ZnO-Sm纳米复合物制备及可见光催化降解RhB

采用简单的水热反应后于400℃煅烧3h,制备出正六边形柱状ZnO-Sm纳米颗粒.合成的ZnO材料用紫外-可见光谱仪(UV-vis)、扫描电子显微镜(SEM)、能谱分析仪(EDX)和傅氏转换红外线光谱分析仪(FTIR)表征.SEM扫描图片显示合成的ZnO材料为柱状正六边形纳米颗粒,且随着Sm的掺杂ZnO纳米颗粒的晶体体积变小,但并未改变ZnO晶体形态.EDX图谱证明Sm成功掺杂进入ZnO晶体.光催化实验显示在可见光照射下原子分数2.0%ZnO-Sm纳米材料比纯ZnO纳米材料对玫瑰红B(RhB)的降解效果提高了近30%,并探索了最佳实验条件以获得更好的光催化效果.结果表明ZnO-Sm纳米材料在废水处理中具有潜在的应用价值.

含羧基席夫碱型配合物纳米结构材料的制备及谱学性质研究

采用对氨基苯甲酸分别与对苯二甲醛、间苯二甲醛反应,制备出两种带有端羧基的席夫碱型配体.控制一定条件,与铁、钴、镍、铜、锌等过渡金属配位后得到一系列微观形貌不同的金属配合物纳米结构材料.通过红外、XRD、TEM、SEM等表征手段,考察了相应金属配合物纳米结构材料的结构与性质.用荧光光谱考察配合物纳米结构材料的光致发光性能.发现与原席夫碱型配体相比,大部分配合物纳米结构材料表现出荧光淬灭现象,但含Zn2+的配合物纳米结构材料具有很好的荧光响应,个别甚至优于配体本身的荧光强度,表现为荧光增强效应.以金属配合物纳米结构材料为基底,考察其对探针分子(2-巯基苯并噻唑)的表面拉曼增强(SERS)性能.结果发现,通常具有较粗糙表面的配合物纳米结构材料对探针分子有一定的SERS效应.

Synthesis of Multishell Carbon Nanotube Composites via Template Method

Multishell nanotubes of polyaniline and carbon were synthesized via a template approach. A thin layer of MnO2 coated on carbon nanotubes acts as a reactive template for the consequent formation of the polyaniline coating. The polyaniline-carbon nanotubes show enhanced dispersibility in water and can be possibly used as a functional material of electrochemical capacitors with improved performance. The general method operates by coating carbon nanotubes on functional materials such as poly （3,4-ethylenedioxythiophene）, polypyrrole, silica, and carbon.

Microstructure and photocatalytic activity of Ni-doped ZnS nanorods prepared by hydrothermal method

Pure ZnS and Ni^2+-doped ZnS nanorods (Zn1-xNixS, x=0, 0.01, 0.03, 0.05 and 0.07, mole fraction,%) were synthesized by hydrothermal method. The effects of Ni2+ doping on the phase-structure, morphology, elemental composition and optical properties of the samples were investigated by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), X-ray energy dispersive spectrometry (EDS) and ultraviolet–visible spectroscopy (UV-Vis), respectively. The photocatalytic activity of Zn1-xNixS nanorods was evaluated by the photodegradation of organic dyes Rhodamine B (RhB) in aqueous solution under UV light irradiation. The results show that all samples exhibit wurtzite structure with good crystallization. The morphologies are one-dimensional nanorods with good dispersion, and the distortion of the lattice constant occurs. The band gap of Zn1-xNixS samples is smaller than that of pure ZnS, thus red shift occurs. Ni^2+-doped ZnS nanocrystals can enhance photocatalytic activities for the photodegradation of RhB. Especially, Zn0.97Ni0.03S sample exhibits better photocatalytic performance and photocatalytic stability for the decomposition of RhB.

Template-free hydrothermal synthesis and gas-sensitivity of hollow-structured Cu_(0.3)Co_(2.7)O_(4) microspheres

Hollow-structured Cu_(0.3)Co_(2.7)O_(4) microspheres have been synthesized by a simple one-pot template-free hydrothermal method with copper sulfate,cobalt acetate and ammonia as raw materials.The products were characterized by powder X-ray diffraction,energy dispersive X-ray analysis,selected area electron diffraction,high-resolution transmission electron microscopy,scanning electron microscopy and BET measurements.The research results show that the hollow Cu_(0.3)Co_(2.7)O_(4) microspheres consist of single-crystalline nanocubes with the diameter of about 20 nm.The formation mechanism of hollow Cu_(0.3)Co_(2.7)O_(4) microspheres is suggested as Ostwald ripening in a solid-solution-solid process,and Cu_(0.3)Co_(2.7)O_(4) microspheres are mesoporous containing two pore sizes of 3.3 and 5.9 nm.The as-prepared Cu_(0.3)Co_(2.7)O_(4) sensors have optimal gas responses to 50×10^(−6) mg/m^(3) C_(2)H_(5)OH at 190℃.

Synthesis and Morphological Evolution of CuGaS2 Nanostructures via a Polyol Method

Using ethylene glycol as solvent and reductant, CuCl2-2H2O, （NH2）2CS and self-prepared GaCl3 as the starting materials, CuGaS2 nanostrucutures were synthesized on a large scale at 220℃. Powder X-ray diffraction. transmission electron microscopy, field-emission scanning electron microscope, high-resolution transmission electron microscopy＂ and X-ray＂ photoelectron spectroscopy were used to characterize the products. It demonstrated the evolution of the CuGaS2 particles from spherical assemblies to flowerlike morphology, over time, at 220℃. Simultaneously, we elucidated the specific roles of reaction temperature, reaction time and solvent in the formation of the final CuGaS2 nanostructures. A possible formation mechanism of CuGaS2 nanostrucutures was also discussed. The room temperature photoluminescence spectrum showed blue-shift and an increase of intensity, with a decrease in the sizes of CuGaS2 particles.

Green synthesis of pure and doped semiconductor nanoparticles of ZnS and CdS

Nanoparticles of pure and Cu/Ag-doped CdS and ZnS have been synthesized via chemical bath deposition without using any capping or toxic reagents.The synthesis was carried out through a simple and less expensive green method.The XRD result shows that both pure CdS and ZnS and their doped derivatives are of high crystalline with hexagonal packing structure.The average crystalline size of all nanoparticles was calculated using Debye-Scherrer formula.The crystalline size of nanoparticles of pure samples varied with that of the doped sample.The average crystalline sizes of all nanoparticles are found to be in the range of 5.5-2.2 nm for CdS（from pure to doped） and 4.3-3.4 nm for ZnS,respectively.The band gap values obtained from UV-visible spectra are in the range of 3.5-2.1 e V for CdS and 3.3-2.7 e V for ZnS derivatives,respectively.The FTIR spectral data give characteristic peaks for Cd—S,Cu—S,Ag—S and Zn—S bonds and confirm the formation of respective nanoparticles.The peaks corresponding to the microstructural formation are also observed.The FE-SEM images show the granular morphological structure for all the samples.The agglomeration size of the samples in the range of 10-50 nm for CdS：Cu and 50-100 nm for ZnS：Cu is observed.

Tailoring the surface structures of iron oxide nanorods to support Au nanoparticles for CO oxidation

Iron oxide supported Au nanomaterials are one of the most studied catalysts for low-temperature CO oxidation.Catalytic performance not only critically depends on the size of the supported Au nanoparticles(NPs)but also strongly on the chemical nature of the iron oxide.In this study,Au NPs supported on iron oxide nanorods with different surface properties throughβ-FeOOH annealing,at varying temperatures,were synthesized,and applied in the CO oxidation.Detailed characterizations of the interactions between Au NPs and iron oxides were obtained by X-ray diffraction,transmission electron microscopy(TEM),and X-ray photoelectron spectroscopy.The results indicate that the surface hydroxyl group on the Au/FeOOH catalyst,before calcination(Au/FeOOH-fresh),could facilitate the oxygen adsorption and dissociation on positively charged Au,thereby contributing to the low-temperature CO oxidation reactivity.After calcination at 200℃,under air exposure,the chemical state of the supported Au NP on varied iron oxides partly changed from metal cation to Au0,along with the disappearance of the surface OH species.Au/FeOOH with the highest Au0 content exhibits the highest activity in CO oxidation,among the as-synthesized catalysts.Furthermore,good durability in CO oxidation was achieved over the Au/FeOOH catalyst for 12 h without observable deactivation.In addition,the advanced identical-location TEM method was applied to the gas phase reaction to probe the structure evolution of the Au/iron oxide series of the catalysts and support structure.A Au NP size-dependent Ostwald ripening process mediated by the transport of Au(CO)x mobile species under certain reaction conditions is proposed,which offers a new insight into the validity of the structure-performance relationship.

Recent biomedical applications of bio-sourced materials

Natural anisotropic nanostructures occurring in several organisms have gained more and more attention because of their obvious advantages in sensitivity, stability, security, miniaturization, portability, online use, and remote monitoring. Due to the development of research on nature-inspired bionic structures and the demand for highly efficient, low-cost microfabrication techniques, an understanding of and the ability to replicate the mechanism of structural coloration have become increasingly significant. These sophisticated structures have many unique functions and are used in many applications. Many sensors have been proposed based on their novel structures and unique optical properties. Several of these bio-inspired sensors have been used for infrared radiation/thermal, pH, and vapor techniques, among others, and have been discussed in detail, with an intense focus on several biomedical applications. However, many applications have yet to be discovered. In this review, we will describe these nanostructured materials based on their sources in nature and various structures, such as layered, hierarchical, and helical structures. In addition, we discuss the functions endowed by these structures, such as superhydrophobicity, adhesion, and high strength, enabling them to be employed in a number of applications in biomedical fields, including cell cultivation, biosensors, and tissue engineering.

Microstructure and properties of Al-doped ODS steels prepared by wet-milling and SPS methods

In this paper,15Cr-ODS steels containing 0,1 wt%,2 wt%and 3 wt%Al element were fabricated by combining wet-milling and spark plasma sintering(SPS)methods.The microstructure and mechanical properties of ODS steel were investigated by XRD,SEM,TEM,EBSD and tensile tests.The results demonstrate that the Al addition significantly refines the particle precipitates in the Fe-Cr matrix,leading to the obvious refinement in grain size of matrix and the improvement of mechanical properties.The dispersion particles in ODS steels with Al addition are identified as Al2O3 and Y_(2)Ti_(2)O_(7)nanoparticles,which has a heterogeneous size distribution in the range of 5 nm to 300 nm.Increasing Al addition causes an obvious increase in tensile strength and a decline in elongation.The tensile strength and elongation of 15Cr-ODS steel containing 3 wt%Al are 775.3 MPa and 15.1%,respectively.The existence of Al element improves the corrosion resistance of materials.The ODS steel containing 2 wt%Al shows corrosion potential of 0.39 V and passivation current density of 2.61×10^(−3)A/cm^(2)(1.37 V).This work shows that Al-doped ODS steels prepared by wet-milling and SPS methods have a potential application in structural parts for nuclear system.

Coating for Nano Super Soil-repellency of Cashmere Fabric

The nano-size metal oxide was prepared by the single-disperse technique on liquid phase, and formed sol dusters, its uniform film was covered on the surface of cashmere fibers by coating, and it had good oil repellency and water repellency. The results of IR（infrared） Spectrometer analysis revealed： The nano material combines through the strong bonds with the surface of cashmere fibers by the live groups. These analyses by SEM techniques showed that the nano material was distributed on the fiber surface even, and the nano material formed the strong peak of the regular crystal phase structure using the X-Ray Diffractometry （XRD） to analysis the fabric. The optimum techniques were selected by a series of experiments, coated cashmere fabric not only has preserved original properties of softness and comfort, but also has good properties of Bi-repellency function. Therefore, the technique will have potential appfication in engineers.

Structural and spectroscopic characterization of HgS nanoparticles prepared via simple microwave approach in presence of novel sulfuring agent

Mercury sulfide (HgS) crystals with different morphologies and particle sizes, were obtained via a simple microwave reaction by a new precursor complex, [bis ((2-suphanylphenyl)imino]methylphenol) Hg(II)] ([Hg(C13H11NSO)2]2+). The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet–visible (UV?Vis) spectroscopy. Mercury sulfide nanostructures with different sizes were prepared. The effects of precursor concentration, type of solvent, microwave time, and power on the particle size and morphology were investigated. The results show that the type of solvent and microwave power play key roles in the final size of HgS. Ethylene glycol is the best solvent for the synthesis of very fine particles of HgS, and the best power for the preparation of HgS nanoparticles with uniform size distribution is 900 W. The band gap for HgS nanoparticles calculated by UV–Vis spectrum was 3.2 eV which had about 1.2 eV blue shift in comparison with the band gap of 2 eV for bulk sample.

Effect of pH value and calcination temperature on synthesis and characteristics of Cu-Ni nano-alloys

Cu?Ni nano-alloys were prepared using precursors synthesized by the citrate-gel method. The effects of initial solution pH value and calcination temperature on the composition, crystalline structure, purity, morphology, homogeneity and grain size of Cu?Ni nanoparticles were investigated. Both the parameters significantly affect the crystalline structure, composition and grain size. Cu?Ni alloys prepared at pH value of 1 do not contain impurities, and their compositions are Cu0.42Ni0.58, Cu0.45Ni0.55 and Cu0.52Ni0.48 reduced at 300, 400 and 500 °C, respectively. The grain size grows with the increase of calcination temperature for the precursor prepared at pH values of 1.6 and 3. The Ni content of the alloys gradually increases with the increase of calcination temperature at pH value of 3.

Direct identification of the carbonate intermediate during water-gas shift reaction at Pt-NiO interfaces using surface-enhanced Raman spectroscopy

Noble metal-reducible oxide interfaces have been regarded as one of the most active sites for water-gas shift reaction.However,the molecular reaction mechanism of water-gas shift reaction at these interfaces still remains unclear.Herein,water-gas shift reaction at Pt-NiO interfaces has been in-situ explored using surface-enhanced Raman spectroscopy by construction of Au@Pt@NiO nanostructures.Direct Raman spectroscopic evidence demonstrates that water-gas shift reaction at Pt-NiO interfaces proceeds via an associative mechanism with the carbonate species as a key intermediate.The carbonate species is generated through the reaction of adsorbed CO with gaseous water,and its decomposition is a slow step in water-gas shift reaction.Moreover,the Pt-NiO interfaces would promote the formation of this carbonate intermediate,thus leading to a higher activity compared with pure Pt.This spectral information deepens the fundamental understanding of the reaction mechanism of water-gas shift reaction,which would promote the design of more efficient catalysts.

Electrically induced nanostructuring over large area——a new idea from concept to practice

The paper proposes a novel nano-patterning method called electrically induced nanostructuring, where an external electric field, insteadof the external mechanical pressure, is applied to generate an electrohydrody- namic force acting on the polymer-air interface to drive the polymer＇ s flow into the mold cavities. This electri- cally induced nanostrueturing method no longer requires a large mechanical pressure externally applied for actua- ting the polymer filling in the mold cavities, and has been used to successfully fabricate micro/nano pillar arrays of a high aspect ratio （up to 10）, which have been usually considered to be ＂difficult to fabricate＂ by conventional molding or nanoimprinting processes.

Antitumor activity and biodistribution of DHA-NLC formulation in sarcoma 180-bearing mice

Lipid nanoparticles have become attractive for its prominent properties recent years. In this paper, in vivo anti-tumor efficacy of nanostructured lipid carrier of dihydroartemisinin （DHA-NLC） were evaluated in sarcoma 180-bearing mice model through intraperitoneal （i.p.） administration. In vivo biodistribution was also investigated in Kunming mice bearing S180. Results demonstrated that the intraperitoneally injected DHA-NLC could significantly inhibit tumor growth at the dose levels of 20, 40 and 80 mg/kg, and their inhibition rates were 71.24%, 79.20% and 85.74%, respectively. The biodistribution of DHA after intraperitoneal injection of DHA-NLC in S180-bearing mice is remarkably different from the DHA solution. Therefore, DHA encapsulated in NLC does demonstrate superior anticancer effect to DHA suspension on S 180-bearing mice at the same dose and displayed a dose-dependent antitumor efficacy.

Au nanostructures:an emerging prospect in cancer theranostics

Au nanoparticles have been used in biomedical applications since ancient times. However, the rapid development of nanotechnology over the past century has led to recognition of the great potential of Au nanoparticles in a wide range of applications. Advanced fabrication techniques allow us to synthesize a variety of Au nanostructures possessing physiochemical properties that can be exploited for different purposes. Functionalization of the surface of Au nanoparticles further eases their application in various roles. These advantages of Au nanoparticles make them particularly suited for cancer treatment and diagnosis. The small size of Au particles enables them to preferentially accumulate at tumor sites to achieve in vivo targeting after systemic administration. Efficient light absorption followed by rapid heat conversion makes them very promising in photothermal therapy. The facile surface chemistry of Au nanoparticles eases delivery of drugs, ligands or imaging contrast agents in vivo. In this review, we summarize recent development of Au nanoparticles in cancer theranostics including imaging-based detection, photothermal therapy, chemical therapy and drug delivery. The multifunctional nature of Au nanoparticles means they hold great promise as novel anti-cancer therapeutics.

Recent progress on nanostructured conducting polymers and composites:synthesis,application and future aspects

Conducting polymers （CPs） have been widely investigated due to their extraordinary advantages over the traditional materials, including wide and tunable electrical conductivity, facile production approach, high mechanical stability, light weight, low cost and ease in material processing. Compared with bulk CPs, nanostructured CPs possess higher electrical conductivity, larger surface area, superior electro- chemical activity, which make them suitable for various ap- plications. Hybridization of CPs with other nanomaterials has obtained promising functional nanocomposites and achieved improved performance in different areas, such as energy sto- rage, sensors, energy harvesting and protection applications. In this review, recent progress on nanostructured CPs and their composites is summarized from research all over the world in more than 400 references, especially from the last three years. The relevant synthesizing experiences are outlined and abundant application examples are illustrated. The ap- proaches of production of nanostructured CPs are discussed and the efficacy and benefits of newest trends for the pre- paration of multifunctional nanomaterials/nanocomposites are presented. Mechanism of their electrical conductivity and the ways to tailor their properties are investigated. The re- maining challenges in developing better CPs based nanoma- terials are also elaborated.

Embedding tin disulfide nanoparticles in twodimensional porous carbon nanosheet interlayers for fast-charging lithium-sulfur batteries

Lithium-sulfur(Li-S)batteries have attracted significant attention for their high specific capacity,non-toxic and harmless advantages.However,the shuttle effect limits their development.In this work,small-sized tin disulfide(SnS_(2))nanoparticles are embedded between interlayers of twodimensional porous carbon nanosheets(PCNs),forming a multi-functional nanocomposite(PCN-SnS_(2))as a cathode carrier for Li-S batteries.The graphitized carbon nanosheets improve the overall conductivity of the electrode,and the abundant pores not only facilitate ion transfer and electrolyte permeation,but also buffer the volume change during the charge and discharge process to ensure the integrity of the electrode material.More importantly,the physical confinement of PCN,as well as the strong chemical adsorption and catalytic reaction of small SnS_(2)nanoparticles,synergistically reduce the shuttle effect of polysulfides.The interaction between a porous layered structure and physical-chemical confinement gives the PCN-SnS_(2)-S electrode high electrochemical performance.Even at a high rate of 2 C,a discharge capacity of 650 mA h g^(-1)is maintained after 150 cycles,underscoring the positive results of SnS_(2)-based materials for Li-S batteries.The galvanostatic intermittent titration technique results further confirm that the PCN-SnS_(2)-S electrode has a high Li+transmission rate,which reduces the activation barrier and improves the electrochemical reaction kinetics.This work provides strong evidence that reducing the size of SnS_(2)nanostructures is beneficial for capturing and reacting with polysulfides to alleviate their shuttle effect in Li-S batteries.

Engineering imaging probes and molecular machines for nanomedicine

Nanomedicine is an emerging field that integrates nanotechnology, biomolecular engineering, life sciences and medicine; it is expected to produce major breakthroughs in medical diagnostics and therapeutics. Due to the size-compatibility of nano-scale structures and devices with proteins and nucleic acids, the design, synthesis and application of nanoprobes, nanocarders and nanomachines provide unprecedented opportunities for achieving a better control of biological processes, and drastic im- provements in disease detection, therapy, and prevention. Recent advances in nanomedicine include the development of func- tional nanoparticle based molecular imaging probes, nano-structured materials as drug/gene carders for in vivo delivery, and engineered molecular machines for treating single-gene disorders. This review focuses on the development of molecular imag- ing probes and engineered nucleases for nanomedicine, including quantum dot bioconjugates, quantum dot-fluorescent protein FRET probes, molecular beacons, magnetic and gold nanoparticle based imaging contrast agents, and the design and validation of zinc finger nucleases （ZFNs） and TAL effector nucleases （TALENs） for gene targeting. The challenges in translating nano- medicine approaches to clinical applications are discussed.