CTAB软模板法碳酸锶纳米棒制备

以六水氯化锶、氢氧化钠和尿素为原料,采用尿素水解均相沉淀法利用表面活性剂CTAB所形成的棒状胶束为软模板定向诱导制备出了晶形规整的碳酸锶纳米棒,利用扫描电子显微镜(SEM)和X射线衍射仪(XRD)对其进行了表征。结果表明,碳酸锶纳米棒呈规则的直线状,长度在6μm以上,平均粒径约80nm,长径比达到70以上。对碳酸锶纳米棒的形成机理进行了初步的研究,最后进一步讨论了CTAB用量对粒子形貌的影响情况。     

海藻酸钠调控羟基磷灰石纳米棒的低温快速合成

以海藻酸钠为晶体生长调节剂, 在水热条件下制备了形貌均匀、高长径比的羟基磷灰石(Hydroxyapatite, HA)单晶纳米棒。通过X射线衍射(XRD)、傅里叶红外光谱(FT-IR)、场发射扫描电镜(FE-SEM)、透射电镜(TEM)以及同步热分析(TG/DSC)等测试方法对合成产物进行了表征, 探索了反应温度和时间对产物的结晶度、组成以及形貌的影响, 并提出了HA纳米棒的合理生长机理。研究表明, 80℃水热条件, 反应24 h, 对于均匀、低有机吸附量的HA单晶纳米棒合成较有利。对纳米棒的不同生长阶段的微结构分析表明: 晶体生长经历了成核、表面调控、继续生长和取向搭接四个阶段。     

模拟体液法快速合成羟基磷灰石纳米针及其吸附性能研究

采用模拟体液法快速制备羟基磷灰石(HA)纳米针,并研究了HA对牛血清蛋白质(BSA)的吸附性能。采用XRD、TEM、SEAD和FT-IR等分析方法表征样品。结果表明:1min即可快速制备宽约5nm,长为50～80nm且分散良好的HA纳米针,形貌和尺寸与人体中的HA极为相似;反应时间影响合成产物的形貌及物相,短时间内延长反应时间有利于HA纳米针的生长,但反应时间过长会导致HA再次反应生成Ca3(PO4)2;同时,快速制备的HA纳米针具有很强的吸附性能。     

HA-n-ZrO2核壳层复合陶瓷微粉材料的制备与表征

采用水热-沉积原位分步反应法.制备了羟基磷灰石(HA)-氧化锆(ZrO2)复合微粉,采用XRD和TEM对复合微粉的物相、形貌和大小进行了表征.对复合微粉进行模压成型、热处理制备了复合陶瓷试样,并测试其力学性能.结果表明:所得复合微粉以纳米级四方相ZrO2为"核心",逐层包覆HA,形成核-壳层结构(HA-n-ZrO2);...     

小型金纳米棒的制备

用种子生长法合成小型金纳米棒,改变合成参数可调控其形貌和性能。使用紫外-可见-近红外分光光度计和透射电子显微镜(TEM)测试和观察了金纳米棒的消光特性和形貌,研究了AgNO₃、十六烷基三甲基溴化铵(CTAB)和籽晶的用量对金纳米棒的形貌和性能的影响。结果表明：在不同条件下制备的金纳米棒具有良好的重现性。在(0.01 mol/L) AgNO3用量为0.035 mL、(0.1 mol/L) CTAB用量为11 mL、籽晶用量为1.1 mL的最佳条件下合成的金纳米棒,其长径比约为3.8,平均长度约为34 nm,形貌均匀性和分散性良好。这种小型金纳米棒可用于检测残留物福美双(Thiram)。     

TiO_2纳米颗粒/纳米棒阵列复合薄膜的制备及其光电催化性能

以金属钛箔为钛源,采用双氧水和盐酸体系,通过水热法制备合成TiO2纳米棒阵列薄膜,并通过调节双氧水和盐酸的用量,调控TiO2纳米棒阵列薄膜的微观形貌和物相构成。结合溶剂挥发自组装法将TiO2纳米颗粒引入纳米棒阵列中,得到复合型TiO2光催化剂。以亚甲基蓝为模拟污染物,考察TiO2复合薄膜的光催化活性。通过扫描电镜(SEM)和X射线衍射(XRD)测试对TiO2复合薄膜的物相和表面形貌等进行了表征,并采用电化学交流阻抗法(EIS)分析其表面电荷转移特性。TiO2纳米颗粒/纳米棒阵列复合薄膜在光电协同条件下,展示出高的光电催化活性。     

CTAB诱导的Fe_3O_4/聚苯胺、聚吡咯复合纳米材料的制备与表征

以Fe3O4纳米粒为原料,采用单体苯胺及吡咯进行表面原位聚合反应,分别制备了Fe3O4/聚苯胺(PANI)及Fe3O4/聚吡咯(PPY)两种复合纳米材料,经XRD、FT-IR、SEM表征,表明Fe3O4/PANI复合纳米微球粒径为40～60nm,Fe3O4/PPY纳米材料大小为100nm左右。研究发现在制备过程中,所得复合纳米材料的形貌受添加到聚合反应中十六烷基三甲基溴化铵(CTAB)阳离子表面活性剂的影响显著,在无CTAB的制备过程中,复合纳米材料形成纳米颗粒结构,而在加入CTAB的过程中,所得复合材料则呈丝状纳米结构。结果表明,可以通过调整CTAB的加入与否达到控制Fe3O4/PANI、PPY复合纳米材料形貌的目的。     

ZnCo_2O_4纳米颗粒的制备及其可见光催化性能研究

采用表面活性剂(CTAB)调制的方法成功制备尖晶石型Zn Co2O4纳米颗粒,利用X射线衍射仪(XRD)、扫描电子显微镜镜(SEM)、透射电子显微镜(TEM)以及紫外-可见(UV-Vis)分光光度计对采用CTAB调制与未采用CTAB调制制备的Zn Co2O4颗粒的结构、形貌以及催化降解性能进行了对比分析。结果表明,制备出的Zn Co2O4纳米颗粒平均粒径为15.6 nm,对刚果红可见光催化降解具有很好的光催化活性,降解效率高。     

超声化学法合成羟基磷灰石纳米棒

在37℃下的模拟体液中采用超声化学法制备羟基磷灰石(HA)纳米棒,研究了初始pH值和反应时间对合成磷酸钙产物晶相的影响.结果发现在初始pH＜7.5时产物为无水磷酸氢钙相和HA相的混合物,初始pH值≥7.5时产物为单一的HA相,延长超声波处理时间有利于羟基磷灰石晶相的生成,最佳的反应参数为初始pH≥7.5,反应时间在6h以上.利用TEM、FTIR对HA相产物进行表征发现,HA为含碳酸根羟基磷灰石,其形貌长度为200nm,直径为10～30nm的纳米棒,其在组成和形态上与生物体内的磷灰石相十分接近.     

盐酸浓度对TiO2纳米棒的影响

采用水热合成方法在透明导电玻璃上制备了TiO2纳米棒阵列,利用扫描电子显微镜(SEM)和X射线衍射仪(XRD)等手段对样品进行分析和表征。研究了盐酸浓度对阵列形貌和结构的影响,并针对其影响机理做了进一步的探讨。结果表明,TiO2纳米棒为金红石相,在盐酸与去离子水的比例为1.0时,TiO2纳米棒阵列生长方向垂直于衬底,排列整齐,组织均匀致密。     

Hydrothermal synthesis,characterization, and luminescence of BaWO4 nanorods

Barium tungstate (BaWO₄) nanorods were synthesized by a hydrothermal process with the assistant of cetyltrimethyl ammonium bromide (CTAB). The samples were analyzed by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and photoluminescence measurements. The XRD and FT-IR results show that BaWO₄ samples can be indexed as a pure tetragonal scheelite structure. The SEM results show that the morphologies are nanorods with a diameter about 45 nm and a length exceeding 1 μm. The CTAB and “oriented attachment” play key roles in the growth of BaWO₄ nanorods in the hydrothermal process. When excited at 265 nm, BaWO₄ nanorods show the intrinsic emission band centered at 467 nm. The calculated luminescence lifetime of WO₄ ^2? in BaWO₄ is 8.9 μs.     

介孔Zr（HPO4）2的合成及表征

以十六烷基三甲基溴化铵(CTAB)为模板剂,采用溶胶-凝胶法配合水热晶化合成了具有短程有序介孔结构的层状化合物Zr(HPO4)2。通过XRD、N2吸附、HRTEM等技术对样品的物相、孔结构和形貌进行了表征,结果表明,按n(CTAB)∶n(Zr)=0.8引入CTAB作为模板剂所合成的前驱体在120℃水热晶化48h,可以得到比表面积为66.9m2/g、孔容为0.11cm3/g、平均孔径为8.1nm的单相Zr(HPO4)2结晶化合物。     

Surfactant-assisted hydrothermal synthesis and characterization of WS2 nanorods

WS₂ nanorods with diameters of about 20–100 nm and lengths of about 0.1–2 μm were successfully synthesized by a simple hydrothermal method with the help of the surfactant Cetyltrimethylammonium Bromide (CTAB). As-prepared WS₂ samples are characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Moreover, the influence of surfactant CTAB on the formation of WS₂ nanorods was investigated. A possible three-step growth mechanism of WS₂ nanorods, in which initial nucleation, self-assembly (oriented aggregation), and subsequent crystal growth (Ostwald ripening) is involved, is proposed to explain the formation of WS₂ nanorods on the basis of observations of a time-dependent morphology evolution process.     

Shape and size control of ZnO nanostructures via a simple solution route

ZnO nanostructures with different morphologies were synthesized by condensing the Zn(OH)4(2-) precursors under hydrothermal conditions in the presence of a surfactant, cetyltrimethylammonium bromide (CTAB). Shape and size control of ZnO nanostructures was achieved by relatively simple variations of molar ratio of CTAB to Zn(OH)4(2-). With a higher molar ratio, ZnO nanotubes were obtained, whereas with a lower molar ratio, ZnO nanorods were formed; furthermore, with a moderate w value, the coexistence of ZnO nanorods and nanotubes was also observed. The photoluminescence of ZnO nanorods and nanotubes was also investigated.     

A simple and novel low-temperature hydrothermal synthesis of ZnO nanorods

A new simple low-temperature hydrothermal process without addition of any surfactant or complexing agent was put forward to synthesize uniform ZnO nanorods, in which hydrazine hydrate instead of NaOH was used as mineralizer. X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and UV-vis diffuse reflectance spectroscopy were used to characterize the product, the results of which reveal that uniform ZnO nanorods approximately 70 nm in width and 2 μm in length were formed at 150°C within 8 h. Prior to the hydrothermal process hydrazine hydrate reacted with ZnCl₂ solution to form a complex, and the complex slowly decomposed in the hydrothermal process. All these characteristics were favorable to this additive-free hydrothermal synthesis of ZnO nanorods. The text was submitted by the authors in English.     

N-Lauroyl sarcosine sodium salt mediated formation of hydroxyapatite microspheres via a hydrothermal route

Dandelion-like hydroxyapatite (HA) microspheres were successfully prepared using Ca(NO₃)₂·4H₂O and (NH₄)₃PO₄·3H₂O as raw materials and N-Lauroyl sarcosine sodium salt (Sar-Na) as template via a hydrothermal route. The chemical composition, structure, morphology and thermal properties of the samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscope (FTIR), Scanning electron microscope (SEM) and Thermal gravimetric analysis (TG), respectively. The results demonstrate that, Sar-Na has great impact on the morphology of HA. With increasing the amount of Sar-Na, the morphology of HA varies from nanograins to nanorods, finally grows into dandelion-like microstructure. The obtained dandelion-like HA microspheres about 6 μm in diameter are composed of radially oriented nanorods. Furthermore, the possible formation mechanism of morphology change is also discussed.     

The formation of WO3 nanorods using the surfactant-assisted hydrothermal reaction

Monoclinic tungsten oxide (WO₃) nanorods were grown using the hydrothermal method on a seeded W foil. The seed layer was formed by thermal oxidation of W foil at 400°C for 30 min. Cetyltrimethylammonium bromide (CTAB) or hexamethylamine (HMT) was used in the reactive hydrothermal bath, along with sodium tungstate dihydrate (Na₂WO₄.2H₂O) and hydrochloric acid (HCl). The concentration of CTAB was varied from 0.01 M to 0.07 M and the concentration of HMT was varied from 0.01 M and 0.05 M. The result showed that CTAB-assisted hydrothermal reaction produced WO₃ nanorods with 4–7 nm diameter, and provided that CTAB concentration was less than 0.07 M. WO₃ nanorods could not be obtained when CTAB concentration was 0.07 M. Columnar structured WO₃ was produced with the presence of HMT in the hydrothermal bath. This was due to decomposition of HMT to form hydroxyl ions (OH^?) that inhibited the growth of nanorods. Cyclic voltammetry (CV) analysis showed better electrochromic property of WO₃ nanorods compared to columnar structured WO₃.     

Gas sensing properties of ZnO nanorods prepared by hydrothermal method

ZnO nanorods are prepared by a hydrothermal process with cetyltrimethylammonium bromide (CTAB) and zinc powder at 182°C. The samples are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The gas sensing properties of the materials have been investigated. The results indicate that the as-prepared ZnO nanorods are uniform with diameters of 40–80 nm and lengths about 1 μm, the relatively high sensitivity and stability of these sensors made from ZnO nanorods demonstrate the potential for developing a new class of stable and very sensitive sensors.     

Synthesis and characterization of bundle-like structures consisting of single crystal Ce(OH)CO3 nanorods

Bundle-like structures consisting of single crystal cerium hydroxide carbonate (Ce(OH)CO₃) nanorods have been synthesized successfully by a hydrothermal method at 100 °C using cerium nitrate (Ce(NO₃)₃·6H₂O) as the cerium source, aqueous carbamide both as an alkaline and carbon source and cetyltrimethylammonium bromide (CTAB) as surfactant. X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) were used to characterize such bundle-like structures. SEM and TEM images show that Ce(OH)CO₃ bundle-like structures were composed of nanorods with diameters of ∼ 100 nm. The XRD pattern and electron diffraction (ED) pattern indicate that Ce(OH)CO₃ has a pure orthorhombic single crystal structure.     

酸-水热法辅以水热温度对钛材生物活性的影响

为提高医用钛材的生物活性,通过酸-水热复合法在其表面设计并制备了TiO_2纳米棒,探讨水热温度对钛表面TiO_2纳米棒形成的影响,然后对试样进行模拟体液生物活性实验,采用扫描电子显微镜(SEM)、能谱仪(EDS)和X射线衍射仪(XRD)分析手段研究了钛表面生成产物的形貌、元素组成和物相组成.结果表明:随着水热温度的增加,二氧化钛层的表面形貌发生改变,从片状到棒状,之后纳米棒发生团聚;试样中金红石相和锐钛矿相的衍射峰强度随水热温度的增加而增强;水热温度为130℃时,钛表面可以形成尺寸均匀、长度基本一致的TiO_2纳米棒,其厚度、长度和直径分别为2.5μm、150 nm和10 nm,且纳米棒是由锐钛矿型和金红石型TiO_2的混合相组成.模拟体液生物活性实验后,水热处理后材料表面有富含Ca、P的羟基磷灰石生成,而羟基磷灰石的形成主要与纳米棒的形成和膜层的厚度有关.其中,水热温度为130℃时形成的纳米棒结构较好,膜层较厚,其表面诱导磷灰石沉积的含量最多,具有较好的生物活性.