Ex-situ synthesis of MnS nanoparticles imbedded with carbon nanotubes as a high-performance electrode material for supercapacitors

Abstract

Electrochemical supercapacitors (ESCs), having high power density as well as great cycling stability, have been accepted as the most effective means of the electrochemical energy storage system. Transition metal sulfides (TMSs) have shown a lot of interest in supercapacitors because of their high theoretical capacitance, excellent conductivity, conservation friendliness, cost-effective, quick charge storage operations, and high power density as well as long cycling stability. Among various TMSs, manganese sulfide (MnS), has recently been attracted to supercapacitor applications as a better electrode material. Unfortunately, poor rate capability, fast capacitance fading, and low energy density due to sluggish electrochemical reactions during the fast charge storage process are the main obstacles to its commercial application. To address these stubborn issues like low rate because of poor conductivity, and low cycle efficiency, fabrication of composites by incorporating carbon nanotubes (CNT) could be an effective strategy. In this study, through the hydrothermal method, MnS was synthesized and mixed mechanically with CNT to prepare the MnS/CNT. While assessing the supercapacitive performance, MnS electrodes delivered only 966 F g−1 at 10 Ag−1, whereas at same current density the MnS/CNT composite offered a much higher specific capacitance of 1298.0 F g−1 with outstanding capacitance retention even after 4000 cycles.