The role of carbon nanotubes in enhanced charge storage performance of VSe(2): experimental and theoretical insight from DFT simulations

Herein, we report the hybrid structure of metallic VSe(2) and multi-walled carbon nanotube (MWCNT) based hybrid materials for high performance energy storage and high power operation applications. The dominance of capacitive energy storage performance behaviour of VSe(2)/MWCNT hybrids is observed. A symmetric supercapacitor cell device fabricated using VSe(2)/80 mg MWCNT delivered a high energy density of 46.66 W h kg(−1) and a maximum power density of 14.4 kW kg(−1) with a stable cyclic operation of 87% after 5000 cycles in an aqueous electrolyte. Using density functional theory calculations we have presented structural and electronic properties of the hybrid VSe(2)/MWCNT structure. Enhanced states near the Fermi level and higher quantum capacitance for the hybrid structure contribute towards higher energy and power density for the nanotube/VSe(2).