Photocatalytic technology aiming to eliminate organic pollutants in water has been rapidly developed. In this work, we successfully synthesized CuWO 4 /ZnO photocatalysts with different weight ratios of CuWO 4 through facile hydrothermal treatment. Crystal structures, forms, and optical properties of these as-prepared materials were investigated and analyzed. 3% CuWO 4 / ZnO showed the optimum photodegradation efficiency toward methylene blue under the irradiation of simulated sunlight for 120 min, the degradation rate of which was 98.9%. The pseudo-firstorder rate constant of 3% CuWO 4 /ZnO was ∼11.3 and ∼3.5 times bigger than that of pristine CuWO 4 and ZnO, respectively. Furthermore, the material exhibited high stability and reusability after five consecutive photocatalytic tests. In addition, free radical capture experiments were conducted and the possible mechanism proposed explained that the synergistic effect between CuWO 4 and ZnO accelerates the photodegradation reaction. This work provides a feasible technical background for the efficient and sustainable utilization of photocatalysts in wastewater control.

To improve the visible light photocatalytic activity of a ZnIn2S4 sample, we synthesized two kinds of coupled-photocatalysts: TiO2@ZnIn2S4 core-shell type heterostructure composites by a simple and flexible hydrothermal route using TiO2 as the precursor and CuO/ZnIn2S4 contact type heterostructure composites incorporated with different amounts of CuO by the impregnation-calcination method. These as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-Visible absorption spectra (UV-Vis) and nitrogen adsorption measurements. An enhancement in photocatalytic activity was observed after the addition of TiO2 and CuO. It was found that the as-synthesized TiO2@ZnIn2S4 photocatalyst was more efficient than TiO2 and ZnIn2S4 in the photocatalytic degradation of methylene blue (MB). TEM images confirmed that the TiO2@ZnIn2S4 nanoparticles possessed a well-proportioned core-shell morphology. On the other hand, the effects of CuO loading amount on the crystal structure, and photocatalytic properties of CuO/ZnIn2S4 samples for MB degradation under visible light irradiation were investigated, suggesting that the introduction of CuO could influence the morphology and BET specific surface area of the ZnIn2S4 sample and enhance the visible light absorption of photocatalysts. The photocatalytic degradation performance of MB was remarkably improved in the presence of CuO/ZnIn2S4 compared to pure ZnIn2S4 and 10 mol% CuO/ZnIn2S4 was found to possess the optimal photocatalytic performance. Moreover, mechanisms for the enhanced photocatalytic activity of the TiO2@ZnIn2S4 and CuO/ZnIn2S4 composites were proposed.

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Metamaterials consisting of deep subwavelength artificial “atoms” have been utilized to demonstrate a series of novel phenomena such as negative refraction and epsilon‐near‐zero. In recent times, metamaterials have been developed as an up‐and‐coming platform for quantum optics. Here the generation and modulation of photonic entanglement are investigated based on the parametric down conversion processes in metamaterials with considerable optical nonlinearity. Through flexible nanostructure design, the nonlinear photonic interaction in the metamaterial system can be effectively tailored. The distributions of optical parameters of the system are inhomogeneous, based on which the spatial properties of the generated photonic state can be steered as desired. The theoretical framework to describe this system is established based on the nonlinear Huygens–Fresnel principle, and a differential approach is utilized to deal with the intrinsic loss of the system. The generation of orbital angular momentum entangled states is actually considered as an illustration. This platform could be valuable for the practical applications of quantum information processing.

In this study, a novel boehmite/polyacrylonitrile (BM/PAN) composite nanofiber membrane was prepared using the electrospinning technique.