多形态ZnO纳米粒子的制备及其紫外—可见光吸收性能研究

选用失水山梨醇单油酸酯／反应物水溶液／环己烷制成微乳液等“微反应器”，在其中控制反应，制备出了具有球形及棒状、不规则片状与球形但呈细胞器状排布的纳米氧化锌。用透射电镜（TEM）、动态激光光微射（DLLS）与X－射线衍射对产物的结构、形态、大小与化学成分进行了表征。系统研究了反应体系的组分、配比、反应温度及分散方法等反应条件对“微反应器”与产物形态、大小的影响。探讨了ZnO纳米粒子的稳定性及其原因。并对ZnO纳米粒子的紫外—可见光吸收性能进行了表征。     

CeF_3纳米粒子的制备和尺寸控制

利用萃取体系中形成的反胶团为微反应器制备了CeF_3纳米粒子.并对粒子尺寸进行了有效调控.结果表明,通过改变有机相浓度、料液以及反萃液的组成等,可以控制粒子的成核、生长和团聚,有效地对所制备的CeF_3纳米粒子尺寸进行调控.Triton X-100对CeF_3纳米粒子的分散存在一个转折浓度,即随着Triton X-100浓度增大,粉体团聚行为增强,当达到转折浓度时,粉体开始解聚,分散性变好.     

纳米氧化镁的制备及其紫外屏蔽性能

纳米氧化镁的制备及其紫外屏蔽性能;苹果酸;纳米氧化镁;紫外屏蔽;溶胶 凝胶法     

溶胶-凝胶法制备玻璃表面CeO2-TiO2紫外吸收薄膜的研究

分别以Ce(NO3)3·6H2O和Ti(OC4H9)4为前驱体制备CeO2和TiO2溶胶,通过改变Ce/Ti摩尔比(0/10,1/9,2/8,3/7,4/6,5/5,6/4,7/3,8/2,9/1,10/0)得到一系列复合溶胶,采用提拉法在玻璃基片上制备了CeO2-TiO2紫外吸收膜层.利用紫外可见光谱、XRD对各溶胶以及溶胶沉积的薄膜进行了表征;用SEM观察了镀3层膜和镀7层膜样品的新鲜断面,得到膜厚,借以验证计算所得数据的可用性.结果表明,溶胶的颜色产生变化与溶胶中Ti3+浓度有关;由于CeO2和TiO2相互作用,复合溶胶及其膜层的紫外线吸收能力分别强于纯的CeO2和纯的TiO2,吸收曲线向长波方向移动;膜层中CeO2晶体会使膜而雾化,膜层内的Ce/Ti固溶体或当晶体微小和呈非晶态时,均不影响膜面质量;当薄膜达到一定厚度的时候,紫外线儿乎全部被阻隔;在临界厚度内,膜层越厚阻隔效果越好,且对可见光区域的透过率基本无影响,均在70%～80%.     

新型锌铝水滑石紫外吸收剂的制备及其紫外吸收性能

以有机紫外吸收剂2-苯基苯并咪唑-5-磺酸(PBSA)、N,N-二甲氨基苯甲酸(DABA)为有机原料,采用共沉淀法,合成了有机紫外吸收剂插层水滑石Zn2Al-LDH/PBSA和Zn2Al-LDH/DABA,并测定了所得到的样品的XRD、FT IR、薄膜紫外吸收性质和氧化催化活性。结果表明,当有机紫外吸收剂以阴离子的形式进入水滑石层间后,仍有良好的紫外吸收性能并在可见光区有很好的透光性;通过测定插层水滑石的氧化催化活性,与纯有机物相比,Zn2Al-LDH/PBSA和Zn2Al-LDH/DABA的氧化催化活性明显降低。合成的新型的插层水滑石有望在防晒产品中得到应用。     

溶剂萃取法制备Co(PO_3)_2超细微粉

本文用溶剂萃取法成功地制备了偏磷酸钴超细微粉并通过ＸＲＤ，ＩＲ，ＴＧ，ＤＴＡ，ＴＥＭ等实验对超细微粉的组成、结构进行了表征。     

新型锌铝水滑石紫外吸收剂的制备及其紫外吸收性能

以有机紫外吸收剂2-苯基苯并咪唑-5-磺酸(PBSA)、N,N-二甲氨基苯甲酸(DABA)为有机原料,采用共沉淀法,合成了有机紫外吸收剂插层水滑石Zn2Al-LDH/PBSA和Zn2Al-LDH/DABA,并测定了所得到的样品的XRD、FT IR、薄膜紫外吸收性质和氧化催化活性。结果表明,当有机紫外吸收剂以阴离子的形式进入水滑石层间后,仍有良好的紫外吸收性能并在可见光区有很好的透光性;通过测定插层水滑石的氧化催化活性,与纯有机物相比,Zn2Al-LDH/PBSA和Zn2Al-LDH/DABA的氧化催化活性明显降低。合成的新型的插层水滑石有望在防晒产品中得到应用。     

LaF3:Eu3+纳米粒子的水热法制备及发光性质研究

用水热法制备了LaF3及Eu^3＋掺杂的LaF3纳米粒子, 通过X射线粉末衍射（XRD）、透射电子显微镜（TEM）和荧光光谱（FS）对样品进行了表征. 结果表明： 所得的纳米粒子粒度均匀、结晶完好, 呈规则的六边形形状;研究了反应温度和时间对LaF3纳米粒子形成的影响, 初步探讨了纳米粒子的生长机制. 研究了掺杂Eu^3＋后的发光性质, 发现纳米粒子经高温煅烧后, 荧光强度有明显下降, 适宜的煅烧条件为600 ℃/6 h, Eu^3＋的掺杂量在5%（摩尔分数）时, 纳米粒子的荧光强度最强, 更高的掺杂浓度将导致荧光猝灭.     

溶剂萃取法制备Co(PO3)2超细微粉

本文用溶剂萃取法成功地制备了偏磷酸钴超细微粉并通过XRD，IR，TG，DTA，TEM等实验对超细微粉的组成、结构进行了表征。     

水热法制纳米CeO2膜及紫外吸收性能研究

以Ce(NO3)3.6H2O和CO(NH2)2为原料,采用水热法在玻璃基质上制备了CeO2纳米膜。研究了水热温度和时间对所制备纳米CeO2薄膜的抗紫外性能的影响。采用XRD、FT-IR、SEM、UV-Vis以及自动椭圆偏振仪等测试手段对CeO2纳米膜及粉体进行了表征。结果表明,水热法制备的薄膜,最佳的水热工艺条件为水热温度130℃加热7 h。在此条件下,制备的薄膜厚度达100nm,晶型较好,膜表面平整度较高,且具有优异的可见光透过性和紫外吸收特性。     

Structural Characterization of Zirconia Nanoparticles Prepared by Microwave-Hydrothermal Synthesis

Nanocrystalline zirconia powders have been prepared by microwave-hydrothermal synthesis starting from aqueous solution of ZrOCl₂·8H₂O. Results of investigations on the aqueous suspension stability of the washed zirconia nanopowders by dynamic light scattering showed that the suspension, constituted by superaggregates of nanoparticles (131 ± 10 nm), was stable up to 15 days. Nanopowders were investigated by means of transmission electron microscopy and small angle x-ray scattering measurements which proved that the zirconia nanopowder is constituted by small primary nanoparticles of ca. 8 nm that agglomerate forming bigger aggregates of 50 ± 1 nm.     

SEC Characterization of Au Nanoparticles Prepared through Seed-Assisted Synthesis

In this paper we report the use of size-exclusion chromatography (SEC) for rapid determination of the sizes and size distributions of Au nanoparticles (NPs) prepared by seed-assisted synthesis. Analytical separation of Au NPs was performed in a polymer-based column of pore size 400 nm. We characterized the sizes and size distributions of the Au NPs by using 10 mM sodium dodecyl sulfate (SDS) as mobile phase and obtained a linear relationship (R ² = 0.986) between retention time and size of Au NPs within the range 9.8–79.1 nm; the relative standard deviations of these retention times were less than 0.3%. These separation conditions were used to characterize the sizes and size distributions of Au NPs prepared by seed-assisted synthesis. In addition to observing the elution times of the Au NPs we also simultaneously characterized their size-dependent optical properties by spectral measurement of the eluting peaks by use of an on-line diode-array detector (DAD), i.e., monitoring of the stability of the Au NP products. By using this approach we found the presence of SDS was beneficial in stabilizing the synthesized Au NPs. We also found that the volume of Au metal ions used affected the sizes of the final products. SEC seems an efficient tool for characterizing the sizes of NPs fabricated by seed-assisted synthesis.     

Characterization of Nested Hollow Inorganic Fullerene-like Tungsten Disulfide Nanoparticles Prepared by Solid-Gas Reaction

Non-carbon inorganic fullerene-like(IF) nanoscale materials have recently attracted intense interest due to their nested hollow and nanotube structures,In this letter,IF-WS2 nanoparticles prepared by solid-gas reaction were characterized by X-ray diffraction,Scanning electron microscopy and transmission electron microscopy.The results show that the IF-WS2 nanoparticles have a nested hollow closed spherical structure with diameter of 100-150mm.     

Perylene Nanoparticles Prepared by Reprecipitation Method

Perylene nanoparticles with different sizes were prepared by reprecipitation method.It is found that the nanoparticles show size-dependent optical property.Electron diffraction patterns indicate that all the nanoparticles of different sizes are in crystalline state.The rapid growth of the nanoparticles during the aging process could be slowed down effectively by the addition of cationic or anionic surfactants.     

Characterization of Electrochromic WO3-Layers Prepared by Sol-Gel Nanotechnology

Stable tungsten oxide coating sols suitable for electrochromic applications were prepared by a modified peroxotungstic acid route. Layers up to 250 nm thickness could be deposited on ITO-coated and/or FTO-coated glass substrates in a single dip-coating process. Optoelectrochemical measurements were employed to determine the variation of the electrochromic properties (change in optical density (OD) and switching times) of WO3-layers, investigated as a function of coating parameters, such as chamber humidity and the temperature of heat treatment. High resolution transmission electron microscopy (HR-TEM) has shown that the optimized layers possess a partially crystalline morphology with nanocrystalline regions 2–3 nm in size.     

Preparation and Characterization of CdTe Nanoparticles in Zirconia Films Prepared by the Sol Gel Method

Two methods for the synthesis of CdTe nanoparticles in zirconia sol-gel films are demonstrated. The nanoparticles were obtained by chemical reduction of Te(IV) using reducing agent (hydrazine) or tin chloride. Particle sizes ranging from 6 to 20 nm in diameter could be prepared by varying the experimetal parameters. The size and crystalline structure of the particles were characterized by optical absorption, X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy. The film morphology was characterized by scanning force microscopy.The film obtained by SnCl₂ method is smooth and homogeneous. The dense structure of CdTe nanoparticles of a few nm in diameter is revealed. The films prepared with hydrazine are porous as a result of evolution of the decomposition gaseous products during the reduction.Advantages and disadvantages of the two methods are discussed.     

Synthesis and Characterization of Lead Sulfide Nanoparticles in Zirconia-Silica-Urethane Thin Films Prepared by the Sol-Gel Process

PbS nanocrystals (NCs) ranging between 4–8 nm were incorporated into Zirconium-Silica-Urethane (ZSUR) matrix obtained by the sol-gel method. The sizes of the particles were controlled by temperature treatment and by concentration of PbS in ZSUR matrix. The sizes of PbS NCs were determined by TEM measurements. The quantum size effect could also be extracted from optical absorption and photoluminescence spectra. The new matrix allows incorporation of up to 40% PbS forming a characteristic structure of dendrite by reacting lead acetate with ammonium thiocyanate in sol-gel matrix. The sol precursors of the matrix for Zirconium-Silica-Urethane contained zirconium oxide (ZrO₂) matrix solution, tetramethoxysilane (TMOS), 3-glycid oxypropyl trimethoxysilane (GLYMO) and polyethylene urethane silane (PEUS) synthesized separately. The ZrO₂ matrix solution was obtained from zirconium n-tetrapropoxide in propanol and acetic acid was used as a chelating agent to stabilize the zirconium oxide precursor.     

改良自乳化溶剂挥发法制备MePEG-PLGA纳米粒的研究

对改良自乳化溶剂挥发法制备甲氧基封端的聚乙二阵-聚乳酸聚乙醇酸嵌段聚合物（MePEG—PL—GA）纳米粒的工艺进行优化,并对纳米粒子加以表征。以形态、粒径为指标,采用正交设计筛选出比较理想的制备工艺。以扫描电镜（SEM）和动态光散射粒度分析仪（DLS）对纳米粒的形态、大小和zeta电位进行研究。优化的制备方案：丙酮与乙醇体积比为3：3,MePEG—PLGA 30mg,聚乙烯醇（PVA）含量为3％,有机相与水相体积比为1：10。所得纳米粒为球形粒子,分布较均匀,平均粒径118．9nm。zeta电位为-1．7mV。改良自乳化溶剂挥发法适于MePEG—PLGA纳米粒子的制备。     

溶剂散逸自组装制备超疏水针垫阵列膜

利用溶剂散逸自组装方法,以聚苯乙烯、聚十二烷基丙烯酰胺-6-丙烯酰胺基己酸（CAP）和三氯甲烷为原料,在平滑的固体基质上制备了有序多孔膜,该膜上下表面可在外力作用下发生分离,得到具有微米级超疏水针垫阵列膜。 结果表明,制得的聚苯乙烯膜具备超疏水性质,与水接触角达158°。