循环伏安法制备聚苯胺/活性炭超级电容器膜电极

采用电化学循环伏安法,在柔性石墨纸基底材料上合成了聚苯胺/活性炭(PANI/AC)复合薄膜。 通过SEM观察了不同扫描圈数下复合薄膜的表面形貌,通过循环伏安(CV)、交流阻抗(EIS)、恒流充放电等电化学测试方法,研究了聚苯胺/活性炭复合电极的电性能。由SEM图谱可知,不同扫描圈数下,聚苯胺/活性炭的形态也有所不同,电化学测试结果表明,以柔性石墨纸为基底材料,扫描圈数在3圈时,不仅比容量较高,达504 F·g^-1,而且循环稳定性较好,经2000次循环后,容量衰减仅为初始容量的14%。     

草酸电还原制备乙醇酸

用循环伏安法确定了草酸可以还原为乙醇酸,证明了从草酸研制乙醇酸的可行性。工艺采用以铅电极作阴极材料的阳离子交换膜电解槽,电解草酸制备乙醇酸,并以电流密度、电量、温度和电解液的流速作了四因素四水平的正交实验,得出最佳工艺条件为电流密度1400A/m2,电量1 7F/mol,温度40℃,电解液流速0 15m/s,产率达88%以上。     

Electrolytic removal of hexavalent chromium from aqueous solutions

The removal of hexavalent chromium from a synthetic solution and from an industrial sample by electrolysis using stainless steel plate and titanium mesh cathodes is studied. It is found that the process proceeds in two steps: (1) electroreduction of hexavalent chromium to trivalent chromium in highly acidic medium and (2) electrochemical precipitation of trivalent chromium in an alkaline medium. A comparative study of electroreduction, electrochemical reduction and chemical reduction of hexavalent chromium is carried out and the electroreduction process is shown to be a clean technique. It is concluded that, in the absence of addition of any chemical as reducing agent, the Cr(III) solution formed on the reduction of Cr(VI) can be recycled in other industrial processes. Copyright © 2003 Society of Chemical Industry     

聚苯胺/聚乙烯复合电极的制备及性能测定

以低密度聚乙烯（PE）为基体材料,乙烯-醋酸乙烯共聚物（EVA）为增韧剂,聚苯胺（PAn）和炭黑（CB）为导电添加剂制备复合电极板,探讨了原料配比对物理力学性能、电学性能的影响。结果表明,原料配比PE∶EVA∶CB=75%∶5%∶20%时,电极的电阻最小,但是其韧性不佳;当原料配比PE∶EVA∶（CB＋PAn）=85%∶5%∶10%时,复合电极板具有最好的韧性能。     

Reduction of hexavalent chromium by polypyrrole deposited on different carbon substrates

Pollution due to toxic hexavalent chromium has reached dangerous levels in some parts of the world, especially in Third World countries. This work focuses on the reduction of Cr(vi) ions in aqueous media by polypyrrole deposits on porous, high area three-dimensional carbon electrodes. Since many properties of deposited polymers are known to depend on the method of synthesis we performed the electropolymerization of pyrrole either at varying potential scan rates or at constant potential on different high area carbon materials. The deposits thus obtained were then put in contact with acidic hexavalent chromium solutions; high reduction yields were obtained (up to 80%). In addition, the possibility of repeating this cycle was studied as well as the wear resistance of these deposits. Finally, the morphology of the deposits was monitored at different stages of the process by scanning electron microscopy.     

Synthesis and characterization of a composite of polyaniline and carbon black

A method is described for obtaining a composite of polyaniline and carbon black by cycling the potential of a Pt electrode in a solution containing aniline and carbon black suspension. The solution may also contain sodium dodecyl sulphate (SDS) as additive. It is shown that the rate of polymerization is enhanced by the presence of both carbon black and SDS by a factor of 5. The composite was characterized by cyclic voltammetry, scanning electron microscopy and capacity measurements.     

Reduction of hexavalent chromium using polyaniline films. Effect of film thickness, potential and flow velocity on the reaction rate and polymer stability

Reduction of very toxic hexavalent chromium (Cr(VI)) to its trivalent state (Cr(III)) is necessary to facilitate the treatment of wastewater by precipitation or adsorption. The present study proposes the use of thin films of polyaniline on a conducting substrate for this purpose. The reduction rate of hexavalent chromium and the degree of degradation of the polyaniline film were studied as a function of the solution flow velocity, applied potential and film thickness. The reduction rate was significantly affected by the flow velocity, while the film thickness was observed to have little effect. The potential had no effect on the reduction rate within the range studied. The current efficiency was 100% in all experiments and no significant degradation of polyaniline was observed.     

活性炭处理含铬废水的方法

活性炭具有优良的吸队性和还原性，已广泛用于废水处理工业，阐述了活性炭处理含铬废水的基本原理，采用吸附－还原联用处理含铬废水，介绍了其工艺流程、特点及处理过程中的注意事项。实践证明，经处理的废水中六价铬含量达国家排放标准。     

Removal of chromium from waste water using polyaniline

One of the suitable methods for removing heavy metals from waste water is using surface adsorption process. In this article, the preparation of polyaniline and its composites as adsorbents are discussed and the capability of separating chromium from industrial waste water is studied. The results were compared with anthracite and cation exchangers such as purolite‐302 and amberjet. The observations indicated that the purolite and amberjet have the most chromium removal percentage. Also the role of polyaniline and its composite as adsorbents were studied. The results show that the percentage of chromium removal has increased in polyaniline/poly(vinyl alcohol) composite. Furthermore, the adsorption percentage is related to the surface morphology, type of adsorbents, and their weight ratios. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1964–1967, 2007     

Reaction rate and electrochemical stability of conducting polymer films used for the reduction of hexavalent chromium

The reduction of toxic hexavalent chromium to its trivalent state at conducting polymers films was studied. The process is based on the capacity of conducting polymers to spontaneously donate electrons to the Cr(VI) species. Electrodes of polyaniline and polypyrrole, deposited as films on reticulated vitreous carbon (RVC), were prepared. The process of Cr(VI) reduction was studied under open and closed circuit conditions. It was observed that polyaniline was only suitable for use only under closed circuit conditions, whereas polypyrrole did not perform well under either open or closed circuit conditions. The electrocatalytic power of polyaniline for Cr(VI) reduction was demonstrated when the reaction rates for bare RVC and RVC/PANI were compared.     

Conductive hybrid film from polyaniline and polyurethane-silica

In order to improve the mechanical performance and water resistance of water-borne conducting polyaniline film, conducting polyaniline/polyurethane-silica hybrid film was prepared in aqueous solution employing silanol-terminated polyurethane and methyltriethoxysilane as sol-gel precursors. The hybrid film showed surface resistivity of 10⁸ Ω even though the conducting polyaniline loading was only 10 wt% (or 1.5 wt% of polyaniline), and the mechanical performance as well as water resistance was significantly improved, making it suitable for antistatic application. Therefore, a practical route to water-borne processing of conducting polyaniline is disclosed.     

Fabrication of honeycomb-patterned polyaniline composite films using chemically modified polyaniline nanoparticles

A novel polyaniline composite was prepared by in situ ring-opening polymerization of ε-caprolactone in the presence of chemically modified polyaniline nanoparticles (PANI-NPs) using Sn(Oct)₂ as an initiator, which exhibited a high solubility in organic solvent to enable the fabrication of stable honeycomb-patterned thin films by casting the PANI composite solutions under humid conditions. The chemically modified PANI-NPs were produced from the polymerization of aniline in the cationic surfactant of cetyl trimethyl ammonium bromide (CTAB). The polyaniline composites were characterized via Fourier transform infrared, ultraviolet–visible spectroscopy, X-ray diffraction, transmission electron microscopy, and thermogravimetry. The analyses indicated that the PANI-NPs were well incorporated in the poly(ε-caprolactone) (PCL) backbone. The patterned PANI composite films showed high DC conductivity up to 10⁻² S/cm, which can be useful in applications such as bio-sensing, bio-nanotechnology, biological science, and medicine.     

聚苯胺薄膜在不同质子酸溶液中的生长

在H2SO4、HCl、HNO3和H3PO4质子酸水溶液中采用原位聚合法在石英基片上制备了聚苯胺薄膜.通过对薄膜试样进行红外光谱(FT-IR)、紫外光谱、扫描电镜(SEM)、导电性能的测试研究不同种类质子酸对聚苯胺薄膜厚度及导电性能的影响.实验结果表明,试样的掺杂程度和薄膜分子链共轭长度是提高试样导电性能的重要因素,质子酸的氧化性对薄膜生长和导电性能也会产生影响.     

腐蚀保护层中六价铬含量分析

六价铬是一种致癌物质,它在汽车和电子工业中的应用受到欧盟的严格限制。目前,在腐蚀保护层中测定Cr(VI)的分析方法已经颁布实施。本文介绍了可用于上述两个行业的Cr(VI)检测标准──EN 15205和IEC 62321,并讨论了两者的差别。     

Magnetite/graphene/polyaniline composite for removal of aqueous hexavalent chromium

Here, we report the synthesis of Fe₃O₄/G/PANI composite containing magnetite nanoparticles (Fe₃O₄), graphene sheets (G), and polyaniline (PANI) via chemical route for removal of toxic Cr (VI) from water. TEM image shows the formation of uniformly distributed magnetite nanoparticles on graphene/PANI composite. HRTEM images shows the formation of crystalline magnetite nanoparticles showing lattice fringes with inter‐planner distance 0.21 nm. The magnetic measurement shows magnetization 22 emu/g and ferromagnetic property of the adsorbent. The equilibrium adsorptions were well‐described by the Langmuir isotherm model and shows maximum adsorption capacity 153.54 mg/g at pH 6.5 and temperature 30 °C. The kinetics data well fitted by pseudo‐second‐order model and around 86% Cr (VI) removal completed within 20 min. The Cr (VI) removal capacitive decreases with increase in pH and ionic strength. The adsorbent shows leaching of iron nanoparticles at pH 1 whereas stable in solution having pH 2 and more. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44002.     

Microstructural behaviors of polyaniline/CB Composites by SAXS

Polyaniline doped with dodecylbenzene sulfonic acid and conductive carbon black (PAn.DBSA/CB) hybrid materials have been prepared by in situ polymerization. The electrical resistivity of the PAn/CB was measured as a function of CB. The minimum resistivity was noticed for the composites with 25 wt % of CB as compared to other systems. Small angle x‐ray diffraction data was used to characterize the molecular arrangements of these composites. The refinement parameters such as periodicity (L), phase lengths (<Y> and <Z>), phase ratio (<Y>/<Z>), and probability distribution of phases [γ_Z (crystalline), γ_Y (amorphous)] for PAn, CB, and PAn/CB composites have been measured by SAXS data. It was observed that there is decrease in the crystallinity with increase in CB content in the composites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

预处理玻碳电极线性扫描伏安法测定槲皮素的研究

运用循环伏安法、线性扫描伏安法等测试技术研究了槲皮素在预处理玻碳电极上的电化学行为,建立了一种直接测定槲皮素的电化学分析方法。结果表明,与裸玻碳电极相比,预处理玻碳电极能显著提高槲皮素的氧化峰电流。在优化的实验条件下,氧化峰电流与槲皮素浓度在1.0×10-7～2.0×10-5mol/L范围内呈良好的线性关系,最低检测限为6.2×10-8mol/L。该方法简便、快捷、准确、灵敏度高。本法用于芦丁水解产物槲皮素的测定,效果良好。     

聚苯胺导电复合膜研究进展

将力学性能好的基质与聚苯胺相复合制备聚苯胺导电复合膜是对聚苯胺改性的重要方法之一。介绍了聚苯胺导电复合膜的主要制备方法,包括机械共混法、溶液共混法、电化学合成法、现场乳液聚合法、现场原位聚合法和现场吸附聚合法。综述了聚苯胺导电复合膜在防静电材料、电磁屏蔽材料、敏感元器件、电致变色材料、可充电电池、分子级电路等方面的应用。     

不同酸掺杂聚苯胺的电化学聚合及性能

采用循环伏安（CV）法在镀金PET膜上分别聚合了硫酸（H2SO4）、十二烷基苯磺酸（DBSA）、硫酸-十二烷基苯磺酸掺杂的聚苯胺（PANI）膜,对比研究了掺杂酸种类对PANI结构和性能的影响。结果表明,SO42?、DBSA?可以随聚合过程进入PANI分子链;H2SO4掺杂的PANI具有较高的电导率,但是在空气中的稳定性较差;大分子的DBSA使PANI优先产生单螺旋的纤维,提高了PANI在平行分子链方向上的结晶度和在空气中的稳定性;相对于单一酸掺杂,复合酸掺杂的PANI在酸溶液中电扫描表现出优良的循环伏安特性,在保持较高电导率的同时,提高了PANI在空气中的稳定性。     

硝基化合物的电还原方法

概述了硝基化合物还原的主要方法,介绍了在不同介质体系下不同种类的硝基化合物的电还原进展,并重点归纳出不同介质体系中电还原的优缺点。