bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of Highly Crystallized Yttrium Oxysulfide Suspension via a Novel Colloidal Processing
Authors: Wang Hong , Jiang Tao , Xing Ming-Ming , Fu Yao , Peng Yong , Luo Xi-Xian
Published: April 2016

High-crystallized Y2O2S suspension was synthesized by a novel two-step method of high temperature solid-state reaction and subsequent colloidal processing. The synthesis method proposed in this study retains all advantages of the high temperature solid-state reaction
method. The obtained data agrees with that of the PDF card, which indicates the product is pure Y2O2S crystals. The results show that the prepared Y2O2S particles are highly crystallized without any significant defects. The fine smooth particles
were almost regular, exhibiting an approximately subspherical shape. Quantitative image analysis of particles suggests a mean particle size of 120±34 nm. That is to say, the yttrium oxysulfide colloid prepared by this method have a very narrow size distribution. The obtained ethanol
suspension shows Tyndall effect when irradiated with laser of wavelength 532 nm. In addition, the particles exhibit excellent dispersibility in ethanol solution. This is rarely observed for the covalent compounds, which generally present poor dispersibility in solution. As is known to all,
the state of the dispersion depends on the acid leaching process. The acid leaching process facilitates the adsorption of ethanol molecules on the surface of the particles. The electrostatic repulsive force among colloidal particles will improve their rheological properties and dispersibility
in solution. In this study, the particles can be dispersed well in ethanol after acid leaching. The method proposed in this study can be extended for the preparation of mono-dispersed oxysulfide nanophosphors and may provide an efficient way for the preparation of stable covalent compound
dispersions.
Laser Spectroscopy of GdPO4 · nH2O:Eu Nanomaterials
Authors: Lu Shaozhe , Zhang Jiahua , Zhang Jishen , Shulin E , Zhao Haifeng , Luo Yongshi
Published: April 2016

One-dimensional GdPO4 · nH2O:Eu nanowires and nanorods of different sizes and the same structure were synthesized by hydrothermal method. Nanowire and nanorods had width and length of about 10 nm/50 nm and 80 nm/1 μm, respectively. Adjusting
reaction system PH value by adding alkali metal NaOH, the size and shape of the product can be tuned. The high resolution spectra, excitation spectra, and laser selective excitation spectra at low temperature were determined. Nanorod compared with nanowire, photoluminescence was enhanced,
and the excitation spectrum and laser selective excitation spectra were broadened. These results suggest that Eu3+ in GdPO4 · nH2O nanorod and nanowire were located in different local environments.
A Green Route to Hexagonal and Monoclinic BiPO4:Ln3+ (Ln = Sm, Eu, Tb, Dy) Nanocrystallites for Tailoring Luminescent Performance
Authors: Yang Errui , Li Guangshe , Zheng Yunlong , Li Liping
Published: April 2016

Selective synthesis of specific phased nanomaterials via a green route is a promising yet challenging task. In the present work, the hexagonal and monoclinic phases of BiPO4:Ln3+ (Ln = Sm, Eu, Tb, Dy) were prepared via room temperature co-precipitation method.
For adjusting the phase of the products, the prepared mediums selected were the most common solvents, i.e., water and ethanol. It was very important that the prepared mediums could be easily recycled and reused by evaporating the filtrate. The formation mechanisms of hexagonal in water and
monoclinic in ethanol were investigated. Interestingly, the growth behaviors of these phases were quite distinct and thus gave rise to distinct morphology and particle size. The hexagonal phase possesses a rod-like morphology with diameters of 50–160 nm and lengths of 65–400 nm
while the monoclinic phase consists of almost entirely irregular nanoparticles. Also, it was found that the bending and stretching vibrations of O–H and PO4 tetrahedra were quite different for the products prepared in water and ethanol. Moreover, it was found that the luminescence
properties, including emission intensity, lifetime, quantum efficiency, and color, could be readily tailored through controlling the phase structures and microstructures. The results showed that the monoclinic phase exhibited superior luminescent performance to the hexagonal phase. The methodologies
reported in this work were fundamentally important, which could be easily extended to large-scale synthesis of other phased nanomaterials for potential applications as electroluminescent devices, optical integrated circuits, or biomarkers.
Effect of Gallium and Indium Co-Substituting on Upconversion Properties of Er/Yb:Yttrium Aluminum Garnet Powders Prepared by the Co-Precipitation Method
Authors: Zhang Wei , Liang Yun-Ling , Hu Zheng-Fa , Feng Zu-Yong , Lun Ma , Xiu-Ping Zhang , Sheng Xia , Liu Qian , Luo Jie
Published: April 2016

Gallium and Indium co-substituted Yb, Er:YAG was fabricated through the chemical co-precipitation method. The formation process and structure of the Ga3+ and In3+ substituted phosphor powders were characterized by the X-ray diffraction, thermo-gravimetry analyzer,
infrared spectra, and X-ray photoelectron spectroscopy, and the effects of Ga3+ and In3+ concentration on the luminescence properties were investigated by spectrum. The results showed that the blue shift occurred after the substitution of Ga3+ and In3+
for Al3+ in matrix, and the intensity of emission spectrum was affected by the concentration of Ga3+ and In3+.
Research on the Luminescence and Temperature Quenching Properties of BaSi2O2N2:Eu2+ Phosphor
Authors: Wang Lingli , Ni Haiyong , Zhang Qiuhong , Xiao Fangming
Published: April 2016

The BaSi2O2N2:Eu2+ phosphor is synthesized by solid state reaction. The luminescent properties and temperature quenching performance of BaSi2O2N2:Eu2+ phosphor are measured. It has been demonstrated
that the Eu2+ doped BaSi2O2N2 phosphor shows efficient green emission with peak at around 492 nm. With the incorporation of La3+ and Y3+, the quantum efficiency of BaSi2O2N2:Eu2+ and
the temperature quenching performance of BaSi2O2N2:Eu2+ is changed, which is explained from the electronic structure view.
Facile Synthesis and Growth Mechanism of SiO2 Nanotubes with ZnS Nanowires as Intermediates
Authors: Chuo Hui Xin , Wu Li Li
Published: April 2016

SiO2 nanotubes with good chemical purity and well defined morphology were synthesized successfully in a one-step gas phase condensation process using gold catalyst. The as-synthesized products were characterized by transmission electron microscopy and nanoprobe X-ray energy
dispersive. In the observations, a growth mechanism of the nanotubes is suggested. The new synthetic route to prepare SiO2 nanotubes is favorable to satisfy the special needs in commercial and industrial application and can be easily applied to other semiconductor materials.
Effect of the Dosage of Tourmaline on Far Infrared Emission Properties of Tourmaline/Glass Composite Materials
Authors: Zhang Hongchen , Meng Junping , Liang Jinsheng , Liu Jie , Zeng Zhaoyang
Published: April 2016

Tourmaline/glass composite materials were prepared by sintering at 600 °C using micron-size tourmaline mineral and glass powders as raw materials. The glass has lower melting point than the transition temperature of tourmaline. The Fourier transform infrared spectroscopy showed
that the far infrared emissivity of composite was significantly higher than that of either tourmaline or glass powders. A highest far infrared emissivity of 0.925 was obtained when the dosage of tourmaline was 10 wt%. The effects of the amount of tourmaline on the far infrared emission properties
of composite was also systematically studied by field emission scanning electron microscope and X-ray diffraction. The tourmaline phase was observed in the composite, showing a particle size of about 70 nm. This meant that the tourmaline particles showed nanocrystallization. They distributed
homogenous in the glass matrix when the dosage of tourmaline was not more than 20 wt%. Two reasons were attributed to the improved far infrared emission properties of composite: the particle size of tourmaline-doped was nanocrystallized and the oxidation of Fe2+ (0.076 nm in radius)
to Fe3+ (0.064 nm in radius) took place inside the tourmaline-doped. This resulted in the shrinkage of unit cell of the tourmaline in the composite.
Influence of Water Activated by Far Infrared Porous Ceramics on Nitrogen Absorption in the Pig Feed
Authors: Meng Junping , Liu Jie , Liang Jinsheng , Zhang Hongchen , Ding Yan
Published: April 2016

Under modern and intensive feeding livestock and poultry density has increased, and brought a deterioration of the farm environment. The livestock and their excrement generate harmful gases such as ammonia, etc. which restricted the sustainable development and improvement of production
efficiency of animal husbandry. In this paper, a new kind of far infrared porous ceramics was prepared to activate the animal drinking water. The activated water and common water were then supplied to pigs, and the fresh pig feces of experimental group and control group were collected on a
regular basis. The residual protein content in feces was tested by Kjeldahl nitrogen method to study the influence law of the porous ceramics on absorbing nitrogen element in animal feces. The results showed that compared with the control group, the protein content in the experimental group
decreased on average by 39.2%. The activated drinking water was conducive to the absorption of nitrogen in pig feed. The clusters of water molecules became smaller under the action of the porous ceramics. Hence, they were easy to pass through the water protein channel on the cell membrane
for speeding up the metabolism.
Charge and Energy Transfer Between CdSe Quantum Dots and Polyaniline
Authors: Xu Liang , Huang Xingbin , Dai Wenjiang , Sun Punan , Chen Xuanlin , An Limin
Published: April 2016

CdSe quantum dots (QDs) and polyaniline (PAni) were mixed to prepare CdSe QDs/PAni complex. PAni can quench the fluorescence of CdSe QDs. Fluorescence intensity of CdSe QDs/PAni complex is related to the size of CdSe QDs and the concentration of PAni. UV-Vis absorption spectra, fluorescence
spectra, time-resolved fluorescence spectroscopy were used to analys the quenching phenomenon. The mechanism of fluorescence quenching is dependent on two factors: on one hand, the Förster resonance energy transfer from CdSe to PAni; on the other hand, PAni can intercept the charge relaxation
process of CdSe and lead to the interruption of radiative recombination.
Facile Synthesis of r-GO @Pd/TiO2 Nanocomposites and Its Photocatalytic Activity Under Visible Light
Authors: Dao Anh Quang , Zheng Bijuan , Liu Hongwei , Dong Shuang , Thi Thanh Tuyen Le , Fu Chaoyang , Liu Hongfang
Published: April 2016

Reduced Graphene Oxide Wrapped Pd/TiO2 (r-GO@Pd/TiO2) which exhibited high photocatalytic activity under visible light was synthesized from commercial chemicals. The classic sol–gel method and the Ar gas bubbling composition was used in the preparation of
the catalyst. Furthermore, the best Pd-doping concentration in crystals, the wrapping concentration of r-GO over nanoparticles, and the optimal calcination temperature were investigated to enhance the photocatalytic activity of the hybrid catalyst. The experimental results showed that the
catalytic efficiency of r-GO@Pd/TiO2 reached maximum value at the optimum synthesis conditions: 0.7 wt% Pd-doped TiO2 by sol–gel process, calcination temperature of 550 °C, 1 mg of GO for 100 gram wrapped Pd/TiO2. X-ray Diffraction (XRD), Scanning
Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM) techniques were conducted to determine the nanostructure of the catalysts. The average crystallite size of nanoparticles was 14 nm with perfect dispersion of Pd dots and wraps of r-GO membrane. Methyl Blue was used as an
organic dye model to test the ability in wastewater treatment of the catalysts. A comparison between different catalysts’ characteristics was also studied. The r-GO@Pd/TiO2 showed a higher photocatalytic activity compared to Pd/TiO2 and commercial P25. Additionally,
the complete dye reduction under visible light excitation indicated that wrapping r-GO round Pd/TiO2 improved the photocatalytic activity of catalysts. The determination of the stability of r-GO@Pd/TiO2 showed that its photocatalysis was persistent over several times
of recycling examination. Therefore, r-GO@Pd/TiO2 in wastewater treatment.
Synthesis and Upconversion Luminescence of Water-Soluble of GdF3:Yb3+/Er3+ Nanoparticles
Authors: De Gejihu , Asina B , Ma Wujiseleng
Published: April 2016

Water-soluble Yb3+/Er3+ doped GdF3 nanocrystals were prepared using a thermal decomposition synthesis route. The crystal structure, morphology and up-conversion spectra of the samples were characterized using X-ray powder diffractometry, transmission
electron microscopy and a fluores- cence spectrophotometer with single-wavelength diode laser of 980 nm. In Yb3+- and Er3+-codoped GdF3 nanocrystals, the relative intensity of green emission became stronger as the sample changed from water-soluble nanoparticles
to hexane-dispersed nanoparticles. The synthesis of such monidisperse, water-soluble, lanthanide-doped upconvertion particles will open new opportunities in targeting and drug delivery applications.
Structure and Optimum Luminescence for Nearly Block-Like LaOCl:Eu3+ Nanoparticles
Authors: Lv Li , Zhai Hao , Liu Xiaoqing , Su Yiguo , Wang Xiaojing
Published: April 2016

In this work, we report a simple method for the synthesis of block-like Eu3+ doping LaOCl nanophosphors with different doping content. It was found that the average grain diameter of Eu3+ doping LaOCl samples decreased with increasing Eu3+ doping concentration.
The lattice volume shrinked due to different response for different axial under high pressure that led to lower lattice symmetry of LaOCl:Eu3+. The emission of LaOCl:Eu3+ increased with the increasing Eu3+ concentration due to the lower local symmetry, which
also led to a gradual reduction in lifetime.
Synthesis and Characterization of α-ZrP@CHI Drug Deliver System
Authors: Yu Shiyong , Gao Xuechuan , Zhang Renfei , Li Zhao , Tan Zhibing , Su Haiquan
Published: April 2016

This paper described the controlled synthesis and release properties of a new kind of multifunctional drug-release system which was prepared by encapsulation of zirconium bis-(monohydrogen orthophosphate) monohydrate (α-ZrP) with chitosan (CHI). As obtained the α-ZrP@CHI
nanocomposites were found to possess the structural features of both α-ZrP and CHI. The release properties of the α-ZrP@CHI nanocomposites were evaluated using Gentamicin sulfate as the model drug. And α-ZrP@CHI composites showed a prolonged drug release
time compared with α-ZrP, which can be attributed to the unique lamellar structure and the encapsulation with CHI. The controlled synthesis of α-ZrP@CHI nanocomposite thus provided a new opportunity for future development of delivery vehicles.
Ce3+ and Ln3+ (Ln = Dy, Eu, Sm, Tb) Codoped SrF2 Nanoparticles: Synthesis and Multicolor Light Emission
Authors: Su Yiguo , Liu Mengqing , Han Dan , Li Lv , Wang Tingting , Wang Xiaojing
Published: April 2016

For optically active Ln3+ ions, fluoride is a very good luminescent substrate that has been used in the field of lasers, solid-phase optical transmitters, optical communications, up/down conversion. This work reports a systematic study on bridging between structure and tunable
luminescence for SrF2:Ce3+/Ln3+ (Ln = Dy, Eu, Sm, Tb) nanoparticles. Regardless of the dopant level, all nanocrystals crystallized in a single cubic phase with the diameter of ∼20–30 nm. It was found that SrF2:Ce3+ exhibited
intense ultraviolet emission under 288 nm excitation which can be attributed to the typical 4f-5d transition of Ce3+ ions. After the incorporation of Ln3+ ions, multicolor emission can be achieved when excited by the 4f-5d transition of Ce3+.
This result gave an evidence that the excitation energy of Ce3+ canbe transferred toLn3+ leading to multicolor emission. The findings reported in this work may provide useful information in designing novel luminescent materials for tailored performances.
Synthesis and Characterization of SiO2@Y2MoO6:Eu3+ Core–Shell Structured Spherical Phosphors by Sol–Gel Process
Authors: Li G. Z , Liu F. H , Chu Z. S , Wu D. M , Yang L. B , Li J. L , Wang M. N , Wang Z. L
Published: April 2016

SiO2@Y2MoO6:Eu3+ core–shell phosphors were prepared by the sol–gel process. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray
spectra (EDS), transmission electron microscopy (TEM), photoluminescence (PL) spectra as well as kinetic decays were used to characterize the resulting SiO2@Y2MoO6:Eu3+ core–shell phosphors. The XRD results demonstrated that the Y2MoO6:Eu3+
layers on the SiO2 spheres crystallized after being annealed at 700 °C and the crystallinity increased with raising the annealing temperature. The obtained core–shell phosphors have spherical shape with narrow size distribution (average size ca. 640 nm), non-agglomeration,
and smooth surface. The thickness of the Y2MoO6:Eu3+ shells on the SiO2 cores could be easily tailored by varying the number of deposition cycles (70 nm for four deposition cycles). The Eu3+ shows a strong PL emission (dominated by 5D0–7F2
red emission at 614 nm) under the excitation of 347 nm UV light. The PL intensity of Eu3+ increases with increasing the annealing temperature and the number of coating cycles.
Uniform Cerium-Based Coordination Polymer Microspheres: Preparation and Upconversion Emission
Authors: Nie Zhi-Wen , Zeng Cheng-Hui , Xie Gang , Zhong Sheng-Liang
Published: April 2016

Homogeneously doped Yb3+ and Er3+ cerium-based coordination polymer (CP) microspheres have been successfully synthesized on a large scale through a simple solvothermal route with 2, 5-pyridinedicarboxylic acid (2, 5-H2PDC) as the organic linker. CeO2:Yb3+,
Er3+ porous microspheres were obtained by annealing the corresponding CP microspheres at 600 °C for 4 h under atmospheric pressure. These as-prepared products were characterized by Powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy
(TEM), Fourier transform infrared spectroscopy (FTIR), energy-dispersion X-ray (EDX) spectroscopy, Thermogravimetric (TG) and derivative thermogravimetric (DTG) analysis. The room temperature upconversion luminescent spectra of the as-prepared microspheres were carried out by 980 nm NIR light
excitation. Interestingly, Yb3+ and Er3+ codoped CP microspheres give a single-band emission centered at 673 nm, while the CeO2:Yb3+, Er3+ microspheres give emission in green and red region, with red being the dominant emission. The emission
intensity of the CeO2:Yb3+, Er3+ microspheres were much stronger than that of the Yb3+ and Er3+ codoped CP microspheres.
Enhanced Red Upconversion Luminescence in Yb–Er Codoped NaYF4 Nanocrystals
Authors: Song Weiye , Bi Xueqing , Guo Xingyuan , Liu Shushen , Qin Weiping
Published: April 2016

In this work the effects of NaYF4:Yb, Er (NYE) structure on the enhanced red upconversion luminescence (UC) was investigated. -NYE nanocrystals (NCs) and -NYE NCs were fabricated by a high temperature decomposition reaction method. The prepared NCs were characterized by X-ray
diffraction (XRD), transmission electron microscopy (TEM), and photoluminescence (PL) spectroscopy. The results show that the red UC luminescence of -NYE NCs is significantly enhanced compared with that of -NYE. Furthermore, a possible energy transfer mechanism was proposed on the basis of
our experimental results.
The Effect of Phase Structures on the Enhanced Red Upconversion Luminescence in NaLuF4:Yb–Er Nanocrystals
Authors: Guo Xingyuan , Song Weiye , Bi Xueqing , Liu Shushen , Yin Shengyan , Qin Weiping
Published: April 2016

In this work, -NaLuF4:Yb, Er (NLF) nanocomposites (NCs) and -NLF NCs with diameter about ∼13 nm were fabricated by a high temperature decomposition reaction method. The effects of NLF structure on the enhanced red upconversion luminescence performance were investigated.
Under 980 nm excitation from a laser diode, the -NLF emitted dominant red UC emission. Furthermore, the possible energy transfer mechanism was proposed on the basis of our experimental results.
The Upconversion Luminescence Properties of Er3+/Tm3+, Yb3+-Codoped Cubic BaLiF3
Authors: Qiang Qinping , Guo Linna , Han Lili , Wang Yuhua
Published: April 2016

Cubic BaLiF3 samples were prepared using a facile surfactant-assisted hydrothermal-microemulsion method. The samples were characterized by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The upconversion luminescence (UCL) properties of the Er3+/Tm3+,
Yb3+-codoped BaLiF3 samples were measured under a 980 nm excitation wavelength. Moreover, the effects of varying the concentration of Li+ ions on the luminescence properties of Er3+, Yb3+ codoped BaLiF3 were also investigated.
The Tm3+, Yb3+ codoped BaLiF3 samples displayed multicolor emissions. This behavior can be explained by the pump power dependence of the upconversion emissions and the energy levels diagram.
Citrate-Complexation Synthesis and Photoluminescence Properties of Y6MoO12:Eu Nanocrystalline
Authors: Li Huaiyong , Pu Xipeng , Yao Shujuan , Wang Xiaoqing , Noh Hyeon Mi , Jeong Jung Hyun
Published: April 2016

Y6MoO12 doped with Eu3+ was synthesized using a citrate-complexation route, and was calcined at 800 °C and 1400 °C, respectively. The structure, morphology and photoluminescence (PL) properties of the samples, and their dependence on the crystallite
size were investigated. XRD patterns indicate that the Y6MoO12:Eu3+ powder was obtained at both calcination temperatures, and had a cubic structure. The results also suggest that Y6MoO12:Eu3+ calcined at 800 °C was in the
nanocrystalline phase, which was confirmed by the SEM microimage. The crystalline size was about 140 nm. Both phosphors could be excited via three channels: f–f excitation of Eu3+ by blue light, MoO groups excitation by near-UV light, and charge transfer state
excitation of Eu3+ by UV light. Both samples yielded red light emissions dominated by the 5D0–7F2 transition at 613 nm. The excitation efficient of the three channels depended on the calcination temperature. The energy transfer from
the MoO groups to the Eu3+ ions was more effective in the nanocrystalline phase. The temporal decay feature of the phosphor was also characterized.
Optical Temperature Sensor Based on Infrared Excited Green Upconversion Emission in Hexagonal Phase NaLuF4:Yb3+/Er3+ Nanorods
Authors: Li Dongyu , Tian Linlin , Huang Zhen , Shao Lexi , Quan Jun , Wang Yuxiao
Published: April 2016

Hexagonal phase NaLuF4:Yb3+/Er3+ nanorods were synthesized hydrothermally. An analysis of the intense green upconversion emissions at 525 nm and 550 nm in hexagonal phase NaLuF4:Yb3/+Er3+ nanorods under excitation
power density of 4.2 W/cm2 available from a diode laser emitting at 976 nm, have been undertaken. Fluorescence intensity ratio (FIR) variation of temperature-sensitive green upconversion emissions at 525 nm and 550 nm in this material was recorded in the physiological range from
295 to 343 K. The maximum sensitivity derived from the FIR technique of the green upconversion emissions is approximately 0.0044 K−1. Experimental results implied that hexagonal phase NaLuF4:Yb3/+Er3+ nanorods was a potential candidate
for optical temperature sensor.
Preparation and Properties of Ce3+:BaF2 Transparent Ceramics by Vacuum Sintering
Authors: Luo Junming , Ye Lifang , Xu Jilin
Published: April 2016

Ce0.001Ba0.999F2.001 powders were prepared by a chemical coprecipitation method using Ba(NO3)2, KF · 2H2O and Ce(NO3)3 · 6H2Oasraw materials. Ce0.001Ba0.999F2.001
transparent ceramics were prepared by vacuum sintering. The results show that the Ce0.001Ba0.999F2.001 powders were blocky, and both powdered and sintered transparent ceramics were composed of BaF2 phases without the secondary phase. The maximum
light transmittance of the Ce0.001Ba0.999F2.001 transparent ceramics reached 55%. The fracture morphology shows a cleavage fracture with a few micropores. The fluorescence spectra show that the Ce0.001Ba0.999F2.001 powders displayed
emissions at 410 nm, 480 nm and 620 nm under 275 nm excitation. The Ce0.1Ba0.9F2.1 transparent ceramics displayed emissions at 450 nm and 620 nm under 294 nm excitation.
Synthesis and Upconversion Luminescence of High-Quality Water-Soluble NaYF4:Yb3+, Er3+ Nanoclusters
Authors: Tang Jing , Wang Lianbo , Li Qiuping , Cui Yan , Wang Enyan , Jiang Lan , Jiang Tao
Published: April 2016

Hexagonal phase NaYF4:Yb3+, Er3+ nanoclusters were prepared using a facile solvothermal method. The structures and morphologies of the products were investigated using an X-ray powder diffractometer and a transmission electron microscope. Modified by
the capping agent of poly(acrylic acid), the as-prepared NaYF4 NCs show excellent water solubility. Under 980-nm excitation, the aqueous solution of the sample displayed a bright green upconversion (UC) fluorescence. The luminescence dynamics were further studied based on the UC
excitation pathways and the emission processes. Such water soluble UC samples may find application in the field of biological imaging.
Hydrothermal Synthesis and Aspect Ratio Dependent Upconversion Luminescence of NaYF4:Yb3+/Er3+ Microcrystals
Authors: Jiang Tao , Qin Weiping , Zhou Jun
Published: April 2016

β-NaYF4:Yb3+, Er3+ microcrystals of good shape and with various aspect ratios were successfully prepared using a facile hydrothermal method. Field emission scanning electron microscope images and X-ray diffraction patterns were used to characterize
the resulting samples. The upconversion luminescence (UCL) properties of the products were investigated as a function of their aspect ratios. It was found that the proportion of green to red emission intensities increased from 0.8 to 1.4 in the range of aspect ratios 0.04 to 0.9. This study
demonstrates a new strategy for the synthesis of UCL materials with different spectral properties simply by changing their aspect ratios.
Highly Stable Transparent Electrodes Made from Copper Nanotrough Coated with AZO/Al2O3
Authors: Li Peng , Yan Xingzhen , Ma Jiangang , Xu Haiyang , Liu Yichun
Published: April 2016

Due to their high flexibility, high conductivity and high transparency in a wide spectrum range, metal nanowires and meshes are considered to be two of the most promising candidates to replace the traditional transparent conducting films, such as tin doped indium oxide. In this paper,
transparent conducting films made from copper nanotroughs are prepared by the electrospinning of polymer fibers and subsequent thermal evaporation of copper. The advantages of the technique include low junction resistance, low cost and low preparation temperature. Although the copper nanotrough
transparent conducting films exhibited a low sheet resistance (19.2 Ω/sq), with a high transmittance (88% at 550 nm), the instability of copper in harsh environments seriously hinders its applications. In order to improve the stability of the metal transparent conducting films, copper
nanotroughs were coated with 39 nm thick aluminum-doped zinc oxide and 1 nm thick aluminum oxide films by atomic layer deposition. The optical and electrical measurements show that coating copper nanotrough with oxides barely reduces the transparency of the films. It is worth noting that conductive
oxide coating can effectively protect copper nanotroughs from thermal oxidation or acidic corrosion, whilst maintaining the same flexibility as copper nanotroughs on its own.
Effects of Cu Dopant on Lattice and Optical Properties of ZnS Quantum Dots
Authors: Shuhua Lu , Aiji Wang , Tingfang Chen , Yinshu Wang
Published: April 2016

Doped and undoped ZnS colloidal nanocrystals have drawn much attention due to their versatile applications in the fields of optoelectronics and biotechnology. In this paper, Cu doped ZnS quantum dots were synthesized via the simple thermolysis of ethylxanthate salts. The lattice and
optical properties of the nanocrystals were then studied in detail. The quantum dot lattice contracted linearly between Cu concentrations of 0.2–2%, while it continued to contract more gradually as Cu concentrations were further increased from 4 to 6%, due in part to the Cu ions located
on the surface of the ZnS lattice. Cu incorporation induces a long tail in absorption at long wavelengths. The PL spectrum shows a red shift at first, and then a blue shift with increases in Cu concentration. Cu doped at low concentrations (0.2–1%) enhanced the emission, while high Cu
concentrations (2–6%) quenched emissions.
Synthesis, Characterization and Luminescence Properties of Rod-Like LaPO4:Eu3+ Nanostructures
Authors: Peng Li , Yun Liu , Xiaolei Shi , Yaxin Guo , Gangqiang Zhu
Published: April 2016

Large-scale, rod-like nanostructures of LaPO4:Eu3+ phosphors were synthesized using a simple hydrothermal method. The phase composition, structure and morphology of the final products were characterized by XRD, FE-SEM and TEM. Highly crystalline material was obtained
as confirmed by X-ray powder diffraction measurements. The FE-SEM and TEM observations indicate that the obtained LaPO4:Eu3+ nanorods have a diameter of about 10–20 nm, and a length of about 100–600 nm. Meanwhile, the excitation and emission spectra of the
products at room temperature were measured using a fluorescence spectrometer. The effects of pH and Eu3+-doping on the morphology and luminescence properties of the as-prepared powders were investigated. The photoluminescence (PL) spectra show that the emission intensity of the
LaPO4:Eu3+ phosphors improved with increases in concentrations of Eu3+ from 3 mol% to 14 mol%, and then decreased for higher concentrations.
Temperature-Dependent Photoluminescence of Zn–Cu–In–S Quaternary Nanocrystals with Different Reaction Time
Authors: Liu Xiaojuan , Zhang Xiaosong , Li Lan , Zhu Mingxue , Zhou Ping
Published: April 2016

Non-toxic, environment-benign colloidal ZnCuInS Nanocrystals (ZCIS NCs) were synthesized and the temperature dependence of the photoluminescence (PL) energy, line width, and intensity for the ZCIS NCs with different reaction time were studied in the temperature range from 50 to 280
K. Generally, for typical ZCIS NCs ensemble, it has been constantly observed that the PL peaks energy decrease with the experimental temperature raising and the value of Eg(0) decrease with the increase of reaction time. Furthermore, the full width at half maximums (FWHM)
of the PL spectra increased with the experimental temperature raising. It was found that the temperature dependence of the integrated PL intensity of ZCIS NCs decrease with the experimental temperature raising and the intensity decrease much with increasing reaction time.
Photoluminescence Properties Research on Graphene Quantum Dots/Silver Composites
Authors: Wang Jun , Li Yan , Zhang Bo-Ping , Xie Dan-Dan , Ge Juan , Liu Hui
Published: April 2016

Graphene quantum dots (GQDs) possess unique properties of graphene and exhibit a series of new phenomena of 0 dimension (D) carbon materials. Thus, GQDs have attracted much attention from researchers and have shown great promise for many applications. Recently, many works focus on GQDs-metal
ions and metal nanoparticles (NPs). Although, many researches point out that metal ions and metal NPs have significant effect on photoluminescence (PL) feature of GQDs, mainly focus on PL intensity. Here, for the first time, we reported that metal NPs also affected PL peak position which was
dependent on the mix mechanism of metal and GQDs. When GQDs-silver (Ag) composite mixed by physical method and excited at a wavelength of 320 nm, PL peak position of composites first showed blue-shifted then red-shifted with increasing of Ag content. However, if GQDs-Ag composite prepared
by chemical method, PL peak position of the composites blue-shifted. Furthermore, the shift of PL peak position of GQDs-Ag prepared both for physical and chemical method displayed excitation-dependent feature. When the excitation wavelength approached to Ag SPR peaks, no obvious PL shift was
observed. The mechanism for different PL shifts and the phenomenon of excitation-dependent PL shift as well as the formation mechanism of GQDs-Ag composite by chemical method are discussed in detail in this paper.
Electrochemical Tuning of Amorphous Carbon Amount and Surface Oxidation Degree of Graphitic Quantum Dots
Authors: Wang Jun , Li Yan , Zhang Bo-Ping , Ma Ning , Ge Juan , Li Ling , Li Ting , Liu Qian-Qian
Published: April 2016

Graphitic quantum dots (GQDs) have attracted much interesting of researchers because of its amazing optical properties and its ability to be used for many applications. Now, there are various methods have been reported for preparation of GQDs. Among them electrochemical method is simple
technology, while it can afford various conditions to realize controllable prepared of GQDs. In this study, we tuned the PH values of electrolyte to probe the relationship of electrolyte environment and GQDs’ optical properties as well as to seek the effective controllable condition
for GQDs’ preparation. It is found that the density of oxygen-related functional groups and the amount of amorphous carbon of GQDs were related to the PH values of electrolyte. The amount of amorphous carbon decreased as the PH values increased in the region of 6.6 to 7.1. Although,
the positions of photoluminescence (PL) peak almost no changed of GQDs with different density of oxygen-related functional groups, GQDs with the lowest amount of amorphous carbon achieved the maximum PL intensity. Therefore, controlling amorphous carbon’s amount by electrochemical method
may afford a new direction to improve the fluorescence (FL) emission of GQDs.
Surfactant Effect on Formation of CaWO4:Eu3+ Crystals with Distinguished Morphologies in Hydrothermal Ambient
Authors: Chen Ye-Qing , Yang Guo-Tao , Luo Jian-Yi , Yang Ying-Shu , Zeng Qing-Guang , Jeong Jung Hyun
Published: April 2016

Metal tungstates, expressed by the general formula of MWO4, have important properties and applications in photoluminescence, microwave applications, optical fibers, scintillator materials, humidity sensors, magnetic properties, and catalysts. In this paper, we report a successful
synthesis of CaWO4:Eu3+ crystals with various morphologies in mild hydrothermal conditions with surfacntant including sodium citrate, CTAB, PEG and citrate acid (CA). The formation of the crystals are strongly dependent on the employment of surfactant. The surfactant
concentration has been found significant influence in the resulting morphologies due to different properties of each one. Extensive characterization have been performed by using X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM) in search of the formation mechanism
of multi-morphological CaWO4:Eu3+ crystals. The growth mechanism of monodispersed CaWO4:Eu3+ crystal are proposed. And the photoluminescence properties were investigated.
Synthesis, Morphology Control and Luminescent Properties of Rare Earth Ion-Doped CaWO4 Microstructures
Authors: Liu Chunxia , Yang Lixia , Yue Dan , Wang Mengnan , Jin Lin , Tian Boshi , Li Chunyang , Wang Zhenling
Published: April 2016

Rare earth ions (Tb3+, Eu3+) doped CaWO4 microstructures were synthesized by a facile hydrothermal route without using any templates and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL) spectrum.
The results indicate that the asprepared samples are well crystallized with scheelite structure of CaWO4, and the average diameter of the microstructures is 2∼4 μm. The morphology of CaWO4:Eu3+ microstructures can be controllably changed from
microspheres to microflowers through altering the doping concentration of Eu3+ from 3% to 35%, and the microflowers are constructed by a number of CaWO4:Eu3+ nanoflakes. Under the excitation of UV light, the emission spectrum of CaWO4:Eu3+
is composed of the characteristics emission of Eu3+ 5D0-7FJ (J = 1, 2, 3, 4) transitions, and that of CaWO4:Tb3+ is composed of Tb3+ 5D4-7FJ (J = 6, 5,
4, 3) transitions. Both of the optimal doping concentrations of Tb3+ and Eu3+ in CaWO4 microstructures are about 5%.
Viewing the Interaction Between Double Strand Deoxyribonucleic Acid and Graphene Oxide via Atomic Force Microscopy
Authors: Liu R , Wei Z , Hu Z , Li M , Zhao Y
Published: April 2016

The interaction between DNA and graphene-oxide (GO) is fundamental and of significance to a number of biomedical applications. It is fairly clear that π–π stacking effect accounts for the strong interaction between ssDNA and GO, while little is known on the mechanics of
the relative weak interaction between dsDNA and GO. Here we employ AFM to investigate the coupling behavior of dsDNA-GO duplex and reveal preference adsorption of DNAon GO. The results show that dsDNA tends to aggregate on GO surface. Additionally, it is observed that GO also tend to stack
into multilayer structure in the presence of dsDNA, indicating dsDNA can simultaneously interact with two sides of the GO sheet. Such a structure is, however, unstable and can easily collapse by rinsing or heating.
Preparation of Chiral Polydiacetylene Films by Using Three-Photon Polymerization
Authors: Manaka Takaaki , Iwamoto Mitsumasa
Published: April 2016

Asymmetric polymerization of polydiacetylene (PDA) from commercially available achiral derivative of diacetylene monomer using circularly polarized pulse laser is demonstrated. Chiral source was only circularly polarized laser, and irradiation of left- and right-circularly polarized
light effectively promoted the polymerization of chiral PDAs with opposite handedness. Difference between the laser wavelength and the absorption peak of monomer suggested the contribution of the multiphoton excitation to the photo-polymerization. Laser power dependence of the polymerization
rate indicated the possibility of three-photon polymerization.
Interfacial Energy Alignment at the ITO/Ultra-Thin Electron Selective Dielectric Layer Interface and Its Effect on the Efficiency of Bulk-Heterojunction Organic Solar Cells
Authors: Itoh Eiji , Goto Yoshinori , Saka Yusuke , Fukuda Katsutoshi
Published: April 2016

We have investigated the photovoltaic properties of an inverted bulk heterojunction (BHJ) cell in a device with an indium-tin-oxide (ITO)/electron selective layer (ESL)/P3HT:PCBM active layer/MoOx/Ag multilayered structure. The insertion of only single layer of poly(diallyl-dimethylammonium
chloride) (PDDA) cationic polymer film (or poly(ethyleneimine) (PEI) polymeric interfacial dipole layer) and titanium oxide nanosheet (TN) films as an ESL effectively improved cell performance. Abnormal S-shaped curves were observed in the inverted BHJ cells owing to the contact resistance
across the ITO/active layer interface and the ITO/PDDA/TN/active layer interface. The series resistance across the ITO/ESL interface in the inverted BHJ cell was successfully reduced using an interfacial layer with a positively charged surface potential with respect to ITO base electrode.
The positive dipole in PEI and the electronic charge phenomena at the electrophoretic deposited TN (ED-TN) films on ITO contributed to the reduction of the contact resistance at the electrode interface. The surface potential measurement revealed that the energy alignment by the transfer of
electronic charges from the ED-TN to the base electrodes. The insertion of the ESL with a large positive surface potential reduced the potential barrier for the electron injection at ITO/TN interface and it improved the photovoltaic properties of the inverted cell with an ITO/TN/active layer/MoOx/Ag
structure.
Fabrication of Vertical Molecular Junction Devices with Conductive Polymer Contacts Using a Peeling Method
Authors: Konishi Yu , Nagase Takashi , Kobayashi Takashi , Ueda Rieko , Terui Toshifumi , Otomo Akira , Naito Hiroyoshi
Published: April 2016

We present a simple technique for patterning Au top electrodes in vertical molecular junction devices that have the conductive polymer, poly(3,4-ethylene dioxythiophene)-poly(4-styrene sulfonate) (PEDOT:PSS), as a contact layer between the self-assembled monolayer and the Au top electrode.
In this method, a thermally curable photoresist of SU-8 is used to define the areas where the top electrodes are formed. The hydrophobicity and low surface energy of the cured SU-8 facilitates selective deposition of PEDOT:PSS onto the defined top electrode areas of the device through solution
dewetting, and also enables the physical peeling of the Au top electrodes deposited on the SU-8 layers using an adhesion tape. Through this approach, vertical molecular junctions with patterned Au top electrodes can be fabricated without employing the shadow mask evaporation process used in
the conventional approach. We processed vertical molecular tunneling devices based on self-assembled alkanedithiol monolayers with an active area of 100 μm2.
Partial Dissolution of Charge Order Phase Observed in -(BEDT-TTF)2PF6 Single Crystal Field Effect Transistor
Authors: Sakai Masatoshi , Moritoshi Norifumi , Kuniyoshi Shigekazu , Yamauchi Hiroshi , Kudo Kazuhiro , Masu Hyuma
Published: April 2016

The effect of an applied gate electric field on the charge-order phase in β-(BEDT-TTF)2PF6 single-crystal field-effect transistor structure was observed at around room temperature by technical improvement with respect to sample preparation and electrical measurements.
A relatively slight but systematic increase of the electrical conductance induced by the applied gate electric field and its temperature dependence was observed at around the metal-insulator transition temperature (TMI). The temperature dependence of the modulated electrical
conductance demonstrated that TMI was shifted toward the lower side by application of a gate electric field, which corresponds to partial dissolution of the charge-order phase. The thickness of the partially dissolved charge order region was estimated to be several score
times larger than the charge accumulation region.
Molecular Packing Structure of Mesogenic Octa-Hexyl Substituted Phthalocyanine Thin Film by X-ray Diffraction Analysis
Authors: Ohmori Masashi , Higashi Takuya , Fujii Akihiko , Ozaki Masanori
Published: April 2016

The molecular packing structure in a thin film of the liquid crystalline phthalocyanine, 1,4,8,11,15,18,22,25-octahexylphthalocyanine (C6PcH2), which is a promising small-molecular material for solution-processable organic thin-film solar cells, has been investigated by X-ray
diffraction (XRD) measurement. The crystal structure of C6PcH2 in the spin-coated film was determined to be a centered rectangular structure (a= 36.4Å, b 20.3 Å). The tilt angle of the phthalocyanine core normal vector was 34–39° from the column
axis, and the shortest intermolecular distance was 3.9–4.0 Å. The crystal structure determined by XRD analysis was ascertained to be consistent with that calculated by Fourier analysis.
Hybrid Organic–Inorganic Solar Cells with Electrodeposited Al-Doped Zinc Oxide
Authors: Ty Jennifer Torres Damasco , Dannehl Nadine , Schlettwein Derck , Yanagi Hisao
Published: April 2016

Hybrid solar cells were fabricated using aluminum-doped zinc oxide (AZO) grown by electrochemical deposition from chloride electrolyte solutions with Al/Zn molar ratios of 0.5, 2.5, and 5.0%. The substrates were AZO- and ZnO-seeded ITO. Ordered nanorod structures with high optical transmittance
were grown at 0.5% Al/Zn ratio while interconnected micron-sized flakes were grown at 2.5% and 5.0%. The estimated band gap energies increase for higher Al dopant content, showing Burstein-Moss effect. EDX analysis detected high aluminum content in the 5.0% samples suggesting that insulating
aluminum oxide phases were formed thus causing reduced solar cell efficiencies. The highest power conversion efficiency of 1.71%, from the 0.5% sample grown on ZnO-seeded ITO, can be attributed to the presence of AZO nanorods which provide a large interfacial area and effective charge transport.
Investigation of Ultraviolet Light Curable Polysilsesquioxane Gate Dielectric Layers for Pentacene Thin Film Transistors
Authors: Shibao Hideto , Nakahara Yoshio , Uno Kazuyuki , Tanaka Ichiro
Published: April 2016

Polysilsesquioxane (PSQ) comprising 3-methacryloxypropyl groups was investigated as an ultraviolet (UV)-light curable gate dielectric material for pentacene thin film transistors (TFTs). The surface of UV-light cured PSQ films was smoother than that of thermally cured ones, and the
pentacene layers deposited on the UV-light cured PSQ films consisted of larger grains. However, carrier mobility of the TFTs using the UV-light cured PSQ films was lower than that of the TFTs using the thermally cured ones. It was shown that the cross-linker molecules, which were only added
to the UV-light cured PSQ films, worked as a major mobility-limiting factor for the TFTs.
Enhancement of Exciton Emission in Lead Halide-Based Layered Perovskites by Cation Mixing
Authors: Era Masanao , Komatsu Yumeko , Sakamoto Naotaka
Published: April 2016

Spin-coated films of a lead halide, PbX: X = I and Br, layered perovskites having cyclohexenylethyl ammonium molecule as an organic layer, which were mixed with other metal halide-based layered perovskites consisting of various divalent metal halides (for example, CaI2,
CdI2, FeI2, SnBr2 and so on), were prepared. The results of X-ray diffraction measurements exhibited that solid solution formation between PbX-based layered perovskite and other divalent metal halide-based layered perovskites was observed up to very
high molar concentration of 50 molar% in the mixed film samples when divalent cations having ionic radius close to that of Pb2+ were employed. In the solid solution films, the exciton emission was much enhanced at room temperature. Exciton emission intensity of PbI-based layered
perovskite mixed with CaI-based layered perovskite (20 molar%) is about 5 times large that of the pristine PbI-based layered perovskite, and that of PbBr-based layered perovskite mixed with SnBr-based layered perovskite (20 molar%) was also about 5 times large that of the pristine PbBr-based
layered perovskite at room temperature.
Actuation Behavior of Polylactic Acid Fiber Films Prepared by Electrospinning
Authors: Nobeshima Taiki , Ishii Yuya , Sakai Heisuke , Uemura Sei , Yoshida Manabu
Published: April 2016

A poly-DL-lactide (PLA) fiber film was prepared using the electrospinning method. This film consisted of randomly oriented PLA nanofibers. Consequently, it had sponge-like structure and was quite soft compared to PLA films prepared by spin coating. The average diameter of the fibers
and the density of the film were 730 nm and 20%, respectively. By applying a voltage, the PLA film was subjected to electric-field-induced strain: expansion and compression in the thickness direction. When a voltage of −200 V was applied to the film, its thickness shrank from 13.5 μm
to 10.0 μm (a 26% reduction). Electric-field-induced strain can occur via two different mechanisms: The first is electrostrictive behavior. That is, in a highly electric field region, a change of film thickness occurs (compression only) from the electrostatic force between electrodes.
The second mechanism is piezoelectric-like behavior that occurs in racemic PLA, wherein a PLA nanofiber is expanded and compressed by applying positive and negative voltage. Such piezoelectric-like behavior was not observed in spin-coated PLA films.