同轴静电纺丝技术制备CeO2纳米管及光催化性能研究

采用同轴静电纺丝技术,以硝酸铈、聚乙烯吡咯烷酮、N,N-二甲基甲酰胺和氯仿为原料,制备了CeO2纳米管。用差热-热重分析、X射线衍射、扫描电镜、透射电镜和能谱仪对样品进行了表征。考察了CeO2纳米管对罗丹明B溶液的光催化性能。结果表明:所得到的产物属于立方晶系、空间群为O5H-FM3M的CeO2纳米管,CeO2纳米管平均外径约270 nm,内径约110 nm,管壁厚度约80 nm,长度>20μm,对其形成机理进行了分析。相对于CeO2纳米线、纳米带和CeO2颗粒,CeO2纳米管对罗丹明B的降解率有明显提高。     

同轴静电纺丝技术制备ZnO@CeO2纳米电缆

采用同轴静电纺丝技术,以硝酸铈、硝酸锌、聚乙烯吡咯烷酮、N,N-二甲基甲酰胺、甘油和氯仿为原料,制备了ZnO@CeO2 同轴纳米电缆。用差热–热重分析、X射线衍射、扫描电镜、透射电镜和能谱仪对样品进行了表征。结果表明,所得到的产物为ZnO@CeO2同轴纳米电缆,以晶态CeO2为壳层,晶态ZnO为芯层,电缆直径约90 nm,芯层直径约60 nm,壳层厚度约15 nm,电缆长度>300 μm,对其形成机理进行了分析。     

同轴静电纺丝技术制备Y_2O_3:Eu~(3+)@SiO_2豆角状纳米电缆与表征

采用同轴静电纺丝技术,以氧化钇、氧化铕、正硅酸乙酯(C8H20O4Si)、无水乙醇、PVP和DMF为原料,成功制备出大量的Y2O3:Eu3+@SiO2豆角状纳米电缆.用TG-DTA,XRD,SEM,TEM和荧光光谱等分析技术对样品进行了系统地表征.结果表明,得到的产物为Y2O3:Eu3+@SiO2豆角状纳米电缆,以无定型SiO2为壳层,晶态Y2O3:Eu3+球为芯,电缆直径约为200nm,内部球平均直径约150nm,壳层厚度约为25nm,电缆长度300μm.纳米电缆内部为球状结构,沿着纤维长度方向有序排列,形貌均一.Y2O3:Eu3+@SiO2豆角状纳米电缆在246nm紫外光激发下,发射出Eu3+离子特征的波长为614nm的明亮红光.对其形成机理进行了初步讨论.     

Ag/C同轴纳米电缆的制备

采用十六烷基三甲基溴化铵(CTAB)辅助水热法合成了Ag/C同轴纳米电缆,并用SEM、TEM、XRD和EDS对产物进行了表征。结果表明,产物为长达数十微米,内核直径80～100 nm,壳厚约100 nm的纳米电缆。初步探讨了Ag/C同轴纳米电缆的生长机制。     

同轴三层纳米电缆NiO@SiO2@TiO2的制备与表征

采用静电纺丝技术, 通过改进实验装置, 成功地制备出了NiO@SiO₂@TiO₂同轴三层纳米电缆. 采用差热-热重(TG-DTA)分析、X射线衍射(XRD)分析、傅立叶变换红外光谱(FTIR)分析、扫描电子显微镜(SEM)分析和透射电子显微镜(TEM)等分析技术对样品进行表征, 结果表明, 所得产物为NiO@SiO₂@TiO₂同轴三层纳米电缆, 内层为NiO, 直径大约为40～50 nm|中间层为SiO₂, 厚度大约为40～45 nm|外层为TiO₂, 厚度大约为45～50 nm. 对NiO@SiO₂@TiO₂同轴三层纳米电缆的形成机理进行了讨论.     

静电纺丝技术制备NiO@Al2O3@TiO2同轴三层亚微米电缆及其形成机理

采用静电纺丝技术,通过改进实验装置,采用同轴三喷嘴实验装置代替传统的单喷嘴实验装置,在最佳的纺丝条件下制备了[Ni(CH3COO)2+PVP]@[Al(NO3)3+PVP]@[Ti(OC4H9)4+CH3COOH+PVP]前驱体复合电缆,将其进行热处理,制备出了NiO@Al2O3@TiO2同轴三层纳米电缆. 采用差热-热重(TG-DTA)、X射线衍射(XRD)、傅立叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)等分析技术对样品进行了表征. 结果表明,所得产物为NiO@Al2O3@TiO2同轴三层纳米电缆. 纳米电缆芯层为NiO,直径大约为137.83±8.85 nm;中间层为Al2O3,厚度大约为215.11±8.66 nm;壳层为TiO2,厚度大约为156.26±16.50 nm. 对NiO@Al2O3@TiO2同轴三层纳米电缆的形成机理进行了讨论.     

ZnO@SiO_2同轴纳米电缆的静电纺丝技术制备与表征

采用同轴静电纺丝技术,以硝酸锌、正硅酸乙酯(C8H20O4Si)、无水乙醇、聚乙烯吡咯烷酮(PVP)和N,N-二甲基甲酰胺(DMF)为原料,成功制备出大量的ZnO@SiO2同轴纳米电缆。用TG-DTA,XRD,SEM,TEM,FTIR等分析技术对样品进行了表征。结果表明,得到的ZnO@SiO2同轴纳米电缆的壳层为无定型SiO2,厚度为50nm,芯轴为晶态ZnO,电缆直径为300~450nm,长度大于300μm。探讨了ZnO@SiO2同轴纳米电缆的形成机理。     

同轴静电纺丝法在纳米中空TiO2纤维中填充Ag的应用

以聚乙烯吡咯烷酮(PVP)溶胶/钛酸四正丁酯和PVP溶胶/银颗粒为前驱体, 以共轴静电纺丝法制备了银填充的TiO2中空纳米纤维. 将双组分纤维在200 ℃下热处理去除乙醇与表面吸附水后, 继而在空气气氛中焙烧至600 ℃, 可以得到在内表面上沉积银颗粒的TiO2纳米管, 银颗粒的直径为5-40 nm, TiO2纳米管的外径150-300 nm, 管臂厚10-20 nm. 用红外吸收光谱(IR)、X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等测试手段对超细纤维进行了表征. 中空纤维的直径和管壁可以通过改变电纺参数来调节. 与Ag-TiO2纳米纤维、TiO2纳米中空纤维、TiO2纳米纤维及TiO2纳米粉体相比较, Ag颗粒填充的TiO2纳米中空纤维在光分解亚甲基蓝上表现出了更好的光催化性能.     

同轴静电纺丝法在纳米中空TiO2纤维中填充Ag的应用

以聚乙烯吡咯烷酮（PVP）溶胶/钛酸四正丁酯和PVP溶胶/银颗粒为前驱体,以共轴静电纺丝法制备了银填充的TiO2中空纳米纤维.将双组分纤维在200℃下热处理去除乙醇与表面吸附水后,继而在空气气氛中焙烧至600℃,可以得到在内表面上沉积银颗粒的TiO2纳米管,银颗粒的直径为5-40nm,TiO2纳米管的外径150-300nm,管臂厚10-20nm.用红外吸收光谱（IR）、X射线衍射（XRD）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）等测试手段对超细纤维进行了表征.中空纤维的直径和管壁可以通过改变电纺参数来调节.与Ag-TiO2纳米纤维、TiO2纳米中空纤维、TiO2纳米纤维及TiO2纳米粉体相比较,Ag颗粒填充的TiO2纳米中空纤维在光分解亚甲基蓝上表现出了更好的光催化性能.     

NH4F/H3PO4体系中阳极氧化法制备TiO2纳米管阵列

以价廉的Ni板代替常用的Pt片为阴极,纯钛为阳极,采用电化学阳极氧化法在NH4F-H3PO4体系中制备出TiO2纳米管阵列.详细研究了制备参数(溶液酸度、氟离子浓度、外加电压和氧化时间)对所获纳米管阵列形貌的影响.采用场发射扫描电镜(FE-SEM)和X射线衍射(XRD)对样品的形貌和晶相结构进行了表征.在最优化的条件下,可以获得形貌规整、表面干净、有序的TiO2纳米管阵列.纳米管阵列的平均管径为60 nm.管长约530 nm.采用阳极氧化法制备的纳米管阵列是非晶态的.经400℃热处理2 h后,可以转变为锐钛矿相.实验结果还发现,经过热处理后,纳米管阵列变得更为有序,管径扩大至约95 nm.     

同轴静电纺丝法在纳米中空Ti02纤维中填充Ag的应用

以聚乙烯吡咯烷酮(PVP)溶胶,钛酸四正丁酯和PVP溶胶,银颗粒为前驱体,以共轴静电纺丝法制备了银填充的TiO2中空纳米纤维.将双组分纤维在200℃下热处理去除乙醇与表面吸附水后,继而在空气气氛中焙烧至600℃.可以得到在内表面上沉积银颗粒的TiO2纳米管,银颗粒的直径为5-40 nm,TiO2纳米管的外径150-300 nm.管臂厚10-20 nm.用红外吸收光谱(IR)、X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等测试手段对超细纤维进行了表征.中空纤维的直径和管壁可以通过改变电纺参数来调节.与Ag-TiO2纳米纤维、TiO2纳米中空纤维、TiO2纳米纤维及TiO2纳米粉体相比较,Ag颗粒填充的TiO2纳米中空纤维在光分解亚甲基蓝上表现出了更好的光催化性能.     

NiO@SnO2@Zn2TiO4@TiO2同轴四层纳米电缆的制备、表征及形成机理研究

采用静电纺丝技术, 通过改进实验装置, 在最佳的纺丝条件下制备了[Ni(CH₃COO)₂＋PVP]@[SnCl₄＋PVP]@[Zn(CH₃COO)₂＋PVP]@[Ti(OC₄H₉)₄＋CH₃COOH＋PVP]前驱体复合电缆, 将其进行热处理, 制备出NiO@ SnO₂@Zn₂TiO₄@TiO₂同轴四层纳米电缆. 采用热重-差热(TG-DTA)、X射线衍射(XRD)、傅立叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)等分析技术对样品进行了表征. 结果表明, 所得产物为同轴四层纳米电缆, 芯层为NiO, 直径为35～55 nm|第二层为SnO₂, 厚度为30～50 nm|第三层为Zn₂TiO₄, 厚度为25～40 nm|壳层为TiO₂, 厚度为40～90 nm. 对同轴四层纳米电缆的形成机理进行了探讨.     

Sol-Gel Co-Electrospun LiNiO2 Hollow Nanofibers

Using a coaxial capillary spinneret electrospinning technique combined with the sol-gel method, the nickelic xerogel hollow nanofibers first were prepared and the polycrystalline LiNiO₂ hollow nanofibers were obtained after sintering. The obtained hollow nanofibers were about 500 nm to 4 µm in outer diameter, and were made up of 20 ～ 30 nm nanocrystals. The xerogel hollow nanofibers and those calcined at different temperatures were characterized by thermogravimetric (TG) analysis, Fourier transform infrared (FTIR) spectrum, x-ray diffractometry (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM).     

Surface Functionalization of PEO Nanofibers Using a TiO2 Suspension as Sheath Fluid in a Modified Coaxial Electrospinning Process

Convenient and integration fabrication process is a key issue for the application of functional nanofibers. A surface functionalization method was developed based on coaxial electrospinning to produce ultraviolet(UV) protection nanofibers. The titanium dioxide(TiO₂) nanoparticles suspension was delivered through the shell channel of the coaxial spinneret, by which the aggregation of TiO₂ nanoparticles was overcome and the distribution uniformity on the surface of polyethylene oxide(PEO) nanofiber was obtained. With the content of TiO₂ increasing from 0 to 3%(mass fraction), the average diameter of nanofibers increased from (380±30) nm to (480±100) nm. The surface functionalization can be realized during the electrospinning process to gain PEO/TiO₂ composite nanofibers directly. The uniform distribution of TiO₂ nanoparticles on the surface of nanofibers enhanced the UV absorption and resistance performance. The maximum UV protection factor(UPF) value of composite nanofibers reaches 2751. This work presented a novel surface-functionalized way for the preparation of composite nanofiber, which has great application potential in the field of micro/nano system integration fabrication.     

Silver Nanoparticles Filling in TiO2 Hollow Nanofibers by Coaxial Electrospinning

This study investigated the coaxial electrospinning process of silver filling in TiO₂ ultrafine hollow fibers using polyvinyl pyrrolidone (PVP) sol/titanium n-butyloxide (Ti(OC₄H₉)₄) and PVP sol/silver nanoparticles as pore-directing agents. The bicomponent fibers were heat treated at 200 °C and calcined at 600 °C. Silver particles having diameters of 5 to 40 nm were deposited on the inner surface of the long hollow TiO₂ nanofibers (outer diameter of 150.300 nm) with mesoporous walls (thickness of 10.20 nm). The morphological structure of the filled ultrafine hollow fibers has been studied by means of infrared (IR) spectrum, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The diameters and wall thicknesses of the hollow fibers could be tuned by adjusting the electrospinning parameters. Compared with other nanostructured TiO₂ materials, such as mesoporous Ag-TiO₂ blending fibers, TiO₂ hollow nanofibers, TiO₂ nanofibers, and TiO₂ powders, the silver filled TiO₂ hollow fibers exhibited a higher photocatalytic activity toward the degradation of methylene blue.