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Yb3+/Er3+ co-doped yttrium-based coordination polymer (CP) hierarchical micro/nanostructures constructed from well-stacked multilayers have been successfully fabricated on a large scale through a self-assembly process under hydrothermal conditions, among which allantoin with multiple N- and O-donor atoms was employed as an organic ligand. The as-prepared products were well characterized and analyzed. It turns out that the superstructures with well-defined morphology are built from nanoparticles with the size of 40 nm. The nanocrystals aligned with each other resulting in the formation of a multi-layered hierarchical structure. The detailed formation mechanism of the unique CP hierarchical micro/nanostructures was proposed. Moreover, the corresponding Y2O3:Yb3+,Er3+ hierarchical micro/nanostructures were obtained by heating the precursors at 800 °C for 4 h in air. The upconversion luminescence properties of the products were also investigated.

Four kinds of guest-driven lanthanide coordination polymers (CPs) have been synthesized. They have similar formula: [Tb(NPA)3CH3CN]n (1, H-NPA = N-phenylanthranilic acid), {[Tb(NPA)3CH3OH]CH3OH}n (2), [Ln(NPA)3DMF]n (Ln = Tb (3a), Gd (3b), Eu (3c)), and [Tb(NPA)3DMSO]n (4). These complexes were characterized by single-crystal diffraction, PXRD, FT-IR, TGA, DTA, EA, UV-vis spectra and luminescence lifetime measurements. They are all highly thermostable, acid and base resistant. The luminescence quantum yields (QY) of Tb3+ complexes: 1, 2, 3a and 4 are 4.0%, 9.0%, 44% and 46% respectively. Interestingly, there is a drastic change from 4.0% to 46% in luminescence QY by exchanging the coordination solvent, the oscillation of small molecule near the Tb3+ causes the drastic change. Furthermore, the octupolar-like structure of 4 has a high two-photon luminescence.

We synthesized two novel lanthanide doped spindle-like mesocrystals, YF3:Ce,Eu,Gd and YF3:Ce,Tb,Gd (abbreviated as YEG and YTG mesospindles, respectively). Both of them possess paramagnetic and fluorescent properties, and their excellent cyto-compatibility and low haemolysis are further confirmed. Therefore, they could act as dual mode contrast agents for magnetic resonance imaging (MRI) and fluorescence imaging. Furthermore, YEG and YTG mesospindles induce dose and time dependent autophagy by activating the PI3K signaling pathway. The autophagy induced by YEG and YTG mesocrystals is confirmed by enhanced autophagosome formation, normal cargo degradation, and no disruption of lysosomal function. This work is important to illustrate how rare-earth mesocrystals affect the autophagic pathway, indicating the potential of the YEG and YTG mesospindles in diagnosis and therapy.

Highly uniform pancake-like CeOHCO3 hierarchical microstructures have been successfully prepared by a simple gelatin-assisted mixed-solvothermal route. Ceria hierarchical microstructures with similar morphology were obtained after thermal treatment of the CeOHCO3 hierarchical microstructures at 700 °C for 4 h. The CeOHCO3 microstructures can be selectively obtained by varying the composition of solvent, concentration of gelatin and triethylenetetramine (TETA). The as-prepared products were characterized by X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electronic microscope (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM) and selected area electron diffraction (SAED). The possible formation process of the CeOHCO3 microstructures was briefly discussed. Gold coated ceria microstructures were also prepared which show excellent catalytic activity in the conversion of carbon monoxide, the T50 and T90 are at 240 °C and 300 °C, respectively.

This article presents a facile approach about the designed synthesis of one-dimensional (1D) dysprosium-based coordination polymer wires under solvothermal conditions with dysprosium chloride and tributyl phosphate (TBP) as starting materials. The wires are in the length of several hundreds of micrometers and diameter in the range of 0.4–2 μm. Time-dependent results revealed that the coordination polymer wires were not stable and evolved into three-dimensional (3D) flower-like tetragonal DyPO 4 superstructures with the prolonging of reaction time. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), selected area electron diffraction (SAED), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), energy disperse spectroscopy (EDS), thermogravimetric analysis (TG) and differential thermal analysis (DTA) were employed to characterize the samples. Interestingly, with the assistance of lauryl sodium sulfate, rice-like macroporous hexagonal DyPO 4 microstructures with a BET surface area of 2.13 m 2 /g were successfully fabricated. A possible formation mechanism for the morphology evolution of the DyPO 4 superstructures was also discussed. Magnetic measurement revealed that the products were antiferromagnetic.

In this paper, it was demonstrated that Y2O3 microprisms could be prepared by a mixed-solvothermal method with triethylene tetramine as precipitator and sequent heat treatment process. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopic (TEM) and high-resolution transmission electron microscopic (HRTEM) were used to characterize the products. The height of the Y4O(OH)9(NO3) microprisms is about 1.2 μm and the length of the side of the bottom surface is about 0.6 μm. It was found that the composition of solvent, dosage of triethylene tetramine, reaction time and reaction temperature had great effect on the morphologies of the final products. The as-obtained product via solvothermal process, monoclinic yttrium oxide hydroxide nitrate, Y4O(OH)9(NO3), could convert to Y2O3 with the same morphology after annealing at high temperatures. Eu3+ doped Y2O3 microprisms were also prepared and their photoluminescence (PL) properties were investigated. This method may be applied to prepare other rare earth oxides with complex structures.

Several novel cadmium sulfide (CdS) micro/nanostructures, including cauliflower-like microspheres, football-like microspheres, tower-like microrods, and dendrites were controllably prepared via an oxalic acid-assisted solvothermal route using ethylene glycol (EG) and H2O as pure and mixed solvents with different S sources. The as-prepared products were characterized by X-ray powder diffraction (XRD), scanning electronic microscope (SEM) and UV–vis spectrophotometer (UV). It was found that CdS micro/nanostructures can be selectively obtained by varying the composition of solvent, concentration of oxalic acid, and sulfur sources. UV–vis absorption spectra reveal that their absorption properties are shape-dependent. The possible formation process of the CdS micro/nanostructures was briefly discussed. This route provides a facile way to tune the morphologies of CdS over a wide range.

Ultralong helical organosilica nanofibers (length up to millimeter) with ordered helical mesoporous channels are synthesized using achiral cationic surfactant as single-structure-directing agent and anionic citrate as counterions. The surfactant molecules form micelles for silica condensation and the counterions reduce the polarity of the surfactant-silicate micelles via electrostatic balance, leading to the self-assembly and growth of the final product. The detailed mechanistic shape-shifting studies reveal that an entropy increase is the main driving force behind the plastic deformation of the solids.

Superstar: branched concave Au/Pd bimetallic nanocrystals were synthesized in high yield by seed-mediated co-reduction of Au and Pd metal precursors in an aqueous solution at room temperature. The branches are concave and have high-index facets on their surfaces. These nanocrystals show superior electrocatalytic activity for the oxidation of ethanol and highly efficient SERS enhancement.

A simple hard template method has been developed to prepare uniform matchstick-like PbS nanocrystals. The approach combines functionalization of the mesoporous walls and channel surface with thioether groups, adsorption of Pb2+, and heating in an N2 atmosphere at high temperature. The structure, morphology and composition of the nanocrystals have been characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), energy dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). The optical properties of the matchstick-like PbS nanocrystals have been systematically investigated by Raman spectroscopy, UV-visible absorption spectroscopy (UV-vis), and photoluminescence spectroscopy (PL). These results demonstrate that these matchstick-like PbS nanocrystals are single crystals and possess novel optical properties, suggesting that they may have many potential applications. A large blue shift is observed in the photoluminescence spectrum, and this clearly shows the quantum size effects of the matchstick-like PbS . Furthermore, a growth mechanism of the PbS heteronanostructure is proposed.

Here we report sensitive and selective detection of TNT based on plasmonic resonance energy transfer from a gold nanoplasmonic probe to conjugated target TNT molecules, leading to quenching on the Rayleigh scattering spectrum of the probe.

Nanostructures with concave surfaces are not common, and their synthesis is still challenging. In this paper, we have successfully synthesized two kinds of five-fold-twinned Au decahedra and dodecagonal plates by changing the reaction conditions. 40 high-index {221} facets were observed in the concave decahedron. The truncated decahedral gold nanocrystals (NCs) with a large size of 250-350 nm were obtained for the first time, which breaks the assumption that the truncated five-fold-twinned Au nanoparticles (NPs) can only be obtained with a size below 5 nm. The growth mechanism and the evolution process of the gold nanostructures were discussed. This work provides a facile way to synthesize concave decahedra, truncated decahedra and dodecagonal plates with controlled nanostructures.

A fabrication of uniform apple-like LaCO3OH hierarchical nanostructures was achieved by a facile hydrothermal route using gelatin as the reactant and structure-directing agent. The hierarchical nanostructures with diameters of 2–5 μm are built from numerous nanoplatelets with thicknesses of 10–20 nm and lengths of 30–80 nm. Influential factors such as reaction time, reaction temperature, dosage of gelatin and potassium hydroxide were systematically investigated. A dipole-field-driven process was suggested for the formation of the apple-like LaCO3OH hierarchical nanostructures. Strong emission centring at 432 nm was realized in the apple-like LaCO3OH hierarchical nanostructures on excitation with 365 nm ultraviolet light. It turns out that it is easy to tune the luminescent characteristics of the LaCO3OH hierarchical nanostructures in a wide spectral range by simply varying excitation lines or doping concentration of Eu3+ and Tb3+. Particularly, white light emission can be obtained in the Eu3+ and Tb3+ codoped LaCO3OH hierarchical nanostructures on excitation in a wide ultraviolet band.

Ligand-free ZnO nanoparticles with a mean diameter of 100 nm were simply synthesized by solid-state transformation of Zn(II)–organic infinite coordination polymer particles (ICPs) at 550 °C. The well-crystallized ZnO nanoparticles exhibit strong visible emission centred at 600 nm and the emission light clearly appeared under UV light, representing the first example of strong, tunable and stable visible photoluminescence from relatively large ZnO nanoparticles both in solution and in the solid state. ZnO nanoparticles were synthesized by this approach without any surfactant or capping molecules and their visible emission is generally stable and remains almost unchanged while keeping samples in air for at least 3 months. The possible mechanism of strong visible emission was also proposed; oxygen vacancies and surface defects play an important role in the visible emission based on the results of electron paramagnetic resonance (EPR) spectra and decay lifetime curve. ZnO nanoparticles with strong visible emission centred at 500 nm could also be obtained by changing the compositions of coordination polymers. This solid-state transformation method provides a new approach to synthesize stable ZnO nanoparticles with strong and tunable visible emission by using coordination polymers.

Novel rare earth based 4,4′,4′′-benzene-1,3,5-triyl-tri-benzonate (RE-BTB) infinite coordination polymer (ICP) hollow microspheres have been successfully prepared via a facile surfactant-free mixed-solvothermal route, among which Tb-BTB was studied in detail. These as-prepared hollow microspheres using terbium as the central ion have diameters of 260–500 nm. Influential factors such as reaction temperature, reaction time, dosage of reagents, and solvent composition on the morphology and size of the Tb-BTB ICP hollow spheres have been systematically investigated. An inside-out formation mechanism was proposed for the hollow microspheres. The photoluminescence properties of the Tb-BTB hollow spheres have been systematically studied. It turns out that it is easy to tune the luminescent characteristics of the Tb-BTB ICP hollow spheres within a wide spectral range by simply varying the excitation lines or the doping concentration of Eu3+. Interestingly, white-light emission was realized in the Eu3+ doped Tb-BTB hollow spheres.