电聚合固定化介体催化强化2,6-二硝基甲苯生物还原

难生物降解的水溶性氧化还原介体会随出水而流失,造成二次污染.采用活性炭毡(ACF)电极上电聚合吡咯单体掺杂蒽醌二磺酸盐技术制备的固定化氧化还原介体,AQDS/PPy/ACF,考察了其作为一种新型固态介体催化2,6-二硝基甲苯(2,6-DNT)生物还原的可行性.结果表明,基体材料对聚吡咯复合材料的表面形貌特性影响很大,在铂片上形成的聚吡咯呈菜花状,而在ACF上则呈现微球状;AQDS/PPy/ACF对2,6-DNT具有较强的生物催化活性和催化稳定性;它的加入可使2,6-DNT的生物还原速率提高近4倍,一级降解动力学常数达到0.0345h-1;在该反应体系中,2,6-DNT首先被还原为中间产物2-氨基-6-硝基甲苯(2-A-6-NT),后者再被还原为终产物2,6-二氨基甲苯(2,6-DAT).     

聚吡咯膜电极对茜素红的电催化作用

用循环伏安法研究了电化学聚合的聚吡咯（ＰＰｙ）膜电极对茜素红电极反应的电催化活性。在聚吡咯膜电极上，茜素红的阳极氧化电流比在铂电极上增加数倍。相应的阴极过程也较铂电极显出一定的催化活性。茜素红在铂电极上和ＰＰｙ膜电极上都显示了吸附现象。在ＰＰｙ膜电极上用电位扫描法载入一定的铂微粒时，载铂微粒的ＰＰｙ膜电极上茜素红的电催化电流进一步增加．在较高的电位和扫描速率下更为明显；但载入的铂微粒过多时，则使电流峰变平坦。     

Effect of electrolytes on electrochemical properties of graphene sheet covered with polypyrrole thin layer

Graphene sheet (GS) was successfully covered with a polypyrrole (PPy) thin layer through in situ chemical oxidative polymerization of pyrrole monomers in aqueous solution by using GS as a support material and ferric trichloride as an oxidant. The resulting nanocomposite was studied by field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR) and electrical measurements, including cyclic voltammetry (CV), galvanostatic charge/discharge experiment (GCD), and impedance spectroscopy (EIS). It has been found that the nanocomposite exhibited a typically curved and layer–like structure, and conformational change of PPy chains occurred due to the π–π stacking interaction between the graphitic structures in GS and aromatic rings of the PPy chains. More attention was paid to the effect of electrolytes on electrochemical properties of the nanocomposites, as expected, electrochemical performance was dependent on the nature of the electrolyte, and the neutral electrolytes containing alkali metal ions were found to be very suitable for GS/PPy nanocomposite. Compared with the pure PPy, the nanocomposite possessed larger specific capacitance and lower internal impedance, indicating that the nanocomposite can be a promising candidate as electrode material for supercapacitors.     

聚吡咯纳米线的合成及形貌表征

采用阳离子表面活性剂十六烷基三甲基溴化铵（CTAB）为软模板,2-丙烯酰胺基-2-甲基丙磺酸（AMPSA）为掺杂剂,在15℃左右,以过硫酸铵为氧化剂,引发吡咯（Py）氧化聚合制备了形貌规整的聚吡咯（PPy）纳米线,其直径约为20～40nm。系统地研究了反应体系中CTAB、AMPSA和吡咯等试剂的浓度对PPy形貌的影响,并初步探讨了PPy纳米线的形成机理。结果表明,试剂浓度的变化对所得PPy形貌影响较小。此研究为制备规整的PPy纳米线开拓了一种快速稳定的方法。     

双胶束模板合成高结晶度的片状结构聚吡咯

在阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)和阴离子表面活性剂十二烷基硫酸钠(SDS)存在的条件下,以过硫酸铵(APS)为氧化剂,15℃下氧化聚合吡咯得到了具有高结晶度的规整片状结构聚吡咯。研究了体系中表面活性剂浓度对所得聚吡咯形貌的影响,发现当CTAB,SDS,Py单体浓度分别为0.01,0.01,0.03mol/L时所得片状结构产物较规整。初步探讨了具有高结晶度片状结构聚吡咯的形成机理:两种表面活性剂形成CTAB-SDS双胶束,Py单体以其为模板氧化聚合得到了片状结构的聚吡咯。     

聚丙烯纤维膜为基底的聚吡咯合成及其电容性能研究

通过对吡咯蒸汽的化学氧化,在聚丙烯纤维表面原位生成了聚吡咯及其与氧化镍的复合物.用XRD、SEM对样品进行了结构表征,用四探针法测试了样品的电导率.用循环伏安、恒电流充放电和交流阻抗法研究了复合材料的电化学电容性能.结果表明:复合膜的形貌、电导率和其用作电容的性能受到反应条件、聚吡咯度其复合物含量的影响;掺入氧化物有利于改善电容器的充放电性能.     

银/聚吡咯/二氧化钛复合纳米粒的制备与结构表征

以钛酸四丁酯、硝酸银和吡咯为原料采用溶胶-凝胶法制备了银/聚吡咯/二氧化钛(Ag/PPy/TiO2)复合纳米粒,考察了PPy单体用量、原料配比等因素对制备复合纳米粒的影响。运用扫描电镜(SEM)、透射电镜(TEM)、红外光谱仪(FTIR)等测试方法对复合纳米粒进行了表征。结果表明,Ag/PPy/TiO2复合纳米粒具有棒状的核壳结构,聚吡咯包覆在Ag和TiO2纳米粒子的表面。     

聚吡咯H+选择电极的性能研究

采用电化学合成方法制备了聚吡咯H^ 选择电极．利用红外光谱探讨了掺杂不同阴离子聚吡咯膜的结构特征;探讨了聚吡咯电极在pH缓冲溶液中的阻抗谱特征及pH响应机理．比较了各种电极的能斯特斜率、转换系数和温度效应的差异,实验结果表明,未掺杂的聚吡咯(Pt／PPy)对H^ 响应的能斯特斜率、转换系数较掺杂T5O^-离子[Pt／PPy(T5O^-)]和HCO3^-离子[Pt／PPy(HCO3^-)]的要大．     

聚吡咯膜电极的静止电位

作者分别以玻璃炭和铂片为基础电极,在电解质的乙腈溶液中,由吡咯电聚合成不同厚度的聚吡咯膜电极(PPy),并测定了电解质浓度、溶液水含量、pH值的变化、氧化性盐的存在,以及环境气氛对PPy的静止电位的影响。     

利用可再生模板制备聚吡咯纳/微米管

以小分子2-蒽-9-基亚甲基一丙二腈(AYM)自组装的纳/微米线为模板,气液相聚合制备出聚吡咯(PPy)与AYM复合材料(PPy/AYM),经CH_2Cl_2溶剂脱除AYM后制得管状PPy.红外分析(IR-ATR)显示复合材料主要表现出PPy的特征峰.扫描电镜(sEM)和透射电镜(TEM)显示当吡咯(Py)单体与AYM两者之间用量摩尔比维持合理水平时,可以获得长度几十甚至上百个微米,直径1μm左右甚至更小的管状PPy.热失重(TGA)显示所得PPy纳/微米管与本体PPy具有相似的热失重行为,但电导率低一个数量级.脱除AYM的CH_2Cl_2溶液在减压蒸馏后仍旧可以得到AYM,回收率为93%,可重复使用.     

聚苯胺(PAn)和聚吡咯(PPy)膜电极对Hg(Ⅰ),Sn(Ⅱ)氧化的电催化行为

聚苯胺(PAn)和聚吡咯(PPy)膜电极对Hg(Ⅰ),Sn(Ⅱ)的氧化的电催化作用以循环伏安法(CV)进行了研究.在0.3mol·dm~(-3)HNO_3中PAn膜电极对Hg(Ⅰ)的氧化在0.445V处有一个非常尖的氧化峰,其峰电流I_(pa)的值为同样条件下Hg(Ⅰ)在光滑裸铂电极上峰电流值的5倍以上.PPy膜电极对Hg(Ⅰ)的电催化氧化有相似的结果,在0.49V处有一个尖峰,这是Hg(Ⅰ)在PPy上的氧化峰,I_(pa)值为在裸铂电极上的数倍.这些结果都说明PAn和PPy对Hg(Ⅰ)的氧化有明显的电催化作用.与此相似,PAn,PPy膜对Sn(Ⅱ)的氧化有类似的效果.PAn与PPy对Hg(Ⅰ)和Sn(Ⅱ)的氧化,其峰电流I_(pa)与扫描速率v的平方根成直线关系,这说明Hg_2~(2+)和Sn~(2+)离子在这两种导电聚合物膜电极上的电极过程受膜内扩散控制.     

熔盐电解法制备PPy/3R-MoS2纳米片及对U(VI)吸附效果的研究

为提高水溶液中铀的分离能力,本文采用熔盐电解法制备3R-MoS₂纳米片,并用聚吡咯(PPy)对其进行改性,采用水热法合成了复合纳米吸附剂(PPy/3R-MoS₂)。在700 K温度下,以Mo丝为阴极,C棒为阳极,调节恒电流电位仪电流大小为2 A,对KCl–NaCl–Na₂MoO₄–KSCN熔盐体系进行恒电流电解1 h。待电解产物冷却至室温后,用去离子水洗涤过滤,在60℃下真空干燥2 h,得到3R-MoS₂纳米片。将制备的3R-MoS₂纳米片(1.0 g)分散在50 mL含PPy(2.34 mL)的去离子水中,加入10 mL(1 mol/L) FeCl₃溶液,在10℃下放置24 h。将反应后的样品在5000 r/min下离心20 min,用无水乙醇和去离子水分散两次后,在70°C下真空干燥2 h,得到PPy/3R-MoS₂纳米片。通过批次吸附实验,探究了制备的纳米片在不同pH、反应时间、U(VI)初始浓度和温度条件下对U(VI)的吸附效果,并利用SEM、HRTEM、XRD、FTIR和XPS对其进行表征。在不同实验条件下,与3R-MoS₂和聚吡咯(PPy)相比,复合纳米吸附剂(PPy/3R-MoS₂)对U(VI)的吸附能力增强。当U(VI)初始浓度为80–100 mg/L时, PPy、3R-MoS₂和PPy/3R-MoS₂的吸附均达到平衡,最大吸附量分别为30.9、58.7和200.4 mg/g。XPS和FTIR分析阐明了其吸附机理:1) 带负电的PPy/3R-MoS₂纳米片通过静电吸引捕获UO₂2+);2) 裸露的C,N,Mo,S原子通过配位作用与U(VI)络合;3) 络合物中的Mo将吸附的U(VI)部分还原为U(IV),再生了吸附位点,从而连续吸附U(VI)。具有高吸附容量和化学稳定性的PPy/3R-MoS₂复合材料的设计为放射性核素的去除提供了新的方向。     

The Gas Sensitivity of Polypyrrole Film Fabricated by in Situ Polymerization

1 Results Polypyrrole (PPy) is a typical conducting polymer with high conductivity and good stability,and has been widely used for detection of gases including ammonia and nitroxide[1].However the reversiblity and selectivity of the response to these gases are always not satisfying.In the paper,conductive PPy film was deposited on the interdigital electrode modified by one bilayer of poly(diallyldimethylammonium chloride) and poly(sodium styrenesulfonate),by in-situ polymerization with FeCl3 as oxidizin...     

溶剂对导电聚吡咯防腐蚀性能的影响

采用循环伏安法分别在含吡咯+NaClO4的乙腈中和水中,在不锈钢表面制备了聚吡咯(PPy)膜.用扫描电子显微镜观察了PPy膜的表面形貌,用四探针法测量了PPy膜的电导率,用动电位极化曲线和电化学阻抗谱研究了在1mol/L H2SO4中PPy膜对不锈钢的防腐蚀性能.结果表明,在两种溶剂中制备的PPy膜都由球状粒子组成,但在水中制备的PPy膜结节较多.在乙腈中制备的PPy的电导率和对不锈钢的防护性能都显著高于在水中制备的PPy.由于乙腈的给电子性较水的小,与吡咯聚合中间体的作用小,链反应较难终止,使得PPy聚合链共轭度长,膜的缺陷少,电导率大,防腐性能好.     

Binder-free heterostructure(g-C_3N_4/PPy) based thin film on semi-flexible nickel foam via hybrid spray technique for energy storage application

A semi-flexible binder-free graphitic carbon nitride(g-C_3N_4) intercalated polypyrrole(PPy) nanocomposite thin film was prepared via hybrid electrospray technique. A homogeneous thin film was achieved by the controlled spray process. A deposited thin film illustrated the amorphous nature of composite with high surface purity and good chemical composition. The surface analysis confirmed the smoother surface with well-defined distinct phases of g-C_3N_4 and PPy matrix in the composite thin film. The electrochemical studies exhibited that a maximum areal capacity of the thin film was achieved to be 289.6 mF/cm~2 at a current density of 0.4 mA/cm~2,which is higher than that of pristine PPy(194.8 mF/cm~2). The heterostructure electrode illustrated that the life cycles of 99% could be up to 10,000 cycles with low resistance due to the synergetic effect of g-C_3N_4 and PPy matrix with strong material adhesion(hybrid spray process) on the surface. A binder-free heterostructure thin film will play a significant role in the energy storage application.     

Carbon-nitrogen/graphene composite as metal-free electrocatalyst for the oxygen reduction reaction

Sheet-like carbon-nitrogen (CNx)/graphene composites with a high content of nitrogen (x≤0.15) was prepared by the carbonization of polypyrrole (PPy)/reduced-graphene-oxide (rGO) composite at 600-800°C. We used rGO instead of graphene oxide (GO) sheets as a template and a substrate to immobilize PPy since the PPy/GO composite agglomerates easily because of the dehydration of excess oxygen-containing groups on the GO sheets during the drying process. The dried PPy/rGO intermediate and its derived CNx/graphene products retain their high dispersion and loose-powder features. The as-prepared CNx/graphene composites have a total nitrogen content of about 10 at% and their nitrogen state is mainly of pyridinic and graphitic type. CNx/graphene composites exhibit excellent performance for the oxygen reduction reaction (ORR) in terms of electrocatalytic activity, stability and immunity towards methanol crossover and CO poisoning, suggesting their potential as metal-free electrocatalysts for the ORR.     

聚吡咯纳米小球的光电探测性能研究

通过微乳液法制备尺寸均一的聚吡咯(PPy)纳米小球,并通过溶液沉积法在氧化铟锡玻璃表面制备聚吡咯纳米小球的光电化学池工作电极,以研究其光电探测响应性能。利用扫描电子显微镜(SEM),透射电子显微镜(TEM),傅里叶变换红外光谱仪(FT-IR),紫外-可见吸收光谱仪(UV-Vis),拉曼光谱仪 (Raman)及X-射线粉末衍射仪(XRD),表征及探讨所制备的聚吡咯纳米小球的形貌、尺寸及其物理和化学性能;采用光电化学池的方法对所制备的聚吡咯纳米小球进行光电探测,通过调节测试参数,系统研究聚吡咯纳米小球的光电探测响应行为。结果表明：制备的PPy纳米小球尺寸均一,缺陷少,光电探测能力强(904 nA/cm2),响应速度快(0.6 s)并赋有高的环境稳定性。研究结果可为开拓高性能基于导电聚合物的光电探测器提供理论基础。     

聚吡咯/海藻酸锰小球的性能研究

将海藻酸钠水溶液滴加到Mn Cl2水溶液中凝固成海藻酸锰小球。海藻酸锰小球吸附吡咯单体,在酸性KMn O4溶液中使吡咯单体氧化聚合成聚吡咯(PPy),得到聚吡咯/海藻酸锰复合小球(MPM)。用红外光谱仪、扫描电子显微镜和电化学工作站表征了复合小球的结构、形貌和电化学性能。结果表明:直径为200⁵00 nm的PPy微球聚集在海藻酸锰小球的表面。随着海藻酸钠在Mn Cl2水溶液的凝固时间增加,MPM的PPy含量偏低,复合小球的电容值减小。这种具有导电和生物相容性的MPM将在新型电极材料领域得到应用。     

Fabrication and Characterization of Polypyrrole/Polyurethane/Polyamide/Polyamide Yarn-Based Strain Sensor

Yarn-based strain sensors serve as essential elements for wearable electronics in the applications of personal health monitoring, motion detection, and smart garments. In the paper, a yarn-based strain sensor was created by coating conductive polymer, polypyrrole(PPy), onto a double covered elastic yarn, i.e., polyurethane/polyamide/polyamide(PU/PA/PA) yarn. Surface morphology of the yarn-based strain sensors demonstrates that the PPy conductive particles are evenly distributed on the surface of the PA multi-filaments as well as immersed into the PU core. Cyclic tensile test is conducted to characterize the electro-mechanical performance of the yarn-based strain sensor. The mechanical hysteresis of the sensor is low, which mainly comes from the geometrical change of the PA filaments around the PU core. However, the electro-mechanical hysteresis of the sensor is large mainly due to the unrecoverable cracks of the PPy layers on the PU core.     

超顺磁中空碳胶囊的合成及其载药性能研究

利用聚苯乙烯-丙烯酸（PSA）共聚物胶粒为模板,采用控制沉降和原位聚合的方法首先合成PSA@Fe2O4／聚砒咯（PPy）复合核壳粒子;将去核后得到的Fe3O4／PPy空心胶囊进一步热解炭化,制备了单分散Fe3O4／Carbon空心胶囊．样品物相及结构经X射线衍射仪（XRD）、透射电子显微镜（TEM）和扫描电子显微镜（SEM）表征．超导量子干涉仪（SQUID）测定结果显示,碳胶囊样品呈超顺磁性．N2气吸附测试结果显示磁性碳胶囊的比表面积BET为98m^2／g．以Fe3O4／Carbon磁性空心胶囊对抗癌药物阿霉素进行负载后,体外模拟释放实验结果显示胶囊具有良好的药物缓释性能．