植酸掺杂聚吡咯制备及电化学性能

Preparation and Electrochemical Performance of Phytic Acid Doped Polypyrrole

采用植酸作为掺杂剂,通过原位化学氧化聚合制备植酸掺杂聚吡咯,并利用扫描电子显微镜(SEM)、傅立叶变换红外光谱(FTIR)、X射线衍射(XRD)仪表征其表面形貌与结构,利用循环伏安(CV)、恒电流充放电(GCD)、交流阻抗(EIS)测试其电化学性能。FTIR结果表明,植酸与吡咯单体间的多重氢键及π-π相互作用有利于导电聚吡咯的成功聚合及有序生长。吡咯单体与植酸的比例最终影响掺杂聚吡咯的微观结构及性能。SEM与XRD结果表明,当吡咯∶植酸的物质的量之比为3∶1时,掺杂聚吡咯(Pyp3)表现为亚微米球相连的三维网络结构与良好的链规整性,这有利于其电化学性能的提高。利用GCD曲线计算其比电容可达265 F/g,与纯聚吡咯(153 F/g)相比有较大程度的提高,CV与EIS测试表明,与纯聚吡咯相比,Pyp3表现出更理想的超电容特性。

The phytic acid doped polypyrrole was prepared by in situ chemical oxidation polymerization method by using phytic acid as dopant.The surface morphology and structure were investigated by scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR)and X-ray diffraction(XRD)techniques.The electrochemical performances were studied by cyclic voltammetry(CV),galvanostatic charge discharge(GCD)and electrochemical impedance spectroscopy(EIS).FTIR results indicate that the multiple hydrogen bonds andπ-πinteractions between phytic acid and pyrrole monomer facilitate the successful polymerization and ordered growth of polypyrrole.The ratio of pyrrole to phytic acid influences the structure and property of the polypyrrole.The results of SEM and XRD demonstrate that as the ratio of pyrrole to phytic acid is 3∶1,doped polypyrrole(Pyp3)with ordered molecluar chains shows three dimensional network constructed by sub-microspheres,which facilitates the improvement of electrochemical performances.The specific capacitance of doped polypyrrole calculated from the GCD curves has been improved(265 F/g)compared with that of pristine polypyrrole(153 F/g).The CV and EIS testing results show that compared with pristine polypyrrole,Pyp3 exhibited more ideal supercapacitive performance.