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1.
在没有外加掺杂剂的条件下,以FeCl3,Fe(NO3)3,Fe2(SO4)3,FePO4等多种铁盐为氧化剂,在水溶液中采用"无模板"的方法制备了具有较高电导率的聚苯胺纳米结构.铁盐是一种强酸弱碱盐,在水溶液中发生水解释放出质子,质子可以作为掺杂剂进入聚苯胺主链,因此,在苯胺的聚合过程中,铁盐同时起到氧化剂和掺杂剂的双重功能,进一步简化了导电聚苯胺纳米结构的合成条件,降低了反应成本.FTIR,UV-Vis,XRD等结构表征证实所得的纳米结构的聚苯胺均为掺杂态.试验发现,铁盐较低的氧化/还原电位使产物具有较小的直径和较高的电导率和结晶性.不同的对阴离子对聚苯胺产物的形貌有一定的影响,但对产物的结构和性能影响不大.铁盐与苯胺单体的比例对聚苯胺的形貌和电导率均有较大的影响.  相似文献   

2.
超疏水导电聚苯胺的界面聚合   总被引:1,自引:0,他引:1  
采用界面聚合和无模板法相结合的方法, 以具有疏水链的全氟癸二酸(PFSEA)为掺杂剂, 通过调节苯胺单体和FeCl3氧化剂的浓度实现了聚苯胺三维微/纳米结构形貌和尺寸的可控制备. 扫描电子显微镜测量结果显示, 聚苯胺是由一维纳米纤维自组装形成的三维微球结构; 红外吸收光谱和紫外-可见吸收光谱结果表明, 聚苯胺微球为掺杂态. 室温下, 该微/纳米结构聚苯胺微球的电导率为 9.6×10-3 S/cm, 表面水接触角为161.4°, 表现出半导体特性和超疏水性.  相似文献   

3.
自组装的氢氟酸掺杂的聚苯胺微/纳米管   总被引:2,自引:0,他引:2  
以氢氟酸为掺杂剂,采用无模板法制得了高电导率(10-2-10-1S/cm)聚苯胺微/纳米管(d=85-420nm).当[HF]/[An]=0.5时所得微/纳米管的形成机率高达100%.发现微/纳米管的直径和电导率均随[HF]/[An]比例的增加而增加.FTIR,UV-Vis,XRD结构表征证明所得的聚苯胺微/纳米管为掺杂态.  相似文献   

4.
采用石英晶体微天平(QCM)技术,探讨了以三氯化铁(FeCl3)和过硫酸铵(APS)为复合氧化剂,十二烷基苯磺酸(DBSA)为乳化剂和掺杂剂时,苯胺(An)的乳液聚合动力学行为;并通过对产物的循环伏安分析,初步优化了聚合反应条件.结果表明,An的乳液聚合反应对复合氧化剂、An以及DBSA分别为1,0.5和0.5级.各种条件下的循环伏安(CV)图都显示出PAn的三对氧化还原特征峰.当FeCl3与APS物质的量比为2∶1;氧化剂总量与苯胺的物质的量比为3∶1;DBSA浓度为0.05mol/L时,CV测试的峰电流和电导率最大.  相似文献   

5.
采用1-羧甲基-3-甲基咪唑氯化盐离子液体对钠化蒙脱土进行插层改性,然后用苯胺的盐酸溶液进行二次插层,以过硫酸铵为氧化剂,盐酸溶液为掺杂剂,使进入离子液体/蒙脱土(CMMIm/MMT)层间的苯胺(An)发生氧化聚合反应,制备了一种具有良好导电性的聚苯胺/离子液体/蒙脱土复合材料(PANI/CMMIm/MMT).用红外光谱、X-射线衍射,热重分析和DSC对样品进行了表征.结果表明当离子液体/蒙脱土用量为7.5%、盐酸浓度为1mol/L、过硫酸铵与苯胺的摩尔比为1∶1、0℃下反应6h时制备的PANI/CMMIm/MMT纳米复合材料电导率最高,达到了0.3S/cm,是相同条件下聚苯胺/钠化蒙脱土纳米复合材料电导率的2.5倍,聚苯胺的7.5倍.  相似文献   

6.
FeCl3为氧化剂合成了聚苯胺纳米纤维,纤维直径20~30 nm,并以此为载体对辣根过氧化物酶进行了固定化.SEM,FTIR,UV-Vis等结构表征证明辣根过氧化物酶HRP中的质子可作为掺杂剂与聚苯胺主链中的氮结合,酸根离子作为对阴离子依附于聚苯胺主链周围,实现了聚苯胺载体对生物酶的固定化.聚苯胺纳米纤维具有较大的比表面积,有利于增加酶的负载量,提高固定化酶活性.该方法简单,快速,载体材料无需活化.与游离酶相比,固定化酶对pH,高温的耐受性,不同温度下的热稳定性均有了明显的提高,在4℃条件下保存7周后固定化酶活性几乎没有损失,重复使用6次后仍可保持80%的酶活,说明纳米结构的聚苯胺是一种良好的载体,可实现生物酶的高效固定化.  相似文献   

7.
在十六烷基三甲基溴化铵(CTAB)存在下, 以盐酸为质子酸, 过硫酸铵为氧化剂, 制备了平均直径为115 nm、具有分叉结构的聚苯胺纳米纤维和平均直径为75 nm的卷曲聚苯胺纳米线, 两者的结构产率高达90%和100%, 电导率分别为1.6×10-2和9.3×10-2 S/cm. 研究发现, 聚苯胺的一维纳米结构受盐酸浓度和苯胺与CTAB摩尔比的协同影响. 用TEM, SEM和FTIR对产物的形貌和化学结构进行了表征. 利用pH监测反应并结合SEM结果研究了聚苯胺纳米线的形成过程, 结果表明, CTAB阳离子与过硫酸根形成的絮状物的诱导作用是聚苯胺纳米纤维和纳米线形成的关键因素.  相似文献   

8.
本文使用(NH_4)_2S_2O_8为氧化剂,用HCl、H_2SO_4和磷钨酸作为掺杂剂配制前驱体溶液,然后采用氧化还原法制备了聚苯胺电极材料。通过红外(FT-IR)、X射线衍射(XRD)、热重分析(TGA0)及扫描电子显微镜(SEM)对电极材料的结构和形貌进行表征,并利用四探针方法测定聚苯胺电极材料在控制氧化剂的量、酸的浓度和不同温度条件下的电导率。结果表明,磷钨酸掺杂聚苯胺(PANI)的结构和形貌优于HCl和H_2SO_4掺的PANI,过硫酸铵(APS)与苯胺(An)的摩尔比为1∶1、酸的浓度为2 mol·L~(-1)、合成温度为0℃的条件下,PANI具有高电导率,分别达到10.27、9.62和8.79S·cm~(-1)。  相似文献   

9.
以苯胺为单体, 过硫酸铵为氧化剂, 通过改变不同的掺杂剂, 采用"无模板"法合成了具有不同浸润性的聚苯胺微/纳米结构, 并得到超疏水聚苯胺微/纳米结构. 采用红外吸收光谱、 紫外-可见吸收光谱、 X射线衍射及扫描电镜对聚苯胺微/纳米结构及形貌进行了表征, 测定了聚苯胺微/纳米结构的接触角, 并通过Tafel极化曲线和电化学交流阻抗研究了不同疏水性的聚苯胺微/纳米结构在0.1 mol/L H2SO4溶液中对碳钢的腐蚀防护作用, 探讨了聚苯胺微/纳米结构的表面浸润性对腐蚀防护性能的影响. 研究结果表明, 随着聚苯胺微/纳米结构疏水性的增强, 对碳钢的腐蚀防护作用增强, 当掺杂剂为全氟辛酸时所制备的超水聚苯胺微/纳米结构表现出最佳的防腐蚀性能(η= 94.70%).  相似文献   

10.
基于碳纸电极电化学快速合成聚苯胺纳米纤维   总被引:2,自引:0,他引:2  
利用碳纸电极,采用循环伏安法、恒电流法和恒电位法等电化学聚合法快速合成了高氯酸掺杂聚苯胺纳米纤维.利用电子显微镜、红外光谱和四探针测定仪等对聚苯胺的微观形貌结构、掺杂度和电导率进行了研究.用循环伏安法对聚苯胺的电化学特征进行了分析.研究发现,3种方法合成的聚苯胺均为纳米纤维状结构,长度达3μm,直径为50~150 nm.其中,循环伏安法合成的聚苯胺纳米纤维的均一性和电导率均优于其它2种方法,其电导率高达5.97 S/cm.另外,聚苯胺合成速率顺序为恒电流法>循环伏安法>恒电位法,且恒电流法合成的聚苯胺纳米纤维电极材料的放电比容量最大(578 F/g),电容性能最好.  相似文献   

11.
Summary: Nanoscaled polyaniline (PANI) fibers with 17–30 nm in diameter were successfully prepared by oxidation polymerization using ferric hydrochloride (FeCl3 · 6H2O) as an oxidant in the presence of p‐toluenesulfonic acid (p‐TSA), β‐naphthalenesulfonic acid (β‐NSA), and camphorsulfonic acid (CSA) as the dopants. The resulting nanofibers show smaller diameter, higher crystallinity and conductivity (10−1 S · cm−1) compared with the nanofibers oxidized by ammonium persulfate (APS), which may be due to the lower oxidation/reduction potential of FeCl3.

SEM images of the PANI nanofibers prepared by oxidation polymerization using ferric hydrochloride as an oxidant.  相似文献   


12.
The polyaniline micro/nanostructure was prepared by a self‐assembly process with molybdic acid as dopants in the presence of ammonium persulfate as the oxidant. It was found that the morphology of PANI micro/nanostructure was affected by the concentration of the dopant, that is, the morphology of PANI changed from nanofibers to co‐existence of nanofibers and microspheres as the molar ratio of molybdic acid to aniline varied from 0.01 to 1.5. Under the same condition it was also found that the conductivity value of PANI enhanced from 4.58×10?3 S·cm?1 to 3.8×10?1 S·cm?1. The structure of PANI was characterized by FTIR and XRD which confirmed the presence of the molybdic acid in the PANI. The electrochemical characteristics of the PANI nanofibers were investigated by means of cyclic voltammetry. The morphology of PANI in the process of polymerization was characterized by SEM. It was found that when the molar ratio of molybdic acid to aniline was 0.3, the morphology of PANI was co‐existence of nanofibers and microspheres and the formation of microspheres was ahead of the nanofibers.  相似文献   

13.
Novel polypyrrole (PPy) micro/nanofibers were synthesized via a self-assembly process by using 4-hydroxy-3-[(4-sulfo-1-naphthalenyl) azo]-1-naphthalenesulfonic acid (Acid Red B) as dopant and ferric chloride (FeCl3) as oxidant. Experimental conditions, including the concentration of the dopant, reaction temperature and stirring state have been investigated for their influences on the morphology of the synthesized PPy micro/nanofibers. The products were characterized by scanning electron microscopy, transmission electron microscopy and Fourier-transform infrared spectroscopy. The formation mechanism of micro/nanofibers was studied. It is believed that the micelles formed by the dopant and pyrrole monomer act as templates during the synthesis process. Two functions of aggregation and synthesis are proposed in the reaction system simultaneously, and the morphologies of micro/nanofibers are the co-operations of these two functions. The maximum conductivity value of the PPy micro/nanofibers was 8.56 S cm?1  相似文献   

14.
以过硫酸铵或2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)为氧化剂,单一手性樟脑磺酸作为诱导酸及掺杂剂,在有机溶剂、水-有机溶剂和水溶剂体系中,采用四种不同方法分别进行了单一手性聚苯胺纳米纤维合成研究。通过扫描电子显微镜(SEM)、紫外可见光谱(UV-VIS)、X射线衍射(XRD)和圆二色谱(CD)等手段对自组装法、界面聚合法、低聚物辅助法与二次掺杂法等四种方法制备得到聚苯胺纳米纤维的形貌、结构及光学活性进行表征,对比分析后发现四种方法合成的掺杂态聚苯胺纳米纤维形貌、结构相似,但溶剂体系会影响最终产物的光学活性:水溶剂、有机溶剂体系中,得到的聚苯胺纳米纤维光学活性相反。  相似文献   

15.
This work demonstrated a facile route to the synthesis of polyaniline (PANI) nanofibers by polymerization of aniline using chloroaurate acid (HAuCl(4)) as the oxidant. The reduction of AuCl(4)(-) is accompanied by oxidative polymerization of aniline, leading to uniform PANI nanofibers with a diameter of 35 +/- 5 nm and aggregated gold nanoparticles which can precipitate from the liquid phase during the reaction. The resultant PANI nanofibers and gold particles were characterized by means of different techniques, such as UV-vis, FTIR spectroscopy, and scanning and transmission electron microscopy methods. It is found that the gold aggregates are capped with polyaniline, and the conductivity of the fibers is around 0.16 S/cm.  相似文献   

16.
采用乳液法, 以过硫酸铵(APS)和次氯酸钠(NaClO)为复合氧化剂合成导电聚苯胺(PANI). 考察了NaClO 的加入与否对PANI 微观形貌与电化学性能(循环伏安和电导率)的影响, 以及APS、乳化剂十二烷基苯磺酸钠(SDBS)和NaClO的用量对PANI 电化学性能的影响. 结果表明: NaClO 的加入对PANI 的微观取向结构具有重要的影响. 与采用单一APS 合成的PANI 相比, 复合氧化剂合成的PANI 具有较高的循环伏安峰电流以及更加优异的电导率(约为前者的2.6倍). 当苯胺(An)与APS 的物质的量比(nAn:nAPS )为8:7, An 与SDBS 的物质的量比(nAn:nSDBS )为10:4, NaClO 用量为5%(质量分数)时, PANI 的各项性能指标达到最好; 紫外可见光谱和红外光谱的表征结果表明, 采用复合氧化剂并未对PANI 的分子结构产生明显的影响.  相似文献   

17.
C60/polyaniline (PANI) nanocomposites have been synthesized by the oxidative polymerization of aniline with ammonium peroxydisulfate in the presence of C60 by using an interfacial reaction. When compared with the pure PANI nanofibers from the similar process, the diameter of the obtained C60/PANI nanofibers was increased because of the encapsulation of C60 into PANI during aniline polymerization, which resulted from the charge‐transfer interactions between C60 and aniline fragment in PANI. In addition, the resulting C60/PANI nanocomposites synthesized from the low initial C60/aniline molar ratio (less than 1:25) showed the homogenous morphology composed of fiber network structures, which has an electrical conductivity as high as 1.1 × 10?4 S/cm. However, the C60/PANI nanocomposites from the higher initial C60/aniline molar ratio (more than 1:15) showed the nonuniformly distributed morphology, and the electrical conductivity was decreased to 3.5 × 10?5 S/cm. Moreover, the C60/PANI nanocomposites from the interfacial reaction showed a higher value of electrical conductivity than the mechanically mixed C60/PANI blends with the same C60 content, because of the more evenly distributed microstructures. FTIR, UV–vis, and CV data confirmed the presence of C60 and the significant charge‐transfer interactions in the resultant nanocomposites, which was responsible for the morphology development of the C60/PANI and the variation of the electrical conductivity. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012  相似文献   

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