稀土掺杂ZnS纳米晶中稀土离子与纳米基质之间的能量传递

以甲基丙烯酸为表面包覆剂在水／醇溶液中合成了ZnS:Eu^3 ,ZnS:Tb^3 纳米晶,用傅里叶变换红外光谱和X射线粉末衍射谱表征了样品的表面与晶型,样品均为立方闪锌矿型,没有出现与稀土离子相关的相;用光致发光和激发谱研究了样品中的发光过程,其中ZnS:Tb^3 纳米晶中存在纳米基质与Tb^3 之间的能量传递,并引起Tb^3 的特征发射。     

乳状液法制备ZnS纳米粒子

乳状液法制备ＺｎＳ纳米粒子黄宵滨马季铭＊程虎民赵振国齐利民（北京大学化学系北京１００８７１）关键词硫化锌，纳米粒子，乳状液，混合乳化剂１９９６－０５－２０收稿，１９９６－０９－０４修回国家自然科学基金资助项目近年来，利用反胶束或Ｗ／Ｏ微乳制备超细粒子...     

基于ZnS纳米粒子的有机凝胶荧光薄膜的制备及其传感性能

本文首先采用油水界面法制备发光纳米ZnS粒子,再通过物理混合法,将其分散在溶有小分子胶凝剂的有机溶液中,流延于玻璃基质表面,得到ZnS荧光薄膜。实验结果表明,ZnS纳米粒子的平均粒径大小约为200 nm,具有立方晶型结构,并且在杂化薄膜中具有良好的分散性;胶凝剂形成的网络结构对ZnS纳米粒子具有良好的限域效应,表现为稳定的发光性能;气敏实验表明,该杂化膜对挥发性有机单胺和二胺具有灵敏的选择性传感作用;且其灵敏度随着杂化薄膜中ZnS担载量的增大逐渐提高;可逆性实验表明该薄膜对乙二胺蒸汽具有良好的可逆响应性。     

纳米超粒子的水相制备及生物医学应用

纳米超粒子(Supraparticles, SPs)是指由一种或多种纳米颗粒组装单元,在内、外部驱动力的作用下,自组装形成的具有一定形貌、尺寸和分级结构的纳米实体.由于具有复杂的拓扑结构、丰富的表面可修饰性、可调的集合性质和协同效应, SPs在生物医学等领域具有较大的应用潜力.本文总结了近几年来水相制备SPs的研究进展,包括组装单元之间作用力调制、 SPs的物理、化学性质及其在生物成像、疾病诊疗等方面的应用,最后讨论了SPs结构和性能的精准调控、生物医学应用中存在的主要问题以及未来SPs的发展方向.     

纳米粒子及其材料的特性、应用和制备

本文介绍了纳米粒子的一般概念、特性及本质根源。纳米粒子因其特异的性能在高科技领域得到了日益广泛的应用。文中对纳米材料现有的应用及其前景作了简要的介绍，并综合评述了目前国内外制备纳米粒子的常用方法，综述了引起粒子间团聚的机理和后处理过程中有效地防止团聚的方法。     

ZnS纳米粒子的固相合成及其光学性能

将不同的添加剂引入到低温固相反应中，快速合成了不同尺寸的ZnS纳米粒子。利用TEM表征了产物形貌，利用XRD研究了不同的添加剂、同一添加剂下不同的反应温度、不同反应时间对纳米粒子尺寸的影响。结果表明，不同的添加剂对粒子的尺寸影响较大，其中，十二烷基胺以其特殊的反应方式在较高温度下获得了较小的纳米粒子。另外，在PEG400存在条件下，反应温度和反应时间对粒子尺寸均有一定的影响。同时，对不同条件下所得产物的紫外-可见光吸收性能也进行了测试。     

高性能磁性纳米粒子的有机相制备与生物应用的研究进展

磁性纳米粒子(MNPs)的合成开发在基础科学研究和技术应用方面得到了深入的发展。与大块的磁性材料不同,MNPs展现出了独特的磁性,并且可以通过系统的纳米尺寸工程调控它们的性能。本文首先简要介绍了MNPs的基本特征,总结了不同MNPs的制备方法,包括金属、合金、金属氧化物和多功能的MNPs;重点关注了可精确控制MNPs尺寸、形状、组成和结构的有机相合成方法;最后讨论了这些MNPs在生物方面的应用。     

硫化锌纳米粒子的乳液合成

纳米材料被人们认为是新型的功能材料^[1]。作为过渡金属硫化物,硫化锌（ZnS)材料显示出许多特异光电性能,在许多领域有着广泛的应用^[2],因而一直被应用和研究。     

Cr掺杂镓铟酸锌长余辉纳米粒子的制备及生物传感应用

通过水热法合成了不同含量In离子掺杂的ZnGa_1.99-xIn_xO₄∶Cr_{0. 01}³⁺长余辉纳米粒子(PLNPs)。通过In掺杂和改变反应pH条件,PLNPs的余辉强度和时长明显改善,近红外余辉时间超过96h,平均粒径为15.36nm。实验结果表明,PLNPs的余辉强度被多巴胺猝灭,PLNPs的相对余辉强度(F₀-F)/F₀与多巴胺浓度在0.005～20μmol/L范围内呈良好的线性关系,线性回归线方程为y=0.1789x+0.4427,相关系数R²=0.9974,对多巴胺的检出限为0.0024μmol/L,其在生物传感领域有应用潜力。     

氮掺杂碳纳米粒子的制备及在游离氯检测中的应用

以蔗糖和尿素为前驱体,在油酸介质中通过溶剂热法一步合成了氮掺杂碳纳米粒子,量子产率为15.1％.基于次氯酸对氮掺杂碳纳米粒子的快速、高选择性猝灭,建立了定量测定水中游离氯含量的新方法.次氯酸浓度在0.05～25.00 μmol/L范围内与氮掺杂碳纳米粒子的荧光猝灭率呈良好的线性关系,检出限(S/N=3)为23 nmol/L.本方法可应用于实际水样中游离氯含量的测定.     

Spectro-Optical and Photochemical Properties of ZnS Nanoparticles

The spectro-optical properties of nanoparticles of ZnS have been studied and the structure of the long wavelength edge of the absorption bands of the semiconductor has been analyzed. The influence of the synthesis conditions on the size and optical properties of the nanoparticles of ZnS formed has been investigated. It has been established that oxidative photo-corrosion of zinc sulfide colloids is accompanied by a decrease in the average size of ZnS nanoparticles and an increase in the defectiveness of their surfaces.__________Translated from Teoreticheskaya i Eksperimental’naya Khimiya, Vol. 41, No. 2, pp. 105–109, March–April, 2005.     

La掺杂ZnS量子点的制备及其表征

ZnS量子点的发光强度较弱,用水相合成技术掺杂一定浓度的La3+可以增强其发光性能。本文以实验用N-乙酰-L-半胱氨酸作保护剂,Zn(Ac)2作锌源,Na2S作硫源、La(Ac)3作镧源合成La掺杂的ZnS量子点,并通过透射电镜(TEM)和X-射线粉末衍射(XRD)对其物相进行了表征。紫外-可见(UV-Vis)及荧光(PL)光谱性质亦进行了表征。     

ZnS量子点的合成及荧光特性

采用液相沉淀法,用不同的硫源或金属离子螯合剂,从三个途径合成了不同粒径的ZnS量子点,并用透射电子显微镜,X-射线粉末衍射仪所合成的量子点进行了表征,用荧光分光光度计研究了量子点的荧光性质。结果表明,所合成的ZnS量子点为分散性好、纯度高且具有良好荧光特性的球形微粒。     

Luminescence of Polyethylene Glycol Coated CdSeTe/ZnS and InP/ZnS Nanoparticles in the Presence of Copper Cations

The use of click chemistry for quantum dot (QD) functionalization could be very promising for the development of bioconjugates dedicated to in vivo applications. Alkyne–azide ligation usually requires copper(I) catalysis. The luminescence response of CdSeTe/ZnS nanoparticles coated with polyethylene glycol (PEG) is studied in the presence of copper cations, and compared to that of InP/ZnS QDs coated with mercaptoundecanoic acid (MUA). The quenching mechanisms appear different. Luminescence quenching occurs without any wavelength shift in the absorption and emission spectra for the CdSeTe/ZnS/PEG nanocrystals. In this case, the presence of copper in the ZnS shell is evidenced by energy‐filtered transmission electron microscopy (EF‐TEM). By contrast, in the case of InP/ZnS/MUA nanocrystals, a redshift of the excitation and emission spectra, accompanied by an increase in absorbance and a decrease in photoluminescence, is observed. For CdSeTe/ZnS/PEG nanocrystals, PL quenching is enhanced for QDs with 1) smaller inorganic‐core diameter, 2) thinner PEG shell, and 3) hydroxyl terminal groups. Whereas copper‐induced PL quenching can be interesting for the design of sensitive cation sensors, copper‐free click reactions should be used for the efficient functionalization of nanocrystals dedicated to bioapplications, in order to achieve highly luminescent QD bioconjugates.     

亲油性ZnS纳米微粒的合成

纳米微粒具有小尺寸效应、表面效应、量子效应和宏观量子隧道效应等一系列普通材料所不具备的特性 ,因而引起科技工作者的广泛重视 ,成为材料科学研究的热点 .制备纳米微粒的方法很多 [1～ 7] ,但由于纳米微粒的小尺寸效应及表面效应 ,通常制备的无机纳米微粒极易团聚 ,而且无机纳米微粒的非油溶性使其在摩擦学领域的应用受到很大限制 .本文采用表面修饰 [8～ 11] 方法 ,通过共沉淀的竞争反应 ,制备了表面为有机修饰剂双十六烷基二硫代磷酸 (DDP)修饰的无机 Zn S纳米微粒 ,并用红外光谱、 X射线光电子能谱和透射电子显微镜等分析手段对表…     

Synthesis of Multifunctional Mn‐Doped CdTe/ZnS Core/Shell Quantum Dots

The synthesis of a novel water‐soluble Mn‐doped CdTe/ZnS core‐shell quantum dots using a proposed ultrasonic assistant method and 3‐mercaptopropionic acid (MPA) as stabilizer is descried. To obtain a high luminescent intensity, post‐preparative treatments, including the pH value, reaction temperature, reflux time and atmosphere, have been investigated. For an excellent fluorescence of Mn‐doped CdTe/ZnS, the optimal conditions were pH 11, reflux temperature 100°C and reflux time 3 h under N₂ atmosphere. While for phosphorescent Mn‐doped CdTe/ZnS QDs, the synthesis at pH 11, reflux temperature 100°C and reflux time 3 h under air atmosphere gave the best strong phosphorescence. The characterizations of Mn‐doped CdTe/ZnS QDs were also identified using AFM, IR, powder XRD and thermogravimetric analysis. The data indicated that the photochemical stability and the photoluminescence of CdTe QDs are greatly enhanced by the outer inorganic ZnS shell, and the doping Mn²⁺ ions in the as‐prepared quantum dots contribute to strong luminescence. The strong luminescence of Mn‐doped CdTe/ZnS QDs reflected that Mn ions act as recombination centers for the excited electron‐hole pairs, attributing to the transition from the triplet state (⁴T₁) to the ground state (⁶A₁) of the Mn²⁺ ions. All the experiments demonstrated that the surface states played important roles in the optical properties of Mn‐doped CdTe/ZnS core‐shell quantum dots.     

Photocatalytic Reduction of Zn(II) with Participation of ZnS Nanoparticles

We have studied the photochemical processes occurring in colloidal ZnS solutions containing zinc chloride and sodium sulfite as additives. Irradiation of such systems leads to reduction of Zn(II), the rate of which increases as the size of the ZnS nanoparticles decreases. Based on analysis of the kinetic curves for the reaction, we hypothesize that photoreduction of Zn(II) is a two-electron process. __________ Translated from Teoreticheskaya i Eksperimental'naya Khimiya, Vol. 41, No. 4, pp. 231–235, July–August, 2005.