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For the first time, X-ray excited luminescence of Sr 2 MgSi 2 O 7 :Eu 2+ , Dy 3+ , an efficient persistent phosphor with good potential for lighting, biological imaging and photodynamic activation, is reported in this paper. A modified Sol-Gel method is used to synthesize Sr 2 MgSi 2 O 7 :Eu 2+ , Dy 3+ phosphors and their luminescence properties are highly associated with the synthesis conditions. The dependences of the X-ray excited optical luminescence and persistent luminescence of Sr 2 MgSi 2 O 7 :Eu 2+ , Dy 3+ on the reaction pH, temperature, ratio of Eu/Dy, and the calcination duration time are investigated and the association of the luminescence behaviors with the synthesis conditions is explored as a good strategy to optimize the phosphors for practical applications. [ABSTRACT FROM AUTHOR]

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]