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A series of single-component Sr3Lu(PO4)3:Eu2+,Mn2+ phosphors were successfully synthesized by solid-state reaction, and their photoluminescence properties were investigated. The Sr3Lu(PO4)3:Eu2+,Mn2+ phosphor system was efficiently excited at wavelength ranging from 250 to 420 nm, which is well-matched with ultraviolet (UV) light-emitting diode (LED) chips. As a result of fine-tuning of the emission composition of the Eu2+ and Mn2+ ions, warm white light emission can be realized by combining the emission of Eu2+ and Mn2+ in a single host lattice under UV light excitation. Efficient resonant energy transfer from the Eu2+ to Mn2+ ions was demonstrated to be a dipole–quadrupole mechanism in such system, and the energy transfer efficiency increases with an increase in the Mn2+ doping content, which was confirmed by the luminescence spectra and fluorescence decay curves. In addition, the energy transfer efficiency and critical distance were also calculated. The results indicate that the developed phosphor can ...

BaYF5 nanocrystals with a mean size of about 24 nm have been prepared via a facile hydrothermal method without the assistance of any surfactant for the first time. The structure investigation reveals that the as-synthesized BaYF5 nanocrystals are cubic structures instead of the reported tetragonal structures found via a Rietveld refinement method with GSAS, a Rietveld refinement package. The XRD and SEM analyses demonstrate that the size and morphology of the products are insensitive to the variation of experimental conditions. The photoluminescence properties of the Eu3+, Ce3+, and Tb3+ single-doped as well as Ce3+-Tb3+ codoped BaYF5 nanocrystals were characterized. The results reveal that the existence of the Ce3+ ions can dramatically enhance the emission intensity of the Tb3+ ions, due to an efficient energy transfer from the Ce3+ to Tb3+ ions in the BaYF5:Ce3+,Tb3+ nanocrystals. The critical energy transfer distance between the Ce3+ and Tb3+ ions was calculated by methods of concentration quenching a...

The multi-morphological coordination polymer La(1,3,5-BTC)(H2O)6 has been prepared through simple and mild one-step approaches at room temperature on a large scale (1,3,5-BTC = 1,3,5-benzenetricarboxylate). The delicate sheaflike, broccolilike, urchinlike, and fanlike hierarchical architectures made of uniform nanorods were obtained through splitting crystal growth. More interestingly, these three dimensional architectures can exhibit tunable white-light emission by codoping Tb3+ and Eu3+.

Large-scale GdVO4:Eu3+ nanowires with diameters of about 15 nm and lengths of several micrometers were achieved by a facile hydrothermal method in the presence of disodium ethylenediamine tetraacetate (Na2H2L). The influences of several parameters, such as pH value, reaction temperature, and molar ratio of Na2H2L to Gd3+ on the final products were investigated. The formation mechanism of the as-obtained GdVO4:Eu3+ nanowires is proposed on the basis of time-dependent experiments. It is found that the organic additive Na2H2L, which acts as a shape modifier, has a dynamic effect by adjusting the growth rates of different facets, resulting in the formation of the GdVO4:Eu3+ nanowires. The luminescent spectrum of GdVO4:Eu3+ nanowires shows the strong characteristic dominant emission of the Eu3+ ions at 614 nm.

Hierarchically nanostructured coordination polymer Ce(1,3,5-BTC)(H2O)6 architectures with tunable morphologies have been successfully prepared on a large scale via a simple and rapid solution phase method at room temperature. The as-synthesized products are characterized by X-ray diffraction, thermogravimetric analysis, energy dispersive X-ray (EDX) analysis, scanning electron microscopy, and transmission electron microscopy, respectively. A possible splitting formation mechanism for the interesting architectures has been proposed to interpret the growth process. By rationally adjusting the synthetic parameters such as concentration, reaction temperature, surfactant, solvent, static, and ultrasonic treatment, Ce(1,3,5-BTC)(H2O)6 with straw-sheaflike, flowerlike, wheatearlike, strawlike, bundlelike, and urchinlike architectures, and nanorods can be selectively obtained. This facile, rapid, mild, cost-effective, reproducible, and environment-friendly growth strategy has considerable potential, and could rea...

Sheaflike terbium phosphate hydrate hierarchical architectures composed of filamentary nanorods have been fabricated by a hydrothermal method. The X-ray diffraction patterns and thermogravimetric/d...

Uniform NaLuF(4) nanowires and LuBO(3) microdisks have been successfully prepared by a designed chemical conversion method. The lutetium precursor nanowires were first prepared through a simple hydrothermal process. Subsequently, uniform NaLuF(4) nanowires and LuBO(3) microdisks were synthesized at the expense of the precursor by a hydrothermal conversion process. The whole process was carried out in aqueous condition without any organic solvents, surfactant, or catalyst. The conversion processes from precursor to the final products have been investigated in detail. The as-obtained Eu(3+) and Tb(3+)-doped LuBO(3) microdisks and NaLuF(4) nanowires show strong characteristic red and green emissions under ultraviolet excitation or low-voltage electron beam excitation. Moreover, the luminescence colors of the Eu(3+) and Tb(3+) codoped LuBO(3) samples can be tuned from red, orange, yellow, and green-yellow to green by simply adjusting the relative doping concentrations of the activator ions under a single wavelength excitation, which might find potential applications in the fields such as light display systems and optoelectronic devices.

The nonstoichimetric Ba0.92Y2.15F8.29 submicrospheres that piled up by nanoparticles have been prepared via a solution-based method in a hydrothermal environment. The size distribution of the submicrospheres could be tuned by varying the amount of BaCl2. The fluoride source NaBF4 plays an important role in the formation of the submicrospheres. The chelator ethylenediaminetetraacetic acid regulates the growth of the primary nanoparticles as well as the aggregated submicrospheres. The photoluminescence properties of different concentrations of Eu3+-doped Ba0.92Y2.15F8.29 were investigated and the results revealed that the 8% concentration of Eu3+ ions is the optimum doping concentration and the Y3+ ions occupy the site of inversion symmetry.

Three series of R2MoO6:Eu (R = La, Gd, and Y) phosphor powders were synthesized by using the sol−gel method, and then the powder was annealed at a gradually decreased temperature from 1200 to 700 °...

Novel one-dimensional europium benzene-1,3,5-tricarboxylate compressed nanorods have been synthesized on a large scale through direct precipitation in solution phase under moderate conditions without the assistance of any surfactant, catalyst, or template. The obtained nanorods have widths of about 50−100 nm, thicknesses of 10−20 nm, and lengths ranging from a few hundred nanometers to several micrometers. X-ray powder diffraction, elemental analysis, Fourier transform infrared studies, and thermogravimetric and differential thermal analysis show that the nanorods have the structural formula of Eu(1,3,5-BTC)·6H2O. Upon UV excitation, these nanorods exhibit a highly efficient luminescence, which comes from the Eu3+ ions. Moreover, Eu2O3 nanorods could also be obtained via a thermal decomposition method using the corresponding complex as a precursor. This synthetic route is promising for the preparation of other one-dimensional crystalline nanomaterials because of its simplicity and the low cost of the star...

Uniform MF/YVO4:Ln(3+) (Ln = Eu, Dy, and Sm) composite microspheres have been prepared via a simple and economical wet-chemical route at ambient pressure and low temperature. Monodisperse micrometer-sized melamine formaldehyde (MF) colloidal particles were first fabricated by a condensation process of melamine with formaldehyde. Subsequently, well-dispersed YVO4 nanoparticles were successfully grown onto the MF microspheres to form core-shell structured composite particles in aqueous Solution. The as-obtained composite microspheres with perfect spherical shape are uniform in size and distribution, and the thickness and roughness of the YVO4 shells on MF cores could be tuned by varying the reaction temperature. The MF/YVO4:Ln(3+) composite phosphors show strong light emissions with different colors coming from different activator ions under ultraviolet excitation, which might find potential applications in fields such as light phosphor powders and advanced flat panel displays.

Uniform Gd(OH)(3) nanotubes have been prepared via a simple wet-chemical route at ambient pressure and low temperature, without any catalysts, templates, or substrates, in which Gd(NO3)(3) was used as the gallium source and ammonia as the alkali. SEM and TEM images indicate that the as-obtained Gd(OH)3 entirely consists of uniform nanotubes in high yield with diameters of about 40 nm and lengths of 200-300 nm. The temperature-dependent morphological evolution and the formation mechanism of the Gd(OH)(3) nanotubes were investigated in detail. Furthermore, the Gd2O3 and Eu3+-doped Gd2O3 nanotubes, which inherit their parents' morphology, were obtained during a direct annealing process in air. The corresponding Gd2O3:Eu3+ nanotubes exhibit the strong red emission corresponding to the D-5(0)-F-7(2), transition of the Eu3+ ions under UV light or low-voltage electron beam excitation, which might find potential applications in the fields such as light-emitting phosphors, advanced flat panel displays, or biological labeling.

Uniform Lu2O3:Eu3+ nanorods and nanowires have been successfully prepared through a simple solution-based hydrothermal process followed by a subsequent calcination process without using any surfactant, catalyst, or template. On the basis of X-ray diffraction, thermogravimetric analysis and differential scanning calorimetry, and Fourier transform infrared spectroscopy results, it can be assumed that the as-obtained precursors have the structure formula of Lu4O(OH)9(NO3), which is a new phase and has not been reported. The morphology of the precursors could be modulated from nanorods to nanowires with the increase of pH value using ammonia solution. The as-formed precursors could transform to cubic Lu2O3:Eu3+ with the same morphology and a slight shrinkage in size after an annealing process. Both the Lu2O3:Eu3+ nanorods and nanowires exhibit the strong red emission corresponding to the 5D0 −7F2 transition of the Eu3+ ions under UV light excitation or low-voltage electron beam excitation.