Novel worm-like Ag/ZnO core–shell heterostructural composites were fabricated using a two-step chemical method. As-prepared silver nanowires were soaked in a solution of zinc acetate and triethanolamine to form worm-like Ag/ZnO core–shell composites under ultrasonic irradiation. Samples were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy, and UV–vis spectrophotometer. The results show that the core–shell composites are composed of single-crystal Ag nanowires serving as the core, on which dense ZnO particles grow as the shell. The surface plasmon absorption band of Ag/ZnO composites is distinctly broadened and red shifted to monometallic Ag nanowires. The PL intensity of Ag/ZnO heterostructural composites varies and has the minimum intensity for the sample prepared with Ag of 2.8 atom %. Moreover, photocatalytic tests show that the Ag/ZnO composites exhibit higher photocatalytic activity compared to pure ZnO particles.

In the current research, we have successfully fabricated single-crystalline triclinic Mg 2 B 2 O 5 and orthorhombic Mg 3 B 2 O 6 nanorods by a solvothermal method under supercritical conditions. Detailed microstructures of as-synthesized products were characterized by X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy, and X-ray photoelectron spectroscopy. It was found that the morphology and phase of the products were strongly dependent on the reaction conditions, such as the ratio of Mg/B, temperature, reaction time, and solvent media. The formation process of Mg 2 B 2 O 5 nanorods was illustrated based on SEM observations of the different reaction stages. This technique may also have great potential in realizing other nanostructured materials.

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The electronic parameters of fullerenes are essential for their potentials used as active layers in organic solar cells. Two isomeric forms of the C 60 ([5,6] fulleroid and [6,6] methanofullerene), named [60] PCBM (phenyl-C 61 -butyric acid methyl ester) clusters, were calculated using the B3LYP method with the 6-31G(d) basis set. It has been found that the contraction of C 6-6 double bonds is favorable for addition. The first adiabatic electron affinity (AEA) for [60] PCBM is similar to that for C 60 . The energy gaps between the highestoccupied molecular orbital (HOMO) and the lowest-unoccupied molecular orbital (LUMO) of [60] PCBM have been reduced compared with C 60 . PCBM derivatives show an increased level of LUMO of fullerenes. From the natural charge populations, it has been found that adding a PCBM unit onto the C 60 cages does not change the charge populations remarkably; attaching a PCBM has no effect on the electronic structures of C 60 . The results of theoretical calculation suppose that PCBM is not involved in the process of photoelectric conversion, but it plays a key role in adjusting the level of HOMO-LUMO for increasing photoelectric conversion efficiencies.

Novel flower-like vanadium carbide (V 8 C 7 ) hierarchical nanocrystals have been successfully synthesized in a large-scale hydrothermal process using a mixture of diethanolamine (HN(C 2 H 4 OH) 2 , DEA) and V 2 O 5 powder. The products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), selected-area electron diffraction (SAED) and energy-dispersive spectra (EDS). The results showed that flower-like products consist of very thin sheets with an average thickness of 10 nm and the nanosheets were a uniform single-crystalline V 8 C 7 phase. It was found that reaction temperature and type of capping molecules have a crucial influence on the morphology of the products. A possible growth mechanism of the flower-like V 8 C 7 hierarchical nanocrystals is proposed and discussed.