Multi-walled carbon nanotube decorated CoS microspheres and their supercapacitive properties

In the present work, microspheres of CoS are synthesized by most adoptable hydrothermal method. The syn-thesized material is figured out by numerous characteristic techniques. Further, the prepared CoS material is used as electrode material for supercapacitor and high specific capacity of 112.62 mAh g-1 is obtained at 1 A g-1. Furthermore, the capacity of sole product is boosted by adding a small amount of multi-walled carbon nanotubes (MWCNTs) and improved specific capacity of 158 mAh g-1 is obtained from MWCNT/CoS at 1 A g-1. Owing to high specific capacity of composite, aqueous asymmetric supercapacitor (ASC) is designed by MWCNT/CoS as a positive electrode and activated carbon (AC) as a negative electrode. The high energy density of 31.6 W h kg-1 is obtained at the power density of 750 Wh kg-1 from MWCNT/CoS//AC. In addition, two parallel connected red color LEDs, kitchen timer and a motor fan are functionalized by two MWCNT/CoS//AC devices.

Automated summary

In this study, microspheres of CoS were synthesized by the commonly used hydrothermal method and characterized by various techniques. The prepared CoS material showed a high specific capacity of 112.62 mAh g-1 as electrode material for supercapacitors at 1 A g-1. By adding a small amount of multi-walled carbon nanotubes (MWCNTs), the specific capacity was further improved to 158 mAh g-1 at the same current density. Aqueous asymmetric supercapacitors (ASC) were designed using MWCNT/CoS as the positive electrode and activated carbon (AC) as the negative electrode, resulting in a high energy density of 31.6 W h kg-1 at a power density of 750 W h kg-1.