In-situ design of porous vanadium nitride@carbon nanobelts: A promising material for high-performance asymmetric supercapacitors

Abstract

Vanadium nitride and porous carbon are emerging as new class of electrodes and are extensively being explored as high-performance supercapacitor (SC) materials for their interesting properties. In this study, vanadium nitride@porous carbon (VN@C) nanostructured hybrid material for SCs is synthesized utilizing in-situ, one-pot chemical synthesis technique. The VN@C hybrid nanostructure has achieved very high capacitance by utilizing the combinations of electric double layer capacitive (EDLC) properties of porous carbon and pseudocapacitive characteristics of VN nanoparticles (VN NPs) and delivered maximum specific capacitance of 1850 C g−1 @10 A g−1 current density, with an excellent rate capability of 98% over 2000 cycles. Exploring the excellent electrochemical characteristics of VN@C, an asymmetric supercapacitor (ASC) cell is constructed with activated carbon (AC) as negative and VN@C as positive electrode. Remarkably, the as-constructed VN@C//AC ASC device achieves an excellent capacitance of 102 F g−1 at 1 A g−1 with the energy and power densities of 17–30 Wh kg−1 and 701–5608 W kg−1, respectively, over the current density range of 1–8 A g−1. Our facile preparation of highly porous carbon nanobelt-vanadium nitride composite along with high-energy storage properties pave the way for the development of various carbon–metal nitride hybrid nanostructures for promising energy storage applications.