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Well-dispersed hollow CeVO4 microspheres with tunable hollowness and porosity have been synthesized via a simple hydrothermal method using L-aspartic acid (L-Asp) as the capping agent. The products were characterized by XRD, SEM, TEM and DRS. The XRD results showed that the as-prepared samples were tetragonal phase CeVO4 with high crystallinity. SEM and TEM observations indicated that the hierarchical hollow microspheres with different hollowness were constructed from nanoparticles, cubes or nanoflakes. N2 adsorption–desorption measurements revealed that the BET specific surface area of the typical CeVO4 hollow microspheres was up to 106.54 m2 g−1. During the synthesis, the amount of L-Asp and the reaction time were found to play important roles in determining the growth process and final morphologies of the CeVO4 products. Time-dependent experiments clearly revealed that the CeVO4 hierarchical hollow microspheres were governed by the self-assembly and Ostwald ripening process. Rhodamine B (RhB) was used as the dye pollutant for evaluating the photocatalytic properties of the products under UV radiation. The CeVO4 hierarchical hollow microspheres exhibited excellent photocatalytic activity and good stability even after five repeated cycles of use, indicating that the CeVO4 hierarchical hollow microspheres can be good candidates for photocatalytic degradation of organic pollutants.

Based upon the typically hydrogen-bonded network, metal–organic cubes, the amino functional group was first introduced onto the surface of the cube to raise the polarizability of the framework by in situ hydrolysis of the precursor 2-amino-4,5-dicyanoimidazole (ADCIm) with octahedral In3+ ions under solvothermal conditions, resulting in a supramolecular network with very high CO2 (135.8 cm3 g−1 at 273 K/1 atm) and H2 (2.03 wt% at 77 K/1 atm) adsorption capacities and an exceptional thermostability range up to 416 °C.

A novel porous coordination polymer based on a Co-nitroimidazolate–dicarboxylate pillared-layer network, namely, [Co7(bdc)6(nIm)2(H2O)6]·3H2O·3DMF, (1, H2bdc = 1,4-benzenedicarboxylic acid, nIm = 2-nitroimidazole), has been synthesized by a solvothermal reaction. The microporous layers of 1 consisted of two kinds of SBUs, six-connected Co3(O2CR)6 and three-connected [Co2(O2CR)3]+, forming unprecedented Co3-Co2-bdc-based layers with three types of diamonded grids in the bc plane. The layers are further linked by bidentate-bridging nIm ligands as pillars into a 3-D metal–organic framework with two kinds of rectangular channels parallel to the c axis. It is worth mentioning that compound 1 also exhibits uniquely polyhedral cages with a maximum diagonal dimension of up to 31.019 A, which has fallen in the scope of mesoporous (2–50 nm). To systematically evaluate the channels and special cages, the adsorption ability of 1 was measured by N2, H2 and CO2 sorption experiments. Topological analysis indicates that compound 1 adopts a new topological structure with a point symbol of {412·614·82}{46}2. Moreover, thermal gravimetric analysis (TGA) of as-synthesized 1 reveals a stability range up to 311 °C.

Novel yolk–shell ZnWO4 microspheres have been fabricated via a one-pot hydrothermal process in the presence of L-aspartic acid (L-Asp). The as-obtained products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, nitrogen adsorption–desorption experimentation and UV-vis absorption spectroscopy. The effects of the reaction conditions on the morphology and crystallinity of the products were studied, as well as the amount of L-Asp, reaction time and reaction temperature. As the chelating agent and shape modifier, L-Asp plays a key role in the crystal growth of the yolk–shell ZnWO4 microspheres. A possible formation mechanism for the yolk–shell microspheres is proposed. The photocatalytic properties of the yolk–shell ZnWO4 microspheres were investigated by the decomposition of Rhodamine B (RhB) and methylene blue (MB) under UV light irradiation and the results show that they have excellent photocatalytic activities. Furthermore, the obtained yolk–shell ZnWO4 microspheres are chemically stable and the efficiency remained almost the same after being recycled five times, suggesting that the yolk–shell ZnWO4 microspheres are promising photocatalysts for practical applications.

There are rare reports of high-nuclear transition metal clusters with thiol groups in their periphery. In this work, a novel cluster, [Fe6O2(OH)2(O2CC6H4SCH3)10(hep)2]·CH3CN·CH2Cl2 (Fe6) has been constructed by coordinating an octahedral Fe(III) ion with 4-mercaptobenzoate and hepH (hepH = 2-(2-hydroxyethyl) pyridine). The functionalized thiomethyl groups around the periphery of the Fe6 cluster may provide binding sites for the surfaces of some specific materials, such as noble metals. Therefore, silver nanoparticle coated Fe6 (Ag@Fe6) complexes have been prepared by spontaneous self-assembly reactions. Transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM) images show that the Fe6 cluster layer is formed on the surface of the silver nanoparticles and the diameter of the Fe6 cluster is about 2 nm. In addition, powder X-ray diffraction (XRD), UV-vis spectroscopy, surface enhanced Raman spectroscopy (SERS), and cyclic voltammetry of the Fe6 and Ag@Fe6 complexes were also investigated.

3D hierarchical ZnOHF nanoflowers with mean diameter of 200 nm have been synthesized via a simple template-free hydrothermal route by using (NH4)2SiF6 as the fluoride source. The crystalline phase and morphologies of the as-prepared products have been characterized by XRD, SEM and TEM. The XRD results show that the products are well-crystallized orthorhombic phase of ZnOHF. The SEM and TEM results indicate that the ZnOHF nanoflowers are assembled by numerous nanoflakes with mean thickness of 20 nm. Some factors influencing the morphologies of the ZnOHF nanostructures have been systematically investigated, such as the reaction time, temperature and fluoride source. A growth mechanism is proposed on the basis of a series of time-dependent morphological evolution results. The hierarchical ZnOHF nanoflowers exhibit a high specific surface area up to 97.1919 m2 g−1 with a pore size of 50.098 nm. The as-obtained ZnOHF can be transformed into ZnO nanoflowers by calcination in air at 600 °C. The photocatalytic properties of ZnOHF have been studied by the decomposition of methyl orange (MO) under UV light irradiation. The results indicate that the flower-like ZnO nanostructures are chemically stable, and the efficiency remained almost the same after five times recycling.

Without any templates or surfactants, large-scale 3D persimmon-shaped hierarchical LaF3 and LaF3:Ln3+ (Ln = Eu, Tb) have been synthesized via a simple hydrothermal route using organic tetrafluroborate complexes N(C4H9)4BF4 as the fluoride source. The phase and morphology of the products have been characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED). The SEM and TEM results indicate the 3D persimmon-shaped hierarchical microstructures are constructed by numerous nanodisks with mean thickness of 50 nm. It is found that several factors, including the fluoride sources, molar ratio of reagents and the reaction time, play crucial roles in the formation of the multilayer stacked structures. Detailed studies indicate that the layer-by-layer self-assembly of nanodisks is responsible for the formation of 3D hierarchical structures. The possible mechanism of the crystal growth and assembled procedure are also proposed. Furthermore, the photoluminescent properties of LaF3:Ln3+ (Ln = Eu, Tb) are studied, which exhibit orange-red (Eu3+:5D0–7F1,2,3,4) and green (Tb3+, 5D4–7F3,4,5,6) emission, respectively.