CoS engulfed ultra-thin S-doped g-CN and its enhanced electrochemical performance in hybrid asymmetric supercapacitor.

This work demonstrates a high-performance hybrid asymmetric supercapacitor (HASC) workable in very high current density of 30 A g with in-situ pyrolytic processed sulfur-doped graphitic carbon nitride/cobalt disulfide (S-gCN/CoS) materials and bio-derived carbon configuration and achievement of high electrochemical stability of 89% over 100,000 cycles with the coulombic efficiency of 99.6%. In the electrochemical studies, the S-gCN/CoS-II electrode showed a high specific capacity of 180 C g at 1 A g current density in the half-cell configuration. The HASC cell was fabricated using S-gCN/CoS-II material and orange peel derived activated carbon as a positive and negative electrode with a maximum operating cell potential of 1.6 V, respectively. The fabricated HASC delivered a high energy density of 26.7 Wh kg and power density of 19.8 kW kg in aqueous electrolyte. The prominent properties in specific capacity and cycling stability could be attributed to the CoS nanoparticles engulfed into the S-gCN framework which provides short transport distance of the ions, strong interfacial interaction, and improving structural stability of the S-gCN/CoS-II materials.