溶胶模板法合成CdS纳米棒

以硝酸镉与硫代乙酰胺为起始物,采用DMF为溶剂,在低温(～50℃)下通过软化学法合成了CdS纳米棒,其直径为7～20nm,长度达500nm.通过XRD、TEM、SAED以及EDS对纳米棒的结构和成分进行了表征;通过引入乙酰丙酮(AcAc)控制钛酸丁酯水解,形成的溶胶中分子间网络孔道为CdS纳米棒提供了有效的生长模板.     

可控壳厚纳米CeO2中空球的制备、表征及其催化氧化性能

以聚苯乙烯微球为模板制备PS/CeO_2复合颗粒,再通过煅烧去除PS内核形成CeO_2纳米中空球,并通过控制反应液中硝酸铈的浓度来最终控制中空球的壳厚。用TEM、FESEM、SAED、FTIR、DLS等手段,对所制备样品的物相结构、形貌和粒径分布进行了表征。结果表明,CeO_2中空球内径约为200 nm,外径约为230-260 nm,壳厚分别约为15、20、25和30 nm,中空球壳层由大量粒径为5-10 nm的纳米CeO_2颗粒紧密堆积所组成。经CeO_2中空球催化臭氧氧化处理2 h后,对苯酚的降解率可达95%以上。     

聚电解质复合膜中原位合成纳米结构氧化铁中空微球并用于释氧光阳极(英文)

利用层层静电自组装技术,将PSS-Fe3+复合物与聚二烯丙基二甲基氯化铵(PDADMAC,Po-ly(diallyldimethylammonium)Chloride)交替吸附在三聚氰胺甲醛树脂(MF)微球外.以聚电解质复合层作为纳米反应器,原位合成了氧化铁纳米颗粒;高温热处理可将中心的MF微球去除,生成中空纳米结构的铁氧化物微球.TEM说明,中空微球具有单分散性;XRD说明纳米颗粒是α-Fe2O3,壁的孔径约为7nm.在紫外灯开启和关闭时,由该氧化铁微球修饰的释氧光阳极会引起光电流的即时变化,显示该中空α-Fe2O3微球组成的薄膜具有灵敏的光电催化活性.     

ZnO纳米球的微波水热合成及纯丙乳液改性研究

以六水合硝酸锌和三乙醇胺为原料,采用微波水热法快速合成出形貌规则的ZnO纳米球。利用XRD、SEM、TEM等分析手段对样品进行表征。结果表明ZnO纳米球直径约150nm且单分散性良好;TEM分析显示ZnO纳米球是由10～20nm的晶粒堆积而成的疏松球形结构;在较大的水热温度和水热时间范围内,所得产物均为100～200nm的颗粒。将ZnO纳米粒子改性后掺入到纯丙乳液中形成复合乳液,其涂膜的抗张强度和断裂伸长率均有较大提高,涂膜浸泡48h后的吸水率也降低约10%。     

单齿络合剂辅助水热合成CdS纳米棒

以单齿络合剂甲胺为辅助通过水热法制备了CdS纳米棒,所得CdS纳米棒分别用TEM、XRD、Raman和PL等技术进行了表征.研究了络合剂甲胺的浓度对CdS纳米晶体形貌的影响.实验发现当络合剂甲胺的浓度为1、5和20wt％时,水热合成CdS纳米晶体的形貌分别为纳米颗粒、短纳米棒和长纳米棒.这也表明络合剂的类型即单齿或双齿络合剂并不是水热合成CdS纳米棒形成的关键因素.基于实验结果,提出了一个可能的水热合成CdS纳米棒的形成机制:络合物结构—控制机理.     

中空CdS核壳材料在可见光下催化处理印染废水的探究

采用水浴法以醋酸镉、硫代乙酰胺为前驱体,聚苯乙烯微球为模版合成PS@CdS核壳复合材料,高温煅烧后得到中空的CdS核壳材料。利用SEM、TEM、XRD和FT-IR等测试手段对样品的形貌、成分、微观结构和粒度等进行了表征。结果表明:水浴法制备的CdS纳米材料具有空心结构,颗粒均匀呈杨梅状,壳层厚度约90~95nm,在可见光下具有良好的催化效能。     

表面活性剂对超细BaTiO3纳米颗粒制备的影响

以钛酸四丁酯为钛源,醋酸钡为钡源,采用改进的水热法(即溶剂热法)在低温条件下合成钙钛矿结构的超细钛酸钡纳米颗粒,重点研究表面活性剂对产物的影响,探讨了不同表面活性剂影响产物形貌和种类的作用机理.通过扫描电子显微镜(SEM)、X射线衍射(XRD)及能谱(EDS)对产物进行表征,结果表明加入不同的表面活性剂时,制备的产物不同,其产物的形貌分别为超细纳米线、纳米棒(直径约几十纳米)和纳米颗粒(尺寸约50～100nm).通过调节反应过程中的表面活性剂,可以实现从线状钡的硫酸盐到纯相的超细钛酸钡纳米颗粒的转变.此方法为尺寸小于20nm的钛酸钡颗粒的制备及铁电材料尺寸限制效应的研究提供了重要参考.     

单分散PSMMA@ZrO2核壳胶体颗粒及ZrO2中空颗粒的制备与表征

采用乙腈与乙醇混合溶剂法制备出单分散的PSMMA@ZrO2核壳胶体颗粒,并通过TEM、SEM等表征手段对乙腈相对含量以及催化剂选择等参数的影响进行研究,结果表明室温下乙腈相对体积含量为20%时,采用去离子水为催化剂可制得高质量的单分散核壳胶体颗粒.通过高温煅烧得到ZrO2中空球,XRD结果表明二氧化锆转化为单斜相.漫反射光谱结果表明ZrO2核壳颗粒与中空颗粒在测量光谱区间内均具有较高的反射率.     

精细结构SnO2纳米球的制备与表征

以SnCl4·5H2O为主要原料,用溶剂热技术在油酸体系中成功地合成了具有精细结构的SnO2纳米球.X射线衍射(XRD)和选区电子衍射(SAED)结果表明,制备出的SnO2微晶具有良好的结晶性;透射电镜(TEM)结果表明,得到的产物中含有尺寸约为50-80nm的SnO2纳米球,放大的17EM照片进一步揭示了此纳米球含有粒度为2-6nm超细粒子的精细结构.这种结构趋向于高的比表面积,适合于气敏探测器方面的应用.     

纳米CdS的配位沉淀合成及酒敏性能研究

用配位沉淀法在柠檬酸体系中合成了纳米CdS,用X-射线衍射（XRD）对产物进行物相分析,结果表明产物为立方闪锌矿结构,其粒径为25nm左右。将样品制成旁热式气敏元件进行测试,结果表明以CdS为基体的气敏元件在230℃时对0．005vol％乙醇气体的灵敏度高达45,对汽油、甲醇、丙酮等气体具有较好的选择性。     

水热微乳液法制备锂离子阳极材料CoS2纳米空心球

通过自制的纳米苯丙乳液粒子为吸附载体,以CoCl·6H2O和CS2为原料,在100℃水热条件下,于微乳液粒子表面反应6h制备出了CoS2空心纳米球.利用X射线粉末衍射仪(XRD)、透射电子显微镜(TEM)和扫描电子显微镜(SEM)对产物进行了表征.结果表明,所得产物为纯相的立方晶系CoS2空心纳米球,直径约120nm....     

Strong yellow emission of ZnO hollow nanospheres fabricated using polystyrene spheres as templates

ZnO hollow nanospheres were fabricated using polystyrene (PS) microspheres as templates were demonstrated in this paper. The structures and morphologies of obtained products were characterized by XRD, FESEM and TEM. The results revealed that ZnO hollow nanospheres possess a hexagonal wurtzite structure with a diameter around 450–500 nm. Ultraviolet–visible (UV–vis) analysis showed that ZnO hollow nanospheres had high absorption in the ultraviolet region and low absorption in the visible region. Room temperature photoluminescence (PL) spectrum showed a weak UV emission at 380 nm and a strong and broad yellow emission centered at 550 nm. The formation mechanism of hollow structure was also investigated.     

Simple solution approach to hollow nanospheres of cubic HgS

Hollow nanospheres of cubic HgS were fabricated via a simple solution approach. The composite, polymorph, and morphology of as-prepared HgS sample were characterized using XPS, XRD, and TEM. TEM analysis revealed that the hollow nanospheres were relatively uniform, with external diameters of ca. 160–400 nm. TEM analysis at relatively higher resolution revealed that the hollow spheres consisted of small nanoparticles. Based on the experimental results, possible formation mechanism was proposed.     

Preparation and characterization of hollow carbon nanospheres supported metallic catalysts by using one-step pyrolysis method

A versatile one-step pyrolysis method is successfully employed to fabricate hollow carbon nanospheres (HCNs, ca. 60 nm in diameter) supported with metallic nanoparticle catalyst. The resultant catalyst hybrid was characterized by using TEM, FTIR, TGA measurements. It is confirmed that, as the carbon precursor and hollow core/shell structure template, hollow chitosan nanospheres provide the important adsorption sites for the metallic precursor. The one-step pyrolysis process at 750 degrees C under nitrogen atmosphere results in the simultaneous decomposition of the chitosan nanospheres to HCNs and the adsorbed metal salt complex to metallic nanoparticles. It is found that metallic nanoparticles with an average diameter of ca. 4 nm highly dispersed in the carbon shell of HCNs, and no aggregation phenomenon occurs under the high deposition temperature. As a demonstration, the HCNs-supported Pt catalyst for the electrochemical methanol oxidation was studied.     

Fabrication and characterization of Ag-SiO2 composite hollow nanospheres

Ag-SiO₂ composite hollow nanospheres were synthesized by impregnation of hollow silica nanospheres (HSNSs), which were prepared by templating CaCO₃ nanoparticles, in [Ag(NH₃)₂]NO₃ aqueous solution followed by heat treatment. The straightforward process generates composite materials containing Ag nanoparticles, with the average size of 6–10 nm in diameter, uniformly dispersed and mainly distributed on the shells or between the spaces of the HSNSs. The Ag-supported HSNSs were characterized through TEM, EDS, and XPS. Furthermore, ASS, XRD and UV-Vis analyses demonstrated that higher loading efficiency could be achieved under the optimum loading conditions of a silver precursor solution of 0.08 M, pH = 9.0 and HSNSs with a BET surface area of 830.4 m²/g.     

Preparation of hollow CdSe nanospheres

Cadmium selenide (CdSe) hollow nanospheres (approximately 40–50 nm) have been successfully synthesized by γ-irradiating polyacrylamide (PAM) hydrogel template which contains CdCl₂ and Na₂SeO₃ aqueous solution at room temperature. The nanospheres were characterized by energy dispersive spectrum (EDS), field emission scanning electron micrograph (FESEM), transmission electron microscopy (TEM) and high-resolution transmission electron micrograph (HRTEM), respectively. EDS showed that nanospheres were composed of Cd and Se (atomic ratio, 1.15:1). A possible formation mechanism of CdSe hollow nanospheres through two-steps was presented.     

High-yield room temperature route to copper sulfide hollow nanospheres and their electrochemical properties

CuS hollow nanospheres have been successfully synthesized in high yield by reacting anhydrous cupric sulfate (CuSO(4)·5H(2)O) with thioacetamide (TAA) in ethylene glycol (EG) with the assistance of cetyltrimethylammonium bromide (CTAB). The products were characterized systematically by XRD, EDX, FESEM, TEM and BET measurement and size analysis, CV, LSV and CP. FESEM and TEM images revealed that the as-prepared CuS hollow nanospheres had a mean diameter of about 500 nm with a hollow cavity of about 340 nm and shell thickness of about 80 nm. The spheres were constructed by numerous nanoflakes. The Brunauer-Emmett-Teller (BET) surface area of the as-synthesized products was measured to be 99.77 m(2)g(-1). The Barrett-Joyner-Halenda (BJH) model analysis showed that the as-prepared CuS materials had a main pore size distribution of around 25 nm. CV curves, LSV of CuS for oxygen electroreduction and CP curves showed that the as-prepared CuS nanospheres were potential candidates which can be used as cathode catalysts for the oxygen reduction reaction (ORR) in alkaline media.     

A versatile approach for the fabrication of Au hollow nanoparticles based on poly(styrene-co-2-aminoethyl methacrylate) template

The hollow Au nanospheres were successfully prepared by the template method. The poly(styrene-co-2-aminoethyl methacrylate hydrochloride) (P(St-co-AEMH)) nanoparticles synthesized by the emulsion polymerization were used as the templates. After coating by Au colloidal nanoparticles and the formation of Au shells, the interior templates were etched out by sulfuric acid, leading to the formation of Au hollow nanospheres. The structure and morphology of the nanoparticles and hollow nanospheres were carefully investigated by the fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDX), wide-angle X-ray diffractometer (WAXD), and thermal gravimetric analysis (TGA) techniques.     

高分散度Fe3O4纳米球的粒径控制合成及磁性能

采用CTAB作保护荆,在较低温度下,成功地制备出高分散度的Fe3O4纳米材料.通过改变反应条件和保护刺的种类,可在20～360nm范围内有效调控Fe3O4纳米颗粒的粒径.利用X射线衍射仪、透射电子显微镜和扫描电子显微镜等对样品的晶体结构、粒径、形貌和化学组成进行了分析.结果表明:所得Fe3O4纳米晶的粒径均匀,形貌为球形,分散度好.利用振动样品磁强计测量了室温下140nm粒径样品的磁性能.结果表明,Fe3O4纳米材料具有典型的软磁特性.     

Coprecipitation-assisted hydrothermal synthesis of PLZT hollow nanospheres

Lanthanum-modified lead zirconate titanate Pb_1−xLa_x(Zr_1−yTi_y)O₃ (PLZT) hollow nanospheres have been successfully prepared via a template-free hydrothermal method using the well-mixed coprecipitated precursors and the KOH mineralizer. The structure, composition, and morphology of the PLZT hollow nanospheres were characterized by XRD (X-ray diffraction), ICP (inductive coupled plasma emission spectrometer), FTIR (Fourier transform infrared spectra), TG/DTA (thermogravimetric analysis and differential thermal analysis), TEM (transmission electron microscopy) and SEAD (selected area diffraction). The results show that the composition and the morphology control of the PLZT products are determined by the KOH concentration. The PLZT hollow nanospheres with uniform size of about 4 nm were synthesized in the presence of 5 M KOH. The crystalline nanoparticles can be prepared at dilute KOH, in contrast to the amorphous powders prepared at concentrated KOH. Formation mechanisms of the PLZT hollow nanospheres are also discussed.