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Abstract: SiC/ZnO nanocomposites were synthesized via a two-stage process. SiC nanoparticles were synthesized by electrical explosion method, and using the SiC nanoparticles as precursor, SiC/ZnO nanocomposites were synthesized by co-precipitation processes. The SiC/ZnO nanocomposites exhibit energy tuning of band-to-band transitions. In addition to the UV emission, the green and orange emissions were also observed. To our interest the green and orange emissions decreased at first and then increased with increasing annealing temperature. The underlying mechanism is elucidated. [Copyright &y& Elsevier]

Abstract: A novel core–shell structure material, Cu–Zn/ZnO, was prepared by a surface modification precipitation process in aqueous solution at low temperature. A nucleation and crystal growth model for this structure was proposed. The resultant nanocomposites were characterized by X-ray diffraction, transmission electron microscope, field emission scanning electron microscope and photoluminescence spectroscope. Results showed that 20–50nm thick ZnO shell was obtained on the surface of Cu–Zn nanopowders directly in the aqueous solution at 40°C during the precipitation process and as-synthesized materials have a strong ultraviolet luminescence peak around 379–390nm, but no usual defect-related emissions in visible range. The quantum confinement effect of ZnO nanocrystals, the presence of Cu and Zn atoms and absence of defects in ZnO layer are believed responsible for the characteristics of the photoluminescence spectra. [Copyright &y& Elsevier]

Abstract: The composites of hollow glass microspheres (HGMS) coated by zinc oxide (ZnO) nanorods (HGMS/ZnO) were obtained by the controlled doubled-jet precipitation method in an ethanol–water solution. The particle-size, morphology, crystal structure and optical properties of the as-prepared HGMS/ZnO composites were investigated by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and room-temperature photoluminescence (PL) spectra. Moreover, we propose the mechanism that the hollow glass microspheres are modified with triethanolamine to obtain ZnO-coated composites. This method can also be applied to other substrates forming continuous films with highly ordered ZnO nanorods across the films. [Copyright &y& Elsevier]