Nickel foam supported hierarchical NiCo2S4@NiFe LDH heterostructures as highly efficient electrode for long cycling stability supercapacitor. (1st April 2023) - Rabbani, Syeda Sughra
Abstract: Layered double hydroxides (LDHs) based heterostructures provide an opportunity for the development of high-performance supercapacitors. Up till now, hierarchical NiCo2 S4 @NiFe LDH heterostructure is scarcely investigated for supercapacitor. In this work, the hierarchical NiCo2 S4 @NiFe LDH heterostructure nanosheet arrays on Ni-foam (NF) were synthesized by a facile hydrothermal method. As the supercapacitor electrode, it has been revealed that the incorporation of NiFe can significantly increase the capacitive performance of the heterostructure. At a current density of 1 Ag −1, a specific capacitance of NiCo2 S4 @NiFe LDH electrode was reached up to 827 Fg −1, outperforming that of pristine NiCo2 S4 and NiFe LDH. Moreover, the electrode keeps 90.2% of its preliminary capacitance after 12, 000 cycles at 5 A g −1 . In addition, NiCo2 S4 @NiFe LDH electrode offer high energy density of 38.1 W h kg −1 and power density of 1800 W kg −1 . According to DFT calculations, NiFe-LDH adsorption on NiCo2 S4 is strong and governed by large interfacial interactions with a charge transfer of 0.44 eV to NiCo2 S4 surface thus demonstrating the significantly improved electrochemical performance. Hence, such an outstanding electrochemical finding suggest that NiCo2 S4 @NiFe LDH heterostructures could be attractive electrode materials as practical supercapacitors for next generation energy storage devices. Graphical abstract: Image, graphical abstract