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A series of Sr3Gd1−xLi(PO4)3F: xSm3+ (x = 0.02, 0.04, 0.06, 0.08) phosphors were synthesized by a high-temperature solid state method. The Sm3+ activated Sr3GdLi(PO4)3F phosphors can be efficiently excited by the wavelengths in the range from 350 to 450 nm, which matches perfectly with that of the commercial near-UV LED chips. The optimal doping concentration of Sr3Gd1−xLi(PO4)3F: xSm3+ phosphors was determined to be x = 0.04, corresponding to the quantum efficiency of 2.23%, and the CIE chromaticity coordinates (x = 0.5172, y = 0.4641). The concentration quenching mechanism of Sm3+ in Sr3GdLi(PO4)3F host is mainly attributed to the dipole-dipole interaction, which was confirmed by the fluorescent lifetimes. The effect of temperature on the photoluminescence property of Sr3GdLi(PO4)3F: Sm3+ was investigated. 90% of the intensity is preserved at 150 °C. In addition, a white light emitting diode (WLED) lamp was fabricated by a 405 nm n-UV LED chip coated with Sr3Gd0.96Li(PO4)3F:0.04Sm3+ phosphor and commercial yellow phosphor (YAG: Ce3+) of a certain mass ratio. The present work indicates that the Sr3GdLi(PO4)3F: Sm3+ orange-red-emitting phosphors tend to be potential application in n-UV WLED. [ABSTRACT FROM AUTHOR]

Inverted polymer solar cells of the conventional poly(3-hexylthiophene) (P3HT):(6,6)-phenyl-C61butyric acid methyl ester (PCBM) blend on indium tin oxide substrates were fabricated. By using mixed-solvent dispersed ZnO nanoparticles (NPs) as cathode buffer layer, device performances are improved obviously. ZnO NPs with a size of 3-5 nm synthesized by solvothermal synthesis at 65 °C show relatively wide photoluminescence peak of 300-650 nm. Based on Hansen solubility parameter theory, a mathematical method was applied to calculate the Hansen solubility parameters of bi-solvent system to disperse ZnO NPs and the proportion of each component in the mixed solvent. This excellent dispersion for ZnO NPs in the bi-solvent system has a important influence on the performance of the device. Compared to other methods of ZnO nanofilm fabrication, this method reveals a simple, convenient, moderate and effective way to manufacture the favorable buffer layer in organic solar cells. [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]