聚苯胺/二氧化锰/氧化石墨烯复合电极的制备及性能

Preparation and Properties of Polyaniline/Manganese Dioxide/Graphene Oxide Composite Cathode

采用电化学的方法,以氧化石墨纸为支撑一步法制备导电聚苯胺(PANI)/二氧化锰(MnO2)/氧化石墨烯(GO)复合材料;采用四因素三水平正交设计,研究制备复合电极的最佳工艺;采用扫描电镜、X射线衍射、红外光谱和电化学测试对复合电极进行表征和电化学性能进行研究。结果表明,石墨纸经100 min氧化,在硫酸锰浓度0.3 mol/L、磺基水杨酸(SSA)浓度为30 g/L的硫酸-苯胺溶液里以聚合电流密度为18 mA/cm^2制备出最佳的PANI/MnO2/GO复合电极,以0.2 A/g恒流放电,其比能量可达336 Wh/kg。复合电极的微观形貌为三维网状结构,具有大的比表面积和孔体积;二氧化锰、聚苯胺和石墨纸形成复合良好的三维网状结构,不仅有利于降低极化,还能使电解液与电极充分接触,提高活性物质的利用率,其电化学性能远远优于PANI压制电极和氯化银电极。

Polyaniline/manganese dioxide/graphene oxide(PANI/MnO2/GO)composites(PMGO)based on graphite support paper,which could be used as cathode in sea-water battery,were prepared by one-step electrochemical method.The optimum condition of preparation of PMGO composite cathode was confirmed by orthogonal design.The XRD,SEM,FT-IR and electrochemical methods were used to characterize and study the composites.The results show that the optimum condition is as follows:graphite paper is oxidized for 100 min,and the PANI/MnO2/GO composite electrode was polymerized in H2SO4-aniline solution with the MnSO4 concentration of 0.3 mol/L,sulfosalicylic acid(SSA)concentration of 30 g/L,and polymerization current density of 18 mA/cm^2.The specific energy of PANI cathode is up to 336 mWh/g with the 0.2 A/g constant current discharge.The PMGO cathode with a larger specific surface area and pore volume than that of the PANI pressed cathode,represents a 3 D framework morphology,which is beneficial for reducing the polarization and increasing the interface and the usage of active substance.The electrode performance of PMGO is much better than that of PANI pressed cathode and AgCl cathode.