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Without any catalysts-assisted, homobranched ZnO nano/microstructure had been synthesized via a simple low temperature water bath method. Such nano/microstructure which consists of shuttle-like nano/microrod backbone was surrounded by six radial oriented branches. The length of the shuttle-like ZnO nano/microrods is about 5–10 μm. The diameter of the single shuttle-like nano/microrods is 1–2.5 μm at the stem and 10–50 nm at the tip while the branches size from top to bottom is 10–50 nm to 0.5–1 μm. A strong ultraviolet emission and weak deep level emission reflect the high optical quality. In addition, a detailed discussion regarding the probable growth mechanism is presented in this work. [ABSTRACT FROM PUBLISHER]

Aiming to modification the surface optical properties, CdS/ZnO composites were synthesized by hydrothermal method. The ZnO/CdS heterostructures were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray energy dispersive spectroscopy (EDS), photoluminescence (PL) measurements at room temperature and the temperature-dependent photoluminescence treatment. In the room temperature PL spectra, the defect-related deep level emission can effectively suppress under optimal CdS deposition condition. With the increasing of CdS deposition time to 150 min, the donor bound exciton (D0X) peak showed a significantly red shift at low temperature (77K) PL spectrum. Through analysis the temperature-dependent photoluminescence spectra, we find that it was caused by acceptor bound exciton (A0X). Meanwhile, there appeared a donor-acceptor pair related emission at lower-energy side of the spectrum. The experiment demonstrated that the surface donor defects can effectively suppresse after CdS nanoparticles deposition on ZnO nanorods. [ABSTRACT FROM PUBLISHER]

As a kind of semiconductor material, the morphology of zinc oxide directly affects its physical properties. By adjusting the ratio of the reaction source and the rate of the incoming gas flow, we obtained one-dimensional nanowire and two-dimensional nanoflag-like functional gradient material (FGM) using chemical vapor deposition (CVD) method. Compared with the one-dimensional nanowires, the growth of the two-dimensional ZnO FGM not only c-oriented, but other directions are also appeared. Photoluminescence results show that the FGM has a higher visible/UV emission intensity ratio than the nanowires for several orders of magnitudes. Meanwhile, the growth mechanism of these nanostructures were discussed in details. [ABSTRACT FROM AUTHOR]