用于光催化抗菌涂料的纳米TiO2的制备及改性方法

纳米TiO2光催化抗菌涂料是研究热点,其中纳米TiO2抗菌粒子的制备及处理十分重要。介绍了纳米TiO2的抗菌机理及常用的纳米TiO2抗菌粒子制备方法,并从增强纳米TiO2对可见光响应性方面对TiO2的改性方法进行了综述,同时对纳米TiO2在光催化抗菌涂料中的发展前景进行了展望。     

金纳米粒子的最新研究进展

金纳米粒子是最稳定的金属纳米粒子之一，由于其具有优良的稳定性和光学性质，使其在许多领域有着广阔的应用前景。本文主要对金纳米粒子和表面修饰金纳米粒子的制备方法进行分析总结，指出各种方法的制备原理及特点。同时，阐述了金纳米粒子的一些特殊性能，如：表面吸收带效应、荧光效应、量子尺寸效应、单电子跃迁等。并对金纳米粒子的应用进行了展望。     

核壳结构二氧化硅/磁性纳米粒子的制备及应用

核壳结构二氧化硅/磁性纳米粒子作为一种新型功能复合材料在生物医学方面有重要应用前景.综述了核壳结构二氧化硅/磁性纳米粒子的各种制备方法以及国内外在核壳结构二氧化硅/磁性纳米粒子制备方面的研究新进展,并对其在生物医学上的应用作了介绍.     

AgBr／I纳米粒子及其乳剂的制备

综述了ＡｇＢｒ／Ｉ纳米粒子及其乳剂的制备方法，概述了各种纳米粒子乳剂的ＡｇＢｒ含量、感光度及增感情况，并对各种制备方法的应用方向和纳米粒子乳剂的应用前景作了讨论。     

金纳米粒子的制备及自组装

金纳米粒子以它独特的光学、电学和催化性质以及在纳米级电子线路中的应用潜力,受到人们越来越多的关注.本文主要评述了金纳米粒子的合成方法和自组装技术,即对各种制备方法和自组装的特点、纳米粒子的生长机理和自组装机理进行了介绍.展望了金纳米材料未来的研究方向和发展趋势.     

反相微乳技术在纳米粒子制备中的应用

综述了反相微乳液的组成特点以及利用反相微乳液技术制备纳米微粒材料的基本方法;对当前利用反相微乳技术制备金属、金属氧化物、有机聚合物等各种纳米颗粒材料的研究现状进行了讨论,并对反相微乳液技术制备纳米粒子的各种影响因素进行了归纳总结.     

金属纳米粒子氧化行为的计算机模拟研究进展

金属纳米粒子在新材料研究领域中有着广泛的应用。人们对金属纳米粒子的氧化行为通过理论和实验进行了深入的研究,其中计算机模拟研究是非常重要的方法。本文简要介绍了微观尺度层次上的计算机模拟方法,在此基础上综述了国内外金属纳米粒子氧化行为的计算机模拟研究进展。     

CdS纳米粒子的制备方法

CdS纳米粒子作为一种十分重要的光电功能材料，近年来引起人们的广泛关注，各种各样的制备方法也由此应运而生。因制备方法不同，所得CdS纳米粒子的粒径、粒度均匀性、纯度及相结构等也各不相同，并进而会对它们的属性（如光电性质）产生很大的影响。如何以材料的形式付诸应用，依据功能的需求，实现对半导体纳米粒子的粒径、形状、粒度均匀性分布以及纯度等的控制是目前CdS纳米粒子制备方法的发展方向。     

贵金属纳米粒子及其复合物的非线性光学性能和应用研究进展

具有非线性光学特性的贵金属纳米粒子受到广泛的关注,因为这类金属纳米粒子及其复合物不仅具有重要的理论研究意义而且在非线性光学器件方面具有重要的潜在应用价值.对这类金属纳米粒子的主要制备方法、光学特性以及在激光防护等非线性光学器件方面的应用研究进展进行了综述,并对未来的研究和尚存在的问题进行了分析和展望.     

纳米/微米结构粒子合成技术进展

介绍了近年来纳米/微米结构粒子的合成技术进展,将纳米单元(纳米棒、纳米带、纳米片、纳米颗粒)自组装为各种尺度的有序结构会产生更优异的整体协同性质,这对纳米/微米结构粒子的性能研究有重要意义。主要介绍了表面活性剂法、水热法和模板诱导法等。表面活性剂由于具有多种特殊、优异的性能,包覆在纳米粒子表面可使其组装成具有新颖结构的聚集体,是目前研究热点。水热法所得粒子具有纯度高、分散性好、晶形可控,生产成本低等特点已被广泛采用。     

Ultrasonic-template method synthesis of CdS hollow nanoparticle chains

A facile and efficient ultrasonic-template method has been developed for the fabrication of CdS hollow nanoparticle chains. The structures and morphologies of products were characterized by XRD and TEM. UV-Vis and photoluminescence (PL) spectra recorded the optical properties of CdS hollow nanoparticle chains, which showed obvious blue shift relative to the CdS bulk materials. Systematic studies found that the ultrasonic irradiation, concentration of template (polyacrylicamide) and injection method of reaction solution in the system were important factors on the controlled synthesis of hollow nanoparticle chains. The possible mechanism for the formation of CdS hollow nanoparticle chains was also discussed.     

Facile microwave-combustion synthesis of wurtzite CdS nanoparticles

In this study we first report microwave-combustion synthesis of faceted CdS nanoparticles by using cadmium thiocyanate complex as a single source precursor. This is the first example of a metal-thiocyanate (M-SCN) complex being used as a source for metal sulfides (M-S) preparation in a microwave-combustion process. The synthesized CdS was characterized using X-ray diffraction (XRD), field mission scanning electron microscopy (FE-SEM), and high-resolution transmission electron microscopy (HR-TEM). The by-product assisted combustion synthesis yields CdS nanoparticles with the mixtures of octahedral geometries, hexagonal, and triangle plate morphologies and the sizes were found to be 100 nm to 5 microm. The XRD patterns imply the formation of well crystallized wurtzite CdS. The influence of cadmium and sulfur precursors and microwave irradiation time on the morphology of CdS nanoparticle was also investigated. The cadmium and sulfur precursors strongly influenced the CdS morphology and increasing the microwave irradiation time and intensity has no effect on the CdS morphology. In addition, a plausible mechanism of CdS nanoparticle formation has been proposed in this research.     

Cadmium sulfide and cadmium selenide/cadmium sulfide nanoparticles stabilized in water with poly(cysteine acrylamide)

Cysteine acrylamide (N-acryloyl L-cysteine) stabilizes CdS nanoparticles as the particles form in aqueous dispersions. Cysteine acrylamide also exchanges for citrate on the surfaces of CdSe and core/shell CdSe/CdS nanoparticles to provide greater stability. Heating of the nanoparticle dispersions polymerizes the cysteine acrylamide on the surface to form a more efficient polydentate stabilizer. The polymer-coated nanoparticle dispersions are colloidally stable even after removal of low molecular weight solutes by dialysis. Emission quantum yields of the polymer-coated CdSe and CdSe/CdS samples were 0.9% and 2.6%, respectively, after aging of the samples in light. CdSe/CdS coated with poly(cysteine acrylamide) is colloidally stable for at least two years in the dark at 5 degrees C.     

Positionally defined, binary semiconductor nanoparticles synthesized by scanning probe block copolymer lithography

We report the first method for synthesizing binary semiconductor materials by scanning probe block copolymer lithography (SPBCL) in desired locations on a surface. In this work, we utilize SPBCL to create polymer features containing a desired amount of Cd(2+), which is defined by the feature volume. When they are subsequently reacted in H(2)S in the vapor phase, a single CdS nanoparticle is formed in each block copolymer (BCP) feature. The CdS nanoparticles were shown to be both crystalline and luminescent. Importantly, the CdS nanoparticle sizes can be tuned since their diameters depend on the volume of the originally deposited BCP feature.     

Formation of CdS nanoparticle necklaces with functionalized dendronized polymers

A one-dimensional assembly of cadmium sulfide (CdS) nanoparticles was prepared by using functionalized polymers with pendant Fréchet-type dendritic wedges of different generation. The novel dendronized polymers acted as both nanoreactors for the formation of CdS nanoparticles and a template to arrange the nanoparticles into a necklace. The polymers of different dendron generation were applied to stabilize CdS particles and the effect of dendron size was observed. CdS nanoparticle necklaces were obtained successfully when polymers bearing second-generation dendrons were applied.     

Hydrothermal synthesis of cdS nanoparticle-decorated TiO2 nanobelts for solar cell

We fabricated a solar cell using a hybrid film consisting of CdS nanoparticle-decorated TiO2 nanobelts, which were synthesized via a modified alkaline hydrothermal method. The hybrid film is flexible and contains homogeneous CdS nanoparticle light absorbers. Furthermore, the type II heterostructure of CdS/TiO2 facilitates charge separation in the CdS nanoparticle-decorated TiO2 nanobelts. The solar cell demonstrated a light-electricity power conversion efficiency of 2.52%. Next, we deposited the CdS nanoparticle-decorated TiO2 nanobelts onto a ZnO nanowire array forming an antireflective hybrid structure. The power conversion efficiency of the cell with the hybrid photoanode reached 2.84%.     

A photochemical method for controlling the size of CdS nanoparticles

The optical and electrical properties of semiconductor nanoparticles are strongly dependent on their size. A flexible control of the size of the nanoparticles is of interest for tuning their properties for different applications. Here we use a coupled method to control the size of CdS nanoparticles. The method involves the photochemical growth of CdS nanoparticles together with the use of a capping agent as an inhibiting factor. CdS nanoparticles were formed through a photoinduced reaction of CdSO(4) and Na(2)S(2)O(3) in an aqueous solution. Mercaptoethanol (C(2)H(6)OS) was used as the capping agent, and we investigated the effect of illumination time, illumination intensity and the concentration of capping agent on the nanoparticle size. Transmission electron microscopy (TEM) shows crystalline nanoparticles with relatively low dispersion. Optical absorption spectroscopy was mainly used to measure the band gap and size of the nanoparticles. Increasing the illumination time or illumination intensity increases the nanoparticle size, while higher capping agent concentration leads to smaller nanoparticle size. A band gap range of 2.75-3.4?eV was possible with our experimental conditions, corresponding to a 3.2-6.0?nm size range.     

Single w/o microemulsion templating of CdS nanoparticles

We report the synthesis of monodispersed CdS nanoparticle with tunable size by controlling the reaction aging time in a single water in oil (w/o) microemulsion system. The w/o microemulsion system consists of nonionic surfactant poly (oxyethylene)₅ nonyl phenol ether (NP5), poly (oxyethylene)₁₀ nonyl phenol ether (NP10), cyclohexane and aqueous solution (cadmium salt and thioacetamide). Thioacetamide (TAA) has been utilized as a source for slow release of sulfur ions in the in situ synthesis of CdS. UV-Visible spectra shows obvious blue shift for the CdS nanoparticles as compared to the bulk material due to quantum size effect. CdS nanoparticle size depends on the reaction aging time where longer reaction aging time yields bigger particles. CdS nanoparticles growth behaviour as a function of reaction aging time in the microemulsion system was characterized by UV-Visible spectroscopy. The particle growth follows a power law with an exponential in the order of 0.17. Energy Filter Transmissions Electron Microscopy (EFTEM) reveals monodispersed CdS nanoparticles with standard deviation, less than 8%.     

Size-controlled one-pot synthesis of fluorescent cadmium sulfide semiconductor nanoparticles in an apoferritin cavity

A simple size-controlled synthesis of cadmium sulfide (CdS) nanoparticle (NP) cores in the cavity of apoferritin from horse spleen (HsAFr) was performed by a slow chemical reaction synthesis and a two-step synthesis protocol. We found that the CdS NP core synthesis was slow and that premature CdS NP cores were formed in the apoferritin cavity when the concentration of ammonia water was low. It was proven that the control of the ammonia water concentration can govern the CdS NP core synthesis and successfully produce size-controlled CdS NP cores with diameters from 4.7 to 7.1?nm with narrow size dispersion. X-ray powder diffraction (XRD), energy dispersive spectroscopy (EDS) analysis and high-resolution transmission electron microscopy (HR-TEM) observation characterized the CdS NP cores obtained as cubic polycrystalline NPs, which showed photoluminescence with red shifts depending on their diameters. From the research of CdS NP core synthesis in the recombinant apoferritins, the zeta potential of apoferritin is important for the biomineralization of CdS NP cores in the apoferritin cavity. These synthesized CdS NPs with different photoluminescence properties will be applicable in a wide variety of nano-applications.     

Effect of CdS nanoparticles on the properties of a protein matrix

The effect of CdS nanoparticles on the properties of a protein matrix, R-phycoerythrin, has been studied using absorption and fluorescence spectroscopy techniques, atomic force microscopy, confocal fluorescence microscopy, and analytical ultracentrifugation. The results demonstrate that CdS nanoparticles distort the native state of R-phycoerythrin, as evidenced by the reduction in absorption, partial fluorescence quenching, the reduction in fluorescence lifetime from 2.9 to 1.9 ns in solution and the increase to 3.3 ns upon adsorption on glass, and the influence of CdS nanoparticles on the sedimentation coefficient distribution of R-phycoerythrin. We conclude that a CdS nanoparticle synthesized inside an R-phycoerythrin molecule influences the chromophore—chromophore interaction and stabilizes the hexamer form of the protein.