Three-Dimensional Tubular MoS₂/PANI Hybrid Electrode for High Rate Performance Supercapacitor

Abstract

By using three-dimensional (3D) tubular molybdenum disulfide (MoS₂) as both an active material in electrochemical reaction and a framework to provide more paths for insertion and extraction of ions, PANI nanowire arrays with a diameter of 10–20 nm can be controllably grown on both the external and internal surface of 3D tubular MoS₂ by in situ oxidative polymerization of aniline monomers and 3D tubular MoS₂/PANI hybrid materials with different amounts of PANI are prepared. A controllable growth of PANI nanowire arrays on the tubular MoS₂ surface provides an opportunity to optimize the capacitive performance of the obtained electrodes. When the loading amount of PANI is 60%, the obtained MoS₂/PANI-60 hybrid electrode not only shows a high specific capacitance of 552 F/g at a current density of 0.5 A/g, but also gives excellent rate capability of 82% from 0.5 to 30 A/g. The remarkable rate performance can be mainly attributed to the architecture with synergistic effect between 3D tubular MoS₂ and PANI nanowire arrays. Moreover, the MoS₂/PANI-60 based symmetric supercapacitor also exhibits the excellent rate performance and good cycling stability. The specific capacitance based on the total mass of the two electrodes is 124 F/g at a current density of 1 A/g and 79% of its initial capacitance is remained after 6000 cycles. The 3D tubular structure provides a good and favorable method for improving the capacitance retention of PANI electrode