导电聚苯胺与磁性CoFe2O4纳米复合物的合成及其电磁性能

在利用HNO3处理CoFe2O4磁性纳米粒子使其表面离子化、分散性得到改善的基础上,采用苯胺在其表面原位聚合,制备了具有电磁功能的聚苯胺(PANI)/CoFe2O4纳米复合物.借助TEM、XRD、FT-IR、四探针电导率仪和VSM(振动样品磁强计)等分析手段研究了复合物的形貌、结构及其电磁性能.结果表明,CoFe2O4以25 nm左右的粒子分散于聚苯胺基体中,被其完全包覆,CoFe2O4与PANI之间存在化学键合作用;复合物同时具有电性能和磁性能,其导电牢随CoFe2O4含量增加而降低,饱和磁化强度随之升高,而矫顽力在所研究的范围内则先增大而后又减小,且均高于CoFe2O4的矫顽力.     

导电聚苯胺与磁性CoFe2O4纳米复合物的合成及其电磁性能

在利用HNO3处理CoFe2O4磁性纳米粒子使其表面离子化、分散性得到改善的基础上, 采用苯胺在其表面原位聚合, 制备了具有电磁功能的聚苯胺(PANI)/CoFe2O4纳米复合物. 借助TEM、XRD、FT-IR、四探针电导率仪和VSM(振动样品磁强计)等分析手段研究了复合物的形貌、结构及其电磁性能. 结果表明, CoFe2O4以25 nm左右的粒子分散于聚苯胺基体中, 被其完全包覆, CoFe2O4与PANI之间存在化学键合作用; 复合物同时具有电性能和磁性能, 其导电率随CoFe2O4含量增加而降低, 饱和磁化强度随之升高, 而矫顽力在所研究的范围内则先增大而后又减小, 且均高于CoFe2O4的矫顽力.     

单分散P(St-BA-AN)/PANI核壳结构复合微球的制备与电性能

以苯乙烯(St)、丙烯酸丁酯(BA)和丙烯腈(AN)为单体, 采用乳液聚合的方法制备出单分散苯乙烯-丙烯酸丁酯-丙烯腈三元共聚物[P(St-BA-AN)]种子微球, 再在该种子微球表面包覆聚苯胺(PANI), 制得P(St-BA-AN)/PANI核壳结构复合微球. 采用扫描电镜(SEM)、透射电镜(TEM)、傅里叶变换红外透射光谱(FTIR)和漫反射光谱等测试手段对所制备的种子微球和复合微球的形态、结构和形成机理进行了研究, 并用四探针法测定了核壳结构复合物的导电性. 研究结果表明, 通过改变种子乳液共聚物的组成和加入苯胺的量及氧化剂的量等条件可调控复合微球的电导率. 与P(St-BA)/PANI核壳结构复合微球相比, 在核组成中引入了氰基的P(St-BA-AN)/PANI核壳结构复合微球的电导率明显提高, 当加入苯胺的量为P(St-BA-AN)种子微球与苯胺单体总质量分数的40%时, 其电导率可达到0.71 S/cm. 红外光谱结果证实了P(St-BA-AN)种子微球中的氰基和壳层中聚苯胺的胺基之间存在某种相互作用, 导致核壳结构复合物电导率的提高.     

聚苯胺-LiNi铁氧体复合纳米微粒的原位合成及其键合机制

通过原位溶液聚合法制备了聚苯胺-LiNi铁氧体(LiNi_0.5Fe₂O₄)复合纳米微粒, 用X射线衍射(XRD)、红外光谱(FTIR)、拉曼光谱(Raman)、紫外-可见光谱(UV-Vis)、透射电子显微镜(TEM)以及振动样品磁强计(VSM)等技术表征了复合物的结构、形貌和磁性能. 结果表明, 复合物在室温外加磁场下表现出亚铁磁性物质具有的磁滞现象, 铁氧体颗粒对苯胺的聚合起到了核的作用; 复合物中铁氧体与聚苯胺之间存在着比较明显的键合作用, 探讨了铁氧体与聚合物分子链之间的键合机制.     

聚苯胺/碳化钨导电复合材料的合成

以苯胺和过硫酸胺为原料,采用原位聚合方法合成了聚苯胺/碳化钨(PANI/WC)导电复合材料。研究了反应体系中碳化钨的含量对复合材料电导率的影响,确定了较佳的聚合条件,并且通过FT-IR、XRD、XPS和DSC-TGA等手段对复合材料的结构和性能进行了表征和分析。结果表明:碳化钨(WC)的加入提高了聚苯胺的电子导电性能,复合材料中聚苯胺组分为无定型,WC的晶型在反应前后并未发生变化,复合材料的热稳定性好并且质子化程度更高。     

钛酸盐纳米管-聚苯胺-金纳米颗粒复合材料的制备及其生物电化学性能

采用水热法制备出钛酸盐纳米管(TNTs),然后使用氧化聚合法将苯胺聚合到TNTs表面生成聚苯胺(PANI),最终将金纳米粒子还原到PANI表面制备出三元复合纳米材料(TNTs-PANI-GNPs).其中PANI作为交联剂链接起TNTs和GNPs形成稳定和结合紧密的三元复合纳米材料,不同的光谱和显微图像技术证实了三元复合纳米材料的成功合成.我们将辣根过氧化物酶(HRP)与三元复合纳米材料充分混合均匀后涂抹于玻碳电极表面,伏安实验结果证明HRP已实现在TNTs-PANI和TNTs-PANI-GNPs修饰电极上的直接电子转移,而且后者相较于前者对过氧化氢的催化还原电流增强了大约74.9%.TNTs-PANI-GNPs复合纳米材料修饰的生物传感器的优越电化学性能主要归因于复合材料中TNTs、PANI和GNPs三者之间的协同作用,将优点最大化,将缺点最小化.     

导电聚苯胺与磁性CoFe2O4纳米复合物的制备与表征

在利用HNO3酸化处理CoFe2O4磁性纳米粒子使其表面离子化、分散性得到改善的基础上, 采用原位聚合法制备了具有电磁功能的聚苯胺/CoFe2O4 (PANI/CoFe2O4)纳米复合物. 借助TEM, XRD, FT-IR, TG, 四探针电导率仪、VSM(振动样品磁强计)等分析手段研究了复合物的形貌、结构、热稳定性及电磁性能. 结果表明, 处理过的CoFe2O4磁性纳米粒子可形成分散均匀的PANI/CoFe2O4纳米复合物, CoFe2O4以25 nm左右的粒子分散于聚苯胺基体中; PANI与CoFe2O4之间存在化学键合作用, 正是这种作用使复合物热稳定性得以提高; 复合物同时具有导电性和磁性能, 且随CoFe2O4含量变化而变化.     

聚甲基丙烯酸甲酯接枝多壁碳纳米管的制备及表征

采用原位聚合的方法,分别在本体及超临界CO2介质中将聚甲基丙烯酸甲酯(PMMA)接枝到多壁碳纳米管(MWNTs)表面,通过GPC、拉曼光谱、TGA等手段对样品进行表征.聚合产物的GPC结果表明,体系中的PMMA存在游离和接枝两种状态;拉曼光谱中峰的红移以及D峰与G峰强度比值的增加证明PMMA与MWNTs之间存在化学键作用;TGA结果表明PMMA在本体和超临界CO2中的接枝率分别为39 %和27%.     

水溶液中碳纳米管的表面增强拉曼光谱研究

合成了碳纳米管和金纳米颗粒的复合物, 测量了水溶液相中复合物的表面增强拉曼光谱, 结果表明, 碳纳米管的巯基化修饰可以提高碳纳米管与金纳米颗粒复合的效率, 随着金纳米颗粒负载量的增加, 碳纳米管的拉曼信号逐渐增强. 加入己二胺分子可以减小金纳米颗粒之间的距离使表面增强效应更显著, 碳纳米管的拉曼光谱得到进一步的增强. 还可进一步在复合体系中加入对巯基苯胺和罗丹明B等小分子拉曼探针, 利用金纳米颗粒的表面增强效应, 这种多元复合体系有望作为多通道拉曼成像探针材料.     

有机化学接枝-电化学沉积聚合制备CNTs/PANI纳米复合材料

通过有机化学合成法先在碳纳米管表面接枝上苯胺单体,然后在不锈钢电极表面在硫酸溶液中采用循环伏安法电化学沉积聚合制得碳纳米管/聚苯胺(CNTs/PANI)纳米复合材料.扫描电子显微镜和傅立叶变换红外光谱表征所得材料的微观结构和基团,循环伏安和恒流充放电测试用于考察所得CNTs/PANI纳米复合材料的电化学性能.所得结果与...     

Pseudo Capacitive Studies of Polyaniline-Carbon Nanotube Composites as Electrode Material for Supercapacitor

This study describes the formation of composites of polyaniline (PANI)-Carbon Nanotube (CNT) using in situ chemical oxidative polymerization of the monomer aniline. The PANI-CNT composites were characterized by FTIR and UV-Visible spectroscopy and XRD method. The surface morphology of the composites was characterized by scanning electron microscopy (SEM). Pseudo-capacitive behavior of deposited PANI over the surface of CNT was investigated by means of cyclic voltammetry. The composite was mixed with activated carbon for making the electrode. The specific capacitance of the prepared electrode was tested by means of a half cell test. The PANI-CNT composite with 0.02 M aniline in initial polymerization solution had the thinnest layer and highest specific capacitance of 597.82 F/g in 1 M H₂SO_4.     

Synthesis of stable aqueous dispersion of graphene/polyaniline composite mediated by polystyrene sulfonic acid

A facile method of producing stable aqueous dispersion of graphene/polyaniline (PANI) composite is described, which involves the in situ polymerization of aniline on the surface of graphene with the aid of polystyrene sulfonic acid (PSS). The prepared aqueous graphene/PANI composite dispersion was very stable and no aggregation or precipitation was observed for several weeks. The excellent aqueous dispersibility and stability of the graphene/PANI composite is attributed to the cooperative interactions of π stacking interaction between PSS, PANI, and the graphene basal planes, and the electrostatic repulsions between negatively charged PSS bound on graphene/PANI composite. Fourier transform‐infrared spectrometry (FTIR), ultraviolet‐visible spectra (UV–vis), and Raman spectra confirmed the interaction of PANI and graphene in the composite, which effectively delocalize the electrons. In addition, the composite showed three orders of magnitude of conductivity increase compared with pure PANI. This new approach is simple, fast, and straightforward, representing a significant improvement in the processing of graphene/PANI composites. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

不同质子酸掺杂对银/聚苯胺纳米复合材料结构和导电性的影响

利用紫外光作为辅助条件,在反胶束体系中采用一步双原位法合成了硝酸(HNO3)、对甲基苯磺酸(TSA)和5-磺基水杨酸(SSA)掺杂的银/聚苯胺(Ag/PANI)纳米复合材料.通过对复合材料进行红外光谱(FTIR)、紫外光谱(UV-Vis)、扫描电镜(SEM)、X射线衍射(XRD)和导电性能的测试,研究了不同质子酸对Ag/PANI纳米复合材料结构、形貌和导电性能的影响.测试结果表明,3种酸掺杂制备的Ag/PANI纳米复合材料均为聚苯胺包覆银粒子的核-壳结构.不同的质子酸掺杂会对Ag/PANI纳米复合材料的电性能有重要影响.在3种酸掺杂的复合材料中,TSA掺杂的复合材料的电导率最佳,为215.14 S·cm-1.     

Fabrication of polyaniline with hierarchical structures in alkaline solution

Nanosheet- or nanorod-based microspheres and nanorod-based microrods of polyaniline (PANI) with hierarchical structures were successfully prepared by oxidation polymerization of aniline in alkaline solution. Temperature was found to have important influence on the morphology of PANI hierarchical structures and their building blocks. The concentration of alkali (NaOH) could be used to guide the morphological evolution of PANI, from leaf-like structures to nanosheet-based particles, and to nanorod-based microspheres and nanorod-based microrods with increasing concentration of NaOH in synthesis. The chemical structures of product were characterized by FTIR, UV-vis spectra and XRD, and its solubility was also studied in this report.     

Conductive composite of polyaniline and tungsten carbide

Conductive polyaniline/tungsten carbide (PANI/TC) composite was synthesized via polymerization of the aniline monomer by (NH₄)₂S₂O₈/H₂SO₄ oxidant system in the presence of an aqueous suspension of TC. The structure, thermal stability and conductivity of PANI/TC composite were studied and the results were also compared with the pure PANI. The results showed that there was a strong interaction between the TC particles and PANI molecular chains. The crystalline structure of TC remained undisturbed upon with interaction with PANI chains. The thermal stability of PANI/TC composite was better than that of pure PANI. The direct current conductivity values of PANI/TC composite decreased slowly as the temperature increased from 25 to 165°C and PANI/TC composite exhibited significantly higher conductivity than the pure PANI.     

Thermal stability of several polyaniline/rare earth oxide composites (I): polyaniline/CeO<Subscript>2</Subscript> composites

Polyaniline (PANI)/CeO₂ composites were prepared by adding CeO₂ powder into the polymerization reaction mixture of aniline. Fourier transform infrared spectra (FTIR) and X-ray diffraction (XRD) were used to characterize the composites. Thermogravimetry (TG) and derivative thermogravimetry (DTG) were used to study the thermal stability of the composites. IR and XRD results show that interaction exists between PANI and CeO₂. This interaction maybe is hydrogen bonding action between the hydroxyl groups on the surface of the CeO₂ and the imine groups in the PANI molecular chains. TG–DTG analysis indicates that the thermal stability of the composites is higher than that of the pure PANI. The improvement in the thermal stability of the composites is attributed to the interaction between PANI and CeO₂, which restricts the thermal motion of PANI chains and shields the degradation of PANI in the composites.     

Conductive Nanocomposites Based on Cellulose Nanofibrils Coated with Polyaniline-DBSA Via In Situ Polymerization

Summary: Cellulose nanofibrils (CNF) were extracted by acid hydrolysis from cotton microfibrils and nanocomposites with polyaniline doped with dodecyl benzenesulphonic acid (PANI-DBSA) were obtained by in situ polymerization of aniline onto CNF. The ratios between DBSA to aniline and aniline to oxidant were varied in situ and the nanocomposites characterized by four probe DC electrical conductivity, ultraviolet-visible-near infrared (UV-Vis - NIR) and Fourier-transform infrared (FTIR) spectroscopies and X-ray diffraction (XRD). FTIR and UV-Vis/NIR characterization confirmed the polymerization of PANI onto CNF surfaces. Electrical conductivity of about 10⁻¹ S/cm was achieved for the composites; conductivity was mostly independent of DBSA/aniline (between 2 and 4) and aniline/oxidant (between 1 and 5) molar ratios. X-ray patterns of the samples showed crystalline peaks characteristic of cellulose I for CNF samples, and a mixture of both characteristic peaks of PANI and CNF for the nanocomposites. Field emission scanning electron microscopy (FESEM) characterization corroborated the abovementioned results showing that PANI coated the surface of the nanofibrils.     

WC/CNT纳米复合材料制备及其对甲醇氧化的电催化性能

采用表面修饰技术将碳纳米管(CNT)表面羧基化, 通过羧基将钨离子基团修饰到碳纳米管的外表面, 再通过原位还原碳化技术, 将钨离子基团还原成碳化钨(WC)纳米微粒, 制备出WC/CNT纳米复合材料. 采用FTIR、XRD、SEM、HRTEM和N2吸附等分析测试手段对样品的形貌、晶相组成和微观结构特征进行了表征. FTIR和N2吸附结果表明, 硝化后, 在碳纳米管表面羧基化的同时比表面积增加; XRD结果表明, WC/CNT样品由碳纳米管、WC以及非化学计量比的氧化钨组成; SEM和HRTEM结果表明, WC纳米颗粒均匀地分散于碳纳米管的外表面,并与碳纳米管构成了复合材料. 采用循环伏安法测试了样品在碱性条件下对甲醇氧化的电催化性能, 结果表明, 复合材料对甲醇氧化的电催性能明显强于WC 和碳纳米管, 并在实验结果的基础上探讨了复合材料催化性能提高的原因.