微乳液中纳米ZnS、CdS微粒的合成与表征

以乙酸锌、硝酸镉和硫化钠为原料,室温下,采用微乳液法合成ZnS、CdS纳米粒子。利用rIEM、XRD、Raman、UV-Vis和PL等检测手段对产物进行表征。结果表明,合成的zns纳米晶粒径在25m左右,为立方β-Zns晶相;ω值对合成纳米cds的形貌和粒径产生重要影响,纳米Cds粒径为5nm左右,在紫外吸收光谱和荧光发射光谱上均表现出明显的特征,可作为荧光量子点使用。     

巯基乙酸修饰ZnS纳米颗粒的水相合成及表征

以巯基乙酸(HSCH2COOH, RSH)为表面修饰剂,采用水相合成法制备了表面修饰巯基乙酸的ZnS纳米颗粒. 采用透射电子显微镜、粒度分布、X射线衍射和红外光谱等对ZnS纳米颗粒进行了表征,并对ZnS纳米粒子的制备条件进行了详细的考察. 结果表明,水相合成法的最佳制备条件为：反应pH值8.0, Zn2+:S2-:RSH(摩尔浓度比)为1:1.34:2. 在最佳条件下可制备粒径小(11 nm)且粒度分布窄、分散性好的ZnS纳米粒子,其晶体属面心立方b-闪锌矿结构.     

纳米硫化锌的合成研究

利用化学沉淀法，均匀沉淀法，乳液法合成了不同晶粒尺寸的纳米ZnS，用X-射线衍射技术和透射电镜研究了材料的晶体结构和陶瓷微结构，并用TG－DTA测定了材料的热稳定性，探讨了不同实验方法对纳米颗粒晶粒度的影响，结果表明，610℃以前ZnS能在空气中稳定存在，乳液法能得到颗粒细小的ZnS，且具有生产成本低，产率高等特点。     

ZnS纳米粒子的微乳液合成研究

研究了电导率测定微乳液的最大增溶水量及微乳液制备硫化锌纳米粒子的过程。以Span80和Tween80为复配表面活性剂,正辛烷作为油相,在超声波作用下制备微乳液;利用电导率仪测定微乳液的电导率,利用Original lab绘图软件对得到的电导率作图,通过曲线的突变点来确定微乳液的最大增溶水量;通过讨论亲水亲油平衡值(HLB)对微乳液最大增溶水量的影响,得到了较佳的微乳液体系配比。以硫代已酰胺(TAA)和醋酸锌(Zn(Ac)2)作为反应物,在超声波的分散作用下制备ZnS纳米粒子。采用XRD及TEM对超细样品进行表征,得到的样品为β晶型ZnS,粒子粒径30 nm左右。此外,还探讨了反应温度对产品收率的影响以及干燥方法对粒子团聚的影响。     

超声功率对合成ZnS纳米晶的影响

以无水氯化锌、硫代乙酰胺等为起始原料,采用声化学法制备了硫化锌(ZnS)纳米晶。利用X射线衍射、透射电子显微镜对样品进行表征,研究了超声功率对合成产物的粒度及其反应速率的影响。结果表明:所制备ZnS纳米晶粒径在10nm左右,为α-ZnS纤锌矿结构,六方晶系,形貌为球形或近球形。随超声功率增强,ZnS纳米晶晶粒尺寸略有减小。反应时间小于110min时,随超声功率增加,产物的合成速率增大。此后,随着反应时间的延长,合成速率随超声功率的增大出现极值,当反应时间超过110min,反应速率在超声功率为300W处出现极大值。     

低温溶剂热法合成单分散氧化钛纳米棒

以Ti（OC4H8）4为无机前驱体、正辛酸为溶剂,在80-100℃一步合成了单分散的锐钛矿TiO2纳米棒状粉末。用X射线衍射、高分辨透射电子显微镜观察对样品进行了表征。结果表明：纳米棒状粉末具有窄的尺寸分布,直径为3～4nm,长度为10～20nm,长度方向为锐钛矿相C轴。此外,初步探讨了纳米棒的形成机理。     

非均相回流技术制备开口ZnS空心微球

以部分互溶的水-乙醚液液平衡系统为反应介质,硫代乙酰胺和醋酸锌分别为硫源和锌源,通过非均相回流技术成功制备了开口硫化锌空心微球,并对所得样品进行了性能表征.开口硫化锌空心微球形貌规整,直径约为8μm,开口圆孔直径约为1.6μm,纯度高,具有立方晶相结构.     

锌基硫化锌纳米棒阵列的溶剂热原位合成及其光学性质

利用金属锌片为锌源,采用溶剂热法在锌片表面生长出垂直于表面的直径约为200nm的硫化锌纳米棒阵列。利用X射线衍射(XRD)和扫描电镜(SEM)对不同反应时间制备的锌基硫化锌纳米结构进行表征发现,延长反应时间有助于得到均匀一致的定向生长的纳米棒阵列。利用漫反射紫外可见吸收光谱(UV/Visdiffuse-reflectance spectra)对锌基硫化锌纳米棒阵列在紫外可见光波段的光学吸收性能进行了研究,结果表明合成的结晶性良好的ZnS纳米棒阵列其带边吸收在347nm,对应的禁带宽度为3.47eV。提出了硫化锌纳米棒阵列在形成过程中的化学反应机理。     

聚苯乙烯纳米微球合成工艺研究

以苯乙烯(St)为单体,十二烷基硫酸钠为乳化剂、过硫酸钾为引发剂,碳酸氢钠和氢氧化钠为复合缓冲剂,通过乳液聚合反应,合成了粒径分布均匀的聚苯乙烯纳米微球(PSt)。在确定缓冲剂用量及引发剂滴加方式的条件下,经正交实验优选出最佳合成工艺条件如下:蒸馏水与苯乙烯的体积比为1.5:1、乳化剂用量为苯乙烯质量的1.0%、引发剂用量为苯乙烯质量的1.2%、反应时间为8h,反应温度为80℃。在此条件下转化率为94.58%,并用扫描电镜(SEM)和红外光谱(FTIR)对其进行了表征。     

Au-SiO2复合纳米微球的制备与表征

采用溶胶-凝胶法制备SiO2纳米微球,以KH-550为粘结剂,利用简单的化学还原法,成功制备出Au-SiO2复合纳米微球,并通过扫描电子显微镜,透射电子显微镜,X射线衍射仪,紫外-可见分光光度计和多功能成像光电子能谱仪对其进行表征.结果表明,Au-SiO2复合纳米微球粒径约130 ～ 160 nm,且颗粒较均匀、分散性较好.样品中金纳米粒子均匀分散于SiO2纳米微球表面,粒径约4～9 nm,具有良好的面心立方结构,晶型良好,且Au物种主要以零价金属态存在.     

纳米硫化锌的制备与应用研究现状

介绍了纳米硫化锌的制备方法,固相法、液相法、气相法,纳米硫化锌性能优越,用途广泛.     

苄青霉素低毒前体苯乙酰基乙醇胺的合成研究

以苯乙酸乙酯和乙醇胺为原料合成了苄青霉素低毒前体苯乙酰基乙醇胺。最佳合成条件为：ｎ（苯乙酸乙酯）ｎ（乙醇胺）＝ １∶１．０５;催化剂与苯乙酸的质量比为２ ％ ;反应温度为１３０℃;反应时间为３ｈ。产品收率为９７．４ ％ ,纯度≥９８％ 。     

前驱物法低温合成六方氮化硼

本文以三聚氰胺和硼酸为原料,先采用湿化学法合成棒状前驱物,然后将其在空气气氛中高温培烧制得六方氮化硼.实验考察了反应原料配比,反应物浓度,高温培烧的时间及温度对产物的影响.采用IR、化学分析、XRD、粒度分析和SEM等方法对前驱物及产物进行了表征,确定了前驱物及产物的组成、物相、粒度分布及形貌.研究结果表明:合成前驱物的适宜原料配比是C3N6H6∶H3BO3=1∶2,浓度为0.4 mol/L,合成的前驱物是分子式为C3N6H6·2H3BO3的棒状超分子加合物;在温度950℃,空气气氛中培烧6h能得到晶型良好、平均粒径为15 μm的六方氮化硼粉体.     

ZnS Semiconductive Powder Doped with Transition Metal Ions via Mechanochemical Synthesis Technique

The solid state synthesis can be carried out by using the initial pure metal zinc and inorganic sulfur powder mixtures by means of the mechanochemical synthesis route. The completion of solid state reaction between pure zinc and sulfur powder to produce c-ZnS and h-ZnS phases via such a route was rather fast, as compared to other non-sulfide systems by the similar method. The study was aimed to investigate the microstructure development and phase formation through the solid state reaction by controlling the processing parameters involved in this process including grinding media to powder weight ratio, solid state reaction duration, reaction atmosphere, stoichiometric ratio of zinc and sulfur elements, grinding media and choice of minor additives such as teflon-based polymeric lubricants and transition metal dopants (Mn, Cu). Both as-synthesized powders and heat-treated ZnS materials with various stoichiometric ratios were characterized by XRD, EXAFS and XANES analysis. The interesting results from X-ray absorption spectroscopy (XAS) would provide us some strong evidence whether stoichiometric and non-stoichiometric ZnS material can be successfully formed. The minor amount (0.5wt%)of Mn+2 or Cu+2 ion dopants added to the powder batch with the Zn/S stoichiometric ratio between1.00 to 1.05 was found to favor the reaction rate in the mechanochemical synthesis. Moreover, the obtained results of ZnS phase development under reaction conditions and different transition metal dopants in this study would imply that synthesis of other kind of sulfide compounds can be achieved using the demonstrated technique.     

A Versatile Route for the Synthesis of Nickel Oxide Nanostructures Without Organics at Low Temperature

Nickel oxide nanoparticles and nanoflowers have been synthesized by a soft reaction of nickel powder and water without organics at 100 °C. The mechanism for the formation of nanostructures is briefly described in accordance with decomposition of metal with water giving out hydrogen. The structure, morphology, and the crystalline phase of resulting nanostructures have been characterized by various techniques. Compared with other methods, the present method is simple, fast, economical, template-free, and without organics. In addition, the approach is nontoxic without producing hazardous waste and could be expanded to provide a general and convenient strategy for the synthesis of nanostructures to other functional nanomaterials.     

邻羟甲基苯甲酸内酯的一步合成

邻苯二甲酸酐与 Zn/ HCl作用 ,一步合成邻羟甲基苯甲酸内酯 ,操作简便 ,反应条件温和 ,原料价廉易得 ,收率 81 .7%。     

Synthesis and properties of ZnS/ polyimide nanocomposite films

A series of ZnS/polyimide (PI) nanocomposite films with different ZnS contents have been successfully fabricated by incorporating ZnS nanoparticles with a diameter of 2–5 nm into polyamic acid, followed by a stepwise thermal imidization process. X‐ray photoelectron spectroscopy results confirm the successful introduction of ZnS particles into PI matrix. Transmission electron microscopy images show that the ZnS nanoparticles were uniformly dispersed in the polymer matrix without aggregation. The incorporation of ZnS nanoparticles can improve the mechanical properties and the glass transition temperature of nanocomposites, while the thermal degradation temperature of nanocomposites decreases with increasing ZnS content. Copyright © 2006 Society of Chemical Industry Society of Chemical Industry     

Synthesis of mesoporous ZnS synergistically templated by butylamine and alkanols

Pore size and pore volume adjustable mesoporous ZnS was synthesized through a co-template method, which was achieved by the combined interaction between butylamine and some alkanols with proper lengths of the straight carbon chain. The pore size for mesoporous ZnS templated by butyl amine alone was 4.29 nm, and could be enlarged to 6.96 and 8.33 nm respectively through adding certain amounts of hexanol and octanol. Correspondingly, the pore volume also exhibited an augmentation with increasing carbon chain lengths of alkanols from C₆ to C₈. However, the pore size and pore volume dropped abruptly when decanol was added as the auxiliary agent. The formation of mesopores for ZnS prepared using butylamine molecules as the only templating agent is considered to be attributed to the coordination between N atoms in amines and Zn²⁺ ions at the surfaces of zinc suphide. The templating effect of butylamines might be improved by adding hexanols and octanols to form aggregates through solubilization to tailor the pore size and pore volume of ZnS effectively, while the function of decanols for changing the porous structure is restricted by its low solubility.