共查询到20条相似文献,搜索用时 15 毫秒
1.
更大的比表面积、更丰富的界面组成及更高效的传质路径是构筑多元催化体系,实现催化剂效率提升的关键.中空纳米纤维具有的多元空腔结构赋予其比表面积和界面组成上广阔的调变空间,使其成为制备高效异相催化剂的理想平台.静电纺丝技术的发展为中空纳米纤维的可控制备提供了更简易高效的方法,促进了中空纳米纤维的结构创新和应用扩展.本文从构筑策略、结构特点及结构与性能的对应关系3个角度总结了基于静电纺丝法制备的不同组成和形态的中空纳米纤维材料在催化领域(包括光催化、电催化、热催化)应用中的独特优势.首先展示了创新的静电纺丝方法结合后续工艺制备的中空纳米纤维的不同结构形态,然后梳理了基于中空纳米纤维构筑高效催化剂的研究进展,最后展望了中空纳米纤维在催化领域应用的未来发展趋势,以期为高效异相催化剂的设计提供有益的参考. 相似文献
2.
3.
采用静电纺丝法制备的、平均直径通常小于1000 nm的刺激响应性电纺纳米纤维是一种可响应外界刺激而发生物理化学性能改变的智能聚合物纤维,由它形成的纤维膜具有比表面积大、孔隙率高、对外界刺激产生响应速度快等优点,因此在诸多领域显示出诱人的应用前景,是近年来受到国内外高度关注的一种智能纳米材料。本文首先归纳了制备刺激响应性电纺纳米纤维的三种方法。然后从成纤聚合物的合成或选用、纺丝液配制、静电纺丝和后处理4个方面讨论了制备过程中影响纳米纤维尺寸、结构和刺激响应性等性能的主要因素。接下来重点述评了除电场外的其他各种刺激响应性电纺纳米纤维的设计及其构建研究进展,另外介绍了这些刺激响应性电纺纳米纤维膜在分离与纯化、药物控制释放、伤口敷料、细胞培养、传感器与检测等方面的应用研究情况。最后,就它们的未来研究方向进行了展望。 相似文献
4.
Changling Li Nicha Chartuprayoon Wayne Bosze Karen Low Kyu Hwan Lee Jin Nam Nosang V. Myung 《Electroanalysis》2014,26(4):711-722
Camphor‐10‐sulfonic acid (HCSA) doped polyaniline (PANI)/poly(ethylene oxide) (PEO) composite nanofibers with different compositions (12 to 52 wt.% of PANI) were synthesized by an electrospinning method and their properties including optical, electrical and sensing were systematically investigated. FT‐IR shows that an increase of IR absorbance ratios of aromatic C? C stretching vibration of benzenoid rings of PANI to C? O? C symmetric vibrational modes of PEO confirmed that the PANI content in nanofiber mats increased proportionally with increase in PANI content in electrospinning solution. The band gap of PANI was determined to be 2.5 eV using UV‐Vis spectroscopy. The electrical conductivities of the nanofibers increased with an increase in the PANI content in the nanofibers. Additionally, the sensitivity toward NH3 increased as the PANI content increased, but branched nanofibers reduced sensing response. The humidity sensitivity changed from positive to negative as the PANI content increased. The electron transport mechanism was studied by measuring the temperature dependence electrical resistivity. The negative temperature coefficient of resistance revealed a semiconducting behavior for the PANI/PEO nanofibers. The activation energy, calculated by Arrhenius plot, increased as the PANI content decreased. The power law indicated that electrons were being transported in a three dimensional matrix, and the longer hopping distance required more hopping energy for electron transport. 相似文献
5.
6.
二氧化硅@聚合物同轴纳米纤维 总被引:1,自引:0,他引:1
The preparation and formation mechamsm ot silica/polyvinylpyrrolidone(PAN) coaxial nanofibers were presented in this paper. The PVP-PAN composite nanofibers were obtained via an electrospinning technique, while SiO2 nanoparticles were prepared according to a Stoeher method. The measurements of water contact angle(WCA), the compared results of silica coating PVPPAN composite nanofibers with PAN nanofibers indicate that much PVP resided on the composite nanofiber surface, which resuks in the occurrence of SiO2@polymer coaxial nanofibers due to the formation of hydrogen bonding between silica and composite nanofibers and subsequent adsorption of silica on the fiber surface. 相似文献
7.
Linlin Li Dr. Shengjie Peng Yanling Cheah Yahwen Ko Peifen Teh Grace Wee Dr. Chuiling Wong Prof. Madhavi Srinivasan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(44):14823-14830
Hierarchical CaCo2O4 nanofibers (denoted as CCO‐NFs) with a unique hierarchical structure have been prepared by a facile electrospinning method and subsequent calcination in air. The as‐prepared CCO‐NFs are composed of well‐defined ultrathin nanoplates that arrange themselves in an oriented manner to form one‐dimensional (1D) hierarchical structures. The controllable formation process and possible formation mechanism are also discussed. Moreover, as a demonstration of the functional properties of such hierarchical architecture, the 1D hierarchical CCO‐NFs were investigated as materials for lithium‐ion batteries (LIBs) anode; they not only delivers a high reversible capacity of 650 mAh g?1 at a current of 100 mA g?1 and with 99.6 % capacity retention over 60 cycles, but they also show excellent rate capability with respect to counterpart nanoplates‐in‐nanofibers and nanoplates. The high specific surface areas as well as the unique feature of hierarchical structures are probably responsible for the enhanced electrochemical performance. Considering their facile preparation and good lithium storage properties, 1D hierarchical CCO‐NFs will hold promise in practical LIBs. 相似文献
8.
9.
10.
Electrochemical Detection of Hydrazine Based on Electrospun Palladium Nanoparticle/Carbon Nanofibers
In this work, we developed an electrochemical method for the detection of hydrazine based on palladium nanoparticle/carbon nanofibers (Pd/CNFs). Pd/CNFs were prepared by electrospinning technique and subsequent thermal treatments. The electrocatalytic behaviors of Pd/CNFs modified glassy carbon electrode (Pd/CNF‐GCE) for hydrazine oxidation were evaluated by cyclic voltammetry (CV), an obvious and well‐defined oxidation peak appeared at ?0.32 V (vs. Ag/AgCl). The mechanism of the oxidation of hydrazine at Pd/CNF‐GCE was also studied, which demonstrated an irreversible diffusion‐controlled electrode process and a four‐electron transfer involved in the overall reaction. Furthermore, the wide linear range, low detection limit, good reproducibility and excellent storage stability were obtained utilizing differential pulse voltammetry (DPV). 相似文献
11.
利用电纺丝技术制得钯/碳纳米纤维复合材料(Pd/CNFs),并将其用于修饰玻碳电极Pd/CNF-GCE/CME.Pd/CNF-GCE/CME对邻苯二酚和对苯二酚的氧化还原反应具有较高的电催化活性,显著提高了二者电化学反应的可逆性.考察了支持电解质的酸度对邻苯二酚和对苯二酚电化学响应的影响,选用0.1 mol/L PBS(pH 8.0)作为支持电解质.用微分脉冲伏安(DPV)法对邻苯二酚和对苯二酚进行选择性检测:当混合溶液中存在50 μmol/L对苯二酚时,邻苯二酚的氧化峰电流与其浓度在1~90 μmol/L范围内呈线性关系,检出限为0.3 μmol/L(S/N=3);当存在50 μmol/L邻苯二酚时,对苯二酚的氧化峰电流与其浓度在2~100 μmol/L范围内呈线性关系,检出限为1.0 μmol/L.另外,此修饰电极具有较好的重现性和较强的抗干扰能力.将此修饰电极用于模拟水样中邻苯二酚和对苯二酚的测定,结果令人满意. 相似文献
12.
Flavio Granato Matteo Scampicchio Andrea Bianco Saverio Mannino Chiara Bertarelli Giuseppe Zerbi 《Electroanalysis》2008,20(12):1374-1377
A new approach for the fabrication of disposable electrochemical surfaces is presented. Conducting fibers have been produced by a two‐step process. Firstly, a fine web mat composed of nylon‐6 and ferric chloride fibers (with diameters of about 200 nm) were electrospun on a flat collector. Afterwards, the electrospun mat was exposed to pyrrole vapor under controlled dry atmosphere until each nylon thread was fully coated with a conducting polypyrrole layer. The conducting fiber mat was finally integrated within an electrochemical cell and used as a disposable sensor device. The suitability of the sensor was tested using phosphate and carbonate organic anions. The large scale fabrication of conducting tissue, in the form of a fine web of spun nanofibers, is relatively fast and inexpensive, and it paves the way to the build up of new disposable electrodes. 相似文献
13.
14.
Electrospinning is a versatile technique providing highly tunable nanofibrous nonwovens. Many biomedical applications have been developed for nanofibers, among which the production of antimicrobial mats stands out. The production of scaffolds for tissue engineering, fibers for controlled drug release, or active wound dressings are active fields of research exploiting the possibilities offered by electrospun materials. The fabrication of materials for active food packaging or membranes for environmental applications is also reviewed. We attempted to give an overview of the most recent literature related with applications in which nanofibers get in contact with living cells and develop a nano-bio interface. 相似文献
15.
Deng-Guang Yu Chris Branford-White Xia-Xia Shen Xia-Fei Zhang 《Journal of Dispersion Science and Technology》2013,34(7):902-908
Solid dispersions of ketoprofen in nanofibers were prepared using electrospinning process with polyvinylpyrrolidone as the filament-forming polymer. Results from differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, and fourier-transform infrared suggested that ketoprofen was well distributed in the polymer nanofibers in an amorphous solid dispersion state due to the hydrogen bonding between them. In vitro wetting and dissolution tests showed that the nanofibers could absorb water from the wet papers and wetted within several seconds, and ketoprofen could be exhausted within 30 seconds. Electrospinning is a useful process for the preparation of solid dispersions. 相似文献
16.
电纺法及其在制备聚合物纳米纤维中的应用 总被引:3,自引:0,他引:3
在介绍电纺法的基础上,对电纺法制备聚合物和导电聚合物纳米纤维的影响参数和电纺纤维的应用研究进行了综述,同时展望了该方法在制备聚合物纳米纤维方面存在的挑战和机遇。 相似文献
17.
静电纺丝法制备硫酸化的二氧化锆/二氧化硅复合纤维 总被引:1,自引:0,他引:1
将电纺丝技术与溶胶-凝胶技术相结合, 制备了SZ粒子分布于SiO2纤维外壁的硫酸化的二氧化锆/二氧化硅复合纤维. 与常见的SZ复合催化剂相比, 采用SiO2纤维负载SZ不仅可以解决粉体材料带来的难以与反应体系分离等弊病, 同时功能粒子SZ分布与纤维外壁的结构也提高了功能粒子的利用率. 相似文献
18.
Xiao‐Jun Huang Zhi‐Kang Xu Ling‐Shu Wan Christophe Innocent Patrick Seta 《Macromolecular rapid communications》2006,27(16):1341-1345
Summary: PANCMPCs containing phospholipid side moieties were electrospun into nanofibers with a mean diameter of 90 nm. Field emission SEM was used to characterize the morphologies of the nanofibers. These phospholipid‐modified nanofibers were explored as supports for enzyme immobilization due to the characteristics of excellent biocompatibility, high surface/volume ratio, and porosity, which were beneficial to the catalytic efficiency and activity of immobilized enzymes. Lipase from Candida rugosa was immobilized on these nanofibers by adsorption. Preliminary results indicated that the properties of the immobilized lipase on these phospholipid‐modified nanofibers were greatly promising.
19.
通过脱细胞技术制备了猪骨脱细胞基质(DBM),用胃蛋白酶消化DBM使其变为可溶形式,采用静电纺丝技术制备了含有DBM的左旋聚乳酸(PLLA)电纺纤维(PLLA/DBM),并对PLLA/DBM的形貌、亲水性、细胞相容性、成骨性能和体外矿化能力进行评价.研究结果表明,脱细胞处理能够有效去除骨组织中的细胞成分,使DNA含量显著下降.DBM经胃蛋白酶处理后溶于六氟异丙醇(HFIP),可进行静电纺丝,制备的PLLA/DBM[m(PLLA)∶m(DBM)=10∶0,9∶1,7∶3,5∶5]电纺纤维具有良好的亲水性,且无细胞毒性,对骨髓间充质干细胞的黏附及成骨分化有明显的诱导促进作用,体外生物矿化效果优良. 相似文献
20.
Sung In Jeong Melissa D. Krebs Christopher A. Bonino Saad A. Khan Eben Alsberg 《Macromolecular bioscience》2010,10(8):934-943
Alginate, a natural polysaccharide that has shown great potential as a cell scaffold for the regeneration of many tissues, has only been nominally explored as an electrospun biomaterial due to cytotoxic chemicals that have typically been used during nanofiber formation and crosslinking. Alginate cannot be electrospun by itself and is often co‐spun with poly(ethylene oxide) (PEO). In this work, a cell adhesive peptide (GRGDSP) modified alginate (RA) and unmodified alginate (UA) were blended with PEO at different concentrations and blending ratios, and then electrospun to prepare uniform nanofibers. The ability of electrospun RA scaffolds to support human dermal fibroblast cell attachment, spreading, and subsequent proliferation was greatly enhanced on the adhesion ligand‐modified nanofibers, demonstrating the promise of this electrospun polysaccharide material with defined nanoscale architecture and cell adhesive properties for tissue regeneration applications.