Single crystalline Zn(2)SnO(4) (ZTO) nanorods 2-4 nm in diameter and around 20 nm in length were successfully synthesized by a simple hydrothermal process with use of hydrazine hydrate as an alkaline mineralizer instead of NaOH or NH(3).H(2)O. By analyzing the UV-vis diffuse reflectance spectrum, the optical band gap (E(g)) of the nanorods was found to be 3.87 eV, which indicates a blue shift of 0.27 eV from that of bulk ZTO (3.6 eV). In situ high-temperature X-ray diffraction was employed to study the thermal expansion coefficient and the variation of lattice parameter with temperature of the product. Furthermore, we discussed the chemical mechanism and key factors to the hydrothermal formation of the sub-5 nm ZTO nanorods.

Novel YVO4:Eu3+@YPO4 core/shell heteronanostructures with enhanced photoluminescence (PL) are proposed in this paper. They were readily formed by hydrothermal epitaxial growth of YPO4 onto YVO4:Eu3+nanocrystals because YPO4 and YVO4 have the same crystal structure and similar lattice parameters. Characterizations by means of X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy prove that the as-synthesized products were not a mixture of YVO4:Eu3+ and YPO4 nanocrystals or YV1−x P x O4:Eu3+ (0 < x < 1) solid solutions, but YVO4:Eu3+@YPO4 core/shell heteronanostructures. The heteronanostructures exhibited much stronger PL than the YVO4:Eu3+ nanocrystals under the same conditions; the optimal heteronanostructures with a YPO4/YVO4:Eu3+ ratio of 1:6 yield a PL intensity 44% higher than that of the YVO4:Eu3+ nanocrystals. The YVO4:Eu3+@YPO4 heteronanostructures have some distinct advantages such as high degree of lattice matching between YVO4 and YPO4. Finally, we discuss the mechanism of their PL enhancement.

A cationic metal−organic framework (MOF) ZJU-48 with one-dimensional pores of about 9.1 × 9.1 Å 2 has been prepared from zinc ions, adenine, and carboxyl ligands. ZJU-48 displays excellent water stability for about one week, exhibiting its potential application for adsorption and separation of dyes. Cationic and anionic dyes with similar sizes are adopted to study the adsorbing and separating properties of ZJU-48. Cationic dyes are adsorbed better than anionic dyes because of the negatively charged zeta potential of the material surface, implying its selective adsorption to cationic dyes, and it is charge-based adsorption. Meanwhile, the adsorption ability of the MOF to cationic dyes with different sizes is also investigated. We find that the adsorbed amount decreases with increase in the size of organics ,indicating that it is sizebased adsorption. Furthermore, the cationic dye methylene blue (MB) is employed and focused on for its suitable charge and fitting size to evaluate the maximum adsorption capacity and desorption progress of ZJU-48. The results show that the maximum loaded amount of MOF toward MB reaches 582.44 mg/g, and about 90% of loaded dyes can be released from frameworks in N,N-dimethylformamide with NaCl over 6 h, exhibiting satisfactory adsorptive property and possibility as a reusable adsorbent.

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Porous zinc ferrite (ZnFe(2)O(4)) nanorods with a diameter of around 50 nm and a length of several micrometers have been synthesized by a microemulsion-based method in combination with calcination at 500 °C. The morphology and structure of the ZnFe(2)O(4) nanorods and its precursor (ZnFe(2)(C(2)O(4))(3) nanorods) were systematically characterized by x-ray powder diffraction, transmission electron microscopy, field emission scanning electron microscopy and high-resolution transmission electron microscopy. The formation mechanism for the porous ZnFe(2)O(4) nanorods is also discussed. Moreover, the porous ZnFe(2)O(4) nanorods were applied in a room-temperature ethanol sensor and exhibited much better sensing performance than ZnFe(2)O(4) nanoparticles.

Polytetrafluoroethylene (PTFE) porous membranes are widely used for high-temperature filtration.