Crystalline flower-like nickel cobaltite nanosheets coated with amorphous titanium nitride layer as binder-free electrodes for supercapacitor application. (1st January 2023)

• Record Type: Journal Article
• Authors: Yadav, Sarita; Ghrera, Aditya Sharma; Devi, Ambika; Rana, Abhimanyu
• Is Part Of: Electrochimica acta. Volume 437(2023)
• Publication Date: 2023-01-01
• Subjects: Supercapacitor -- Hydrothermal technique -- Nickel cobaltite -- Titanium nitride -- Cathodic arc deposition -- Electrochemical performance; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2022.141526
• Languages: English
• ISSNs: 0013-4686

Abstract

Highlights: Hierarchical flower-like NiCo2 O4 @TiN nanosheets are grown on nickel foam as binder-free electrodes. A two-step hydrothermal process followed by vacuum cathodic arc deposition is used for the preparation of electrodes. NiCo2 O4 @TiN-220/Ni composite electrode delivered a specific capacity of 402.57 Cg −1 at a constant current density of 1 Ag −1 . A symmetric coin cell NCO@TiN-220/Ni supercapacitor delivered a high energy density of 46.4 Wh kg −1 at a power density of 1363 W kg −1 . Abstract: Fabrication of high-performance supercapacitors involves a three-step strategy - selection of suitable electrode material, optimized morphology, and efficient synthesis approach. For the first time, an integrated synthesis approach using the facile hydrothermal technique (for growing NiCo2 O4 nanosheets) followed by vacuum cathodic arc deposition (for depositing thin TiN layers) is used to improve the electrochemical stability of pristine nickel cobaltite (NiCo2 O4 ). The hierarchical flower-like NiCo2 O4 @TiN nanosheets grown on nickel foam as binder-free electrode shows a high specific capacity of 402.57 Cg −1 at 1 Ag −1, excellent rate capability of 82.8% when current density increases from 1 Ag −1 to 20 Ag −1, and cycling stability of 90% over 2000 charge-discharge cycles. The remarkable electrochemical performance of NiCo2 O4 @TiN-220/Ni signifies its ample potential for the fabrication of a supercapacitor device. A coin-cell symmetric supercapacitor (CR2032) is assembled using the NiCo2 O4 @TiN-220/Ni electrodes, which exhibits remarkable electrochemical performance, including a specific capacitance of 178 Fg −1, an energy density of 46.4 Wh kg −1 at a power density of 1363 W kg −1, and a capacitance retention of 129.4% after running 3500 cycles. The enhanced performance can be attributed to the porous morphology with core/shell flower-like nanosheet structure of NiCo2 O4 @TiN grown on nickel foam. The study also emphasizes a good tuning of crystalline metal oxide (NiCo2 O4 ) with amorphous metal nitride (TiN) as high performing electrode for supercapacitor application. Graphical abstract: Image, graphical abstract