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The Cu-Ga-S/ZnS quantum dots (QDs) emitting green-to-red light are successfully synthesized by the conventional hot-injection method. In the preparation process, 1-dodecanethiol (DDT) is not only used as the solvent but also the sulfur precursor and ligand. Therefore, all reactants are additives, which can reduce solution contamination. The peak wavelength of Cu-Ga-S/ZnS QDs' emission can be tuned from 520 to 619 nm by changing Cu/Ga stoichiometry. And these quantum dots have narrow full-width at half maximum wavelength of about 75 nm. Furthermore, a white quantum-dot-based light-emitting diode is obtained by depositing the yellow Cu-Ga-S QDs on a blue InGaN chip.

The hollow polyaniline (PANI) micro/nanospheres are obtained through a simple monomer polymerization in alkaline solution with Triton X-100 Micelles as soft templates. The hollow PANI micro/nanospheres demonstrate rapid and effective removal ability for Chromium (VI) (Cr (VI)) in a wide pH range, and the maximum removal capacity can reach 127.88 mg/g at pH 3. After treated with acid, the used hollow PANI micro/nanospheres have about the similar removal capacity of Cr (VI) from wastewater.

Herein, we report an enhanced tunable broadband wavelength-selective lead sulfide (PbS) film detector integrated with Au-nanorod arrays that were obtained by using an ultrathin open-ended porous titanium dioxide membrane (UOP-TM) as a mask. The responsivity of the PbS films with periodic Au-nanorods exhibits a drastic enhancement by up to 125%–175% due to the enhancement of the localized electromagnetic fields around the gold nanorods. Notably, the location of the strongest enhancement peak of photocurrent shifted from 450 to 980 nm as the height of the Au-nanorods increased from 30 to 120 nm. In addition, the responsivity and detectivity of the hybrid PbS film modified with 90 nm Au-nanorod arrays under laser illumination of 980 nm are as high as 944 mA W−1 and 1.72 × 1010 cm Hz1/2 W−1, respectively. These excellent figures-of-merit of the tunable broadband plasma-enhanced PbS films could be a promising candidate in future wavelength-selective photodetector applications.

A high strain sensor composed of elastomer polydimethylsiloxane (PDMS) and polyaniline (PANI) was fabricated by electrodeposition method for PANI preparation and daubing method for PDMS preparation. This kind of sensor could subject to a large tensile strain (∼50%) and revealed a high gauge factor (54 at 50% strain), which was higher than other sensors reported previously. Also, the sensor displayed a current with a magnitude of mA when applied to 1 V, indicating it didn't need expensive and huge test equipment. Moreover, cyclic strain on the sensor obtained repeatable resistive responses. Its work mechanisms were discussed. The flexible sensor was proved to be useful in sensing strains and other various applications.

In this paper, we fabricate ordered pore array (OPA) Ag film coated glass with the aid of polystyrene sphere (PS) array templates. This kind of OPA Ag coated glass has optical advantages of visible transparency, blue and near-infrared resistance. The average visible transmittance is 68%, including a transmission peak of 78% located at 570 nm, and low average transmittance of 48% in the blue light region that is not damaging to the eyes. The near-infrared light blocking rate is 67%, among which 40% light is reflected directly, indicating the reflection domination.

Large scale and highly ordered vanadium pentoxide (V2O5) nanowire arrays were successfully prepared. The nanowires were arranged parallel in the same direction and formed into a uniform and compact structure by using the improved self-assembly method. The V2O5 nanowire arrays were obtained from the in situ high temperature treatment of VO2(A) nanowire arrays. The as prepared V2O5 nanowire arrays show an excellent light response under visible light irradiation at room temperature. Experimentally, when the incident light intensity is 105 mW cm−2, the arrays exhibit a high responsivity of 160.3 mA W−1, a high detectivity of 6.5 × 108 Jones and a fast response time. These results pave the way for an effective approach to fabricate large-scale ordered semiconductor nanowire arrays and promising photoelectric detectors.

Uniform tellurium nanowires (NWs), nanotubes (NTs) and trifold nanorods (NRs) were synthesized using a facile, environmentally benign solvothermal method with ethylene glycol as solvent, polyvinylpyrrolidone as surfactant and non-hazardous ascorbic acid as a reducing agent. By adjusting the amounts of the surfactant and the reducing agent, Te NWs, NTs and trifold NRs were prepared. The diameter of the Te NWs and NTs are 30–40 nm and 120–150 nm, respectively. A morphology evolution diagram based on different amounts of polyvinylpyrrolidone and ascorbic acid aqueous solution are presented. The effects of temperature are also investigated meticulously. The growth mechanism of the Te NTs and trifold Te NRs are discussed based on the crystallization law. The photoelectrical properties of the Te NWs and trifold Te NRs were measured. The photocurrent and responsivity of the photodetector based on Te NWs are 0.17 mA and 25.8 A W−1, respectively.

The magnetic nanoparticle (NP) chain has attracted great concern due to its potential applications in magnetic recording, electron nano-devices, micro-mechanical sensors, and drug delivery. Here, we demonstrate the controllable preparation of magnetic Ni NP chains using electrochemical corrosion methods. Ni/Cu multi-segmented nanowires (NW) were prepared by alternately depositing Ni and Cu into the pores of an anodic aluminum oxide (AAO) template, then highly uniform Ni NP chains were obtained by immersing Ni/Cu NWs/AAO composite membrane in a 15 wt% NaOH solution for about 50 min. The reaction mechanism is proposed based on electrochemical corrosion, in which Cu serviced as the anode is corroded and Ni serviced as the cathode are retained in the NaOH electrolyte solution. Particle size and separation of the Ni NP chains can be easily adjusted and the smallest particle size and particle spacing reached to 6 nm and 15 nm, respectively. This strategy developed herein can be expected to be general route for the controllable fabrication of metallic NP chains.

Lithium tantalate (LiTaO3) is a very important material with various outstanding properties. In this paper, a LiTaO3 microcube has been successfully synthesized using a hydrothermal method at 220 °C. The microcube is about 1 μm in diameter. The structure is characterized by FESEM, TEM and Raman investigation, and the results suggest that the microcube is constructed by nanolayers. To clarify the growth mechanism of the layered microcube, a time-dependent FESEM investigation is performed. Further investigation of PL, dielectric and ferroelectric properties indicate that there are lots of oxygen related defects among the layers, which is helpful for increasing the Curie temperature. The LiTaO3 microcubes show application potential to be used as a pyroelectric detector material with high performance.

One-dimensional noble-metal Ag nanoparticle chains have been prepared by electrodepositing Ag/Bi superlattice nanowires in a porous anodic alumina oxide (AAO) template and following an annealing process in vacuum. It is found that Bi, as a sacrificial metal, can be removed completely after annealing at 450 °C with a vacuum degree of 10(-5) Torr. The regulation of particle size, shape and interparticle spacing of Ag NP chains has been realized by adjusting the segment length of the Ag/Bi superlattice nanowires and the annealing condition. With an extension of the annealing time, it is observed that Ag particles display the transform trend from ellipsoid to sphere. Our findings could inspire further investigation on the design and fabrication of metal nanoparticle chains.

Based on the mechanism of action, a quantitative structure-activity relationship (QSAR) model for the depuration rate constants (k(d)) of 28 PAHs, 8 PBDEs and 28 PCBs in mussels (Elliptio complanata) was constructed by partial least squares (PLS) regression, following the guidelines for development and validation of QSAR models. For the training set of the QSAR model, r(2) = 0.953, the cross-validated regression coefficient (Q(CUM)(2)) was 0.947. The predicted log k(d) values for the validation set were consistent with the observed values, with a standard error (SE) of 0.160 log units and a squared correlation coefficient (Q(EXT)(2)) of 0.892. Comparatively, the developed QSAR model had good robustness, predictive ability and extended applicability domain. The electrophilicity index (omega), molecular polarizability (alpha), the averages of the negative potentials on the molecular surface ((V) over bar (-)(s)) and the balance parameter of surface potential (tau) were the key parameters governing the logk(d) values in the QSAR model, which indicated that the logk(d) value was mainly related to the partition ability, electrostatic interactions, and van der Waals interactions of compounds.

In this Article, bulk-quantity one-dimensional polyaniline (1D PANI) nanowire/tubes with rough surface were prepared by a simple chemical oxidation method. This kind of PANI nanostructure can not only remove Cr(VI) rapidly and effectively in one step from aqueous solution by reducing Cr(VI) to Cr(III) as well as adsorbing the reduced Cr(III) simultaneously, but also be easily regenerated for reuse. During the removal of Cr(VI) process, the as-synthesized PANI was oxidized from emeraldine salt to pernigraniline, and pernigraniline could be reconverted into emeraldine salt by acid treatment. In addition, the morphology of the PANI was not changed after used for Cr(VI) removal. This study not only provides a facile way to fabricate bulk-quantity 1D PANI nanostructure, but also shows a reproducible material for removal of toxic Cr(VI) from wastewater.

Lipid microtubules with wound ribbon features were fabricated by self-assembling method, and the deposition patterns of colloidal Pd particles on tubular template were investigated. The result indicates that colloidal Pd nanoparticles are preferentially decorated on the helical markings in the interior and on the exterior of preformed tubule and to the edge of loosely helical ribbons to obtain helical deposition features. The multi-bilayer microstructure of tubules can be marked by fine Pd nanoparticles deposited at the edge of helical ribbon. There are the site-specific interactions between lipid tubular template and colloidal Pd particles at the helical edge. A new route was illustrated that colloidal Pd particles firmly attach at the edge of thin flat membranes, and then thin membranes roll up and reassemble into tubule together with particles to form helical deposition patterns. The site-specific deposition of Pd is unbeneficial to obtain the homogeneous metal film on tubules, but it can be utilized to reveal the different chemical nature of lipid molecular assembly.

In this paper, submicrometer-sized Ga–In eutectic alloy particles were dispersed into polymethylmethacrylate (PMMA) matrix by ultrasonic vibration and sedimentation method. The solidification and melting processes of Ga–In eutectic alloy particles were studied by differential scanning calorimeter (DSC). Four endothermal peaks with the onset temperature located at 16, −11, −22, and −27 °C were observed in DSC heating curves, which corresponded to the melting process of the stable Ga–In phase α-Ga(In) and three metastable phases of β-Ga(In), δ-Ga(In) and γ-Ga(In), respectively. The stable phase α-Ga(In) can only be formed when the size of alloy particle was larger than 0.58 μm. Conversely, metastable phases β-Ga(In), δ-Ga(In) and γ-Ga(In) are mainly formed. The result shows that phase structures in Ga–In eutectic alloy are size dependent.

Modular design method for designing and synthesizing microporous metal–organic frameworks (MOFs) with selective catalytical activity was described. MOFs with both nano-sized channels and potential catalytic activities could be obtained through self-assembly of a framework unit and a catalyst unit. By selecting hexaaquo metal complexes and the ligand BTC (BTC=1,3,5-benzenetricarboxylate) as framework-building blocks and using the metal complex [M(phen)2(H2O)2]2+ (phen=1,10-phenanthroline) as a catalyst unit, a series of supramolecular MOFs 1–7 with three-dimensional nano-sized channels, i.e. [M1(H2O)6]·[M2(phen)2(H2O)2]2·2(BTC)·xH2O (M1, M2 Co(II), Ni(II), Cu(II), Zn(II), or Mn(II), phen=1,10-phenanthroline, BTC=1,3,5-benzenetricarboxylate, x=22−24), were synthesized through self-assembly, and their structures were characterized by IR, elemental analysis, and single-crystal X-ray diffraction. These supramolecular microporous MOFs showed significant size and shape selectivity in the catalyzed oxidation of phenols, which is due to catalytic reactions taking place in the channels of the framework. Design strategy, synthesis, and self-assembly mechanism for the construction of these porous MOFs were discussed.

We present an analysis of the interatomic force of Ni nanowires on the basis of the interatomic interaction potential energy curve, which is obtained from the results of in situ high temperature X-ray diffraction in the range of 25–800 °C. Compared with bulk Ni, Ni nanowires have larger interatomic force. Our research offers a simple method of studying the mechanical properties of the nanowires.

Tubular halloysite can be used as a template to fabricate a novel metallized ceramic microstructure through electroless plating. Reduction of Pd ions by methanol is conducted to initiate Ni plating. There is a simultaneous deposition of Ni nanoparticles on the outer surface and discontinuous wires in the lumen site of the halloysite template obtained. The different deposition could be caused by the different composition distribution of ferric oxide impurity in the wall due to the isomorphic substitution during the formation of halloysite template. Its magnetic property is mainly attributed to the Ni nanoparticles, not the wires. The metallized ceramic microstructure has the potential to be utilized as a novel magnetic material.

The nanocomposites consist of nanometer silica fillers embedded in thermoset polymers, which were prepared by means of irradiation of ultraviolet light. The nanomechanic properties had been investigated by load–displacement analysis from nanoindentation experiments. The results obtained showed that the nanoindentation hardness is decreasing and tends to a certain value with increasing indentation depth, the value is among 1.91–4.11 GPa while the nanosilica contents varied from 0 to 5% within nanocomposites. Young’s modulus measured by nanoindentation is higher than the value by tensile test, namely EI = ET 1/4 2: 63 and the enhancement of Young’s modulus due to the presence of nanosilica with the above contents, EI = EI, 0 1/4 1: 7 2: 0 from 1: 8 2: 2 from tensile test, was compared to be consistent with each other in two different methods. So nanoindentation technique has been successfully applied for the valuation of the nanomechanic properties of nanocomposites with nanosilica.

Polycrystalline CdS nanotubes (CNTs) were successfully achieved by a two-step treatment, i.e. (CdS+Cd) nanowires (electrodeposition and sulfuration process in anodic alumina membrane) ⇄ CNTs (dissolution method of removing Cd in 0.5 M HCl). Having been characterized using X-ray diffraction and scanning electron microscopy, the nanowires, the intermediate products, contain Cd and CdS, and have uniform diameters of about 80 nm and lengths of up to 25 μm, which correspond to the pore size and thickness of the membrane used. The average inner and outer diameters of the as-obtained CNTs are respectively 40 and 80 nm via transmission electron microscopy. Selected area electronic diffraction, X-ray diffraction and X-ray photoelectron energy spectroscopy investigations demonstrate that these CNTs with hexagonal wurtzite polycrystalline structure are pure and stoichiometric. The successful synthesis of these semiconductor CNTs may open up new possibilities for studies of fundamental properties and potential applications of semiconductor nanotubes. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

We propose a composite magnetic-barrier structure, which is alternately arranged with two different kinds of magnetic barriers. We theoretically investigate the transport properties for electrons tunnelling through this type of magnetic-barrier structure with and without the interaction of the electronic spin and the magnetic field. It is shown that the composite magnetic barriers greatly enhance the wave-vector filtering properties in contrast to the corresponding non-composite magnetic barriers consisting of two identical magnetic barriers. It is also shown that the composite magnetic barriers exhibit a rather evident electron spin-polarization effect, especially in low-energy region, while the corresponding non-composite magnetic barriers do not possess the electron spin-polarization effect.

This study aimed to investigate the direct effects of advanced glycation end products (AGEs) on the mitochondrial structure and function of SH-SY5Y cells and the possible molecular mechanism(s) underlying mitochondria dysfunction by AGEs. SH-SY5Y cells were cultured in 400 μg/ml of AGE-bovine serum albumin (BSA) for 24 h, and changes in the mitochondrial function of SH-SY5Y cells were analysed as follows. Reactive oxygen species (ROS) were detected using 2′,7′-dichlorodihydrofluorescein diacetate molecular probes. Mitochondrial membrane potential (ΔΨm) was determined by flow cytometry using fluorescent probes. The expression of cytochrome c (Cyt c) protein level was assessed by Western blotting. Mitochondrial structures were observed by transmission electron microscopy. Our results showed that AGE-BSA induced an increase in ROS levels, a decrease in mitochondrial ΔΨm, and the release of Cyt c from mitochondria in SH-SY5Y cells. The mitochondria of SH-SY5Y cells showed remarkable swelling and vacuolisation, but these changes were recovered after pretreatment with neutralising anti-receptor for advanced glycation end products (RAGE) antibody. Our results suggested that AGE-BSA induced mitochondrial dysfunction in SH-SY5Y cells through RAGE pathways. Thus, AGEs are potential mechanistic links between diabetes mellitus and Alzheimer’s disease.

Titanium oxide-Ag composite (TOAC) adsorbents were prepared by a facile solution route with Ag nanoparticles being homogeneously dispersed on layered titanium oxide materials. The as-synthesized TOAC exhibited a remarkable capability for trace Cr(VI) removal from an aqueous solution, where the concentration of Cr(VI) could be decreased to a level below 0.05 mg/L within 1h. We have systematically investigated the factors that influenced the adsorption of Cr(VI), for example, the pH value of the solution, and the contact time of TOAC with Cr(VI). We found that the adsorption of Cr(VI) was strongly pH-dependent. The adsorption behavior of Cr(VI) onto TOAC fitted well the Langmuir isotherm and a maximum adsorption capacity of Cr(VI) as 25.7 mg/g was achieved. The adsorption process followed the pseudo-second-order kinetic model, which implied that the adsorption was composed of two steps: the adsorption of Cr(VI) ions onto TOAC followed by the reduction of Cr(VI) to Cr(III) by Ag nanoparticles. Our results revealed that TOAC with high capacity of Cr(VI) removal had promising potential for wastewater treatment.

Silicon nanoparticles dispersed in 2-propanol were prepared by using an arc plasma with gas flow method in a new designed home-made apparatus. The particles are composed of silicon crystal core covered by oxidized amorphous silicon shell. The composition of the particle surface layer can be modified by preparing the sample in different atmosphere. The particles can be also obtained with different core composition and different size which we need.

The relation between sizes and phase structures of gallium has been studied. Gallium droplets with different sizes dispersed in poly(methyl methacrylate) and silicone oil were studied by differential scanning calorimeter and transmission electron microscopy. The results showed that particles with different sizes corresponded to stable or metastable phases of gallium. The stable phase $\ensuremath{\alpha}$-gallium is dominantly formed when the average size of particles is no less than 0.8 micron, and the metastable phases $\ensuremath{\beta}$-, $\ensuremath{\gamma}$- and $\ensuremath{\delta}$-gallium are mainly formed when the average particle size is 0.8--0.6 micron, 0.6--0.3 micron, and below 0.3 micron, respectively. The phase selection in the solidification process under undercooling is used to explain the results.

Free-standing bamboo-like Ni nanowire arrays with periodic branches have been produced by electrochemical deposition in the pores of layer-by-layer anodic alumina membrane. This method could provid...

Multibranched TiO2 nanotubes have been controllably fabricated through a two-step anodization method. By tailoring the diameter ratio of the stem and branch accurate by multibranched, such as two-,...

Netlike mesoporous alumina membrane with layers of controllable pore size is fabricated by anodization and following chemical etching. All the nanochannels in this mesoporous membrane are connected...

In this study, alumina photonic crystals (PCs) were fabricated by applying a sine-wave current in the anodization of aluminum. The effect of periodic time and peak–peak value of the current on the photonic band gap (PBG) were discussed. By selecting the appropriate experimental conditions, a full-width at half maximum (FWHM) of the PBG of only 18 nm was achieved. The experimental results show that the central position of the PBG was proportional to the periodic time of the current signal in the anodization process. A short periodic time allowed the formation of alumina PCs with a narrow band gap. By changing the peak–peak value of the current, the position of the PBG with a narrow FWHM could also be tuned artificially. The as-prepared alumina PCs showed a linear shift of PBG position and transmittance with the increase of refractive index of the analytes infiltrated into the pores, indicating their potential application in chemical sensing or bio-sensing.

A facile and universal synthetic approach for preparing superlattice nanowire (SLNW) arrays is developed. In this method, two kinds of elements are alternately electrodeposited into the holes of the anodic alumina oxide (AAO) template, automatically in separate electrolytes by a programmed device. This method is not restricted by the relative values of the reduction potentials of the elements, and the deposition of each element can be controlled independently. Three kinds of representative SLNW arrays containing noble-metal material (Ag/Ni), thermoelectric material (Bi/Sb) and magnetic material (Ni/Cu) with adjustable segment length are fabricated successfully.

The size effect of materials on the phase structure has been proved by many experiments, and here for the first time, we proposed a size-temperature phase diagram of gallium (Ga). We found that liquid Ga as well as its solid-liquid phase transition (PT) is size dependent. This PT phenomenon was successfully explained in terms of nucleation theory. The size-temperature phase diagram offered a universal phenomenological explanation for the size-related phase selection of Ga. This finding would enrich the general knowledge about the new phenomena induced by the finite-size effect.

In this letter, treatment of GaAs surface by using dimethylaluminumhydride-derived AlON passivation layer prior to HfO2 deposition is proposed to solve the issue of Fermi level pinning. It has been found that AlON passivation layer effectively suppresses the oxides formation and leads to the Fermi level unpinning at the interface between GaAs and HfO2. Based on analysis from metal-oxide-semiconductor capacitors of Au/HfO2/AlON/GaAs stack, excellent capacitance-voltage characteristics with saturated accumulation capacitance and reduced leakage current have been achieved, which may originate from the decrease in the interface state density and the increase in the conduction band offset.

Fermi level pinning attributed to oxides at the GaAs/high-k interface is a major obstacle to develop GaAs-based metal-oxide-semiconductor devices with high performance. In this letter, thermal nitridation treatment of GaAs surface prior to the high-k deposition is proposed to solve the issue of interface pinning. Results have confirmed that nitridation passivation effectively suppresses the oxides formation and leads to a shift in the Fermi level toward the conduction band minimum on the GaAs surface, which increases the conduction band offset at the GaAs/AlOxNy interface, followed by a saturated accumulation capacitance with reduced gate leakage current.

The effect of nitrogen atom doping on the optical properties and dielectric constant of HfO2 films has been systematically investigated. Spectroscopic ellipsometry was employed to investigate the optical properties of nitrogen incorporated HfO2 films. The values of average oscillator strength and average oscillator position extracted from spectroscopic ellipsometry demonstrated that nitrogen incorporation could influence the dipole oscillator strength and oscillator position of HfO2. A physical model of dipole structures was proposed to verify the enhancement of dielectric constant of HfO2 films by nitrogen incorporation.

The effect of N concentration on the band gap and band offsets of HfOxNy films has been systematically investigated. It was found that the band gap as well as the band offsets of HfOxNy films decreased with the increase of N concentration. When the N concentration reached 16.3%, the conduction band offset (ΔEc) reduced to be 0.88eV, which is smaller than the minimal requirement of ΔEc values for high-k dielectrics and, thus, leads to unacceptably high leakage currents. Therefore, nitrogen concentration should be carefully controlled to guarantee excellent properties of nitrogen incorporated high-k dielectrics.

Effects of nitrogen incorporation on interfacial property, band gap, and band alignments of high-k Y2O3 gate dielectrics have been investigated. It was found that the incorporation of nitrogen into Y2O3 films can effectively suppress the growth of the interfacial layer between Y2O3 and Si substrate. The incorporation of nitrogen into Y2O3 films leads to the reduction of band gap and valence band offset, but not the conduction offset of Y2O3 films. High temperature annealing will help to increase the band gap and valence band offset of YOxNy film due to the release of the interstitial N atoms.

Photonic crystals made of air pores in anodic alumina were prepared by electrochemical oxidation of aluminium and subsequent chemical etching. Optical photographs and transmission spectra prove the existence of a photonic band gap in the optical sprectrum for this porous material. The colour of the sample and the diffraction peak position in the transmission spectra could easily be adjusted in the chemical etching process. This method could provide a possible approach to producing large-area optical photonic crystals cheaply and rapidly.