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Chemical methods for the extraction and refinement of technologically critical rare earth elements (REEs) are energy-intensive, hazardous, and environmentally destructive. Current biobased extraction systems rely on extremophilic organisms and generate many of the same detrimental effects as chemical methodologies. The mesophilic methylotrophic bacterium Methylobacterium extorquens AM1 was previously shown to grow using electronic waste by naturally acquiring REEs to power methanol metabolism. Here we show that growth using electronic waste as a sole REE source is scalable up to 10 L with consistent metal yields without the use of harsh acids or high temperatures. The addition of organic acids increases REE leaching in a nonspecific manner. REE-specific bioleaching can be engineered through the overproduction of REE-binding ligands (called lanthanophores) and pyrroloquinoline quinone. REE bioaccumulation increases with the leachate concentration and is highly specific. REEs are stored intracellularly in polyphosphate granules, and genetic engineering to eliminate exopolyphosphatase activity increases metal accumulation, confirming the link between phosphate metabolism and biological REE use. Finally, we report the innate ability of M. extorquens to grow using other complex REE sources, including pulverized smartphones, demonstrating the flexibility and potential for use as a recovery platform for these critical metals.

Terpenes are diverse specialized metabolites naturally found within plants and have important roles in inter-species communication, adaptation and interaction with the environment. Their industrial applications span a broad range, including fragrances, flavors, cosmetics, natural colorants to agrochemicals and therapeutics, yet formal chemical synthesis is economically challenging due to structural complexities. Engineering terpene biosynthesis could represent an alternative in microbial biotechnological workhorses, such as Saccharomyces cerevisiae or Escherichi coli, utilizing sugars or complex media as feedstocks. Host species that metabolize renewable and affordable carbon sources may offer unique sustainable biotechnological alternatives. Methylotrophs are bacteria with the capacity to utilize one-carbon feedstocks, such as methanol or formate. They colonize the phyllosphere (above-ground area) of plants, and many accumulate abundant carotenoid pigments. Methylotrophs have the capacity to take up and use a subset of the rare earth elements known as lanthanides. These metals can enhance one-carbon (methylotrophic) metabolism. Here, we investigated whether manipulating the metabolism enables and enhances terpene production. A carotenoid-deficient mutant potentially liberates carbon, which may contribute to bioproduct accumulation. To test this hypothesis, terpene-producing bacterial strains regulated by two distinct promoters were generated. Wildtype Methylobacterium extorquens, ∆Meta1_3665, a methylotrophic mutant lacking the carotenoid pathway, and an E. coli strain were transformed with an exogenous terpene pathway and grown both in the presence and absence of lanthanides. The extraction, and the comparison of analytical profiles, provided evidence that engineered cultured M. extorquens under control of a native, inducible methylotrophic promoter can yield the sesquiterpene patchoulol when supplemented with lanthanide. In contrast, using a moderate-strength constitutive promoter failed to give production. We demonstrated colonization of the phyllosphere with the engineered strains, supporting the future engineering of selected species of the plant microbiome and with promising implications for the synthetic biology of small molecules.

The development of ultrasensitive thermometric phosphors has become an active area of research due to their appealing applications in the contactless temperature detection field. Herein, the scheelite-related compounds—CaGd 2 (WO 4) 4 : Nd3+, Yb3+ and CaGd 2 (MoO 4) 4 : Nd3+, Yb3+, which exhibit high sensing capacity—are successfully prepared and systematically characterized. The X-ray diffraction analysis reveals that CaGd 2 (WO 4) 4 : Nd3+, Yb3+ exhibits the monoclinic structure, whereas CaGd 2 (MoO 4) 4 : Nd3+, Yb3+ is in the tetragonal phase. The maximum phonon cut-off energy of CaGd 2 (WO 4) 4 : Nd3+, Yb3+ is 929 cm−1, slightly larger than that of CaGd 2 (MoO 4) 4 : Nd3+, Yb3+ (904 cm−1). Irradiated by 980 nm laser, PL spectra consist of the Nd3+: 4F j → 4I 9/2 (j = 7/2, 5/2, 3/2) and Yb3+: 2F 5/2 → 2F 7/2 emissions located in the near-infrared (NIR) range. Negative and positive thermal quenching behaviors are observed for the emissions of Nd3+ (754, 802, and 868 nm) and Yb3+ (1008 nm), respectively, attributed to the cooperative effects of the phonon-assisted energy transfer process of Yb3+ → Nd3+ and excited state absorption process of Nd3+. Moreover, the host material can affect the luminescence properties, thermal enhancement factor of the NIR anti-Stokes emission, and thermal sensing performance of the Nd3+-Yb3+ pair. Consequently, CaGd 2 (MoO 4) 4 : Nd3+, Yb3+ exhibits higher sensing sensitivity (S r-max = ∼6.00%K−1) than CaGd 2 (WO 4) 4 : Nd3+, Yb3+ (S r-max = ∼5.56%K−1). This study provides useful information for the construction of high-performance ratiometric thermometers based on the inverse thermal dependence of the NIR emissions of Nd3+ and Yb3+ ions. [ABSTRACT FROM AUTHOR]

In this account, we will highlight recent progress in the development of multichannel lanthanide‐doped (MC−Ln) nanoprobes for highly efficient serodiagnosis and therapy, with a particular focus on our own work. First, we first provide a classification of the types of MC−Ln nanoprobes based on the contained type and number of signals. The merits of different types of nanoprobes and the reason using lanthanides are elucidated. Then, we provide an overview of the current uses of MC−Ln nanoprobes in serodiagnosis and therapy, focusing on the strategic exploration to improve the diagnostic and therapeutic performance from different perspectives. Finally, we present a prospective outlook on the future development and potential issues of next‐generation MC−Ln nanoprobes. We hope that this timely account will update our understanding of MC−Ln and similar nanoprobes for bioapplications and provide helpful references for the state‐of‐the‐art tools for serodiagnosis and therapy. [ABSTRACT FROM AUTHOR]

Exploring the photocatalytic application of cerium‐based metal–organic frameworks (Ce‐MOFs) has attracted special interest due to the high abundance, low cost, and easy availability of Ce as well as the presence of low energy 4f orbitals and redox Ce (III)/(IV) couple. However, in contrast to the recent emerging study on the development of Ce (IV)‐MOFs as photocatalysts, there are few reports focusing on the photocatalytic performance of Ce (III)‐MOFs. Meanwhile, research on comparing the photocatalytic properties of rare‐earth lanthanide (Ln) ions has rarely been reported. Herein, a novel Ce (III)‐MOF with a formula of (Ce)6(BDC)9(DMF)6(H2O)3·(DMF)3, named CSUST‐4 (CSUST stands for Changsha University of Science and Technology), was successfully synthesized and characterized. The comprehensive analysis of the Ce‐O distance and Ce 3d spectra of CSUST‐4, mixed‐valence Ce (III/IV)‐MOF CSUST‐1, and Ce (IV)‐MOF CSUST‐3 demonstrated that the Ce‐O distance (O from the oxo bridge) can be used as an important reference to assign the valence state of Ce in Ce‐MOFs while the satellite peak around 916.0 eV attributed to Ce (IV) can be utilized to distinguish Ce (IV)‐containing Ce‐MOFs from Ce (III)‐MOFs. Furthermore, the photocatalytic hydrogen evolution (PHE) property of CSUST‐4 by water splitting was also studied, and by utilizing isostructural MOFs CSUST‐4‐Ln (Ln = La, Nd, Eu, Er, Yb) as platforms, the PHE performances of these Ln ions were compared, which evidenced that Ce is a suitable Ln ion to construct MOF materials for PHE in terms of cost and performance. This work contributes to the development of the Ce‐MOF field as well as sheds light on advancing Ce (III)‐MOFs toward potential photocatalytic application. [ABSTRACT FROM AUTHOR]

Four novel lanthanide La (III), Ce (III), Nd (III), and Dy (III) complexes with (Z)‐4‐(benzo[d]thiazol‐2‐ylamino)‐3‐((benzo[d]thiazol‐2‐ylimino)methyl)‐2H‐chromen‐2‐one (L) were prepared and characterized. The novel compounds' structural compositions were elucidated by the application of analytical and spectroscopic methodologies. From physical and chemical measurements, the general formula for the [LnLCl3]2H2O complexes (C1‐C4) was proposed, which was proven by theoretical measurements. Using cisplatin, gentamicin, ampicillin, and ascorbic acid as standards, the compound's anticancer, antibacterial, and antioxidant qualities were assessed, and activities followed the order: Ce (III)L(C2) > Nd (III)L(C3) > Dy (III)L(C4) > La (III)L(C1) > L where the Ce (III) complexes exhibited the highest activity followed by Nd (III) complexes. Molecular docking studies were performed using the MOA2022 software to identify putative binding mechanisms for the methionine adenosyl‐transferases in liver cancer (PDB ID: 5A19) and the most active site of the Bacillus subtilis receptor (PDB ID: 5e6k), where the strength of the interaction increases with the negative binding energy L ˂ [LaLCl3] ˂ [DyLCl3] ˂ [NdLCl3] ˂ [CeLCl3]. [ABSTRACT FROM AUTHOR]

The spatially resolvable multicolored microrods have potential applications in many fields. However, achieving spatially resolved multicolor luminescence tuning on the microrod with a fixed composition remains a daunting challenge. Herein, a strategy is proposed that allows for the tuning of spatially resolved, multicolored upconversion (UC) luminescence (UCL) along a 1D heterogeneous microrod by modifying the pulse width of an external laser. NaYbF4:1 % Ho is identified as an UCL color‐adjustable material, exhibiting pulse width‐dependent multicolored UCL, resulting in a significant regulation of the red/green (R/G) ratio from 0.1 to 10.3 as the pulse width is varied from 0.1 to 10 ms. Such variability can be ascribed to differences in the number of photons incident upon the microrod throughout the period necessary for the UC process to occur. Additionally, NaYbF4:1 %Tm and NaYF4:20 %Yb,1 %Ho are employed as materials that emit blue and green light, respectively, with their UCL colors largely unaffected by changes in the pulse width. Subsequently, a tip‐modified epitaxial growth method is utilized to integrate both UCL color‐adjustable and non‐adjustable segments within the same microrod. Comparing with single‐color or fixed multicolor microrods, our developed multisegmented emissive color adjustable 1D heterogeneous microrods have unique optical characteristics and can carry more optical information. [ABSTRACT FROM AUTHOR]

Linear N‐substituted polyacrylamides bearing tricarboxylic moieties pendant to the backbone are synthesized, and coordinative binding approach is developed to convert them into Gd3+/Eu3+‐metallopolymers. Inner‐sphere coordination of the lanthanide ions with the pendant chelating moieties, together with their outer‐sphere stabilization by the randomly coiled backbone, are the reasons for peculiar water proton relaxation and luminescence properties of the metallopolymers obtained. Indeed, for Gd3+‐metallopolymer, the values of longitudinal and transverse relaxivity (r1 and r2) are 50 and 60 mm−1·s−1, respectively, while for the Eu3+‐counterpart, Eu3+‐centered luminescence is significantly raised compared to Eu3+ aquaions. Coil‐like conformation of the metallopolymer molecules undergoes a swelling at pH values above 5.0 as evidenced by transmission electron microscopy TEM and dynamic light scattering (DLS) data, which is followed by the changes in the Eu3+‐centered luminescence and r1(2)‐values of Gd3+/Eu3+‐metallopolymers. The phosphates additives (adenosine monophosphoric acid (AMP), adenosine diphosphoric acid (ADP), HPO42− and adenosine triphosphoric acid (ATP) induce well detectable changes in both water proton relaxation and luminescence of Gd3+/Eu3+‐metallopolymers. The luminescent changes distinguish AMP from the other phosphates, while the changes in water proton relaxation are greater for HPO42− and ATP compared to AMP and ADP. This study explains this by interplay of the effects associated with the formation of ternary phosphate‐lanthanide‐polymer complexes and stripping of lanthanide ions from the polymer molecules. [ABSTRACT FROM AUTHOR]

The commonly used automotive head‐up display (HUD) technology is confronted with the problems of poor stability in organic resin counterpart and the unsatisfactory display effect of projection lighting source. To solve these issues, developing state‐of‐the‐art materials and designing new HUD schemes with a wide color gamut is of necessity. Herein, a series of pure red/green/blue (R/G/B) upconverting (UC) nano‐glass‐ceramics (GCs) containing lanthanide‐doped NaLuF4 nanocrystals (NCs) are synthesized in a cost‐effective, environment‐friendly, and scalable manner, simultaneously achieving high crystallinity (≈45.44%) and high transparency (>80%). Yb3+ is chosen as the sensitizer to Tm3+ (blue UC)/Ho3+ (green UC), due to its large absorption cross section from ground state 2F7/2 to excited state 2F5/2; meanwhile Er3+, Tm3+ co‐doped into NCs can obtain pure red UC emission via promoting the population of Er3+ red‐emitting 4F9/2 state. Consequently, the as‐prepared materials exhibit high R/G/B color purity of > 80% owing to the energy transfer between different lanthanide ions (Yb3+, Tm3+, Ho3+, and Er3+) upon 980 nm near‐infrared (NIR) laser excitation, and possess superior thermal reversibility/water resistivity. Remarkably, two unprecedented HUD prototypes are constructed to demonstrate the application feasibility of developed pure R/G/B UC GCs. [ABSTRACT FROM AUTHOR]

A new type of diborate clathrochelate (cage) ligand featuring nine inwardly pointing nitrogen donors that form a large, rigid cavity, termed a mausolate, is presented. The cavity size and high denticity make this an attractive delivery vehicle for large radionuclides in nuclear medicine. Metal mausolate complexes are stable to air and water (neutral pH) and display extremely high thermal stability (>400 °C). Lanthanide uptake by the mausolate ligand occurs rapidly in solution at room temperature and once complexed, the lanthanide ions are not displaced by a 250‐fold excess of a competitive lanthanide salt over more than one week. [ABSTRACT FROM AUTHOR]

Exogenous supplementation of L‐arginine (L‐Arg) facilitates the release of nitric oxide (NO) for gas therapy applications in tumor microenvironments rich in H2O2. However, direct administration inevitably leads to the premature release of hydrophilic L‐Arg in the bloodstream, potentially resulting in unstable plasma L‐Arg concentrations and subsequent adverse reactions. Therefore, it is crucial to identify efficient and stable high‐dose L‐Arg delivery carriers, albeit challenging. Here, the study has achieved high (≈94 mg g−1) and stable L‐Arg loading within a 12‐coordinated Yb‐based lanthanide metal‐organic framework (named Yb‐DOBDC, where DOBDC is 2,5‐dihydroxyterephthalic acid). Yb‐DOBDC features size‐matched apertures and oxygen‐rich pore microenvironments, securely entrapping L‐Arg through electrostatic interactions and conjugation effects, thereby enhancing the biostability of the drug during delivery. In vitro experiments demonstrate that L‐Arg‐loaded Yb‐DOBDC (L‐Arg@Yb‐DOBDC) promotes NO release upon H2O2 stimulation, and the Yb‐DOBDC framework exhibits good biocompatibility within cells. More interestingly, the near‐infrared‐luminescence‐emitting Yb‐DOBDC exhibits a "turn‐off" behavior upon gradual loading of L‐Arg, enabling self‐quantifying luminescence detection during the encapsulation process. Consequently, the L‐Arg@Yb‐DOBDC system designed in this work, with its high/stable loading capacity and self‐quantifying luminescence detection capability, holds theoretical research value and potential practical application prospects. [ABSTRACT FROM AUTHOR]

AbstractA commonly employed method for identifying aspirin involves the use of either HPLC or electrochemical analysis. In this article, a highly selective and ultrasensitive fluorescent sensor with convenient synthesis steps for the detection of aspirin was reported. This study introduced a novel hybrid organic-inorganic optical network hydrogel achieved through the integration of a complex of Tb-xanthan gum (XG) into the backbone of polyvinyl alcohol (PVA). This hydrogel fabricated in a water-based environment, exhibits weak green luminescence at the beginning owing to the chelation and sensitization of lanthanide (Tb3+) ions by ligands. Interestingly, the green emission intensity observed at λex = 346 nm, is enhanced by dual energy-transfer channels from XG and aspirin. We experimentally demonstrate that luminescent Tb3+-XG complex-binding aptamer hydrogels can selectively detect aspirin from 250 nM to 1 μM with a detection limit of 150 nM in this study. Furthermore, we discuss the resulting structure, thermal stability, excellent swelling properties, mechanical characteristics, and morphology of this light-emission material in detail. The success of this method will open up new opportunities for the use of hydrogels in visual fluorescence sensing applications. [ABSTRACT FROM AUTHOR]

Two series of 3d‐Gd mixed‐metal phosphonate complexes with either only two gadolinium centers such as {Gd2}, {Ni2Gd2}, {Co4Gd2}, {Co8Gd2}, {Fe6Gd2}, and {Fe17Gd2} or more than two gadoliniums such as {Co8Gd4}, {Mn8Gd4}, {Co4Gd6}, {Mn4Gd6}, {Co6Gd8}, {Ni5Gd8}, {Ni6Gd6}, {Co8Gd8}, and {Mn9Gd9} have been solvothermally prepared and magnetothermally studied. The nearly identical environments of the Gd(III) dimer in the first series allow us to qualitatively analyze the effect of magnetic exchange coupling on the magnetocaloric effect (MCE). By doubling, tripling, or quadrupling of the Gd(III) centers, the second series of 3d‐Gd mixed‐metal complexes was built to further test the other effects of exchange couplings on MCE in more complicated circumstances. For the antiferromagnetic coupling cases, the results are nearly identical but diversify when topological spin frustrations are created, whose massive low‐lying excited spin states help enhance MCE. For presumably ferromagnetically coupled ones, albeit are rare in phosphonate complexes, they do exhibit excellent MCE. Meanwhile, the complexes with weakly coupled metal centers serve as excellent examples for studying the effect of molecular mass on MCE when its magnitude is expressed in the unit of Joule per kilogram, from which we can see the values are directly proportional to the percentage of the Gd(III) ions in molecular weight. [ABSTRACT FROM AUTHOR]

Polymetallic layered double hydroxides are promising cost-effective catalysts for the oxygen evolution reaction (OER) due to their versatile anionic and cationic tunability. Nevertheless, several challenges persist, notably, issues related to low electrical conductivity, poor catalytic activity, and stability, especially at high current density. Herein, we report the design of Ce- and La-doped CoNiFe-layered double hydroxide (CeLaCoNiFe-LDH) nanosheets through a facile and scalable in situ self-assembly strategy that displays enhanced OER activity. Experimental and theoretical investigations provide insights into the impact of Ce-and La-doping by comparing CeCoNiFe-LDH, LaCoNiFe-LDH, and pristine CoNiFe-LDH, all synthesized using the same methodology. These results reveal that doping Ce3+ and La3+ into CoNiFe-LDH substantially improves its electronic structure, resulting in enhanced conductivity, more oxygen vacancies (Vo), electron interaction, and active site formation. Consequently, significantly reduced overpotentials of 175, 314, and 424 mV at 10, 100, and 500 mA cm−2, respectively, and a highly stable current density of 120 h in 1 M KOH were achieved. Notably, these performance metrics surpass those of unmodified LDHs and are competitive with many lanthanide-doped transition metal-based LDH electrocatalysts, as well as noble metal catalysts like ruthenium catalysts. This work represents a pioneering effort in doping Ce3+ and La3+ ions into a functional CoNiFe-based electrocatalyst, offering inspiring OER performance and scalability potential. [ABSTRACT FROM AUTHOR]

The effect of La, Ce, Pr and Nd ions on four Ln(ligand)3 complexes and at three DFT levels of calculation was analyzed. Four ligands were chosen, three of which were based on the 1,2,3-triazole ring. The DFT methods used were B3LYP, CAM-B3LYP and M06-2X. The relationships established were between the geometric parameters, atomic charges, HOMO-LUMO energies and other molecular properties. These comparisons and trends will facilitate the synthesis of new complexes by selecting the ligand and lanthanide ion best suited to the desired property of the complex. The experimental IR and Raman spectra of Ln(2b′)3 complexes where Ln = La, Ce, Pr, Nd, Sm, Gd, Dy, Ho and Er ions have been recorded and compared to know the effect of the lanthanide ion on the complex. The hydration in these complexes was also analyzed. Additionally, the effect of the type of coordination center on the ability of an Ln(ligand)3 complex to participate in electron exchange and hydrogen transfer was investigated using two in vitro model systems—DPPH and ABTS. [ABSTRACT FROM AUTHOR]

Sulfadiazine (SFZ) is an inexpensive large‐consumption antibiotic used for treat bacterial infections but an excess of residues in food can be harmful. Fast and specific luminescence detection of SFZ is highly challenging because of the interference of structurally similar antibiotics. In this work, we develop a two‐dimensional europium‐organic coordination polymer with excellent luminescence and water stability for highly specific detection of SFZ in the range of 0–0.2 mM. Structural analysis shows that the high stability of coordination polymer is due to the high coordination number of europium ion and the special chelating coordination structure of ligand. The experiment results revealed that the high selectivity and effectively luminescence quenched behaviour of coordination polymer toward SFZ is caused by highly efficient inner filter effect. [ABSTRACT FROM AUTHOR]

Emission from metal–organic frameworks (MOFs) made from Eu3+ and 1,3,5‐benzenetricarboxylic acid (BTC) is enhanced eightfold by doping with Y3+ and Ca2+ ions. The Ca2+ ions are shown to substitute into the MOFs, and the MOFs structure is shown to be retained at high Y3+ doping levels. The emission enhancement is shown to be associated with variations in the local electric field at the Eu3+ centers in the MOFs. Calculations indicate that the HOMO and LUMO levels vary considerably with both Y3+ doping and with low‐level Ca2+ doping. These then modulates Eu3+ concentration quenching, ligand‐metal energy transfer processes, and the local electric field at the Eu3+ centers, qualitatively accounting for the primary observed features. For UV excitation (250, 295, and 393 nm, respectively), the greatest emission enhancement comes from the doped MOFs with 10% Eu3+, 89% Y3+, and 1% Ca2+. In a photonic barcode application, the doped MOFs are shown to facilitate increased information storage density, and in a fingerprinting application, they are displayed to lead to higher photostability and reduced materials demand. [ABSTRACT FROM AUTHOR]

Nicotine (3-(1-methyl-2-pyrrolidinyl)pyridine) is one of the most common addictive substances, causing the trace detection of nicotine to be very necessary. Herein, we designed and prepared a functionalized nanocomposite CS-PAA (NaYF4:19.5%Yb,0.5%Tm@NaYF4-PAA) using a simple method. The nicotine concentration was quantitatively detected through the inhibition of choline oxidase activity by nicotine and the luminescence intensity of CS-PAA being quenched by Fe3+. The mechanism of Fe3+ quenching CS-PAA emission was inferred by luminescence lifetime and UV–vis absorption spectra characterization. During the nicotine detection, both excitation (980 nm) and emission (802 nm) wavelengths of CS-PAA enable the avoidance of the interference of background fluorescence in complicated food objects, thus providing high selectivity and sensitivity with a linear range of 5–750 ng/mL and a limit of detection of 9.3 nM. The method exhibits an excellent recovery and relative standard deviation, indicating high accuracy and repeatability of the detection of nicotine. [ABSTRACT FROM AUTHOR]

Lanthanide (Ln) based mononuclear single‐molecule magnets (SMMs) provide probably the finest ligand regulation model for magnetic property. Recently, the development of such SMMs has witnessed a fast transition from coordination to organometallic complexes because the latter provides a fertile, yet not fully excavated soil for the development of SMMs. Especially those SMMs with heterocyclic ligands have shown the potential to reach higher blocking temperature. In this minireview, we give an overview of the design principle of SMMs and highlight those “shining stars” of heterocyclic organolanthanide SMMs based on the ring sizes of ligands, analysing how the electronic structures of those ligands and the stiffness of subsequently formed molecules affect the dynamic magnetism of SMMs. Finally, we envisaged the future development of heterocyclic Ln‐SMMs. [ABSTRACT FROM AUTHOR]

In this study, the pyrroloquinoline quinone (PQQ) high-yield mutant J1-1 of Methylobacterium glucophilum MP688 was used to do bioinformatics analysis to extract the two methanol dehydrogenase (MDH) genes from the genome, mpq0771 and mpq2496. The effects of Ca2+ and La3+ on bacterial growth, PQQ synthesis, MDH expression, and enzyme activity were explored, as well as the roles of the two enzymes in methanol metabolism. The results showed that Ca2+ and La3+ both increased J1-1 bacteriophage growth and decreased PQQ synthesis in the context of fast viral development. In the presence of Ca2+, mpq0771 expression increased in strain J1-1. La3+ inhibited mpq0771 expression while promoting mpq2496 expression and increasing total bacterial MDH viability. The knockout bacteria J1-1Δmpq0771 could not grow in methanol, but with the addition of La3+, it could grow in methanol and synthesize PQQ, and MDH activity was identified. The product encoded by mpq0771 was a Ca2+-dependent MDH, and the product encoded by mpq2496 was a La3+-dependent MDH, and La3+ could increase the production of mpq2496 and replace mpq0771 as a methanol dehydrogenase.

A lutetium(III) complex based on the anion of the ligand dimethyl (2,2,2-trichloroacetyl)phosphoramidate (HL) and tetraphenylphosphonium, of composition PPh4[LuL4] (L = CAPh = carbacylamidophosphate), or (C24H20)[Lu(C4H6Cl3NO4P)4], has been synthesized and structurally characterized. The X-ray diffraction study of the compound revealed that the lutetium ion is surrounded by four bis-chelating CAPh ligands, forming the complex anion [LuL4]− with a coordination number of 8[O] for LuIII, while PPh4+ serves as a counter-ion. The coordination geometry around the Lu3+ ion was determined to be a nearly perfect triangular dodecahedron. The complex crystallizes in the monoclinic crystal system, space group P21/c, with four molecules in the unit cell. Weak hydrogen bonds O...HC(Ph), Cl...HC(Ph) and N...HC(Ph) are formed between the cations and anions. For a comparative study, HL-based structures were retrieved from the Cambridge Structural Database (CSD) and their geometries and conformations are discussed. A Hirshfeld surface analysis was also performed.

Hydrochromic luminescent materials that are responsive to water or moisture have attracted considerable attention owing to their extensive use in sensing and information security. However, fine‐tuning hydrochromic response to water content remains unfulfilled research, posing constraints in the widespread application of hydrochromic luminescence. This study reports a 0D Rb3TbF6 perovskite with highly controllable hydrochromic characteristics. The Rb3TbF6 crystals exhibit a distinct hydrochromic luminescence switching after B‐site doping with Eu3+, stemming from Rb3TbF6 to Rb2TbF5 transformation that triggers intra‐crystal Tb3+‐to‐Eu3+ energy transfer. Through A‐site alkaline metal alloying, the sensitivity of the perovskite to water stimuli is precisely tuned, rendering distinct responses over a wide range of humidity conditions (RH: 1–90% RH) and water levels (v/v: 0.5–55%). As an added benefit, the hydrochromic crystals also show excellent repeatability and photothermal stability. These advances on hydrochromic materials provide exciting opportunities in water detection, humidity sensing, and multi‐level information encryption. [ABSTRACT FROM AUTHOR]

A series of TADF‐active compounds: 0D chiral Ln−Ag(I) clusters L‐/D‐Ln2Ag28‐0D (Ln=Eu/Gd) and 2D chiral Ln−Ag(I) cluster‐based frameworks L‐/D‐Ln2Ag28‐2D (Ln=Gd) has been synthesized. Atomic‐level structural analysis showed that the chiral Ag(I) cluster units {Ag14S12} in L‐/D‐Ln2Ag28‐0D and L‐/D‐Ln2Ag28‐2D exhibited similar configurations, linked by varying numbers of [Ln(H2O)x]3+ (x=6 for 0D, x=3 for 2D) to form the final target compounds. Temperature‐dependent emission spectra and decay lifetimes measurement demonstrated the presence of TADF in L‐Ln2Ag28‐0D (Ln=Eu/Gd) and L‐Gd2Ag28‐2D. Experimentally, the remarkable TADF properties primarily originated from {Ag14S12} moieties in these compounds. Notably, {Ag14S12} in L‐Eu2Ag28‐0D and L‐Gd2Ag28‐2D displayed higher promote fluorescence rate and shorter TADF decay times than L‐Gd2Ag28‐0D. Combined with theoretical calculations, it was determined that the TADF behaviors of {Ag14S12} cluster units were induced by 4 f perturbation of Ln3+ ions. Specially, while maintaining ΔE(S1–T1) small enough, it can significantly increase k(S1→S0) and reduce TADF decay time by adjusting the type or number of Ln3+ ions, thus achieving the purpose of improving TADF for cluster‐based luminescent materials. [ABSTRACT FROM AUTHOR]

Lanthanide‐doped scintillators have the ability to convert the absorbed X‐ray irradiation into ultraviolet (UV), visible (Vis), or near‐infrared (NIR) light. Lanthanide‐doped scintillators with excellent persistent luminescence (PersL) are emerging as a new class of PersL materials recently. They have attracted great attention due to their unique "self‐luminescence" characteristic and potential applications. In this review, we comb through and focus on current developments of lanthanide‐doped persistent luminescent scintillators (PersLSs), including their PersL mechanism, synthetic methods, tuning of PersL properties (e. g. emission wavelength, intensity, and duration time), as well as their promising applications (e. g. information storage, encryption, anti‐counterfeiting, bio‐imaging, and photodynamic therapy). We hope this review will provide valuable guidance for the future development of PersLSs. [ABSTRACT FROM AUTHOR]

Coordination complexes of lanthanide metals with tris-1-naphthylphosphine oxide (Nap3PO, L) have not been previously reported in the literature. We describe here the formation of lanthanide(III) nitrate complexes Ln(NO3)3L4 (Ln = Eu to Lu) and the structures of [Ln(NO3)3L2]·2L (Ln = Eu, Dy, Ho, Er) and L. The core structure of the complexes is an eight-coordinate [Ln(NO3)3L2] with the third and fourth ligands H-bonded via their oxygen atoms to one of the naphthyl rings. The structures are compared with those of the analogous complexes of triphenylphosphine oxide and show that the Ln-O(P) bond in the Nap3PO complexes is slightly longer than expected on the basis of differences in coordination numbers. The reaction solutions, investigated by 31P and 13C NMR spectroscopy in CD3CN, show that coordination of L occurs across the lanthanide series, even though complexes can only be isolated from Eu onwards. Analysis of the 31P NMR paramagnetic shifts shows that there is a break in the solution structures with a difference between the lighter lanthanides (La–Eu) and heavier metals (Tb–Lu) which implies a minor difference in structures. The isolated complexes are very poorly soluble, but in CDCl3, NMR measurements show dissociation into [Ln(NO3)3L2] and 2L occurs. [ABSTRACT FROM AUTHOR]

The core-level aluminum excited spectra for lanthanum, the eponymous parent lanthanide metal, are presented together with exemplar spectra highlighting the metals reactivity from reaction with background chamber gases. Recommendations are given for the background integrations limits and form, together with comments on sensitivity factors. [ABSTRACT FROM AUTHOR]

Lanthanide Single‐Molecule Magnets are fascinating objects that break magnetic performance records with observable magnetic bistability at the boiling temperature of liquid nitrogen, paving the way for potential applications in high‐density data storage. The switching of lanthanide SMM has been successfully achieved using several external stimuli such as redox reaction, pH titration, light irradiation or solvation/desolvation thanks to the high sensitivity of the magnetic anisotropy to any structural change in the lanthanide surrounding. Nevertheless, the use of applied high pressure as an external stimulus is largely underused, especially considering that it can be combined with high pressure X‐ray diffraction to establish a complementary structure‐property relationship. This Concept article summarizes the few relevant examples of investigations of lanthanide SMMs under applied high pressure, provides conclusions on the effect of such stimulus on molecular structures and magnetic anisotropy, and finally draws perspective on the future development of magnetic measurements under applied pressure. [ABSTRACT FROM AUTHOR]

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This paper represents a simplistic hydrothermal method for the synthesis of lanthanide (Ln3+)-doped (Ln= Eu, Dy) alkaline earth metal fluoride, i.e., CaF2 nanocrystals coated with poly(acrylic acid) (PAA). The structural and optical characterization of as-prepared nanocrystals is performed using scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), Fourier transform infrared spectrum (FTIR), thermogravimetric analysis (TGA), photoluminescence spectroscopy (PL), and PL lifetime measurements. It is observed that CaF2 exhibits strong red emission when doped with Eu3+ (5 mol%) ions, whereas it shows strong blue and yellow emission when doped with Dy3+ (2 mol%) ions. PAA coating helps to enhance the stability as well as water dispersibility of the nanocrystals. Moreover, this method can be extended to make other lanthanide-doped alkaline earth metal fluoride nanocrystals. The high photoluminescence efficiency and water solubility of the nanocrystals make the material to be used in many fields of optical devices as well as biological applications. [ABSTRACT FROM AUTHOR]

The coordination of hydrotris[3‐(2‐furyl)pyrazol‐1‐yl]borate (Tp2‐Fu, C21H16BN6O3) to lanthanide(III) ions is achieved for the first time with the complex [Ln(Tp2‐Fu)2](BPh4)·xCH2Cl2 (1‐Ln has Ln = Ce and x = 2; 1‐Dy has Ln = Dy and x = 1). This was accomplished via both hydrous (Ln = Ce) and anhydrous methods (Ln = Dy). When isolating the dysprosium analogue, the filtrate produced a second crop of crystals which were revealed to be the 1,2‐borotropic‐shifted product [Dy(κ4‐Tp2‐Fu)(κ5‐Tp2‐Fu*)](BPh4) (2) {Tp2‐Fu* = hydrobis[3‐(2‐furyl)pyrazol‐1‐yl][5‐(2‐furyl)pyrazol‐1‐yl]borate}. We conclude that the presence of a strong Lewis acid and a sterically crowded coordination environment are contributing factors for the 1,2‐borotropic shifting of scorpionate ligands in conjunction with the size of the conical angle with the scorpionate ligand. [ABSTRACT FROM AUTHOR]

To minimize the use of organic solvents and achieve a selective adsorption separation of minor actinides (MA(III)) and Ln(III), adsorbents consisting of SiO2–P particles impregnated with hexaoctylnitrilotriacetamide (HONTA) were prepared. Batch experiments were performed to evaluate the adsorption properties of the HONTA/SiO2–P adsorbent for MA(III) and simulated fission products in HNO3 solution. The uniform distribution of Eu(III) on the adsorbent was confirmed via particle-induced X-ray emission analysis, and X-ray photoelectron spectroscopy revealed that EuNO3 was the adsorbed species. This study provides a simplified process for the separation of MA(III) using a HONTA/SiO2–P-packed column. [ABSTRACT FROM AUTHOR]

Considering the growing interest in lanthanide‐based multifunctional materials two mixed‐ligand complexes [Ln(L)3bipy] (Ln=TbIII, DyIII) with carbacylamidophosphate (CAPh) type ligand – dimethyl‐N‐trichloroacetylamidophosphate (HL) and additional bidentate ligand 2,2'‐bipyridine (bipy) were obtained and studied by X‐ray diffraction study, thermal gravimetric analysis, and luminescence spectroscopy. The obtained complexes are monomeric and isostructural with earlier reported europium analog and crystallizes in the monoclinic system (space group C2/c). They are stable during long‐term storage for at least a couple of years as well as thermally stable up to nearly 200 °C. Both complexes exhibit f–f luminescence upon excitation into the 2,2'‐bipyridine absorption band, being emitters of green (TbIII) and yellow (DyIII) light. The luminescence intensity of the obtained complexes decreases constant exposure to UV radiation for several hours and then stays constant for at least till 32 h. [ABSTRACT FROM AUTHOR]

A biocompatible and versatile silk‐based functional ink with hydrophilic upconversion nanoparticles (UCNPs) that can be printed or painted on arbitrary substrates, including biological surfaces is demonstrated. Hydrophilic UCNPs, ready to be dispersed in aqueous silk fibroin solution, are synthesized in large quantities via facile hydrothermal synthesis using citric acid. Based on a systematic study of dopant control to achieve robust red emission from citrate‐capped UCNPs, three primary colors are obtained, which serve as the basis for the expansion of the color palette. The synthesized UCNPs are homogeneously dispersed in regenerated silk fibroin solutions derived from Bombyx mori cocoons to produce water‐based functional inks. Cyan, magenta, and yellow (CMY) inks are created by combining red, green, and blue (RGB) inks. Demonstrator devices, where a variety of colorful patterns and codes are revealed only under near‐infrared irradiation, are realized through stencil printing or brush painting on flexible polymer films, fruit, leaves, silkworm cocoons, and pig skin. The patterns and codes are highly heat resistant (≈230 °C) and can be easily washed off with water after use. The printable/paintable inks and functions proposed here will provide new opportunities for applications where sustainability, biocompatibility, and intentional luminescence are simultaneously required. [ABSTRACT FROM AUTHOR]

Applying a single molecular probe to monitor enzymatic activities in multiple, complementary imaging modalities is highly desirable to ascertain detection and to avoid the complexity associated with the use of agents of different chemical entities. We demonstrate here the versatility of lanthanide (Ln3+) complexes with respect to their optical and magnetic properties and their potential for enzymatic detection in NIR luminescence, CEST and T1 MR imaging, controlled by the nature of the Ln3+ ion, while using a unique chelator. Based on X‐ray structural, photophysical, and solution NMR investigations of a family of Ln3+ DO3A‐pyridine model complexes, we could rationalize the luminescence (Eu3+, Yb3+), CEST (Yb3+) and relaxation (Gd3+) properties and their variations between carbamate and amine derivatives. This allowed the design of LnLGal5 ${{{\bf L n L}}_{{\bf G a l}}^{5}}$ probes which undergo enzyme‐mediated changes detectable in NIR luminescence, CEST and T1‐weighted MRI, respectively governed by variations in their absorption energy, in their exchanging proton pool and in their size, thus relaxation efficacy. We demonstrate that these properties can be exploited for the visualization of β‐galactosidase activity in phantom samples by different imaging modalities: NIR optical imaging, CEST and T1‐weighted MRI. [ABSTRACT FROM AUTHOR]

The effects of Gd content on the solidification path and microstructure of an AlSi7Mg0.3 alloy have been studied. Two different Gd levels, 0.1 and 0.5 mass%, respectively, have been investigated while the material has been solidified at low (0.2 °C s−1) and high (1.3 °C s−1) cooling rates. Computer-aided thermal analysis and metallographic techniques have been used to study the solidification and microstructural evolution of the alloy at different Gd contents and cooling rates. The results show how Gd has no effect on the grain refinement at both cooling rates. The eutectic structure is unaffected at Gd level of 0.1 mass%. A concentration of 0.5 mass% Gd promotes the precipitation of the gadolinium phosphide (GdP) phase instead of aluminium phosphide (AlP) compounds, thus suppressing the eutectic plateau during the solidification and serving as nucleant for the GdAl2Si2 phase. The eutectic Si crystals solidified at low cooling rate are refined at 0.5 mass% Gd content, while the morphology of Si crystals is only partially modified at high cooling rate. [ABSTRACT FROM AUTHOR]

Two new lanthanide mercury materials, [Gd(IA)3(H3O)2Hg3Br6]nCl2n (1) and [La(IA)3(H3O)2Hg3Br6]nCl2n (2) (IA = isonicotinic anion), have been prepared under solvothermal conditions and characterized by single-crystal X-ray diffraction techniques. They are isomorphic and characterized by a three-dimensional (3-D) framework structure. The lanthanide ions are bound by eight oxygen atoms to exhibit a square antiprismatic geometry. The solid-state photoluminescence experiment discovers that compound 1 shows a strong emission in the red region. Compound 1 possesses CIE (Commission Internationale de I'Éclairage) chromaticity coordinates of 0.7347 and 0.2653. Its CCT (correlated color temperature) is 6514 K. Compound 2 displays yellow photoluminescence and it has CIE chromaticity coordinates of 0.4411 and 0.5151. The CCT of compound 2 is 3633 K. Solid-state UV/Vis diffuse reflectance spectra revealed that their semiconductor band gaps are 2.16 eV and 2.85 eV, respectively. [ABSTRACT FROM AUTHOR]

Two new lanthanide-complexes based on the 5-nitropicolinate ligand (5-npic) were obtained and fully characterized. Single-crystal X-ray diffraction revealed that these compounds are isostructural to a Dy-complex, previously published by us, based on dinuclear monomers link together with an extended hydrogen bond network, providing a final chemical formula of [Ln2(5-npic)6(H2O)4]·(H2O)2, where Ln = Dy (1), Gd (2), and Tb (3). Preliminary photoluminescent studies exhibited a ligand-centered emission for all complexes. The potential antitumoral activity of these materials was assayed in a prostatic cancer cell line (PC-3; the 2nd most common male cancerous disease), showing a significant anticancer activity (50–60% at 500 μg·mL−1). In turn, a high biocompatibility by both, the complexes and their precursors in human immunological HL-60 cells, was evidenced. In view of the strongest toxic effect in the tumoral cell line provided by the free 5-npic ligand (~ 40–50%), the overall anticancer complex performance seems to be triggered by the presence of this molecule. [ABSTRACT FROM AUTHOR]

ObjectivesThe aim of this study was to analyze the precipitation of Cerium(III)nitrate hexahydrate [Ce(NO3)3] or Samarium(III)nitrate hexahydrate [Sm(NO3)3] solutions on human enamel with and without a salivary pellicle. Investigated parameters were At%Ce and At%Sm measured using energy dispersive x-ray spectroscopy (EDX) after test solution (two concentrations) application.Materials and methodsPrecipitation of Ce(NO3)3 and Sm(NO3)3 solutions was examined on human enamel with and without a salivary pellicle. 6 enamel specimens each were obtained from 12 freshly extracted human third molars. These specimens were ground flat and polished. A salivary pellicle was created on 3 of the 6 specimens per tooth by storing the samples in human saliva. Subsequently, an aqueous solution of Ce(NO3)3 was applied to 2 of the 6 specimens (one with, one without salivary pellicle) for 60 s. The same was carried out with an aqueous solution of Sm(NO3)3 on 2 further specimens. The remaining 2 specimens from each tooth were treated with demineralized water (negative control). Ce(NO3)3 and Sm(NO3)3 solutions were applied at 25 or 50 wt% (aqueous solutions). The test materials and concentrations were distributed using a randomization table. After 60 s exposure and rinsing with demineralized water, the elemental composition (Ce, Sm, Ca, P, O, N, Na, Mg) of the enamel surface was analyzed by EDX. Atomic percentages (At%), differences (ΔAt%) and calcium/phosphorous-ratios (Ca/P-ratios) were calculated and analyzed non-parametrically (α = 0.05).Results2.0–2.3 At%Ce (median) was detected on Ce(NO3)3-treated enamel and 0.4–0.7 At% Sm (median) was detected on Sm(NO3)3-treated enamel. Ce was only detected on the surfaces after application of Ce(NO3)3, Sm only after application of Sm(NO3)3. The Ca/P-ratio was significantly lower (1.37–1.59; p = 0.028) after the application of 25% and 50%Ce(NO3)3 as well as 50%Sm(NO3)3 compared to the control treatment (demineralized water; 1.61–1.63). After treatment with Ce(NO3)3, At%Ca and At%Na were significantly lower (p ≤ 0.043) compared to treatment with Sm(NO3)3. No significant differences were found between specimens treated with 25% or 50% lanthanide nitrate solution. Presence of a salivary pellicle had no significant influence on the measured At% with the exception of specimens treated with 50% Sm(NO3)3 with increased At%Sm (p ≤ 0.046).ConclusionsCe(NO3)3 and Sm(NO3)3 precipitate on human enamel independently of the presence of a salivary pellicle.

Interaction of the lanthanide nitrates M(NO3)3 (M = Gd, Eu) with methylcucurbit[5]uril (Me10Q[5]) in the presence of transition metal chlorides (ZnCl2 and FeCl3) in acidic media resulted in the isolation of the complexes [Me10Q[5]Gd(H2O)2Cl Gd(H2O)6](ZnCl4)2∙Cl∙8.9H2O (1) and [Me10Q[5]Eu(H2O)3Cl(H3O)](FeCl4)3 (2). The molecular structures of 1 and 2 have been determined by single crystal X-ray crystallography, and reveal discrete complexes which are involved in dense stacking with adjacent Me10Q[5]s linked via H-bonding and/or metal anions resulting in a supramolecular assembly.

Two series of rare earth coordination compounds have been synthesized (Na[RE(L4)] (labeled as 1RE) and PPh4[RE(L4)] (labeled as 2RE), where RE = Y3+, Eu3+, Tb3+, L = 2,2,2-trichloro-N-(diphenylphosphoryl)acetamide) to determine the possibility of modifying their photophysical and magnetical properties by changing the counterion. The crystal structure of 1RE was determined based on the single-crystal X-ray diffraction and the crystal structure of 2RE was determined based on quantum chemistry computational procedures. Characterization of the physicochemical properties of the compounds was carried out using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), 1H and 31P NMR spectroscopy as well as FT-IR, absorption and luminescence spectroscopy in the temperature range of 300 - 77 K. The rate constants of radiative (Arad) and non-radiative (Anrad) transitions, intrinsic (QLnLn) and overall (QLnL) emission quantum yields, sensitization efficiency (ηsens), the experimental and theoretical intensity parameters (Ωλ), the forward (WS, WT) and backward (WbS, WbT) intramolecular energy transfer (IET) rates were determined. Magnetic properties of Tb3+ compounds were studied in a constant field of 0.5 T in the temperature range of 1.8–300 K. Dynamic AC magnetic susceptibility measurements were carried out as a function of temperature and frequency for 1Tb and 2Tb. Only in the case of 2Tb, in the presence of an external DC field, a slight temperature dependence of in-phase χ′ and out-of-phase χ'' susceptibility was recorded. Based on experimental and theoretical results, the significant effect of counterion on the photophysical and magnetic properties of RE chelates has been demonstrated and clarified, providing valuable guidance for the design of bifunctional electromagnetic radiation converters.

A new lanthanide coordination polymer, poly[[triaquabis(μ4-phthalato)(μ3-pyridine-2,5-dicarboxylato)dipraseodymium] monohydrate], {[Pr2(C7H3NO4)2(C8H4O4)(H2O)3]·H2O}n or {[Pr2(phth)2(pydc)(H2O)3]·H2O}n, (pydc2− = pyridine-2,5-dicarboxylate and phth2− = phthalate) was synthesized and characterized, revealing the structure to be an assembly of di-periodic {Pr2(pydc)(phth)2(H2O)3}n layers. Each layer is built up by edge-sharing {Pr2N2O14} and {Pr2O16} dimers, which are connected through a new coordination mode of pydc2− and phth2−. These layers are stabilized by internal hydrogen bonds and π–π interactions. In addition, a three-dimensional supramolecular framework is built by interlayer hydrogen-bonding interactions involving the non-coordinated water molecule. Thermogravimetric analysis shows that the title compound is thermally stable up to 400°C.

This study presents the synthesis and comprehensive characterization of undoped MoO3 and its cerium (Ce) and iron (Fe) doped counterparts via hydrothermal route, with a 5 % doping concentration. Structural analysis by X-ray diffraction confirmed the formation of MoO3 with successful doping. UV–vis spectroscopy demonstrated tunable optical properties, with band gap energies of 2.3 eV, 2.0 eV, and 2.8 eV for undoped, Ce-doped and Fe-doped MoO3 respectively. Morphological investigation using scanning electron microscopy revealed distinct nanostructures, including nanorods, agglomerated nanoparticles, and pebble-like structures, influenced by doping. Electrochemical characterization through cyclic voltammetry and potentio electrochemical impedance spectroscopy showcased superior charge storage capacity in Fe-doped MoO3, attributed to the largest area under the curve in cyclic voltammograms. Fe-doped MoO3 exhibited lowest resistance as compared to undoped and Ce doped MoO3, suggesting enhanced conductivity. The presence of a Warburg element in all samples indicated diffusion-limited electrochemical processes. The variation of log (scan rate) with log (current) revealed distinct charge transfer mechanisms, with near-unity slopes for doped samples and a slope near 0.5 for undoped MoO3. These findings provide insights into the tunable properties of doped MoO3, offering potential applications in various electrochemical devices.

Hydrogen‐bonded organic frameworks (HOFs) have shown promise in various fields; however, the construction of HOF/polymer hybrid membranes that can maintain both structural and functional integrity remains challenging. In this study, we here fabricated a new HOF (HOF‐50) with reserved polymerizable allyl group via charge‐assisted H‐bonds between the carboxylate anion and amidinium, and subsequently copolymerized the HOF with monomers to construct a covalently bonded HOF/polymer hybrid (polyHOF) membrane. The resulting polyHOF membrane not only exhibits customizable mechanical properties and extreme stability, but also shows an exceptional ratiometric luminescent temperature‐sensing function with very high sensitivity and visibility even when the lanthanide content is two orders of magnitude lower than that of the reported mixed‐lanthanide metal–organic frameworks (MOFs) and lanthanide‐doped covalent organic frameworks (COFs). This orthogonal postsynthesis copolymerization strategy may provide a general approach for preparing covalently connected HOF/polymer hybrid membranes for diverse applications. [ABSTRACT FROM AUTHOR]

The photoluminescent properties of lanthanide complexes have been thoroughly investigated; however, there have been much fewer studies showcasing their potential use in ionizing radiation detection. In this work, we delve into the photo‐ and radio‐induced luminescence of a series of lanthanide‐bearing organic‐inorganic hybrids and their potential as a platform for X‐ray scintillation and imaging. The judicious synergy between lanthanide cations and 2,6‐di(1H‐pyrazol‐1‐yl)isonicotinate (bppCOO−) ligands affords six new materials with three distinct structures. Notably, Eu‐bppCOO‐1 and Tb‐bppCOO‐2 display sharp fingerprint X‐ray‐excited luminescence (XEL), the intensities of which can be linearly correlated with the X‐ray dose rates over a broad dynamic range (0.007–4.55 mGy s−1). Moreover, the X‐ray sensing efficacies of Eu‐bppCOO‐1 and Tb‐bppCOO‐2 were evaluated, showing that Tb‐bppCOO‐2 features a lower detection limit of 4.06 μGy s−1 compared to 14.55 μGy s−1 of Eu‐bppCOO‐1. Given the higher X‐ray sensitivity and excellent radiation stability of Tb‐bppCOO‐2, we fabricated a flexible scintillator film for X‐ray imaging by embedding finely ground Tb‐bppCOO‐2 in the polydimethylsiloxane (PDMS) polymer. The resulting scintillator film can be utilized for high‐resolution X‐ray imaging with a spatial resolution of approximately 7 lp mm−1. [ABSTRACT FROM AUTHOR]

NaCaYF6 is the formula for gagarinite. Noting the lack of luminescence studies in this material, we synthesized it using the hydrothermal method and investigated the luminescence of several lanthanides. Characteristic luminescence of Eu3+, Dy3+, Sm3+ and Tb3+ was observed. Detailed results on photoluminescence emission and excitation spectra, lifetime, chromaticity coordinates and concentration dependence of emission intensity are presented. Except for Tb3+, which exhibits f-d excitation, the luminescence of other activators got quenched at 1mol % concentration. Eu3+ emission in this host was peculiar, in that the emissions from higher 5D states were observed. Luminescence characteristics are explained using the known energy level diagrams for the lanthanide activators. [ABSTRACT FROM AUTHOR]

A lutetium(III) complex based on the anion of the ligand dimethyl (2,2,2-trichloroacetyl) phosphoramidate (HL) and tetraphenylphosphonium, of composition PPh4[LuL4] (L = CAPh = carbacylamidophosphate), or (C24H20)-[Lu(C4H6Cl3NO4P)4], has been synthesized and structurally characterized. The X-ray diffraction study of the compound revealed that the lutetium ion is surrounded by four bis-chelating CAPh ligands, forming the complex anion [LuL4]- with a coordination number of 8[O] for LuIII, while PPh4+ serves as a counter-ion. The coordination geometry around the Lu3+ ion was determined to be a nearly perfect triangular dodecahedron. The complex crystallizes in the monoclinic crystal system, space group P21/c, with four molecules in the unit cell. Weak hydrogen bonds O⋯HC(Ph), Cl⋯HC(Ph) and N⋯HC(Ph) are formed between the cations and anions. For a comparative study, HL-based structures were retrieved from the Cambridge Structural Database (CSD) and their geometries and conformations are discussed. A Hirshfeld surface analysis was also performed. [ABSTRACT FROM AUTHOR]

A lutetium(III) complex based on the anion of the ligand dimethyl (2,2,2-trichloroacetyl) phosphoramidate (HL) and tetraphenylphosphonium, of composition PPh4[LuL4] (L = CAPh = carbacylamidophosphate), or (C24H20)-[Lu(C4H6Cl3NO4P)4], has been synthesized and structurally characterized. The X-ray diffraction study of the compound revealed that the lutetium ion is surrounded by four bis-chelating CAPh ligands, forming the complex anion [LuL4]- with a coordination number of 8[O] for LuIII, while PPh4+ serves as a counter-ion. The coordination geometry around the Lu3+ ion was determined to be a nearly perfect triangular dodecahedron. The complex crystallizes in the monoclinic crystal system, space group P21/c, with four molecules in the unit cell. Weak hydrogen bonds O⋯HC(Ph), Cl⋯HC(Ph) and N⋯HC(Ph) are formed between the cations and anions. For a comparative study, HL-based structures were retrieved from the Cambridge Structural Database (CSD) and their geometries and conformations are discussed. A Hirshfeld surface analysis was also performed. [ABSTRACT FROM AUTHOR]

Two series of 2-(2-hydroxyphenyl) substituted benzimidazole derivatives, (1-phenyl-2-(2-hydroxy-3-methoxyphenyl)benzimidazole, HL1; 1-methyl-2-(2-hydroxy-3-methoxyphenyl)benzimidazole, HL2) and their bimetallic complexes Zn–Ln(III)–L (Ln = Tb, Nd, Eu and Y) were prepared. The structures of ligands and complexes were characterized by 1H-NMR, FT-IR and single crystal X-ray diffraction. The UV–Visible absorption spectra, emission spectra and luminescent lifetime were measured. These results suggested that the ligands could efficiently sensitize the characteristic luminescence of Tb(III) and the photoluminescence quantum yield(PLQY) for Tb(III) complexes 3 and 7 were 74.8% and 55.3% respectively. While Nd(III) complexes 1 and 5 shown weak emission, and the Eu(III) complexes could not give the typical emission of lanthanide ions maybe due to the photo-induced electron transfer. In addition, the internal quantum yields of Nd(III) complexes were calculated utilizing luminescent lifetime. [ABSTRACT FROM AUTHOR]

The use of lanthanide‐based metallogels presents a promising approach for the engineering of stimuli‐responsive gel materials. Stimuli‐responsive luminescent materials based on lanthanides have promising applications in bio‐applications and optical encoding. Synthetic supramolecular metallogels typically become kinetically trapped and usually do not exhibit time‐variable changes in their material properties. However, such supramolecular metallogels can switch between gel to sol when subjected to different external physical and chemical stimuli. This is because weak noncovalent interactions hold together the gel structure and are also influenced by the coordination dynamics of the metal‐ligand bond. This review summarizes recent research progress on stimuli‐responsive supramolecular lanthanide‐based luminescent metallogels. Chemical, physical, and multiple stimuli‐responsiveness of the metallogels are discussed elaborately based on the external stimulus sources. Finally, the latest challenges and opportunities for developing novel metallogels that respond to stimuli are discussed. [ABSTRACT FROM AUTHOR]