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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]

Dy-Bi co-doped yttrium tungstate crystal materials were synthesized by high temperature solid-state method. To reveal the photoluminescence features and properties of the samples, some measurements have been taken. It turned out that different Bi concentrations play obvious influence in emission performance, and show visible light emission under ultraviolet light excitation. Besides, the effect of temperature on phase structure of samples has also been studied here. Superhigh X-ray luminescence of the phosphors exhibited the promising application in the field of high energy detection. The X-ray irradiation crystal resistance stability of the phosphors has also been investigated through the subsequent testing of XRD and spectra. [ABSTRACT FROM AUTHOR]

The phosphors BiPO:Eu co-doped with Dy were synthesized by the conventional solid-state reaction method. XRD and scanning electron microscopy results showed that the crystalline phase of the samples BiPO:Eu transforms from high-temperature monoclinic phase to low-temperature monoclinic phase with the increase of Dy concentration. The photoluminescence properties of the samples showed that the colors shifting from red-orange area to blue-green area are close to those of ideal white light by readjusting the doping concentration ratio of Eu and Dy. The Euand Dy doped BiPO phosphors may be potential applications in white light near-UV light-emitting diodes. [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]

The tunable emission characteristics of Er3+ doped and Er3+/Eu3+ co-doped Na 5 La(MoO 4) 4 phosphors prepared via high-temperature solid phase method were investigated. The microstructure of the modified phosphor was studied by X-ray diffraction, X-ray photoelectron spectroscopy and scanning electron microscopy, and its luminescence properties were analyzed by photoluminescence excitation and photoluminescence spectra. The energy transfer mechanism of Er3+ ions to Eu3+ ions was investigated by changing the concentration of Eu3+ ions to induce the spectral changes, and the photoluminescence decay lifetime was measured to validate the findings. Notably, under excitation at 380 nm, the co-doped phosphors exhibited tunable emission ranging from green to orange-red. Furthermore, Na 5 La(MoO 4) 4 :0.04Er3+/0.04Eu3+ phosphor, when combined with a 380 nm chip, achieved desired warm white light emission. These promising results underscore the potential application of Na 5 La(MoO 4) 4 :0.04Er3+/0.04Eu3+ phosphor in solid-state lighting. [ABSTRACT FROM AUTHOR]

The Sm3+ and La3+ co-doped Na 5 Y(MoO 4) 4 orange-red phosphors were synthesized by solid phase method at 600 °C. The crystal structure, phase purity, thermal stability, and luminescence performance were comprehensively analyzed. Under 405 nm excitation, the phosphors emit the orange-red light because of the 4G 5/2 -6H 5/2 , 4G 5/2 -6H 7/2 , 4G 5/2 -6H 9/2 , and 4G 5/2 -6H 11/2 transitions of Sm3+ ions. The enhancement of emission intensity with La3+ ions doping in phosphors is due to the environmental effect of the crystal field around the luminous center. When it is combined with commercial LED chips, the device emits orange-red light, and the luminescence spectrum coincides with the PR pigment absorption spectrum of the plant, indicating that the potential of Sm3+ and La3+ co-doped Na 5 Y(MoO 4) 4 phosphors in solid-state lighting application. • The Na 5 Y 0.89 La 0.05 (MoO 4) 4 :0.06Sm3+ phosphors is thermally stable, which is suitable for the preparation of LED. • The emission of Na 5 Y(MoO 4) 4 :Sm3+ phosphor was enhanced by the introduction of La3+. • At 405 nm excitation, Na5Y(MoO4)4:0.06Sm3+ phosphors emit orange-red light, and the electroluminescence spectrum of Na 5 Y 0.89 La 0.05 (MoO 4) 4 :0.06Sm3+ shows the emission spectra at 550–700 nm coincide with the PR absorption spectra, indicating that the device has potential application in plant cultivation. [ABSTRACT FROM AUTHOR]

Highlights • An ultraviolet emitting ceramic substrate is synthesized using phosphors and kaolin. • Photons passing through the TiO 2 layers can be used to re-excite the TiO 2. • Photon utilization and thus the photocatalytic efficiency of TiO 2 are improved. Abstract Titanium dioxide (TiO 2) which could photocatalytically decompose organic pollutants in water, is deposited on an UV emitting substrate which is made from Ca 2 MgSi 2 O 7 :Ce3+ phosphors, for the purpose of better photon utilization and prevention of the suspension forming. The TiO 2 powder distributes homogeneously on the substrate, which could absorb the photons passing through the TiO 2 layer and generate a secondary emission with wavelength of 380 nm. This secondary emission could excite the TiO 2 again, and then promote the photocatalytic efficiency to organic dyes degradation because of the improvement of photon utilization. [ABSTRACT FROM AUTHOR]

Highlights: [•] Single Bi3+ and Dy3+ co-doped YBO3 phosphors at low temperature (900°C) are prepared. [•] The energy transfer from Bi3+ to Dy3+ is dependent on the concentration of Bi3+ ion. [•] The spectrum overlaying provides condition to the resonance energy transfer. [•] The luminescence of Bi3+ and Dy3+ co-doped YBO3 phosphors were reported. [ABSTRACT FROM AUTHOR]