固相法合成纳米硫化镉研究进展

纳米硫化镉以其独特的光电性能，在光致发光、电致发光、传感器、红外窗口材料、光催化等许多领域有着广泛的应用，其合成方法受到人们的广泛关注。综述了我国近年来用固相法合成CdS纳米材料的研究现状，指出各种制备方法的优缺点，并展望其未来发展。     

硫化镉纳米粒子的合成与应用

研究了用硫脲分子进行表面化学修饰的CdS纳米粒子的合成方法，并引入了一些表面活性剂作为平衡反离子，进一步对CdS表面作了修饰，增加了CdS纳米离子在有机溶剂中的稳定性和可分散性，我们还探讨了温度，浓度，pH等因素对合成的影响，并通过紫外一可见吸收光谱等手段进行了表征，所得微粒呈球形，硫脲分子与CdS纳米粒子富Cd^2 表面通过形成Cd-S配位键而修饰在粒子表面，这种表面修饰的CdS纳米材料在非线性光学及自组装方面具有优异的性能，还研究了含纳米硫化镉的有机／无机杂化非线性光学薄膜材料的制备。     

纳米硫化镉的合成及其电化学催化性能测试

以3CdSO<,4>·8H<,2>O、Na<,2>S·9H<,2>O和EDTA为主要原料,在室温下,利用液相沉淀法制备CdS纳米晶.利用X射线粉末衍射(XRD)技术对产物进行表征,并用电化学分析仪测试产物对硫化物电解质溶液的催化性能.对产物的形成机理进行了初步分析.结果表明,产物纳米CdS为立方晶相,纯度较高.产物对1...     

新型纳米材料的合成及应用

本文简要介绍了纳米材料的定义、产生、发展及应用;重点介绍了:(1)新型纳米材料的合成及在医药学中的应用;(2)新型纳米材料的合成及在材料科学中的应用;(3)新型纳米材料的合成及在催化科学中的应用。并对纳米材料的发展进行了展望。     

一维纳米材料的合成与应用

一维纳米材料是物质在纳米尺度上的一种特殊结构,具有广阔的潜在应用前景,如高密度存储记忆元件、超微型纳米阵列激光器、新型电子器件等;合成出的一维纳米材料对基础研究和应用研究具有重要意义;本文综述了一维纳米材料的合成方法以及其在能量转化、激光器和传感器等方面的应用研究情况.     

溶剂热法合成硫化镉微晶工艺研究

以氯化镉为前驱体,硫化钠、硫代乙酰胺、硫脲等为硫源,乙二醇、乙醇等为溶剂,通过溶剂热法制备硫化镉微晶.设计L9(34)正交试验,探讨了反应温度、反应时间等对硫化镉微晶大小和形貌的影响.所得产物经离心、洗涤、干燥后,用纳米粒度仪分别测定各产物的平均粒径,同时用扫描电子显微镜测定部分产物的大小和形貌,并用极差分析法找寻最佳合成工艺.结果表明:以硫代乙酰胺为硫源,乙二醇为溶剂,反应温度为100℃,反应时间为10 h,可得到直径为0.5～0.7μm的片状硫化镉晶体.该方法工艺简单,反应条件温和,制备的硫化镉晶体大小分布均匀,形貌单一.     

微波在合成纳米材料中的应用

阐述了微波在合成粉体,半导体,分子膜和载体等纳米材料的一些重要应用.     

纳米材料自组装合成技术研究进展

简要介绍了制备纳米材料的自组装技术的基本原理，概述了自组装合成方法，并对3种典型的自组装法的特点和研究现状进行了评述。     

CdS纳米管合成方法研究进展

作为一种典型的光电半导体材料,硫化镉(CdS)一维纳米材料的合成近年来受到人们的广泛关注.本文综述了阳极氧化铝(AAO)、聚四氟乙烯(PTFE)硬模板,聚乙烯醇(PVA)软模板和超声化学法合成一维CdS纳米管,介绍了各种合成方法中CdS纳米管的形成机制.     

One-Pot Synthesis of Biocompatible CdSe/CdS Quantum Dots and Their Applications as Fluorescent Biological Labels

We developed a novel one-pot polyol approach for the synthesis of biocompatible CdSe quantum dots (QDs) using poly(acrylic acid) (PAA) as a capping ligand at 240°C. The morphological and structural characterization confirmed the formation of biocompatible and monodisperse CdSe QDs with several nanometers in size. The encapsulation of CdS thin layers on the surface of CdSe QDs (CdSe/CdS core–shell QDs) was used for passivating the defect emission (650 nm) and enhancing the fluorescent quantum yields up to 30% of band-to-band emission (530–600 nm). Moreover, the PL emission peak of CdSe/CdS core–shell QDs could be tuned from 530 to 600 nm by the size of CdSe core. The as-prepared CdSe/CdS core–shell QDs with small size, well water solubility, good monodispersity, and bright PL emission showed high performance as fluorescent cell labels in vitro. The viability of QDs-labeled 293T cells was evaluated using a 3-(4,5-dimethylthiazol)-2-diphenyltertrazolium bromide (MTT) assay. The results showed the satisfactory (>80%) biocompatibility of as-synthesized PAA-capped QDs at the Cd concentration of 15 μg/ml.     

纳米氧化镁合成方法研究进展

目前合成纳米氧化镁的方法,主要包括固相法和液相法.液相法有直接沉淀法、均匀沉淀法、溶胶-凝胶法等.分别评述了这些方法的优点和不足,展望未来纳米氧化镁合成的发展方向.     

Ordered Mesostructured CdS Nanowire Arrays with Rectifying Properties

Highly ordered mesoporous CdS nanowire arrays were synthesized by using mesoporous silica as hard template and cadmium xanthate (CdR₂) as a single precursor. Upon etching silica, mesoporous CdS nanowire arrays were produced with a yield as high as 93 wt%. The nanowire arrays were characterized by XRD, N₂ adsorption, TEM, and SEM. The results show that the CdS products replicated from the mesoporous silica SBA-15 hard template possess highly ordered hexagonal mesostructure and fiber-like morphology, analogous to the mother template. The current–voltage characteristics of CdS nanoarrays are strongly nonlinear and asymmetrical, showing rectifying diode-like behavior.     

Synthesis and potential applications of silicon carbide nanomaterials / nanocomposites

The rapid development of nanotechnologies has accelerated the research in silicon carbide (SiC) nanomaterial synthesis and application. SiC nanomaterials have unique chemical and physical properties, such as distinctive electronic and optical properties, good chemical resistance, high thermal stability, and low dimensionality. These properties lead to a wide range of applications. The progress in SiC nanomaterials in recent years is significant, but a review of the progress is lacking. This article is designed to fill the gap. The review first summarizes various methods for preparing different SiC nanomaterials/nanocomposites, including the carbothermal method, chemical vapor deposition method, and other synthesis techniques using unconventional energy sources such as microwave, plasma, solar energy, and neutron irradiation. Discussion is then made on the significant applications of the SiC nanomaterials/nanocomposites, especially in sensors, catalyst supports, energy storage materials, structural reinforcement, and semiconductor materials. Finally, the conclusion of this review is made with the possible future development trends.     

Surfactant-assisted growth and characterization of CdS nanorods

Well-defined CdS nanorods were synthesized using hydrothermal process with ethylenediamine as a bidentate ligand to form Cd²⁺ complexes and polyoxyethylene 20 cetyl ether providing an effective control over the crystal uniformity of CdS nanorods. The photoluminescence (PL) spectrum of the nanorods indicated that they have potential applications in light-emission devices.     

高压固相法合成CdS纳米粒子及其表征

以固相合成法在不同的压力条件下利用温度控制,快速合成CdS纳米粒子.通过X射线粉末衍射、透射电镜和荧光光度计,对CdS纳米粒子的结构及光学性质进行了表征.利用XRD研究了同一添加剂下不同反应温度、不同压力对蚋米粒子足寸的影响,利用TEM表征了产物的形貌.结果表明,在添加剂丙三醇存在条件下,控制反应温度和压力对粒径均有一定的影响.     

Excitonic Transitions and Off-resonant Optical Limiting in CdS Quantum Dots Stabilized in a Synthetic Glue Matrix

Stable films containing CdS quantum dots of mean size 3.4 nm embedded in a solid host matrix are prepared using a room temperature chemical route of synthesis. CdS/synthetic glue nanocomposites are characterized using high resolution transmission electron microscopy, infrared spectroscopy, differential scanning calorimetry and thermogravimetric analysis. Significant blue shift from the bulk absorption edge is observed in optical absorption as well as photoacoustic spectra indicating strong quantum confinement. The exciton transitions are better resolved in photoacoustic spectroscopy compared to optical absorption spectroscopy. We assign the first four bands observed in photoacoustic spectroscopy to 1s _e –1s _h , 1p _e –1p _h , 1d _e –1d _h and 2p _e –2p _h transitions using a non interacting particle model. Nonlinear absorption studies are done using z-scan technique with nanosecond pulses in the off resonant regime. The origin of optical limiting is predominantly two photon absorption mechanism.     

Structural and optical studies of CdS and CdS:Ag nano needles prepared by a SILAR method

Nano-crystalline CdS and Ag-doped CdS films are deposited on glass substrate by a SILAR technique at room temperature with cationic precursors of cadmium nitrate and silver nitrate, and anionic precursor of sodium sulfide with different S:Cd ratio in starting solutions. In order to fabricate samples, substrates were taken in the solutions with determined duration and immersion cycles. To investigate the structural and morphological characteristics of the samples XRD analysis and SEM were used. The X-ray diffraction patterns show that the CdS samples have cubic crystal structure with preferential orientation along the (111) plane and CdS:Ag samples have hexagonal crystal structure with preferential orientation along the (002) plane. Also the peak intensity of XRD patterns of CdS increases with increasing the number of immersion cycles. Optical reflection of the layers is measured with a spectrophotometer and their optical absorption coefficient and band gaps are calculated. The band gap energy of Ag-doped samples decreases respect to CdS samples. It seems that silver doping creates intermediate levels in the energy gap and this causes decreasing of energy gap. Making samples with different S:Cd ratio demonstrates that the sample with 3:1 ratio has highest peak intensity in the XRD pattern and best stoichiometry. It is also observed that with increasing S:Cd ratio, the band gap energy of the samples decreases.     

The ion implantation-induced properties of one-dimensional nanomaterials

Nowadays, ion implantation is an extensively used technique for material modification. Using this method, we can tailor the properties of target materials, including morphological, mechanical, electronic, and optical properties. All of these modifications impel nanomaterials to be a more useful application to fabricate more high-performance nanomaterial-based devices. Ion implantation is an accurate and controlled doping method for one-dimensional nanomaterials. In this article, we review recent research on ion implantation-induced effects in one-dimensional nanostructure, such as nanowires, nanotubes, and nanobelts. In addition, the optical property of single cadmium sulfide nanobelt implanted by N⁺ ions has been researched.