Robust hierarchical three dimensional nickel cobalt tungstate-MXene nanocomposite for high performance symmetric coin cell supercapacitors. (15th December 2022)

• Record Type: Journal Article
• Authors: Vigneshwaran, J.; Narayan, R.L.; Ghosh, Dibyajyoti; Chakravarthy, V.; Jose, Sujin P.
• Is Part Of: Journal of energy storage. Volume 56:Part C(2022)
• Publication Date: 2022-12-15
• Subjects: Ni-CoWO4 -- MXene -- Supercapacitor -- Specific capacitance -- Symmetric supercapacitor; Energy storage -- Periodicals; Energy storage -- Research -- Periodicals; 621.3126
• DOI: 10.1016/j.est.2022.106102
• Languages: English
• ISSNs: 2352-152X

Abstract

Abstract: Design of rational electrode materials with hierarchically structured pseudocapacitive materials has been identified as a successful strategy for revamping the electrochemical characteristics of supercapacitors. However, the simultaneous assurance of strong electrical conductivity and higher specific capacitance via a simple and cost-effective synthesis protocol is of concern today. In this work, Ni-CoWO4 incorporated MXene nanocomposite has been successfully prepared by a facile hydrothermal process. The structure, morphology, stoichiometry, and chemical characterization of the prepared Ni-CoWO4, Ti3 C2 Tx, and Ni-CoWO4 @MXene nanocomposite were explored extensively. MXene demonstrated a layered 2D nanoscale structure whereas pure Ni-CoWO4 was composed of spherical nanoparticles. The composite Ni-CoWO4 @MXene revealed the morphology of spherical Ni-CoWO4 nanoparticles decorated on MXene sheets. Furthermore, a series of electrochemical characterizations illustrated the contribution of the delightful morphology of Ni-CoWO4 @MXene composite to excellent electrochemistry. The resultant Ni-CoWO4 @MXene electrode exhibited high specific capacitance of 582 F g −1 at 1 A g −1 and 93.5 % capacitance retention over the 10, 000 cycles., which is higher than that of the individual counterparts Ni-CoWO4 and MXene. The excellent electrochemical performance of Ni-CoWO4 @MXene is attributed to the synergistic interaction between Ni-CoWO4 nanoparticles and nanolayered MXene that may create new active sites that enhanced the charge transfer, charge/discharge kinetics and the electrical conductivity. Significantly, the unique Ni-CoWO4 @MXene supercapacitor prototype delivered a higher energy density of 85.7 Wh kg −1 and power density of 0.85 kW kg −1 establishing its superiority over other CoW based supercapacitors. A theoretical study was also performed to correlate the improved charge storage capacity of the prepared Ni-CoWO4 @MXene composite. Graphical abstract: Unlabelled Image Highlights: Simple and cost-effective synthesis of Ni-CoWO4 @MXene hierarchical nanostructure by hydrothermal route Ni-CoWO4 @MXene displays excellent phase purity and more surface-active sites. Introducing Ni-CoWO4 prevents the aggregation of MXene layers exhibiting enhanced electrochemical activity. The Ni-CoWO4 @MXene nanostructure exhibits superior capacitance of 587 F g −1 at a current density of 1A g −1 in a three-electrode cell. Ni-CoWO4 @MXene supercapacitor delivers a remarkable energy density of 85.7 Wh kg −1 at a power density of 0.85 kW kg −1 .