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CuGeO3, a quasi-one-dimensional S = 1/2 antiferromagnet, is the first inorganic material to display a spin-Peierls transition (SP) in which the lattice of the S = 1/2 antiferromagnetic 1-D chain system undergoes dimerization below the transition temperature to give a singlet ground state. The size-dependent magnetic properties and SP transitions of CuGeO3 are little understood. In this paper, we report the size-controlled synthesis of CuGeO3 nanorods by a hydrothermal method via adjustment of the reaction conditions. The size-effect on their magnetic properties has been investigated. In smaller crystalline CuGeO3 nanorods (ca. 2 μm length) show a weak SP transition. These findings demonstrate that size tuning is an effective tuning parameter for controlling the ground state properties of CuGeO3 and other magnetic materials where spin–lattice interactions are important.

The hierarchical flower-like Bi2MoO6 microstructures have been prepared via a facile solvothermal approach, employing ethylene glycol as the reaction medium in the presence of ethylenediamine. The flake-like building units of the hierarchical, flower-like Bi2MoO6 were constructed by many smaller spherical particles. Reaction temperature, reaction time and the volume of ethylenediamine were studied and found to play crucial roles in the formation of the Bi2MoO6 architectures. A possible mechanism in the formation of the microstructures was proposed based on the results of the morphology evolution as a function of reaction time. The hierarchical flower-like Bi2MoO6 were found to exhibit highly efficient visible-light driven photocatalytic activities for the degradation of rhodamine B (RhB). Comparisons of three Bi2MoO6 microstructures with different morphologies suggest that the morphologies of the products have a great effect on the photocatalytic activities.

We report here the preparation of flower-like Bi2WO6via a simple, rapid, microwave-assisted solution-phase process. Powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), field emission scanning electron microscopy (FE-SEM) and high resolution transmission electron microscopy (HRTEM) were employed to characterize the phase and morphologies of the products. The time-dependent experiments showed an Ostwald ripening mechanism in the crystal growth process. The as-prepared Bi2WO6 was able to efficiently degrade Rhodamine B (RhB) under visible light irradiation. Calcination was found to decrease the photocatalytic performance of flower-like Bi2WO6.

We report here the preparation of self-assembled persimmon-like (BiO)2CO3 microstructures via a simple hydrothermal process. Powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), field emission scanning electron microscopy (FE-SEM), selected area electron diffraction (SAED) and high resolution transmission electron microscopy (HRTEM) were employed to characterize the phases and morphologies of the products. The reactants could greatly influence the phases and morphologies of the final products. The growth process of the persimmon-like (BiO)2CO3 microstructures has been investigated. The persimmon-like (BiO)2CO3 could be utilized as a sacrificial template to synthesize sphere-like Bi2S3 microstructures by a chemical transformation process. The as-prepared (BiO)2CO3 was able to efficiently degrade Rhodamine B (RhB) and eosin sodium salt under simulated solar irradiation.

In the present paper, we report successful synthesis of FeMoO4 hierarchical hollow spheres with 1.0 µm in diameter via a simple, rapid and reliable microwave-assisted solution-phase approach. The phases and morphologies of the products have been characterized by powder X-ray diffraction (XRD), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Some factors influencing the morphology of the final product have been investigated. These experiments indicate that the self-assembly of FeMoO4 nanoparticles at the water/gas interface is responsible for the formation of a hierarchical hollow structure.

A novel mercury iodide adduct [HgI2(4,4′-azpy)]n (4,4′-azpy⊕=⊕4,4′-azopyridine) was synthesized in THF. Single crystal X-ray diffraction analysis shows that it exhibits a zigzag chain structure with distorted tetrahedral Hg centers. Its optical response to incident light shows considerable optical absorptive activity and a strong self-focusing effect with α2⊕=⊕1.3⊕×⊕10−11 m W−1, n2⊕=⊕5.39⊕×⊕10−18 m2 W−1.

Novel pancake-like Cd(OH)2 superstructures have been prepared via a facile and rapid microwave-assisted hydrothermal method, employing cadmium acetate and hydrazine hydrate as the starting materials in a mixed medium of water and glycerol. Several influencing factors, such as the volume of hydrazine hydrate and glycerol, the reaction time, temperature and cadmium source, were found to play important roles in the formation of the Cd(OH)2 multilayer stacked structures. Experiments suggested that the layer-by-layer self-assembly of nanosheets is responsible for the formation of these superstructures. Moreover, the as-obtained Cd(OH)2 superstructures show an enhanced photocatalytic activity for the decomposition of rhodamine B (RhB) under basic conditions.

Monodisperse erythrocyte-like Cd2Ge2O6 superstructures have been successfully prepared via a facile and fast microwave-assisted solution-phase approach, employing Cd(Ac)2·2H2O and GeO2 as the reactants in the presence of hydrazine monohydrate. The phase and morphology of the product were characterized by powder X-ray diffraction (XRD), X-ray photoelectron spectrum (XPS), energy dispersive spectrometry (EDS), selected area electron diffraction (SAED), high resolution transmission electron microscopy (HRTEM) and scanning electron microscopy (SEM). Such monoclinic phase Cd2Ge2O6 microstructures were found to be constructed by abundant single crystalline nanoneedles. Some influencing factors such as the reaction time, reaction temperature, the volume of hydrazine monohydrate and the cadmium source were revealed to play crucial roles in the formation of the Cd2Ge2O6 architecture. A possible growth mechanism was proposed based on the experimental results.

Well-aligned Zn2GeO4 nanorod bundles were successfully prepared via a facile microwave-assisted solution-phase approach. The phase and morphology of the product were characterized by powder X-ray diffraction (XRD), energy dispersive spectrometry (EDS), selected area electron diffraction (SAED), high resolution transmission electron microscopy (HRTEM), and scanning electron microscopy (SEM). Such rhombohedral phase Zn2GeO4 bundle-like microstructures were found to be constructed by abundant single crystalline nanorods of 40–70 nm in diameter and ∼800 nm in length. Some influencing factors such as the reaction time, temperature, the volume of ethylenediamine and PEG-400 were revealed to play crucial roles in the formation of Zn2GeO4 nanobundles. A possible growth mechanism was proposed based on the experimental results. Moreover, the photocatalytic properties of as-prepared Zn2GeO4 nanobundles were studied, and they exhibited excellent photocatalytic activities for degradation of methyl orange and rhodamine B under UV light irradiation.