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Four novel compounds {[In­(FDA)­(HFDA)­(H2O)4]­·2H2O} (In1) and {[Ln2(FDA)2­(H2O)10]­·FDA­·6H2O} n (Ln = Dy2, Eu3, Gd4) have been hydrothermally synthesized by using the ligand furan-2,5-dicarboxylic acid (H2FDA). Driven by hydrogen bonding and π···π stacking, In1 displays a supramolecular metal–organic framework (MOF) with 6-connected pcu topology. Isostructural Dy2, Eu3, and Gd4 possess one-dimensional “wave-like” chains and further exhibit bnn topological structures with the Schläfli symbol of (46·64) via a hydrogen bonding network. The triplet state (T1 = 22371 cm–1) of H2FAD studied by compound Gd4 indicates that the energy transition from the H2FDA ligand to the Eu3+ ion in compound Eu3 is efficient but inefficient to the Dy3+ ion in compound Dy2. Interestingly, the uncoordinated carbonyl group of compound In1 can sensitize Ln3+ ions to obtain Dy 3+ @In1 and Eu 3+ @In1 materials for enhancing luminescence. The possible sensitization mechanism is studied by X-ray photoelectron spectroscopy and surface photovoltage spectroscopy. When the Eu3+ ion is increased from 0.0 to 1.6 μM in aqueous solution, compound In1 exhibits a distinguishable luminescence color change from blue to red with a fast detection time (<2 min), and the ratio of luminescence intensity at 617 nm to that at 408 nm (I 617/I 408) enhances linearly with a low detection limit of 0.87 μM. Additionally, with careful adjustment of lanthanide­(III) ions, white-light emission material could be achieved with metal content of Dy0.87Eu0.13.

We report the observation of optically pumped lasing in self-coupled resonators constructed with dye-doped polymer nanowires. Three nanowires with a diameter of 350 nm, 360 nm and 500 nm were fabricated into different self-coupled resonators and single-mode lasing emission was obtained. The self-coupled resonators can be utilized to realize tunable laser systems and enhance the coupling efficiency of emission in ultrasmall resonators.

Drug delivery in target regions could make extraordinary progress in chemoselective therapies. A novel preferred coordination (PC) strategy referring to proactive interacting with open active sites to replace previous occupation by ion-exchange for controlling release of drug molecules is well-constructed. Two topological types of MOF-In1 (Schläfli symbol: (4,8)-connected of (4·6·8)(4·6)) and MOF-In2 (Schläfli symbol: (4,4)-connected of (6)) show the specific way. Increasing node connectivity as well as the trapping of guest OH anions, 5-fluorouracil (5-FU) is preferentially captured into the MOF-In1, which exhibits an outstanding loading capacity around 34.32 wt %. F NMR spectroscopy was further employed to investigate host-guest interaction and reveal the binding constant (K = 3.84 × 10 M). Meanwhile, the controlled release of 5-FU in a simulated human body with liquid phosphate-buffered saline solution by biofriendly Zn-triggered is realized. With an elevated Zn concentration, the drug release will be enhanced. This efficient strategy for MOFs as multifunctional drug carrier opens a new avenue for biological and medical applications.

Humidity-induced single-crystal transformation was observed in the indium metal-organic polyhedra [In(TCPB)]·2HO (In1), where HTCPB is 1,3,5-tri(4-carboxyphenoxy)benzene. When the humidity is above 58% relative humidity (RH) at room temperature, the neutral compound In1 could be successfully converted into the positively charged compound In1-H along with the color change from yellow to deep red, which also undergoes a reversible transformation into In1 driven by thermal dehydration. Notably, the color of In1 takes only 5 min to change under 58% RH at room temperature, which is much quicker than common desiccant bluestone. As the water content is increased from 0.0% to 0.2% in acetonitrile solvent, compound In1 exhibits rapid detection of trace amounts of water through turn-off luminescence sensing mechanism with a low detection limit of 2.95 × 10%. Because of the formation of extensive hydrogen-bonding network between the metal-organic polyhedra (MOPs) and surrounding guest OH ions, compound In1-H, along with isostructural Ga1-H, displays excellent proton conductivity up to 2.84 × 10 and 2.26 × 10 S cm at 298 K and 98% RH, respectively. Furthermore, the activation energies are found to be 0.28 eV for In1-H and 0.34 eV for Ga1-H. This method of incorporation of OH ions to obtain high proton conductivity MOPs with low activation energy demonstrates the advantage of OH ion conduction in the solid-state materials.

Six novel luminescent materials In(III)-2,3-H 2 qldc/phen metal−organic assemblies (MOAs), namely, [In 2 (phen) 3 Cl 6 ]•CH 3 CN (In1), [In 2 (phen) quinoline-2,3-dicarboxylic acid; 3-Hqlc = quinoline-3-carboxylic acid, which is formed from the decarboxylation reaction of 2,3-H 2 qldc; phen = 1,10-phenanthrolin; 2,2′-bipy = 2,2′-bipyridine) have been hydro(solvo)thermally synthesized and characterized by singlecrystal X-ray diffraction, infrared (IR), elemental analysis, 1 H NMR spectra, and thermogravimetric analysis (TGA). The crystal structures of In1−In6 indicate that the hydrogen bonding and π•••π stacking interactions play critical roles in the formation of the extended supramolecular array. In1 displays the rare hexatomic ring 3D (4,5)-connected supramolecular architecture through twofold interpenetrating of 2D cell membrane-like structures. In2 exhibits a 3D 4-connected sra supramolecular architecture. In3 is built from binuclear [In 2 Cl 2 ] clusters and possesses an interesting 2D (4,4)-connected sql supramolecular network. Due to existing hydrogen bonds forming coplanar dimers, In4 and In5 show more extended π-conjugated system and appear as 3D diamond-like supramolecular architectures with point symbol 6 6 . In6 is coordinated with four almost vertical ligands and further form a 3D diamond-like supramolecular architecture via hydrogen bonding and π•••π stacking interactions. Complexes In1−In6 exhibit tunable luminescence with emission maxima containing deep blue, blue, light blue, green, and yellow green at 298 and 77 K both in DMSO solvent and in the solid state. It is worth noting that In4 and In5 exhibit good aggregation-induced emission (AIE) properties in the solid state. Both of them show very weak luminescence in dimethyl sulfoxide (DMSO, good solvent) while their intensity increased enormously by the addition of water (H 2 O, poor solvent) due to aggregation.

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A laser beam was coupled into a tapered optical fiber tip with a diameter of about 2.6 μm, and a 46 μm diameter microsphere was propelled by the outgoing optical pulse. With the change of pulse energy from 1.35 to 7.22 μJ, the calculated average velocity of the driven microsphere varied from 0.38 to 10.68 cm/s. The scanning electron microscope images of the fiber tip show that there is no thermal damage during the experiment.