纯钛表面载银微弧氧化陶瓷膜的制备及性能EI北大核心CSCD

将微弧氧化和水热处理相结合,在纯钛表面制备载银微弧氧化陶瓷膜,改善其润湿性及耐蚀性,并赋予抗菌性。采用扫描电子显微镜(SEM)、能谱分析(EDS)、X射线衍射(XRD)、X射线光电子能谱分析(XPS)对微弧氧化陶瓷膜层进行表征,通过接触角测试评价膜层亲水性,采用电化学测试对膜层耐蚀性进行评价,抗菌性实验分析膜层抗菌性。结果表明:载银微弧氧化陶瓷膜的表面形貌仍为火山多孔结构,纳米级Ag颗粒均匀分布在微孔周围。载银微弧氧化陶瓷膜的表面主要为TiO2和纳米Ag颗粒。载银微弧氧化陶瓷膜的亲水性比纯钛的亲水性高77.0%,比微弧氧化陶瓷膜的高68.2%。与纯钛相比,载银微弧氧化陶瓷膜的自腐蚀电位提高了0.44 V,与微弧氧化相比增加了0.31 V。微弧氧化陶瓷膜的抗菌率为32.2%,载银微弧氧化陶瓷膜的抗菌率大于99.9%。     

纯钛表面载银微弧氧化陶瓷膜的制备及性能

将微弧氧化和水热处理相结合,在纯钛表面制备载银微弧氧化陶瓷膜,改善其润湿性及耐蚀性,并赋予抗菌性。采用扫描电子显微镜(SEM)、能谱分析(EDS)、X射线衍射(XRD)、X射线光电子能谱分析(XPS)对微弧氧化陶瓷膜层进行表征,通过接触角测试评价膜层亲水性,采用电化学测试对膜层耐蚀性进行评价,抗菌性实验分析膜层抗菌性。结果表明:载银微弧氧化陶瓷膜的表面形貌仍为火山多孔结构,纳米级Ag颗粒均匀分布在微孔周围。载银微弧氧化陶瓷膜的表面主要为TiO_2和纳米Ag颗粒。载银微弧氧化陶瓷膜的亲水性比纯钛的亲水性高77.0%,比微弧氧化陶瓷膜的高68.2%。与纯钛相比,载银微弧氧化陶瓷膜的自腐蚀电位提高了0.44 V,与微弧氧化相比增加了0.31 V。微弧氧化陶瓷膜的抗菌率为32.2%,载银微弧氧化陶瓷膜的抗菌率大于99.9%。     

单分散小尺寸(≤10nm)银颗粒的制备与应用

小尺寸(≤10nm)的银颗粒因具有高的比表面能和化学活性,在药物、光学、催化、磁性材料等领域具有广阔的应用前景。主要评述了单分散小于10nm银颗粒的主要制备方法:常规保护剂法、有机溶剂热还原法、反胶束法、辐射法、电化学还原法等。详细介绍了这些方法的反应机制和研究进展,以及银纳米颗粒在催化、光学、抗菌药等领域的研究开发应用;分析了实现生产银颗粒工业化发展方向。     

单分散小尺寸（≤lOnm）银颗粒的制备与应用

小尺寸（≤lOnm）的银颗粒因具有高的比表面能和化学活性，在药物、光学、催化、磁性材料等领域具有广阔的应用前景。主要评述了单分散小于lOnm银颗粒的主要制备方法：常规保护剂法、有机溶剂热还原法、反胶束法、辐射法、电化学还原法等。详细介绍了这些方法的反应机制和研究进展，以及银纳米颗粒在催化、光学、抗茵药等领域的研究开发应...     

抗菌羟基磷灰石的一步合成及其表征

采用共沉淀法制备羟基磷灰石(HAP),将硝酸银均匀加入反应体系中,通过温度、酸度和搅拌状态控制实现一步合成载银羟基磷灰石(Ag/HAP),该法操作简单,载银均匀,载银量易于控制,克服离子交换法和机械混合法载银的不足,其载银机理包括共沉淀和离子交换载银。所得Ag/HAP经750℃高温处理,未见分解,其结晶度提高,用最小抑菌浓度法(MIC)测得Ag/HAP对大肠杆菌和金黄色葡萄球菌有良好的抑菌性,其最小抑菌浓度为7.385×10-5。     

载银羟基磷灰石抗菌织物的研究

通过硝酸钙和磷酸钠水溶液反应合成了磷灰石纳米浆料，并进一步制备出载银羟基磷灰石粉料。用透射电镜、红外光谱仪和转靶X射线衍射仪对载银羟基磷灰石进行了形貌和物相等分析，用原子吸收光谱仪测定了载银羟基磷灰石粉料Ag^ 含量，并利用后整理法加工出载银羟基磷灰石抗菌织物，对载银羟基磷灰石粉料和织物均进行了抗菌效果的测试。结果表明，载银羟基磷灰石粉料和织物均有很强的抑菌效果，市场应用前景十分广阔。     

载银沸石对纸张抑菌防霉性能及 印刷适性的影响

研究了不同添加质量(或添加质量浓度)的载银沸石对牛皮纸、白卡纸和铜版纸的抑菌防霉效果及机械性能、白度、平滑度等印刷适性的影响。结果表明:1)当纸张中载银沸石的添加质量浓度为1000mg/L时,大肠杆菌的抑菌环直径达21.5mm,由此可知,载银沸石能较好地抑制大肠杆菌的生长。2)当纸张中载银沸石的添加质量为1.0g时,纸张完全无霉菌生长,且纸张边缘的菌丝也未见长出,由此可知,载银沸石对黑曲霉具有一定的抑制效果。3)不同添加质量的载银沸石对纸张的机械性能、白度和平滑度有一定影响,但影响较小。故当载银沸石的添加质量为0.5～1.0g时,纸张不仅具有较好的抑菌防霉效果,且其机械性能、白度和平滑度没有明显变化。     

银纳米粒子负载的石墨烯基环氧树脂复合材料的制备及性能

本工作以鳞片石墨为原料采用Hummer方法制备了石墨烯,并通过原位还原法在石墨烯上负载银纳米粒子,再利用得到的载银石墨烯材料与环氧树脂进行复合,充分发挥了三种材料的优势,得到了性能优异的载银石墨烯基环氧树脂复合材料。同时本工作探究了载银石墨烯的不同掺入比对复合材料拉伸强度和断裂伸长率的影响。结果表明,掺入0.05%(质量分数,下同)载银石墨烯时,复合材料的拉伸强度显著提高,而掺入0.1%载银石墨烯时,复合材料的断裂伸长率增大效果明显。通过对固化温度的研究得出100℃固化温度、载银石墨烯掺入0.05%为最优制备方案。同时,改性后的复合材料能有效减缓环氧树脂的受热分解问题,使环氧树脂的热稳定性得到了提高。     

产品名称：比表面及孔径分析仪

特点： 适合比表面及孔径分析,尤其对中大比表面和孑L隙发达的样品分辨率、准确度高,适合催化剂、分子筛等多孔、比表面较大样品的比表面及孔径分布分析测试。     

载银沸石的制备及其在牛皮纸上的应用研究

采用离子交换法制备了载银沸石抗菌剂,并在质量分数为2%的PVA中添加不同浓度的载银沸石抗菌剂,制备了抗菌牛皮纸,研究了不同抗菌剂添加量下抗菌牛皮纸的厚度和定量的变化及抑菌与防霉效果。结果表明:制得的载银沸石中银离子含量较高,且沸石的基本结构未被破坏;添加载银沸石使纸张的厚度和定量略有增大,且当100mL质量分数为2%的表面施胶剂中载银沸石的添加量为0.5g时,抗菌牛皮纸对大肠杆菌的抗菌率达到99.94%,并能有效抑制黑曲霉菌的生长。     

Nanosilver particle formation on a high surface area titanate

Titanium based molecular sieves, such as ETS-10, have the ability to exchange silver ions and subsequently support self assembly of stable silver nanoparticles when heated. We report that a high surface area sodium titanate (resembling ETS-2) displays a similar ability to self template silver nanoparticles on its surface. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show high concentrations of silver nanoparticles on the surface of this sodium titanate, formed by thermal reduction of exchanged silver cations. The nanoparticles range in size from 4 to 12 nm, centered at around 6 nm. In addition to SEM and TEM, XRD and surface area analysis were used to characterize the material. The results indicate that this sodium titanate has a high surface area (>263 m2/g), and high ion exchange capacity for silver (30+ wt%) making it an excellent substrate for the exchange and generation of uniform, high-density silver nanoparticles.     

Preparation of micron size flake silver powders for conductive thick films

The preparation of micron size flake silver powders with chemical-mechanic method was investigated. Reaction of silver nitrate with ascorbic acid gives fine spherical silver powders. The spherical silver powders were processed by globe mill to make micron size flake silver powders having excellent dispersability and uniform shape. The XRD and thermal analyzer were employed to analyze as—prepared flake silver powders. The flake silver powders were employed to make polymer silver thick film and fire-type thick film. The application of small molecule surfactant in the stage of synthesizing precursor and large specific area of flake particles give a low resistivity of polymer thick film. The fire-type silver thick film was studied by SEM and EDX. SEM photograph shows that the grain boundaries of silver are prominently visible, and the densification of the fired thick film is high. The fire-type thick film has a low bulk resistivity and high adhesion strength.     

Paper-based nanosilver conductive ink

Monolayer-protected silver nanoparticles sized 5 nm were directly synthesized in relatively high concentration (0.093 M) in water phase using cheap chemicals. The ink (20 % silver) prepared with the silver nanoparticles was written on sulfuric paper by a facile pen-on-paper paradigm. The effect factors on the formation and conductive mechanism of the nanosilver films from the silver ink were studied, including the microstructure, size evolution and interaction of particles and so on. Results show that the silver nanoink allows for a low sintering temperature and with a relatively high conductivity. The grown particle, increased inter-particle contact area and off dodecanoic acid layer were the three dominating factors responded to the conductivity of the nanosilver films.     

纳米银导电油墨的制备研究与包装应用概论

纳米导电油墨具有独特的物理及化学性质,而导电填料则决定导电油墨的性能。概述了纳米导电油墨的组成、分类及特点,主要论述了纳米银的特性,相较于其他填料,纳米银具备良好的导电性、导热性、纳米光学性、高比表面积等特性,因而纳米银作为导电填料成为了制备导电油墨的首选;进一步阐述了纳米银的制备方法及纳米银导电油墨的配方设计及制备工艺,通过不同的研究分析了纳米银导电油墨性能的影响因素,以及纳米银导电油墨在不同包装应用的发展趋势,并对其应用研究提出了建议。     

One Dimensional Silver‐based Nanomaterials: Preparations and Electrochemical Applications

One dimensional (1D) silver‐based nanomaterials have a great potential in various fields because of their high specific surface area, high electric conductivity, optoelectronic properties, mechanical flexibility and high electro‐catalytic efficiency. In this Review, the preparations of 1D silver‐based nanomaterials is classified by structure composed of simple silver nanowires/rods/belts/tubes, core‐shells, and hybrids. The latest applications based on 1D silver nanomaterials and their composite materials are summarized systematically including electrochemical capacitors, lithium‐ion/lithium‐oxygen batteries, electrochemical sensors and electrochemical catalysis. The preparation process, tailored material properties and electrochemical applications are discussed.     

Submicrometer spatial resolution of metal-enhanced fluorescence

Enhanced fluorescence emission intensity from fluorescein was observed on glass slides covered with thin films of silver nanoparticles using a confocal laser-scanning microscope. The silver nanoparticle film increased the emission intensity of fluorescein by an average of at least three-fold in the area studied. Statistics are given on the enhancement of individual areas of the silver particle film with a resolution of approximately 210 nm. A histogram of intensity values indicates that the enhancement appears to occur without distinct subpopulations, with the exception that very high intensity subpopulations may occur but could not be resolved. Spatial features with dimensions near or smaller than the resolution limit of the confocal microscope, on the silver nanoparticle slide that enhanced the emission of fluorescein, were found using autocorrelation functions. These spatial features are of the same size as those found from the emission of slides containing silver nanoparticles only. These spatial features do not appear in control slides containing fluorescein without any silver nanoparticles. No long-range spatial ordering of the fluorescence enhancement on chemcially deposited silver nanoparticle slides was detected.     

Polyurethane–silver fibers prepared by infiltration and reduction of silver nitrate

Silver-incorporating polyurethane fibers were prepared by infiltration of silver nitrate on electrospun polyurethane fibers and reduction with sodium borohydride. They were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray system. The Ag nanoparticles prepared by reduction of silver nitrate showed nano-sized crystals of 4–10 nm in diameter. However, larger aggregated Ag particles of 50–200 nm were also found to be dispersed in the polyurethane matrix when Ag particles were formed in electrospun fibers by the infiltration–reduction process of silver nitrate. As a result, infiltration method of silver nitrate into the electrospun fibers was significantly effective to produce silver-incorporating fibers due to a high specific surface area of fibers.     

Large-scale synthesis of single crystal silver nanowires by a sodium diphenylamine sulfonate reduction process

Silver nanowires with high aspect ratios of up to more than 60 were synthesized on a large scale by the redox reaction between silver nitrate and sodium diphenylamine sulfonate at room temperature and in the absence of surfactant and hard-template and seed. When the molar ratio of reductant sodium diphenylamine sulfonate and silver nitrate < or =1, most products were all the nanowires. When the molar ratio increases to 2:1, silver nanowires and nanobelts were concomitantly formed. The redox product N, N'-diphenylbenzidinedisulfonate and sodium diphenylamine sulfonate all play an important role in the formation of silver nanostructures. The structure, morphology, and composition of the silver nanowires were characterized by the X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray energy dispersive microanalysis (EDX), and UV-Vis spectroscopy respectively. High-resolution transmission microscopy (HRTEM) and selected area electron diffraction (SAED) reveal the single-crystal nature of the silver nanowires.     

Large scale, highly conductive and patterned transparent films of silver nanowires on arbitrary substrates and their application in touch screens

The application of silver nanowire films as transparent conductive electrodes has shown promising results recently. In this paper, we demonstrate the application of a simple spray coating technique to obtain large scale, highly uniform and conductive silver nanowire films on arbitrary substrates. We also integrated a polydimethylsiloxane (PDMS)-assisted contact transfer technique with spray coating, which allowed us to obtain large scale high quality patterned films of silver nanowires. The transparency and conductivity of the films was controlled by the volume of the dispersion used in spraying and the substrate area. We note that the optoelectrical property, σ(DC)/σ(Op), for various films fabricated was in the range 75-350, which is extremely high for transparent thin film compared to other candidate alternatives to doped metal oxide film. Using this method, we obtain silver nanowire films on a flexible polyethylene terephthalate (PET) substrate with a transparency of 85% and sheet resistance of 33 Ω/sq, which is comparable to that of tin-doped indium oxide (ITO) on flexible substrates. In-depth analysis of the film shows a high performance using another commonly used figure-of-merit, Φ(TE). Also, Ag nanowire film/PET shows good mechanical flexibility and the application of such a conductive silver nanowire film as an electrode in a touch panel has been demonstrated.     

Protein‐Bound Freestanding 2D Metal Film for Stealth Information Transmission

The welding and sintering of nanomaterials is usually achieved at high temperatures and high pressures. Here, it is found that merging of metal nanoparticles occurs under ambient conditions in an aqueous solution via protein bonding. It is discovered that the silver nanoparticles from the in situ reduction of silver ammonium ions by glucose undergo confined nucleation and growth and are bound by ultrathin amyloid‐like β‐sheet stacking of lysozyme. This merging of silver nanoparticles creates a freestanding large‐area (e.g., 400 cm²) 2D silver film at the air/water interface with a purity up to 98% and controls nanoscale thickness. This reaction system is general to other proteins and metals, and shows the great ability for controlled synthesis of highly reflective and highly conductive silver films with elongation nearly 10 times higher than that of pure metal without protein bonding. The ultrathin protein‐bonding layer functions as a key mediator to dynamically tune the silver conductance in response to external pressures and strains. The sensors exhibit ultrasensitive capability for stealth transmission of Morse code and for silent speech recording via the detection of tiny vibrations of the human throat. This approach will shed light on the development of protein bonding of a given material for bespoke functions.