超声辐射法制备与表征DDP修饰锡纳米微粒

金属纳米微粒因自身特殊的光、电、磁和热力学等性能而在催化、光电装置、信息存储以及润滑等领域中有着广阔的应用前景[1~5],因而制备具有特定性能的金属纳米微粒一直是纳米技术领域中的一个研究热点[6~8]。目前制备金属纳米微粒常用的方法主要包括物理法(机械粉碎[9]、气相沉     

油溶性Ag纳米微粒的制备及表征

Surface modified silver nano particles were synthesized in a mixture solvent of water-alcohol with Pyridinium di-n-octadecyldithio phosphate(PyDDP) as a modification agent. Themorphology and structure of DDP-coated Ag (Ag-DDP) nanoparticles were characterized using X-ray powder diffraction(XRD), Transmission electron microscopy(TEM), Fourier transform infrared spectrum (FT-IR) and Thermo gravimetric analysis(TGA). Anti wear properties of Ag-DDP nano particles were tested using a four-ball tribological testing machine. The disperse properties of Ag-DDP nanoparticles were evaluated in solvents such as chloroform, benzen, toluene, liquid paraffin, distilled water and ethanol. The results show that Ag-DDP nanoparticles disperse in organic solvents, but they don’t disperse in water or ethanol. The good disperse properties in organic solvents enable Ag-DDP nanoparticles to be used as oil additives. The XRD pattern of Ag-DDP nanoparticles indicates that they have fcc crystal structure, and the modification layer can prevent the oxidation of Ag nanocores. TEM graphs show that Ag-DDP nanoparticles have a homogeneous grain distribution; the average diameter is about 15nm. FT-IR and TGA curves indicate that the existence of modification layer can prevent the adsorption of water on the surface of nanoparticles. Tribological tests show that Ag-DDP nanoparticles have good anti-wear properties in liquid paraffin, and they can improve the applied load of base oil.     

油溶性金属Ni纳米微粒的制备与表征

纳米材料的制备、性能与应用已成为近年来的研究热点之一犤１犦。由于在催化、光学和电学材料中的广泛应用，超细单分散的金属微粒的制备与性质已引起人们的广泛兴趣。通常制备金属纳米微粒的方法有两种：一是把固体金属材料分裂为纳米尺寸的颗粒，如机械粉碎、电弧放电及金属原子蒸气沉积犤２犦，用这种方法制备的金属微粒粒径一般都比较大，且粒子尺寸分布宽，另一种是把金属原子制成纳米尺度的颗粒，如乳液聚合法犤３犦、热解犤４犦、γ－射线辐照犤５犦、脉冲电沉积犤６犦和化学还原犤７犦等，这种方法制备的微粒粒径通常分布窄且粒子小…     

超声分散法制备Sn-Cd纳米微粒

用超声分散法制备了Sn-Cd纳米微粒,用XRD和TG/DTA研究了样品的晶型与结构,用TEM观察了样品的形貌,考察了超声功率对纳米颗粒粒径的影响,并在四球机上研究了样品的摩擦学性能.     

油分散性氧化锌纳米微粒的制备及表征

采用直接沉淀法制备了异丁酸修饰纳米氧化锌微粒，用XRD、TEM、XPS、IR、UV-Vis、PL等检测手段对样品进行结构表征。结果表明：所制的样品为纤锌矿结构的氧化锌颗粒，粒度约为20 nm，异丁酸分子与表面锌原子以双齿螯合的形式结合。 Zn(II)2p_3/2的结合能与Zn的标准峰位相比，向低结合能方向移动了1.5 eV，其在可见光区比紫外区的荧光发射显著增强。分散性实验表明，样品在有机溶剂中有良好的分散性。     

银纳米微粒分光光度法测定自来水中痕量二氧化氯

在偏碱性的HN4Cl-NH3·H2O缓冲液中,银纳米微粒在414nm处产生一个吸收峰,ClO2的加入能使其氧化而导致该处的吸光值降低.ClO2浓度在0.01045～0.2090μg/mL范围内与414nm处的吸先度降低值成良好的线性关系.据此建立了银纳米微粒分光光度法测定ClO2的分析方法,用于自来水中ClO2含量的测定.     

亲油性AgCl纳米微粒的制备与表征

利用表面修饰方法在乙醇_水混合溶液中合成了双十八烷氧基二硫代磷酸盐修饰的AgCl纳米微粒 ,并用TEM、FT -IR、TG、XRD等仪器对其形貌、表面键合结构、热力学稳定性及晶体结构进行了表征 .结果表明 :双十八烷氧基二硫代磷酸盐与AgCl之间发生了化学键合作用 ,其亲油性大大改善 ,能在氯仿、四氢呋喃中均匀分散为澄清溶液 ,表面修饰层的存在有效地阻止了纳米粒子之间的团聚现象 ,因而粒径比较均匀 ,多数在 30nm左右     

表面修饰LaF_3纳米微粒的制备及表征

在水醇混合介质中采用同阳离子共沉淀表面修饰法制备了有机化合物表面修饰的LaF3纳米微粒 ,研究了它的摩擦学特性。采用多种分析手段表征了表面修饰LaF3纳米微粒的结构 ,并在四球摩擦试验机上考察其润滑性能。结果表明 ,表面修饰LaF3纳米微粒不仅在有机溶剂中具有良好的分散性 ,同时也显示出良好的减摩、抗磨和承载性能。     

油酸修饰PbO纳米微粒的合成及结构表征

利用表面修饰法合成了表面为油酸所修饰的PbO纳米微粒 ,并用红外光谱、X -射线光电子能谱、透射电子显微镜和热分析仪对产物的结构、形貌及化学状态及热稳定性进行了研究 .结果表明 :所制备的PbO纳米微粒大小均匀 ,粒径约为 5nm ,在有机溶剂及石蜡油中的分散性良好 ;表面修饰剂与纳米微粒表面之间发生化学键合作用 ,这使得PbO纳米微粒在有机溶剂及基础油中的分散性得以改善 ,并使得表面修饰层的热稳定性得以明显提高     

亲油性硫化锰纳米微粒的化学制备和结构

采用表面修饰的方法,在醇水体系中制备了双十八烷基二硫代磷酸（DDP）表面修饰的硫化锰（MnS）纳米微粒,用XPS、FTIR、TGA、TEM和HREM等技术对用表面修饰法得到的MnS纳米微粒的结构、化学稳定性和热稳定性进行研究,结果表明：表面修饰得到的MnS纳米微粒有较好的化学稳定性和热稳定性,并且微粒的分散件好、不团聚,制备出的MnS纳米晶核具有γ－MnS的晶型结构。     

不同形貌ZnO纳米粒子的超声化学法制备与表征

One-dimensional ZnO nanorods and shuttle-like ZnO nanoparticles have been successfully achieved by ultrasonic irradiation of Zn (CH3COO)2 aqueous solution and Zn-NH3 complexcs solution. The obtained ZnO nanoparticles have been characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and selected area electronic diffraction (SAED). And the formative mechanism of the prepared different morphological ZnO nanoparticles is also discussed under ultrasonic irradiation.     

光还原法制备不同形貌银纳米粒子及其形成机理

光还原法制备不同形貌银纳米粒子及其形成机理;光还原;纳米银;形成机理     

银纳米微球和银纳米棒自组装膜的制备及SERS研究

采用硼氢化钠还原硝酸银,用振荡器在不同转速下振荡得到单分散的银纳米微球和银纳米棒,再将银纳米微球及银纳米棒自组装于被3-氨丙基-三甲氧基硅烷(APTMS)修饰的玻璃基片上,制得了具有表面增强拉曼(SERS)活性的基底,分别以罗丹明6G(R6G)和罗丹明B(RB)为探针分子对这两种基底进行SERS活性检测,结果发现这两种基底均为较理想的SERS衬底。     

Reconstruction of Silver Nanoplates by UV Irradiation: Tailored Optical Properties and Enhanced Stability

The size and shape of it : The optical properties of Ag nanoplates can be precisely tuned in a wide range through a UV‐light‐induced reconstruction process in which the morphology of the nanoparticles is changed from thin triangular plates to thick round plates (see picture). This unconventional “backward tuning” strategy is a practical route to stable silver nanoplates that display a wide range of plasmon wavelengths.

     

Preparation of Hybrid Microgels Functionalized by Silver Nanoparticles

Summary: Hybrid microgels functionalized with silver nanoparticles (AgNP) have been prepared and their physico‐chemical properties examined. Composite particles have been obtained by formation of AgNP in presence of poly[vinylcaprolactam‐co‐(acetoacetoxyethyl methacrylate)] (VCL/AAEM) microgel particles. It has been demonstrated that hybrid particles with different AgNP amounts can be prepared. Hybrid particles are sensitive to temperature and swelling, and collapse processes are reversible. Incorporation of AgNP leads to shrinkage of microgel template due to the partial immobilization of polymer chains on the microgel surface. As a consequence, gradual loss of temperature sensitivity is observed. Hybrid microgels form highly transparent well‐organized films on solid substrates, providing homogeneous distribution of AgNP in bulk material. Presence of AgNP increases considerably the thermal stability of composite films.

Schematic representation (left) and TEM image (right) of hybrid microgels containing silver nanoparticles (AgNP).     

四硫富瓦烯衍生物修饰的银溶胶

四硫富瓦烯衍生物修饰的银溶胶;银溶胶;纳米粒子;四硫富瓦烯;氧化还原;表面修饰     

The Effect of the Conditions of Catalytic Synthesis of Nanoparticles of Metallic Silver on Their Plasmon Resonance

The formation of nanoparticles of metallic silver in the reduction of Ag⁺ ions catalyzed by colloidal Ag₂S was investigated. It was established that the position of the surface plasmon resonance bands of the Ag nanoparticles is affected by the concentration of the catalyst, its particle size and the amount of particles with the same size, the stabilization conditions, the concentration of Ag⁺ ions, and the temperature at which the process is conducted. An explanation for the spectral changes that occur is proposed.     

单分散性银纳米粒子的可控制备

以卤化银或氧化银作为前驱体,室温下以水为溶剂,在较高溶液浓度下,利用化学还原法制备了单分散性银纳米粒子,并通过改变前驱体的种类,实现了粒径可控制备。采取扫描电子显微镜（SEM）、紫外-可见光谱仪（UV-Vis）、X射线-粉末衍射仪（XRD）、X射线-光电子能谱仪（XPS）等对所制备的银纳米粒子的形貌及成分进行了表征。结果显示,所制备的银纳米粒子具有较高的单分散性,粒径在40~150 nm之间,具有面心立方多晶结构。该方法制备的银纳米粒子可用于喷墨打印RFID天线。     

In-Situ Formation of Silver Nanoparticles in PEI

Nanocomposites consisting of spherical particles of Ag were prepared using a single step in situ method whereby Ag is introduced into the dissolved polymer via dissolution as the organometallic complex Ag TFA in the same solvent as the polymer. The kinetic rate of formation of the particles is determined using WAXS and SAXS measurements. Nanoparticle formation is found to depend on reducing the solvent/polymer ratio, which leads to de-solvating the metal complex. This destabilizes the metal precursor complex, causing it to degrade and the metal particles to phase separate by a thermodynamic driving force. The size of the nanoparticles varies with the cure temperature and the conditions affecting molecular mobility.     

纳米银形状控制合成与聚合物纳米银复合材料

纳米银(Ag NPs)由于其独特的物理、化学和生物学特性备受研究人员的关注.纳米银应用性能除了受到粒子尺寸、分布、纯度等因素影响,还与纳米银的形状密切相关.纳米银的形状对纳米银的抗菌性能、光学性能以及聚合物纳米银复合材料的综合性能都会产生重要影响.纳米银的形状控制合成可以进一步发挥聚合物纳米银复合材料的性能潜力.因此,不断发展纳米银新的合成方法,研究纳米银形状控制的机理就显得尤为重要.本文综述了纳米银合成方法和不同形状纳米银的最新研究进展,合成方法重点介绍了辐射法、激光烧蚀法、电化学法、光化学法和生物合成法,评述了这些方法的优缺点;同时从模板法、动力学、热力学以及氧化刻蚀4个方面介绍了纳米银形状控制的机理.介绍了聚合物纳米银复合材料的研究进展.