constrains the magnetic ordering temperature to 25 ± 5 K. Our neutron diffraction study demonstrates that the magnetic ordering persists in the high-pressure double hexagonal close-packed phase of erbium to the highest pressure of 32 GPa. [ABSTRACT FROM AUTHOR]

Properties of cellulose are typically functionalized by organic chemistry means. We progress an alternative facile way to functionalize cellulose by functional group counter-cation exchange. While ion-exchange is established for cellulose, it is far from exploited and understood beyond the most common cation, sodium. We build on our work that established the cation exchange for go-to alkali metal cations. We expand and further demonstrate the introduction of functional cations, namely, lanthanides. We show that cellulose nanocrystals (CNCs) carrying sulfate-half ester groups can acquire properties through the counter-cation exchange. Trivalent lanthanide cations europium (Eu3+), dysprosium (Dy3+) and gadolinium (Gd3+) were employed. The respective ions showed distinct differences in their ability of being coordinated by the sulfate groups; with Eu3+ fully saturating the sulfate groups while for Gd3+ and Dy3+, values of 82 and 41 % were determined by compositional analysis. CNCs functionalized with Eu3+ displayed red emission, those containing Dy3+ exhibited no optical functionality, while those with Gd3+ revealed significantly altered magnetic relaxation times. Using cation exchange to alter cellulose properties in various ways is a tremendous opportunity for modification of the abundant cellulose raw materials for a renewable future. [Display omitted] [ABSTRACT FROM AUTHOR]

Ln 2 Co 3 Ge 5 (Ln = lanthanide) intermetallics possess intriguing electronic and magnetic properties. The compound Sm 2 Co 3 Ge 5 exhibits antiferromagnetic ordering coupled with a magnetic moment that exceeds the theoretical moment of trivalent Sm suggesting a magnetic contribution from Co. Twinning is observed in Sn flux-grown monoclinic Sm 2 Co 3 Ge 5 along (100) planes. While the influence of twin boundaries on superconducting oxides and 2D-materials is well-studied, its effects on bulk lanthanide-based intermetallics are rarely explored. Using monochromated electron energy-loss spectroscopy (EELS) and high-resolution transmission electron microscopy (TEM), we investigate the impact of twin domains on the local strain and electronic structure of Sm 2 Co 3 Ge 5. The boundaries between twinned domains primarily exhibit shear strain and have a constant oxidation state, but fine structure emerges in the Co L 2 , 3 edges at twin boundaries, indicative of 3 d -electron hybridization and occupation of states not present in bulk grain spectra. These findings provide insights into tuning the bulk properties of lanthanide-transition metal systems with complex magnetism. [Display omitted] [ABSTRACT FROM AUTHOR]

This work provides insight into the correlation between the luminescent response of a water-vapour optical fibre sensor and the textural properties of its lanthanide-doped silica coating. To this end, a library of 16 silica xerogels derived from combinations between 2 lanthanide dopants (EuIII, TbIII) and 8 antenna ligands was synthesised and characterised by photoluminescence spectroscopy and N 2 and CO 2 adsorption-desorption isotherms, among others. Based on the best luminescent response and most-suited porous texture, the material doped with TbIII and 2,2′-(4-(2-Ethoxyethoxy)pyridine-2,6-diyl)bis(4,5-dihydrooxazole) was selected to construct the probe. A film of this material was affixed to a commercial silica fibre by dip-coating and the resulting sensor was tested in a climatic chamber with relative humidity ranging from 20 to 90% to obtain normalised time-response and calibration curves at three temperatures. The response was linear up to certain water-vapour concentrations, beyond which abruptly changed to polynomial, acting against the sensor resolution. The adsorption mechanism was elucidated by comparing the isosteric enthalpies of adsorption calculated from the sensor calibration curves to those determined from the monolith water-vapour isotherms, revealing that capillary condensation in the membrane mesopores was the key phenomenon leading to the response deviating from linearity. • Luminescent silica xerogel as the chemical membrane for a fibre optic sensor. • Luminescent xerogel with remarkable Stokes Shift and photostability for sensing. • Relationship between silica coating textural parameters and sensor response. • Relationship between isosteric enthalpy of adsorption and sensor response. • Measurement mechanism explanation in a water vapour fibre optic sensor. [ABSTRACT FROM AUTHOR]

Reports on lanthanide complexes derived from non-steroidal anti-inflammatory drug molecules are still quite scarce in the literature, despite the potential properties of these molecules as therapeutic agents and biological markers. The current literature reports only lanthanide compounds containing the ketoprofenate ligand, most of the time containing coordination water molecules, which causes serious luminescence suppression. This study reports three new classes of highly photoluminescent lanthanide ketoprofenates with general formulas [Ln 2 (keto) 6 (bpy) 2 ] (1) – (3) , [Ln 2 (keto) 6 (phen) 2 ] (4) – (6) and [Ln 2 (keto) 6 (4,4′-dmbpy) 2 ] (7) – (9) (where: Ln = Eu3+, Gd3+ e Tb3+; keto = ketoprofenate anion, bpy = 2,2′-bipyridine, phen = 1,10-phenanthroline and 4,4′-dmbpy = 4,4′-dimethyl-2,2′-bipyridine). These nine complexes were fully characterized and the photophysical studies were carried out in detail. Furthermore, the energy transfer mechanism was completely elucidated with the aid of theoretical calculations using the Sparkle/RM1 method, closely related to the nature of the employed ancillary ligand. The calculated luminescence spectroscopic parameters are in excellent agreement with those obtained experimentally, reinforcing the homobimetallic structure for these complexes. With the highest values of quantum efficiencies (%η) ever reported for lanthanide ketoprofenates, these compounds comprise potential molecules for use as biological markers or anti-inflammatory agents. [Display omitted] • Nine new Ln3+-ketoprofen complexes were synthesized and fully characterized. • Investigate the influence of the N,N-donors ligands in the photoluminescence. • The RM1 model was used to obtain the molecular structures of the Eu3+ complexes. • The intramolecular energy transfer is responsible by high quantum efficiency (η). • These complexes are potential candidates to act as biomarkers. [ABSTRACT FROM AUTHOR]

Phosphate glasses containing Gd3+ ions as ultraviolet (UV) type B light emitters are of interest for applications in phototherapy lamps for treating skin diseases. The composition-structure-property relation in this type of glass systems is thus of interest from fundamental and applied perspectives. In this work, Gd3+-containing glasses were prepared by melting with 50P 2 O 5 -(50 – x)BaO- x Gd 2 O 3 (x = 0, 1, 2, 3, 4, 5 mol %) nominal compositions, and studied comprehensively by X-ray diffraction (XRD), densitometry, Raman spectroscopy, differential scanning calorimetry (DSC), dilatometry, optical absorption, and photoluminescence (PL) spectroscopy with emission dynamics appraisal. XRD supported the amorphous nature of the glasses, whereas the densities of the Gd3+-containing glasses were found to increase with Gd 2 O 3 content. The Raman spectra evolution was indicative of glass depolymerization being induced by Gd3+ ions. DSC results showed that the glass transition temperatures increased with Gd3+ concentration while the glasses exhibited decreased susceptibility for crystallization. Dilatometry ultimately revealed a steady decrease in the coefficient of thermal expansion for the Gd3+-containing glasses indicating tighter networks were realized. The PL evaluation showed that the UVB emission intensity at 312 nm increased linearly with Gd3+ concentration, even though the 6P 7/2 state lifetime reached a maximum for 2 mol % Gd 2 O 3. The PL intensities finally showed strong linear correlations with the thermal parameters linked to the structural evolution thus supporting the interconnection between the properties. [Display omitted] • Composition-structure-property relation studied in melt-quenched UV-emitting phosphate glasses containing Gd3+. • Characterizations by XRD, density, Raman spectroscopy, DSC, dilatometry, optical absorption, and PL spectroscopy. • Glass depolymerization induced by Gd 2 O 3 replacing BaO indicated by Raman spectroscopy. • Gd3+ ions increase glass transition and softening temperatures while decreasing thermal expansion. • PL intensity increase up to 5 mol% Gd 2 O 3 correlated with thermal parameters. [ABSTRACT FROM AUTHOR]

Four new coordination polymers based on Ln3+ and 2,5-diiodoterephthalates (2,5-I-bdc) {[Ln 2 (2,5-I-bdc) 3 (DMF) 4 ]} —were prepared and characterized. Their luminescent properties were compared with other Ln3+ 2,5,-I-bdc complexes; it was shown that these compounds can be used as highly effective sensors on chloro- and nitrobenzene with detection limits of 0.22 mM and 0.16 mM, respectively. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Recently, metal - – organic frameworks (MOFs) with high porosity have drawn extensive attention in water splitting. The present study reports the synthesis of a porous Fe-based MOF by a modified precursor made of magnetite (Fe 3 O 4). Subsequently, a series of undoped and lanthanide -doped (MOFs) are prepared using the solvothermal method. The synthesis provided a high surface area with a high specific surface and pore volume. The synthesized electrocatalyst with a high surface area is demonstrated as an excellent electrocatalyst for the hydrogen evolution reaction (HER) investigated in acidic media. The electrochemical results demonstrated low Tafel slopes (81 and 166 mV dec –−1), high exchange current, high s surface area (C dl) (148.29 and 150.57 mV), and high stability for Au/MIL-53 (Fe)/Gd-Fe 3 O 4 and glassy carbon electrode GCE/MIL-53 (Fe)/La-Fe 3 O 4. The high activity is attributed to the large surface area of the synthesized Fe/ Fe 3 O 4 -based MOF, which is porous and magnetic. The effect of base metal on catalyst performance was discussed. Through the unification of two catalytically active metals as lanthanide, a new opportunity opens up for the development of synergistic systems in multiple applications. [ABSTRACT FROM AUTHOR]