GaN纳米棒的催化合成及其发光特性

使用稀土元素Tb作催化剂, 通过氨化溅射在Si(111)衬底上的Ga2O3/Tb薄膜, 成功制备出GaN纳米棒. X射线衍射测试显示, GaN纳米棒具有六方结构. 利用扫描电子显微镜和高分辨透射电子显微镜观察分析得出, 纳米棒为单晶GaN, 纳米棒的直径为50-150 nm, 长度约10 μm. 光致发光谱在368.6 nm处有一强的紫外发光峰, 说明纳米棒具有良好的发光特性. 讨论了GaN纳米棒的生长机制.     

微波固相合成氧化锌纳米棒

通过前驱体的微波固相热分解法快速合成了氧化锌纳米棒, 其直径在60～385 nm之间, 长可达数微米. 前驱体则通过一步室温固相反应制备. 用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、能量色散X射线分析(EDX)和透射电子显微镜(TEM)对产物的结构和形貌进行了表征. 同时, 对氧化锌纳米棒的光致发光(PL)性能作了测试, 结果表明在355 nm处有一个明显的近带隙发射峰. 另外, 对比实验表明, 微波辐射在氧化锌纳米棒的形成过程中起了关键性作用, 并对其形成机理进行了初步探讨.     

分等级球状TiO2纳米结构的合成、表征和光催化活性

以TiCl3作为钛源,添加聚丙烯酰胺(PAM)和尿素,采用水热方法合成了分等级球状TiO2纳米结构。利用场发射扫描电子显微镜(FESEM)、X射线粉末衍射(XRD)、Raman光谱、氮气吸附-脱附分析和紫外-可见漫反射光谱(UV-VisDRS)对产物的形貌、晶相组成、孔结构和紫外-可见光谱性质进行了表征。结果表明,制备的直径为400～600nm的球状TiO2纳米结构由粒径为20～40nm的纳米粒子组装而成。PAM和尿素对分等级球状TiO2纳米结构的形貌和晶相组成有着重要影响。对紫外光照射下分等级球状TiO2纳米结构在甲基橙降解中的光催化活性也进行了研究。     

生物分子辅助溶剂热合成硫化锑纳米棒

以SbCl3和L-胱氨酸为反应原料,采用溶剂热法在170℃反应12h,制得硫化锑(Sb2S3)纳米棒.X射线衍射(XRD)、能量分散光谱(EDS)和X射线光电子能谱(XPS)研究表明所得产物为典型的Sb2S3正交结构.场发射扫描电子显微镜(FESEM)和透射电子显微镜(TEM)研究显示,Sb2S3纳米棒长为3～6μm,平均直径约为150nm.讨论了不同反应时间对Sb2S3的形成及其形貌的影响,并根据实验结果对所合成的一维纳米棒可能的形成机理进行了简单的探讨.     

室温固相化学反应合成表面修饰的碘化铅纳米棒

以硝酸铅和碘化钾为原料, 在体系中添加表面活性剂聚乙二醇(PEG), 采用一步室温固相化学反应制备出聚乙二醇表面修饰的碘化铅纳米棒, 利用X射线衍射, 红外光谱, 透射电子显微镜, 扫描电子显微镜, 热分析和元素分析等手段对其进行了表征. 实验结果表明: 在体系中添加的表面活性剂PEG不仅与碘化铅纳米棒发生了化学键合作用, 而且对产物形貌的控制起到决定作用, 形成了表面键合有聚乙二醇的碘化铅纳米棒, 其中被PEG600修饰的碘化铅纳米棒粗细均匀, 表面光滑, 直径约为100 nm, 长度达2 μm.     

基底对电沉积制备ZnO纳米棒阵列的影响

采用恒电位电沉积方法, 在未经修饰的ITO导电玻璃基底上通过控制实验条件制备出不同形貌的纳米ZnO结构, 而在经过ZnO纳米粒子膜修饰后的ITO导电玻璃基底上, 制备出透明、高取向、粒径小于30 nm的ZnO纳米棒阵列. 用扫描电子显微镜(SEM)、X射线衍射(XRD)以及透射光谱对制备出的ZnO纳米棒阵列的结构、形貌和透明性进行了表征. 测试结果表明, ZnO纳米棒阵列的平均直径为21 nm, 粒径分布窄, 约18～25 nm, 择优生长取向为[001]方向, 垂直于基底生长. 当入射光波长大于400 nm时, ZnO纳米棒阵列的透光率大于95%.     

Se和Se@C纳米棒的选择合成

通过调节葡萄糖浓度,采用十六烷基三甲基溴化铵(CTAB)辅助水热法选择合成了Se和Se@C纳米棒,并用扫描电镜(SEM)、透射电镜(TEM)、粉末X射线衍射(XRD)和X射线能谱分析(EDS)对产物进行了表征。结果表明,产物Se纳米棒直径200～300 nm,长达数微米;Se@C纳米棒长达数微米,内核直径200～00 nm,壳厚约30 nm。初步探讨了Se和Se@C纳米棒的生长机制。     

ZnO纳米棒薄膜的湿化学法制备及光致发光特性

在80 ℃水浴下, 采用简易的湿化学法在不导电玻璃基底上制备了ZnO纳米棒阵列, 利用X射线衍射仪(XRD)和场发射扫描电镜(FE-SEM)对样品的结构形貌进行了表征. 结果表明, 晶化30 min所得产物为六方纤锌矿相的ZnO纳米棒, 直径大约为80~90 nm. 为了分析不同的低温退火温度和退火气氛对其光致发光性能的影响, 研究了ZnO纳米棒薄膜在不同的后处理条件下的光致发光谱(PL). 实验结果表明, 在O₂气氛下于450 ℃退火1 h后, ZnO纳米棒薄膜的红光发射(约650 nm)强度相对在空气和5%H₂/95%N₂气氛下退火的样品变得更强, 而且该样品的激发波长范围(200~370 nm)与近紫外发光二极管(LEDs)的发射波长范围(350~420 nm)匹配得很好.     

TiO2/Au纳米棒阵列的制备及其光催化性能

采用电沉积和旋转涂膜相结合的方法成功制备了高度有序的TiO2/Au纳米棒阵列催化剂.扫描电镜和透射电镜结果表明,TiO2薄膜均匀地包覆在Au纳米棒的表面,形成核壳型的一维阵列结构.X射线衍射分析表明所获得TiO2为(101)晶面优先生长的锐钛矿晶相.紫外-可见漫反射光谱显示,由于Au和TiO2间肖特基结的存在造成吸收红...     

利用牛血清蛋白合成CdS纳米棒和网状纳米线

采用简单易控、对环境友好的矿化方法, 利用牛血清蛋白(BSA)做模板, 通过Cd2+与硫代乙酰胺(TAA)反应制备了形貌均一的CdS纳米棒和网状纳米线. 分别采用透射电子显微镜(TEM)、X射线能谱(EDS)、X射线衍射(XRD)、荧光(PL)发射谱和导电原子力显微镜(C-AFM)等方法对不同实验温度下制备的CdS样品的结构形貌、成分组成和光学性质及微区电子传输行为进行了表征. 结果表明: 在实验反应温度为20 ℃时, 得到的产物为单分散性好的CdS 纳米棒, 长度为250 nm, 直径为30 nm; 在50 ℃时, 得到网状CdS纳米线, 其长度为2-3 μm; CdS纳米棒和网状纳米线均为立方相闪锌矿结构. 荧光性质的测试表明, CdS纳米棒和网状纳米线具有优良的荧光性能, 电流-电压(I-V)特性的表征表明CdS纳米线具有很好的电导特性.     

Template-free chemical route to ultrathin single-crystalline films of CuS and CuO employing the liquid-liquid interface

Ultrathin films of CuS and CuO have been obtained at the liquid-liquid interface by the reaction of copper cupferronate solution in toluene with Na(2)S or NaOH in aqueous solution. The films are generally single crystalline and around 40 nm thick. The thickness and crystallinity of the films are determined by the reactant concentrations and reaction conditions. The films have been characterized by electron microscopy and atomic force microscopy besides X-ray diffraction. Sonication of the films produces nanocrystals and nanorods which are also single crystalline.     

CuS/TiO2纳米管异质结阵列的制备及光电性能

利用水热反应制备了CuS/TiO2纳米管异质结阵列,采用场发射扫描电子显微镜(FESEM)、透射电子显微镜(TEM)和X射线衍射谱(XRD)等手段表征了异质结阵列的表面形貌和晶体结构.电流-电压曲线结果表明,CuS/TiO2纳米管异质结阵列具有明显的整流效应.根据表面光电压谱和相位谱,在376～600 nm之间,CuS/TiO2纳米管异质结阵列表现为p型半导体特征,电子在表面聚集;在300～376 nm之间表现为n型半导体特征,空穴在表面聚集;在376 nm处异质结阵列的表面光伏响应为零.CuS/TiO2和CuS/ITO之间界面电场的不同导致异质结在不同波长范围内表面电荷聚集的差异.光电化学性能测试发现,以CuS/TiO2纳米管异质结阵列为光阳极组成的光化学太阳电池,在大气质量AM 1.5G,100 mW/cm2标准光强作用下具有0.4%的光电转换能力.     

Single-Source Molecular Precursor for Synthesis of Copper Sulfide Nanostructures

As a new precursor, [bis(thiosemicarbazide)copper(II)]chloride; ([Cu(TSC)₂]Cl₂), complex was used in thermal decomposition process for the synthesis of Cu₂S nanocrystals. The steric hindrance of the precursor raises the need of using co-surfactant, therefore oleylamine (C₁₈H₃₇N) and triphenylphosphine (C₁₈H₁₅P) were applied as solvent and surfactant of the reaction. CuS nanocrystals were synthesized via hydrothermal decomposition of [bis(thiosemicarbazide) copper(II)] without any surfactant. The products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and photoluminescence spectroscopy. Synthesized copper sulfide nanostructures have average size of 20–50?nm. Finally, optical properties of the products were examined and investigated by PL spectra.     

硫化铜空心球的合成和生长机理及其在抗肿瘤中的应用

以Cu(NO_3)_2·3H_2O,H_2C_2O_4和Na_2S·9H_2O为原料,利用简易水热方法合成了笼状硫化铜空心球。所得产物用X射线衍射(XRD)、场发射扫描电子显微镜(FE-SEM)、透射电子显微镜(TEM)和高分辨透射电子显微镜(HRTEM)进行了表征,并研究了其可能的形成机理。所得CuS空心球具有较高的光热转换性能,在近红外光辐照下,对肿瘤细胞具有明显的光热毒性。     

Synthesis and characterization of CdIn(2)S(4) nanorods by converting CdS nanorods via the hydrothermal route

The ternary semiconductor CdIn(2)S(4) nanorods were synthesized by a method based on CdS nanorods via the hydrothermal route, in which CdS nanorods were converted by reaction with InCl(3) and thiourea in aqueous solution. Transmission electron microscopy (TEM) images revealed that the typical sizes of the CdIn(2)S(4) nanorods were 10-30 nm in diameter and 200-1000 nm in length. X-ray photoelectron spectra (XPS) analysis of the surface stoichiometry (CdIn(2.03)S(4.15)) and room-temperature Raman spectrum (RS) were recorded. The influences of reaction temperature, time, and sulfur sources on the formation for CdIn(2)S(4) nanorods were investigated. A possible formation mechanism of the CdIn(2)S(4) nanorods was also proposed.     

Copper Sulfide Wire as a Selective Fiber in Solid-Phase Microextraction

Summary A copper wire coated with copper sulfide (CuS) was investigated as fiber for solid-phase microextraction (SPME). The fibers seem very effective for extraction of aliphatic alcohols and amines from aqueous samples. Optimum conditions for the preparation and conditioning of the fibers are presented. Scanning electron microscopy shows the formation of a porous CuS layer with a thickness of ca. 9 m. The calibration graph for benzyl alcohol was linear in the range 10–100 ppb. The detection limit for benzyl alcohol and GC-FID was 2 ppb (S/N=3).     

Preparation and characterization of gadolinium hydroxide single-crystalline nanorods by a hydrothermal process

The Gd(OH)3 nanorods with diameters of ca.40-60 nm and lengths of more than 400-550 nm have been prepared by a novelhydrothermal technique.The structural features and chemical composition of the nanorods were investigated by X-ray diffraction(XRD),transmission electron microscopy(TEM),and field emission scanning electron microscope(FESEM),selected areaelectron diffraction(SAED),and high resolution transmission electron microscopy(HRTEM).The possible mechanism for theformation of Gd(OH)3 nanorods was proposed.     

Seeded high yield synthesis of short Au nanorods in aqueous solution

Short gold nanorods of average lengths ranging between 20 and 100 nm (with corresponding aspect ratios of 2 and 4) were synthesized in excellent yield (approximately 97%). These nanorods were characterized by dark-field microscopy, UV-visible spectrophotometry, and transmission electron microscopy. Temporal evolution of rod shape had also been followed by UV-visible spectrophotometry and transmission electron microscopy and indicates that the nanorods briefly increase in length, then increase slightly in width, as they grow. The effect of the synthetic parameters on the rod dimension and yield was explored to find out suitable conditions to produce short nanorods; short nanorods have both plasmon bands in the visible region of the spectrum, which is a valuable property for sensor applications.