Preparation Of Carbon/Polyaniline Electrode Materials For Supercapacitor Application And Its Electrochemical Performance

Supercapacitor, as an important energy storage device, has been paid abundant attention due to its high power density, high columbic efficiency, and excellent cycling stability. In this work, we have developed a new composite material combining both EDLC materials（Hierarchical porous carbon, HPC） and pseudocapacitor material（Polyaniline, PANI） to maximize the synergistic effect. This as-prepared material has demonstrated both high capacitance and good long cycle life.Firstly, the pure PANI was firstly fabricated by a in-situ solution polymerization method with different protonic acids（such as HCl, H₂SO₄, H₃PO₄）, using ammonium persulfate as oxidant. It can be found that, PANI-HCl demenstrate prefect electrochemical preformance. The electrochemical performance of PANI-HCl was carried out in 1 M H₂SO₄, exhibits relatively high specific capacitance value of 390 F g-1 at a current density of 0.5 Ag^-1, good rate performance(69 % capacity retention from 0.5 to 5Ag^-1), but a poor cycling performance(39 % retention upon 1000 charge/discharge cycles at 5 Ag^-1).Subsequently, a polyaniline coated hierarchical porous carbon（HPC） composite（PANI@HPC） is developed through a vapor deposition polymerization（VDP） method.The as synthesized composite is applied as the supercapacitor electrode material, and presents a high specific capacitance of 531 F g-1 at current density of 0.5 Ag^-1 and superior cycling stability of 96.1 %(after 10,000 charge-discharge cycles at current density of 10 Ag^-1). Furthermore, an aqueous symmetric supercapacitor device based on PANI@HPC is fabricated, exhibiting maximum specific capacitance value of 124.2 F g-1 at 0.1 Ag^-1 with good rate performance(76.6 % retention, varying from 0.1 Ag^-1 to 2 Ag^-1) and a high specific energy of 17.3 Whkg^-1 at power density of 49.8 Wkg^-1.