Preparation And Application Of The Fourth-period Transition Metal Ion Doping And NiO Composite Polyaniline Electrode In Supercapacitor

Electrode materials are a key factor that influenc the performance of supercapacitors.Among them,conductive polymer electrode materials have become one of the most promising supercapacitor materials due to its simple synthesis,low cost,high chemical stability and unique doping/de-doping.In this paper,the fourth period transition metal ion doped polyaniline（PANI）composite electrode was synthesized by different methods,and the paper compares its structure,morphology and electrochemical properties.In addition,the paper synthesizes the polyaniline/nickel oxide（PANI/NiO）composite electrode,its structure and morphology were characterized,also its electrochemical properties were studied.The main contents are as follows:（1）PANI-Ni²⁺,PANI-Co²⁺,PANI-Mn²⁺and PANI-Cu²⁺composite electrodes were synthesized by electrochemical cyclic voltammetry with different transition metal ions(M²⁺=Ni²⁺,Co²⁺,Mn²⁺,Cu²⁺)as dopants.The structure and morphology were characterized by FTIR and SEM,and the electrochemical properties of the composite electrodes such as CV,EIS and GCD were tested.Through a series of electrochemical performance tests,it was found that the specific capacitance of Ni²⁺,Co²⁺,Mn²⁺,Cu²⁺doped PANI electrodes increased to 340,247,199 and 114 F·g^-1,respectively,compared with pure PANI(112 F·g^-1).Then Ni²⁺doped PANI electrodes with different concentrations（C=0.05 M,0.1 M,0.2 M,0.4 M）were synthesized.Under the same conditions,it was found that 0.2 M Ni²⁺doped PANI electrodes had the best capacitance performance.（2）PANI electrodes doped with different transition metal ions(M²⁺=Ni²⁺,Co²⁺,Mn²⁺,Cu²⁺)were synthesized by chemical methods,and the structure and morphology were characterized.The electrochemical properties of PANI-Ni²⁺,PANI-Co²⁺,PANI-Mn²⁺and PANI-Cu²⁺composite electrodes were tested by CV,EIS and GCD.The results showed that the electrochemical properties of PANI composite electrodes doped with different transition metal ions were improved to some extent.Among them,Ni²⁺doped PANI electrodes had a maximum specific capacitance of 339 F·g^-1.（3）The PANI/NiO composite electrode without adhesives was synthesized by hydrothermal method and deposition method.The structure and morphology of the composite electrode were characterized by FTIR,SEM and XRD.A series of electrochemical performance tests on the composite electrode showed that the specific capacitance retention of the PANI/NiO electrode was about 77%after 1000 cycles.