Two‐Dimensional Layered Metallic VSe<sub>2</sub>/SWCNTs/rGO Based Ternary Hybrid Materials for High Performance Energy Storage Applications
K. A. Sree Raj, Afsal S. Shajahan, Brahmananda Chakraborty, Chandra Sekhar Rout
Abstract
Abstract In this work, the ternary hybrid structure VSe 2 /SWCNTs/rGO is reported for supercapacitor applications. The ternary composite exhibits a high specific capacitance of 450 F g −1 in a symmetric cell configuration, with maximum energy density of 131.4 Wh kg −1 and power density of 27.49 kW kg −1 . The ternary hybrid also shows a cyclic stability of 91 % after 5000 cycles. Extensive density functional theory (DFT) simulations on the structure as well as on the electronic properties of the binary hybrid structure VSe 2 /SWCNTs and the ternary hybrid structure VSe 2 /SWCNTs/rGO have been carried out. Due to a synergic effect, there are enhanced density of states near the Fermi level and higher quantum capacitance for the hybrid ternary structure compared to VSe 2 /SWCNTs, leading to higher energy and power density for VSe 2 /SWCNTs/rGO, supporting our experimental observation. Computed diffusion energy barrier of electrolyte ions (K + ) predicts that ions move faster in the ternary structure, providing higher charge storage performance.