In-situ electropolymerized polyaniline nanoparticles grown on longan shell-derived porous carbon for high-performance supercapacitor electrode

In this study, novel in-situ electropolymerized polyaniline nanoparticles grown on longan shell-derived porous carbon were prepared for high-performance supercapacitor electrode, which exhibited a high specific capacitance of 486F·g−1 at the current density of 0.5 A·g−1 in 1 M H2SO4 electrolyte via a three-electrode test. Further, the asymmetric supercapacitor was constructed with the energy density as high as 47.3 Wh·kg−1 at the power density of 800 W·kg−1 and excellent durability, in which the retention rate of specific capacitance was still as high as 85 % over 10,000 cycles. The excellent electrochemical performance of the as-prepared composite electrode material can be attributed to the large specific surface area of longan shell-derived porous carbon with honeycomb-like morphology up to 1613.2 m2·g−1, as well as the homogeneous electropolymerization of polyaniline nanoparticles grown on porous carbon, resulting in efficient pseudocapacitive charge storage. Noteworthily, natural longan shell as a renewable carbon source can be suitable for the preparation of high-quality and low-cost porous carbon to significantly improve the performance of supercapacitor electrode, which also provides a feasible pathway for high-value utilization of waste biomass resources.