Higher energy density of MoSe2/polyaniline capsule nanospheres for enhanced performance supercapacitor

Abstract

It is very important to develop novel nanocomposites as electrode materials for supercapacitors (SCs). MoSe2 porous nanospheres were prepared by one-step hydrothermal method, and polyaniline (PANI) nanosheets were grown in situ to obtain MoSe2/PANI capsule nanospheres (CNs). By changing the amount of aniline, it was found that MoSe2/PANI-16 CNs had the best electrochemical performance, and a high specific capacitance of 753.2 F g−1 was obtained at a current density of 1 A g−1. In addition, the interface electron transport path was clarified that a C–Mo–Se bridge bonds may be formed for rapid electron transfer. The reaction kinetics was also explored. The large specific surface areas of MoSe2/PANI CNs provided more reactive sites, so that the contribution of pseudocapacitance was much larger than diffusion capacitance. The assembled MoSe2/PANI//activated carbon asymmetric supercapacitor has a energy density of 20.1 Wh kg−1 at a power density of 650 W kg−1. These results indicate that the MoSe2/PANI CNs are a promising electrode material.