Energy storage performance of 2D MoS2 and carbon nanotube heterojunctions in symmetric and asymmetric configuration.

Excellent cyclic stability and fast charge/discharge capacity demonstrated by supercapacitors foster research interest into new electrode materials with 100% cycle life and high specific capacitance. We report an improvement in the electrochemical performance of MoS2/MWCNT nanohybrid and intensively explored its performance in symmetric and asymmetric supercapacitor assembly. The symmetric assembly of MoS2/MWCNT exhibits capacitance of around 274.63 F/g at 2 A/g with higher specific energy/power outputs (20.70 Whkg-1/1.49 kWkg-1) as compared to the supercapacitor based on pristine MoS2 (5.82 Whkg-1/1.07 kWkg-1). On the other hand, a unique all-carbon-based asymmetric supercapacitor assembled with MoS2/MWCNT and VSe2/MWCNT composite with K2SO4 as electrolyte delivers the highest energy density of 32.18 Whkg-1 at a power density of 1.121 kWkg-1 with exceptional cycling stability and excellent retention of about 98.43 % even after 5000 cycles. These outstanding results demonstrate the excellent electrochemical properties of both symmetric and asymmetric systems with high energy density and performance, which further enable them to be a potential candidate for supercapacitor applications.