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The room-temperature reactions between N-benzoyl- l -glutamic acid (H2bzgluO), zinc salts and ex-bidentate N-donor ligands in acidic CH3OH/H2O solutions yielded two new coordination polymers, [Zn(bzgluO)(bpp)]n·1.75nH2O (bpp = 1,3-bis(4-pyridyl)propane) (1) and [Zn(bzgluO)(4,4-bipy)0.5]n (4,4-bipy = 4,4-bipyridine) (2). The two complexes have been characterized using single-crystal X-ray diffraction, infrared spectra, elemental analysis, thermogravimetric analysis and powder X-ray diffraction analysis. The X-ray structural determination indicates that complex 1 crystallizes in the monoclinic space group C2 and displays a 2-D wave-like sheet structure, while complex 2 crystallizes in the tetragonal space group P4(3)2(1)2 and presents a 3-D network structure. The structural difference indicates that the effect of N-donor ancillary ligand is critical in construction of polymeric arrangement. Moreover, the solid-state photoluminescent properties of the two coordination polymers change also according to the N-donor ancillary ligand introduced.

(PO4)3- -doped red phosphors, Na5Eu(MoO4)4-x(PO4)x (x ≤ 0.10), were prepared by the conventional solid-state reaction method, and their luminescent properties were studied. Under the excitation of near-UV 395 nm, the phosphors show intense red emission. In particular, the relative emission intensity of Na5Eu(MoO4)3.96(PO4)0.04 sample reaches about 5.0 times in comparison with that of the commercial red phosphor Y2O2S:Eu3+. The phosphor could be suitable for the application of white light-emitting diodes.

The lithium ions doped red-emitting phosphors of (Ca,Eu)WO4 and (Ca,Eu)MoO4 were synthesized by solid-state reaction method, and their luminescent properties were investigated. The XRD patterns show that the phosphors are isostructural and share a tetragonal scheelite structure, even some lithium ions are doped. The excitation spectra consist of broad charge transfer bands in the short-wave UV region of W6+→O2- and Eu3+→O2- with three sharp lines around 395, 465 and 535 nm of the Eu3+ 4f excitation transitions. The characteristic emissions of WO4 2- and MoO4 2- are quenched absolutely and red light emission of Eu3+ exhibits predominate peak around 615 nm due to the electric dipole energy transition of 5D0→7F2. Excited with 395 nm, the evident enhanced emission of the phosphors were observed when Li+ doped in the host, which implies that the addition of some Li+ is beneficial for the energy transfer from WO4 2- or MoO4 2- to Eu3+.

Nanocrystalline infrared-to-visible upconverting phosphors Gd2O3:Yb,Er with narrow size distribution were prepared by using a microemulsion system (MES) of stability, which includes phases of Triton X-100 (surfactant phase (s)), n-hexanol (assistant surfactant phase (As)), cyclohexane (oil phase (O)) and solution (water phase (W)). From the microemulsion system we could get appearance-controllable nanocrystalline by adjusting the ratio of oil and surfactant. The X-ray diffraction results showed that the powders were cubic phase of Gd2O3 after being calcined in the air at 1273 K. The scanning electronic microscopy revealed that the particles were spherical. Red and green upconversion luminescences were obtained by 980 nm infrared excitation. We also investigated contributions of different ratio of surfactant to the appearance.

A series of powders of (Ba1-xLa2x/3)(Ti1-xNb4x/5)O3 (0.05≤x≤0.3) have been synthesized by solid-state reaction route, and the effects of the dopants on the microstructure of BaTiO3 were investigated by XRD, SEM, HTEM and EDS in the BaTiO3-La2O3-Nb2O5 ternary system. It was found that the secondary titanium-rich phase occurred for x ≤ 0.1, while Ba3La3Ti5Nb5O30 yields as secondary phase for x ≥ 0.2. In the whole range of 0.05 ≤ x ≤ 0.3, the crystal structure of BaTiO3 solid solutions is cubic system. There are two substitution modes in the system: the substitution mode of La ions dissolved into Ba sites is significant for x ≤ 0.2, but the substitution mode of Nb ions dissolved into Ti sites is significant for x>0.2. TEM observation and EDS analysis revealed that the concentration gradient of Nb existed and La almost distributed homogeneously in a grain. Thus, the dielectric materials composed of La-Nb-codoped BT are not fitted to form the core-shell structure for the higher dopants.

Infrared-to-visible upconversion phosphors Y2O3: Yb, Er and Gd2O3:Yb, Er with narrow size distribution were synthesized by using a stable microemulsion system, which included triton X-100, n-hexanol, cyclohexane and water. Appearance-controllable nanocrystals were achieved by adjusting the ratios of assistant surfactant and surfactant. The X-ray diffraction patterns of the samples showed that the powders were cubic phases of Y2O3 and Gd2O3, respectively. After calcination with different temperature settings in air atmosphere, the particles were spherical through the observation by scanning electronic microscopy. Red and green upconversion luminescence was obtained under 980 nm infrared excitation. Several contributions to the intensity of upconversion emission were also investigated. These upconversion phosphors may be used as fluorescent labels for the sensitive detection of biomolecule, immunoassay or DNA assays.

The precursor powder of Sr2CeO4 was prepared from a nitrate starting solution by a combustion route with urea as a fuel. Sintering the precursor powder at different temperatures for 6h, a blue-white emission phosphor was synthesized. The microstructure and photoluminescence studies of Sr2CeO4 compound are reported. The particle sizes of the powder phosphor are around 0.5-2 µm when heat treated between 9500C to 11500C and the emission spectrum exhibits a broad band maximum at about 470 nm. The chemical purity and photoluminescence intensity of Sr2CeO4 powder phosphor strongly depend on the post-heat-treated temperature.

The luminescent properties of terbium complex (terbium citrate) by binding to silver nanopartilces in the solution have been reported in this paper. The enhanced luminescence of the complex containing silver nanoparticies was observed at a limited particle concentration region. The nanoparticle concentration dependence of the luminescent intensity was regarded as the result of a delicate balance between an enhancing and a quenching effect of the silver nanoparticles. Furthermore, silver nanoparticles also affected the asymmetric ratio (AS) value of terbium luminescence. We discuss the luminescent properties of the terbium complex in terms of the local electromagnectic field, refractive index, and the ligand field around terbium ion.

Carbonate precursor of Eu3+ doped Sr2CeO4 is obtained from a mixed solution of strontium, cerium and europium nitrate using ammonium carbonate as precipitant. Calcining the carbonate precursor at different temperatures, the Eu3+ doped Sr2CeO4 phosphor is synthesized. The phase purity of the material is closely related with the calcination temperature, and the phosphor with high purity can be achieved after the precursor annealed at 1200°C. The photoluminescence performance for Eu3+ doped Sr2CeO4 depends on the concentration of Eu3+. The excitation and emission reveal efficient energy transfer from Ce4+ to Eu3+, making the emission light from blue-white to red-white, further to red as the Eu3+ concentration gradually changes from low concentration (1 mol%) to high concentration (10 mol%).

We have improved an electrochemical process in which the alternate current (AC) electrodeposition combined with the etching of substrate to prepare transparent metallic nanoparticles and anodic alumina oxide (AAO) composite films. The new process greatly simplifies the direct current (DC) electrodeposition process to get transparent composite films. Moreover, the electrocrystallization mechanism has been analyzed. The Ag, Cu and Ag-Cu co-deposited nanoparticles/AAO films have distinct absorption peaks, which can be ascribed to the surface plasmon resonance (SPR) of these noble metal nanoparticles.

Sulfide nanowire arrays have been synthesized by DC electrodeposition from an electrolyte containing S in DMSO. The AAO membrane with the barrier layer has been directly used as template in electrodeposition. The as-synthesized products are characterized by SEM, TEM and resonance Raman spectroscopy. CdS and ZnS nanowires have been obtained, respectively.

Surfactant-zirconium phosphate composites were prepared by surfactant cetyltrimethylammonium bromide intercalating to α-zirconium phosphate. The interlayer spacing of the lamellar structure was greatly expanded to 39.6 Å, as compared to 7.6 Å of α-zirconium phosphate. The molar ratio of surfactant to α-zirconium phosphate in the composites was found to be 1/1.46. The expanded interlayer separation is beneficial for complicated guest molecules intercalating to the galleries of the composites.

This paper presented the absorption and fluorescence spectra as well as luminescence lifetime of tris(2,2'-bipyridine)ruthenium(II) (abbreviated as Ru(bpy) 2+ 3 ) intercalated to modified α-zirconium phosphate in aqueous media. The results showed extensive red shifts of the absorption band of the metal complex (from 454 to 482 nm) and blue shifts of the emission maximum (from 610 to 582 nm) as compared to that of free chromophore. On the other hand, the luminescence intensities and the excited-state lifetimes of the metal complex were dramatically increased. X-ray diffraction (XRD) patterns of the powder samples indicated that intercalation of Ru(bpy) 2+ 3 into modified α-zirconium phosphate reduced somewhat the interlayer separation from 18.6 to 17.1 A. In addition, spectroscopic measurements for Ru(bpy) 2+ 3 with modified α-zirconium phosphate in ethanol media were also proceeded. No significant difference was observed, which implied that Ru(bpy) 2+ 3 could not enter into modified α-zirconium phosphate in ethanol media.

In the present paper two series of mixed rare earth complexes Tb(1-x)LnxBTC x nH2O (Ln = Y, Gd, x = 0, 0.1, 0.3, 0.5, 0.7, 0.9) were synthesized by hydrothermal method. The contents of rare earth were measured by using EDTA titration method; the element analyses of C and H were performed by using Vario EL III elemental analyzer, and the IR spectra were recorded by FTIR-8900 infrared spectroscopy with KBr pellet. Then the molecular formula of the complexes were determined to be Tb(1-x)LnxBTC x 0.5H2O (Ln = Y, Gd). The fluorescence spectrum of all the complexes were recorded by using a Hitachi F-4500 fluorescence spectrophotometer at room temperature. The results indicated that all the complexes emitted characteristic fluorescence of Tb3+, and the fluorescence intensities of the complexes were obviously enhanced with doping rare earth ion of Y3+ or Gd3+. It was showed that Tb3+ was sensitized by doping rare earth ions. This may be because there was intra molecular energy transfer in the complexes. Being doped with the rare earth ion the emission peak positions did not change. Among the four emission peaks, 5D4 --7F5 (544 nm) was the strongest one, and it was found when the proportion is Y3+ : Tb3+ = 0.5 : 0.5 or Gd3+ : Tb3+ = 0.3 : 0.7, the fluorescence intensity of Tb(1-x)YxBTC x 0.5H2O or Tb(1-x)GdxBTC x 0.5H2O was the greatest, meanwhile the sensitization degree was bigger with doping Gd3+ than doping Y3+ at 544 nm.

In the present paper, the authors studied the effects of KCl on the fluorescence of [Ru(bpy)3]2+ solution containing silver nanoparticles by UV-Vis absorption spectra and fluorescence spectra. The results indicated that the stronger action between KCl and silver nanoparticles led to the vanishing of chain-like net structure formed between [Ru(bpy)3]2+ and silver nanoparticles and the formation of large particles and aggregates in the solution. Meanwhile, a new band at longer wavelength region appeared and the peak at long wavelength was red-shifted and broadened with the increase of KCl. With the increase in KCl content, the fluorescence decreases first and then increases till a constant value. The authors discussed the mechanism of the effects KCl on the fluorescence of [Ru(bpy)3]2+ solution containing silver nanoparticles in terms of interaction and energy transfer.

The precursor powders of Sn3+ doped Sr2CeO4 were obtained by the application of (NH4)2C2O4 as a precipitant. After calcinations, the precursor powders became a white emitting fluorescent material. The XRD and emission spectra manifest that the optimum temperature and Sm3+ concentration for synthesizing Sr2CeO4:Sm are 1 050 degrees C and 1 mol%, respectively. The better the phosphor powders crystallize, the higher their emission intensities are. The excitation spectrum implies that the transition emissions of Sm3+ at 608 and 654 nm originate from the Ce4+ -O(2-) charge transfer (MLCT) resulting from the interaction of Ce4+ and the neighboring O2-. Therefore, it can be concluded that the host Sr2 CeO4 acts as a sensitizer, which transfers the energy to Sm3+. The emission intensity of the phosphor synthesized through co-precipitation is much higher than that of phosphor prepared using conventional solid state reactions.

Transparent copper nanorod/nanowire arrays and anodic alumina oxide composite films have been prepared by alternating current electrodeposition, and their linear optical properties have been systematically characterized by absorption spectra. In the experimental spectra, there exist transverse and longitudinal resonance peaks, which are caused by the surface-plasmon resonance along the diameter and the length of the copper nanorods, respectively. The transverse resonance peak is affected by the diameter and aspect ratio of the nanorod. The longitudinal resonance peak appears at longer wavelength when a polarized light illuminates the film with an angle of incidence of about 70 degrees , where the angle is defined with respect to the surface normal. Moreover, the longitudinal resonance mode is sensitive to the polarization direction when compared with the transverse resonance mode.