PbO2-TiO2镀液中掺杂Ce对制备钛基锌电积阳极材料性能的影响

为了寻找出性能更佳的电积锌用钛基二氧化铅阳极,将CeO2,Ce(NO3)2分别掺杂在电镀液中制备了Ti/PbO2-TiO2阳极.以SEM,XRD分析方法对其形貌、组成元素进行了表征,应用加速电解寿命测试和电化学试验进行了性能测试,分别考察了掺杂CeO2和Ce(NO3)2对PbO2-TiO2阳极稳定性及电催化活性的影响.结果表明:Ti/PbO2-TiO2+CeO2阳极的电催化活性较好,且掺杂CeO2能改善Ti/PbO2-TiO2的导电性,提高了阳极的稳定性,使其电解寿命增长;Ti/PbO2-TiO2+Ce(NO3)2阳极的电催化活性也较好,但并不能增加阳极寿命.     

静电纺丝制备Fe2O3-TiO2纳米纤维及光催化性能研究

采用静电纺丝法制备了Fe2O3掺杂纳米TiO2的有机无机PVP/Fe2O3-TiO2纤维,经高温焙烧得到Fe2O3-TiO2纳米纤维。利用差动-热重(DSC-TGA)、傅里叶红外光谱(FT-IR)、扫描电镜(SEM)、XRD和比表面积分析仪等对样品进行了表征。以10mg/L亚甲基蓝溶液为底物,研究了Fe2O3掺杂量和焙烧温度等对亚甲基蓝太阳光催化降解效果的影响。结果表明,掺杂量为0.08%、焙烧温度为500℃得到的Fe2O3-TiO2纳米纤维光降解效果最好,达到96.3%,重复使用7次降解率仍在90%以上。     

贵金属Pd离子掺杂纳米ZnSnO3的氢敏性能及掺杂机理

为了提高ZnSnO3的氢敏性能,以共沉淀法制备ZnSnO3并对其进行了贵金属Pd2＋掺杂.采用X射线衍射仪（X-ray diffraction,XRD）及透射电镜（transmission electron microscopy,TEM）对制备的气敏材料进行结构及形貌表征,并使用静态配气法测试了掺杂前后ZnSnO3的氢敏性能.结果表明：掺杂Pd2＋可显著提高ZnSnO3的氢敏性能.在工作温度为240℃、浓度为300×10-6的条件下,Pd2＋掺杂纳米ZnSnO3对氢气的灵敏度为12,是未掺杂时的3倍.基于第一性原理探讨气敏机理,计算结果表明：Pd2＋掺杂改变了ZnSnO3能带间的电子运动状态,使ZnSnO3费米能级由0.725 eV移动到1.035 eV,在费米能级附近产生新的电子峰,使其电导性能在气敏反应过程中改变更为明显.Pd2＋掺杂还使ZnSnO3表面吸附氧的能力显著增加,对提高氢敏性能起到了关键作用.     

掺杂Ca^2＋的NaCO2O4热电材料的热电性能分析

采用柠檬酸复合体（CAC法）法制备了纯NaCO2O4和掺杂金属Ca^2＋的NaCO2O4热电材料，采用XRD、SEM和热电性能测试等技术表征了其结构、表面及断面形貌和热电性能，考察了其高温热电性能以及掺杂金属离子Ca^2＋对NaCO2O4结构的影响。结果表明，利用CAC法制备的NaCO2O4热电材料与其它制备方法得到的样品相比，具有致密的内部结构以及较好的热电性能。     

静电纺丝法制备尼龙-6/SiO2-TiO2杂化纳米纤维

采用静电纺丝法结合溶胶凝胶技术,制备了尼龙-6/SiO2-TiO2杂化纳米纤维。采用红外光谱（FT-IR）、X射线衍射（XRD）、UV-vis、热重分析（TG）和扫描电镜（SEM）等对杂化纳米纤维进行分析表征。结果表明,随着SiO2-TiO2溶胶的引入,电纺纤维的结晶度下降,耐热性能提升。尼龙-6电纺纤维的平均直径约为...     

纳米Ag~+-TiO_2/聚氯乙烯抗菌塑料制备及其性能

将纳米Ag+-TiO2用8%硅烷偶联剂(KH-560)进行表面改性,再与聚氯乙烯(PVC)树脂、增塑剂、润滑剂、稳定剂等混合,经熔融塑化,制得软质PVC抗菌塑料。考察了改性纳米Ag+-TiO2加入量对PVC抗菌塑料力学性能、加工流变性能和抗菌率的影响规律。研究表明:纳米Ag+-TiO2的加入可有效提高PVC塑料的力学性能和抗菌率,改善加工流变性能;当加入量为0.63%时,对大肠杆菌和金黄色葡萄球菌的抗菌率已超过90%;当Ag+-TiO2添加量为2.5%时,抗菌率超过99%,具有很好的抗菌效果。     

La3+掺杂TiO2纳米纤维的制备、表征与光催化性能

结合溶胶-凝胶法、静电纺丝技术和高温煅烧制备了La3+掺杂TiO2纳米纤维.采用扫描电子显微镜、X射线能谱仪、比表面积及孔隙分析仪、X射线衍射仪和紫外分光光度计对纳米纤维的形貌、晶型、表面和孔隙结构以及光催化性能进行了表征和测试.结果表明,La3+掺杂TiO2纳米纤维表面为多孔的纤维状结构.La3+掺杂明显改善了TiO2纳米纤维的表面孔隙结构,对TiO2纳米纤维的粒子生长有一定的抑制作用.光催化降解性能测试结果表明,当La3+掺杂量为0.04%(质量分数)时,TiO2纳米纤维的光催化性能最佳.     

SnO_2-TiO_2的制备及气敏性能研究

以SnCl4·5H2O和钛酸四丁脂为原料,采用Sol-Gel法制备SnO2-TiO2材料。运用XRD、TEM对SnO2-TiO2粉体的物相、形貌和结构进行表征。并测试其气敏性能。实验结果表明:SnO2-TiO2纳米粉体在3.5 V加热电压下对100 ppm乙醇的灵敏度为464.116。     

Ce掺杂ZnO光催化剂的制备及性能

采用共沉淀制备了稀土Ce掺杂ZnO光催化剂;利用X射线衍射（XRD）、扫描电子显微镜（SEM）等对光催化剂进行表征;考察了不同NaOH用量制备的催化剂光催化对亚甲基蓝脱色降解性能的影响。结果表明,ce的掺杂有利于抑制光生电子-空穴的复合,显著提高ZnO的光催化性;NaOH用量和Ce掺杂量对光催化剂的微观形貌和光催化活性有较大影响;制备过程中金属离子总量（Ce^3＋＋Zn^2＋）与OH-摩尔比为1：2．5,掺杂量为2％（摩尔分数）时,制备的催化剂主要微观形貌为具有层状微球结构,光催化性能良好。     

TiO_2/ZnO粒子的制备及其抗菌性能

采用溶胶凝胶法制备了TiO2/ZnO复合粒子,通过XRD、SEM对所制备粉体颗粒的物相组成以及表面形貌进行表征,通过最小抑菌浓度法(MIC)研究了不同掺杂量的TiO2/ZnO复合粒子的抗菌性能。结果表明,掺杂TiO2的ZnO粒子显示优良的抗菌活性,对金黄色葡萄球菌(Staphylococcusaureus)的MIC≤62.5μg·mL-1。当TiO2的掺入量为20%,所得到的ZnO粒子的抗菌性能最佳,对绿脓杆菌、大肠杆菌、枯草芽孢杆菌、金黄色葡萄球菌四种菌的抑菌性能均有显著提高,并对其机理做了初步探讨。     

Multifunctional ZnO/Nylon 6 nanofiber mats by an electrospinning–electrospraying hybrid process for use in protective applications

ZnO/Nylon 6 nanofiber mats were prepared by an electrospinning–electrospraying hybrid process in which ZnO nanoparticles were dispersed on the surface of Nylon 6 nanofibers without becoming completely embedded. The prepared ZnO/Nylon 6 nanofiber mats were evaluated for their abilities to kill bacteria or inhibit their growth and to catalytically detoxify chemicals. Results showed that these ZnO/Nylon 6 nanofiber mats had excellent antibacterial efficiency (99.99%) against both the Gram-negative Escherichia coli and Gram-positive Bacillus cereus bacteria. In addition, they exhibited good detoxifying efficiency (95%) against paraoxon, a simulant of highly toxic chemicals. ZnO/Nylon 6 nanofiber mats were also deposited onto nylon/cotton woven fabrics and the nanofiber mats did not significantly affect the moisture vapor transmission rates and air permeability values of the fabrics. Therefore, ZnO/Nylon 6 nanofiber mats prepared by the electrospinning–electrospraying hybrid process are promising material candidates for protective applications.     

Multifunctional ZnO/Nylon 6 nanofiber mats by an electrospinning–electrospraying hybrid process for use in protective applications

Abstract

ZnO/Nylon 6 nanofiber mats were prepared by an electrospinning–electrospraying hybrid process in which ZnO nanoparticles were dispersed on the surface of Nylon 6 nanofibers without becoming completely embedded. The prepared ZnO/Nylon 6 nanofiber mats were evaluated for their abilities to kill bacteria or inhibit their growth and to catalytically detoxify chemicals. Results showed that these ZnO/Nylon 6 nanofiber mats had excellent antibacterial efficiency (99.99%) against both the Gram-negative Escherichia coli and Gram-positive Bacillus cereus bacteria. In addition, they exhibited good detoxifying efficiency (95%) against paraoxon, a simulant of highly toxic chemicals. ZnO/Nylon 6 nanofiber mats were also deposited onto nylon/cotton woven fabrics and the nanofiber mats did not significantly affect the moisture vapor transmission rates and air permeability values of the fabrics. Therefore, ZnO/Nylon 6 nanofiber mats prepared by the electrospinning–electrospraying hybrid process are promising material candidates for protective applications.     

负载金属氧化物纳米夹心材料的制备及抗菌性能

采用静电纺丝法制备了负载有不同含量金属氧化物的纳米TiO2/聚已内酰胺(PA6)及纳米TiO2/PA6/Ag纤维,通过扫描电镜(SEM)对纤维进行了表征,纤维直径在50nm～100 nm之间;讨论了纤维平均直径与溶液黏度及电导率之间的关系;实验选用霉茵作为测试菌种,采用振荡瓶法对纤维进行抗茵性能测试,结果表明,抗茵纤维...     

纳米Ag-聚乙烯醇缩丁醛静电纺丝复合纳米纤维的制备及性能

采用静电纺丝技术制备纳米Ag-聚乙烯醇缩丁醛（PVB）复合纳米纤维,获得一类过滤性能和抗菌性能优异的空气过滤材料。采用TEM分析纳米Ag的形貌,采用SEM、FTIR和XRD等表征手段研究纳米Ag-PVB复合纳米纤维的微观形貌、化学结构以及结晶行为,并对其空气过滤性能、透气性能和抗菌性能进行了研究。结果表明：以乙醇为溶剂,当PVB含量为10wt%、纳米Ag含量为0.25wt%时,得到的纤维尺寸均一,平均直径为542.14 nm。性能测试结果表明,纺丝最佳时间为10 min,纳米Ag-PVB复合纳米纤维对PM2.5过滤效率为99.99%,过滤阻力为16 Pa,透气率为155.0 mm/s,并且对大肠杆菌表现出优异的抗菌性能,其抑菌率为95.52%。     

Photocatalytic and antibacterial properties of a TiO2/nylon-6 electrospun nanocomposite mat containing silver nanoparticles

Silver-impregnated TiO(2)/nylon-6 nanocomposite mats exhibit excellent characteristics as a filter media with good photocatalytic and antibacterial properties and durability for repeated use. Silver nanoparticles (NPs) were successfully embedded in electrospun TiO(2)/nylon-6 composite nanofibers through the photocatalytic reduction of silver nitrate solution under UV-light irradiation. TiO(2) NPs present in nylon-6 solution were able to cause the formation of a high aspect ratio spider-wave-like structure during electrospinning and facilitated the UV photoreduction of AgNO(3) to Ag. TEM images, UV-visible and XRD spectra confirmed that monodisperse Ag NPs (approximately 4 nm in size) were deposited selectively upon the TiO(2) NPs of the prepared nanocomposite mat. The antibacterial property of a TiO(2)/nylon-6 composite mat loaded with Ag NPs was tested against Escherichia coli, and the photoactive property was tested against methylene blue. All of the results showed that TiO(2)/nylon-6 nanocomposite mats loaded with Ag NPs are more effective than composite mats without Ag NPs. The prepared material has potential as an economically friendly photocatalyst and water filter media because it allows the NPs to be reused.     

Catalytic and antibacterial activities of green-synthesized silver nanoparticles on electrospun polystyrene nanofiber membranes using tea polyphenols

An efficient and environmentally friendly method has been developed to prepare Ag nanoparticles (AgNPs) coated tea polyphenols/polystyrene (Ag-TP/PS) nanofiber membrane, which combines electrospinning and in situ reduction of [Ag(NH₃)₂]⁺ using TP as the reductant and stabilizer. In this method, TP/Pluronic/PS nanofiber membranes are fabricated by electrospinning and then immersed in the aqueous solution of [Ag(NH₃)₂]⁺. While TP is being released from TP/Pluronic/PS nanofibers, the surface of TP/Pluronic/PS nanofibers could function as reactive sites for reduction of [Ag(NH₃)₂]⁺ without any extra reagents. XRD results indicate that AgNPs thus formed are in metallic form of Ag⁰. SEM images show that AgNPs can be densely and uniformly coated on the surface of TP/Pluronic/PS nanofibers. The as-prepared Ag-TP/PS nanofiber membranes exhibit excellent catalytic properties for the degradation of methylene blue. Furthermore, the effect of [Ag(NH₃)₂]⁺ concentration on the morphology and catalytic activity of the membrane is investigated. In addition, the antibacterial assays reveal that Ag-TP/PS nanofiber membrane possesses extraordinary antibacterial activity against both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli microorganisms. The free-standing membrane is flexible and easy to handle, which is promising for potential applications in catalysis, antibacterial agents and water remediation fields.     

Effective poly(ethylene glycol) methyl ether grafting technique onto Nylon 6 surface to achieve resistance against pathogenic bacteria <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> and <Emphasis Type="Italic">Pseudomonas aeruginosa</Emphasis>

Our study is focused on an efficient reduction of amide functional groups to secondary amine on Nylon 6 surface with borane–tetrahydrofuran (BH₃–THF) complex, followed by N-alkylation with benzyl chloride (C₆H₅CH₂Cl) which has been successfully used as a model system for further grafting of the reduced Nylon 6 surface by poly(ethylene glycol) methyl ether tosylate (Me-PEG-OTs). The amine-activated surface has been obtained by treatment of reduced Nylon 6 with n-butyllithium or tert-butyllithium in THF. Modified Nylon 6 has been found to be antibacterial particularly due to the presence of hydrophilic poly(ethylene glycol) methyl ether (H₃C-PEG) chains. The surface modifications were successfully characterized by various techniques. Water contact angle and free surface energy analyses indicated a significant change in the surface morphology. It was further supported by scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy and Raman spectroscopy. Finally, antibacterial tests were performed against two pathogenic bacterial strains Pseudomonas aeruginosa (CCM 3955) and Staphylococcus aureus (CCM 3953).     

静电喷涂制备抗菌夹心净化材料及其抗菌性能

为解决净化过滤用静电纺纤维在使用过程中容易受到微生物和残留有机物二次污染的问题,将电纺尼龙6(PA6)纤维、玻璃纤维与涂覆硅凝胶的工业滤布热压成型,采用静电喷涂技术将纳米TiO2沉积于净化材料的表面,制备出具有良好抗菌性能的夹心净化材料。扫描电镜(SEM)测试表明,喷涂的TiO2负载于纳米纤维的表面;X射线衍射(XRD)测试表明,喷涂后的纳米TiO2的晶型(锐钛型)未发生改变;抗菌测试结果表明,材料整体的杀菌率可达98.74%。     

Antibacterial polyacrylonitrile nanofibers produced by alkaline hydrolysis and chlorination

Antibacterial polyacrylonitrile (PAN) nanofibers were developed by alkaline hydrolysis and subsequent chlorination. It was shown that the hydrolyzed nanofibers could serve as an N-halamine precursor through chlorination of the amide groups obtained by partial hydrolysis of the nitrile groups. The hydrolysis conditions were optimized, so that sufficient chlorine for effective antibacterial activities could be obtained on the surfaces. The chemical and physical structural changes were well characterized with FTIR, TGA, DSC and SEM. It was found that even though the hydrolyzed nanofibers cyclized with ionic and free radical mechanisms, the chlorinated nanofibers cyclized with only free radical mechanism as evidenced by its higher onset of cyclization temperature. On the other hand, the hydrolysis and chlorination process significantly improved the mechanical properties of the nanofibers. Moreover, the chlorinated nanofibers showed potent antibacterial activities against S. aureus and E. coli with about 6 logs inactivation. The developed antibacterial PAN nanofibers possess great potential for use in various fields, medical industry in particular.     

载Ag/Cu纳米粒子多孔聚丙烯腈复合纤维膜的制备及其抑菌性

金属纳米粒子因其独特的物理化学性能,在催化、抑菌、水污染处理和生物医学等领域表现出巨大的应用前景。但是金属纳米粒子在制备和使用过程中容易发生团聚而影响其性能。因此,提高金属纳米粒子的稳定性,对提升其应用性能具有重大意义。本文在以聚丙烯腈(PAN)为基体,聚乙烯吡咯烷酮(PVP)为致孔剂,基于静电纺丝技术制得多孔聚丙烯腈纳米纤维(PPAN NFs)的基础上,通过浸渍沉积法分别制备出负载银纳米粒子(Ag NPs)复合纳米纤维(Ag-PPAN NFs)和负载铜纳米粒子(Cu NPs)复合纳米纤维(Cu-PPAN NFs)。在利用FESEM、EDS、XRD等方法对制备纤维膜的形貌和结构进行表征的基础上,通过抑菌圈法和FESEM观察经复合纳米纤维处理前后的细菌形貌来研究Ag-PPAN NFs和Cu-PPAN NFs对大肠杆菌、金黄色葡萄球菌和白色念球菌的抑菌性能。研究结果发现：PPAN NFs可有效解决Ag NPs和Cu NPs在制备和使用过程中易于聚集的问题,制得的复合纳米纤维对大肠杆菌、金黄色葡萄球菌和白色念球菌具有一定的抗菌活性,可成为一种新型的抗菌纤维材料。