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Abstract Zn 1-x WO 4 :xLi+ (x = 0, 0.02, 0.05, 0.1) phosphors were synthesized by high-temperature solid-state method. The structural and luminescence properties of the samples were investigated through X-ray diffraction (XRD), scanning electron microscopy (SEM), Microconfocal Raman spectrometer(MR), Diffuse reflectance spectra (DRS) and Photoluminescence spectra. The Li-doped ZnWO 4 phosphors show photoluminescence with a broad band. Compared with the pure ZnWO 4 , the band gap of lithium doped samples shows a red shift measured by Diffuse reflectance spectra (DRS), which could be attributed to the doping effects. Moreover, photocatalytic activity test shows that the Li-doped ZnWO 4 phosphors exhibit higher catalytic activities than the pure ZnWO 4 for the degradation of Rhodamine B by the UV irradiation. The result shows that the Li-doped phosphors can enhance light harvest capability to generate more electron-hole pairs, and act as a trap center by decreasing the recombination of photogenerated electrons and holes. [ABSTRACT FROM AUTHOR]

Abstract Ti4+-doped ZnWO 4 phosphors were synthesized by a facile solid state reaction route. The structural and morphological features of the as-synthesized Ti4+-doped ZnWO 4 photocatalysts were intensively characterized by XRD(X-ray diffraction), XPS(X-ray photoelectron spectroscopy), UV–vis DRS(Ultraviolet-visible diffuse reflectance spectrum), PL(photoluminescence spectroscopy). The photocatalytic reaction tests have been decomposed by the solution of rhodamine B(RhB). The results showed that the Ti4+ -doped ZnWO 4 phosphors had a high photocatalytic activity, and RhB degradation rate of 97% within 120 min was achieved for the 0.01Ti4+-doped sample. The enhancement of photocatalytic performance for Ti4+-doped ZnWO 4 samples can be ascribed to reduce the recombination rate of photogenerated electron-hole pairs with the formation of new defects by Ti4+ doping. This study suggests that Ti4+-doped ZnWO 4 photocatalysts are promising for photocatalytic decomposition of organic contaminants. [ABSTRACT FROM AUTHOR]

Dual-functional ZnWO4:Dy3+, Bi3+ were synthesized via high-temperature solid-state reaction method. The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), photoluminescence spectra and photocatalytic properties. The ZnWO4:Dy3+, Bi3+ phosphor shows photoluminescence with a broad band and the feature Dy3+ emission, and a high photocatalytic activity in degradation of Rhodamine B (RhB) under simulated UV irradiation. The result shows that doping Bi3+ in ZnWO4:Dy3+ can enhance light harvest capability to generate more electron-hole pairs, and acted as a trap center by decreasing the recombination of photogenerated electrons and holes. All of the results obtained by the work suggest that ZnWO4:Dy3+, Bi3+ phosphors are promising materials for the photocatalytic decomposition of pollutants. [ABSTRACT FROM AUTHOR]