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Zn1−xFexO films were prepared by the radio-frequency (rf) magnetron sputtering technique on n-Si substrates with a composite target of a ceramic polycrystalline ZnO containing several Fe pieces on the surface. X-ray photoelectron spectroscopy study of the Zn1−xFexO films shows that Fe in the as-deposited film exists mainly in the form of Fe2+. And x-ray diffraction spectra show that all the films exhibited c-axis orientation. The room temperature photoluminescence (PL) properties of the Zn1−xFexO films were also discussed. Two obvious PL peaks appear at 378 nm and 414 nm, respectively. It is interesting that there is a tendency of redshift for the peak at 378 nm and that the PL intensity increases slightly for the peak at 414 nm as the Fe concentration increases. Discussions have been given to explain the different phenomena.

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A facile and general strategy is presented to create well-defined heterojunctions with ultra-small multimetallic sulfide nanoparticles (MMSNPs) uniformly coated on sliver nanowires. A unique aspect of this method is the atomic-level pre-integration of multimetallic components by exploiting recently developed supertetrahedral metal sulfide nanoclusters. The use of such nanoclusters also enables the convenient formation of the ultrathin interfacial Ag S layer via etching. The heterojunctions (denoted as MMSNPs/Ag S/Ag-NWs) benefit from adjustable multimetallic components and display tunable visible-light-driven photocatalytic performance owing to the synergistic effect of multimetallic components from MMSNPs and the high carrier mobility of Ag-NWs. The synthetic strategy opens new routes to designing and fabricating various heterojunctions with multimetallic components, which could further expand their applications in catalysis, electronics, and photonics.

Vanadium dioxide (VO) is a strong-correlated metal-oxide with a sharp metal-insulator transition (MIT) for a range of applications. However, synthesizing epitaxial VO films with desired properties has been a challenge because of the difficulty in controlling the oxygen stoichiometry of VO , where x can be in the range of 1< x < 2.5 and V has multiple valence states. Herein, a unique moisture-assisted chemical solution approach has been developed to successfully manipulate the oxygen stoichiometry, to significantly broaden the growth window, and to significantly enhance the MIT performance of VO films. The obvious broadening of the growth window of stoichiometric VO thin films, from 4 to 36 °C, is ascribed to a self-adjusted process for oxygen partial pressure at different temperatures by introducing moisture. A resistance change as large as 4 orders of magnitude has been achieved in VO thin films with a sharp transition width of less than 1 °C. The much enhanced MIT properties can be attributed to the higher and more uniform oxygen stoichiometry. This technique is not only scientifically interesting but also technologically important for fabricating wafer-scaled VO films with uniform properties for practical device applications.