Chiral lanthanide cages with circularly polarized luminescence (CPL) properties have found potential application in enantioselective guest recognition and sensing. However, it still remains a big challenge to develop a simple and robust method for the diastereoselective assembly of homochiral lanthanide cages in view of the large lability of the Ln(III) ions. Herein, we report the first example of the formation of a enantiopure lanthanide tetrahedral cage via a chiral ancillary ligand induction strategy. One such cage, (Eu 4 L 4 )(R/S-BINAPO) 4 , is assembled by four achiral C 3 -symmeric tris(βdiketones) (4,4′,4″-tris(4,4,4-trifluoro-1,3-dioxobutyl)triphenylamine, L) as faces, four Eu(III) ions as vertices and four chiral R-/S-bis(diphenylphosphoryl)-1,1′-binaphthyl (R/S-BINAPO) as ancillary ligands. X-ray crystallography and NMR and CD spectra confirm the formation of a pair of enantiopure chiral topological tetrahedral cages, (Eu 4 L 4 )(R-BINAPO) 4 and (Eu 4 L 4 )(S-BINAPO) 4 (ΔΔΔΔ-1 and ΛΛΛΛ-1). As expected, the tetrahedral cages present strong CPL with |g lum | values up to 0.20, while they unexpectedly give ultrahigh luminescent quantum yields (QYs) of up to 81%, the highest value reported in chiral Ln(III) complexes. More impressively, the chiral memory effect for a lanthanide-based assembly is observed for the first time. The chirality of the original cage 1 framework is retained after R/S-BINAPO is replaced by the achiral bis[2-(diphenylphosphino)phenyl] ether oxide (DPEPO), and thus another pair of enantiopure Eu(III) tetrahedral cages, ΔΔΔΔand ΛΛΛΛ-[(Eu 4 L 4 )(DPEPO) 4 ] (ΔΔΔΔ-2 and ΛΛΛΛ-2), have been isolated. Encouragingly, cage 2 also presents an impressive luminescence quantum yield (QY = 68%) and intense CPL (|g lum | = 0.11). This study offers a simple and low-cost synthesis strategy for the preparation of lanthanide cages with CPL properties.

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A white-light-emitting Eu(iii) coordination polymer based on a 1,8-naphthalimide-derivative was synthesized, and three primary colours are well balanced by controlling energy transfer efficiency from fluorophore to Eu(iii) ions.

Because of the involvement of the gas–solid diffusion, device fabrication, and the relatively complex photophysical process, the lanthanide complexes are rarely exploited as fluorescence sensors for volatile compound (VC) detection. Herein, we report the first example of a discrete 3D Ln-based architecture as a sensor for VCs. The designed Eu4L4 tetrahedral cage shows highly selective, rapidly reversible, and turn-on emissive responses toward volatile amines/NH3 in a spin-coated film. Through the comprehensive spectral characteristic and density functional theory calculation, an intermolecular weak nucleophilic interaction is proposed for this response mechanism. Combining this weak interactions with the permeability of the cage, the film presents subsecond to second timescales rapid response; combining the fitting electrophilic capability of the β-diketonate units to amine nitrogen with the tunable intramolecular charge-transfer feature, the cage shows excellent selectivity and turn-on emissive response. This work provides a new clue to develop the lanthanide complexes as luminescence probes for VCs.

Solubilities of 2-benzoyl-3-chlorobenzoic acid and 1-chloroanthraquinone in organic solvents of ethyl acetate, acetone, 1,4-dioxane, and toluene were determined experimentally in the temperature range from (273.15 to 323.15) K by gravimetric method. The experimental results indicate that the solubility of 2-benzoyl-3-chlorobenzoic acid and 1-chloroanthraquinone in the solvents increased with an increase in temperature. The solubility data of 1-chloroanthraquinone in the different solvents accord with the following order toluene > ethyl acetate > 1,4-dioxane > acetone, whereas for 2-benzoyl-3-chlorobenzoic acid the order is toluene > 1,4-dioxane > ethyl acetate > acetone. The experimental data were correlated with the modified Apelblat equation, λh equation, Wilson model, and NRTL model. The correlation results with the modified Apelblat equation, the λh equation, and NRTL model are better than those with the Wilson model. The enthalpy, entropy, and the change of Gibbs free energy of 2-benzoyl-3-chlorobenzoic acid and 1-chloroanthraquinone in the selected organic solvents were calculated from the measured solubility data by using the modified van’t Hoff equation. The experimental data and model parameters would be useful for optimizing the preparation and purification process of 1-chloroanthraquinone and 2-benzoyl-3-chlorobenzoic acid in industry.

In the present work, h‐RFeO3 multiferroic ceramics are designed and created by introducing chemical pressure (In‐substitution for Lu) in LuFeO3. Lu1−xInxFeO3 (x = 0‐0.75) ceramics are prepared by the standard solid‐state reaction process. The crystal structure of the present ceramics is tuned from centrosymmetric Pbnm (x = 0) to non‐centrosymmetric P63cm (x = 0.4–0.6), and subsequently to centrosymmetric P63/mmc (x = 0.75), while the Pbnm and P63cm biphase structure is detected for x = 0.25. The Curie temperature for the polar P63cm (x = 0.4–0.6) phase decreases from >1000 to ≈550 K with increasing x. Cloverleaf ferroelectric domain structures are determined in polar Lu0.5In0.5FeO3 samples, and the ferroelectric domain walls at atomic scale are evaluated by the aberration‐corrected high‐angle annular dark‐field scanning transmission electron microscopy (HAADF STEM), where the spontaneous polarization of 1.73 µC cm−2 is determined for x = 0.5. The spontaneous polarization is also confirmed by calculating the site displacement from the centrosymmetric phase based on the X‐ray diffraction (XRD) data. Meanwhile, two magnetic transitions are determined for all compositions, that is, paramagnetic to antiferromagnetic transition at Néel temperature TN (≈350 K for x = 0.4–0.6), and antiferromagnetic to weak‐ferromagnetic transition at spin‐reorientation temperature TSR. The co‐presence of ferroelectric and antiferromagnetic orders confirms the present ceramics as promising room‐temperature multiferroic materials.

Chiral lanthanide helical architectures have received intense attentions in recent years because of their potential applications as chiral probes and sensors and as circularly polarized luminescence (CPL) materials. However, stereoselectivity control in the self-assembly of lanthanide helicate is challenging due to the poor stereochemical preference and variable coordination numbers of Ln(III) ions. Herein, we reported the employing chiral ancillary ligand R/S-BINAPO to induce achiral tripodal ligand to form a pair of homochiral lanthanide triple-helical podates [Eu(TTEA)((R/S)-BINAPO); R/S-1] {(R/S)-BINAPO = ( R/ S)-2,2'-bis(diphenylphosphoryl)-1,1'-binaphthyl; TTEA = tris[(4-(4,4,4-trifluoro-1,3-dioxobutyl)-benzamido)ethyl]amine}. X-ray crystallographic analysis for rac-1 reveals that the chirality of BINAPO is transferred during the self-assembly process to give either P or M helical architectures in podates. The H andP NMR and circular dichroism measurements confirm the diastereopurity of the assemblies in solution. A detailed optical and chiroptical characterization reveals that the luminescent enantiopure podates not only exhibit intense CPL with | g| values reaching 0.072 but also show high luminescence quantum yields of 32.8%. Our results provide a feasible strategy for designing homochiral helical lanthanide supramolecular architecture and synthesizing excellent CPL materials.

The aim of this study was to present a non-trypsin 3D cell culture method with a reversible thermosensitive HBCS hydrogel. In this study, hydroxybutyl chitosan (HBCS) was synthesized by grafting hydroxybutyl groups on chitosan molecule chains. The prepared HBCS was water-soluble, and the reversible phase transformation temperature was 26 °C. Scanning electron microscope images illuminated the 3-D network of hydrogel formed irregular porous structure which ranged from 50-250 μm. Cell viability assay indicated that HBCS solution could promote the proliferation of human umbilical vein endothelial cells (HUVECs), and the boost of proliferation was enhanced with the increase of HBCS concentration. HBCS had no harm to the nitric oxide (NO) synthesis functionality of HUVECs. HUVECs could grow and reproduce inside the hydrogel, and showed good vitality after 14-days culture. Meanwhile, cells cultured inside the hydrogel could be passaged successively through the reversible phase transformation process of HBCS. The results revealed that HBCS have the potential to be used for 3-D cell culture without the use of trypsin.