Fabrication of carbon cloth supported Ni@Fe double hydroxide based electrode for flexible supercapacitor applications

Abstract

Herein, we have decorated the nickel-iron hydroxide (Ni@Fe LDH) directly on the carbon cloth (CC) to fabricate a flexible and binder-free electrode for electrochemical applications. The samples produced were characterized by versatile physical techniques to investigate the surface area, crystallographic structure, chemical composition, and morphology. The Ni@Fe LDH/CC electrode exhibited the high gravimetric capacitance (Cg) of 984 Fg-1 at 1 Ag-1 that is the result of the synergistic effect of hybrid composition, higher surface area, porous structure, and binder-free design. The fabricated electrode showed astonishing cyclic stability, as it retains nearly 87.6% of the initial capacity after 7000 consecutive galvanostatic charge-discharge (GCD) experiments. The best experimental cyclic activity is accredited to the flexible substrate, layered morphology, and porous architecture of the fabricated electrode that protects it from the expected pulverization and expansion processes. Additionally, our flexible and binder-free electrode showed excellent rate-performance and lost just 13.5% gravimetric capacitance when the applied current density value is changed from 1 to 9 Ag-1. In fact, numerous voids and pores of the Ni@Fe LDH sample act as ion-reservoirs and facilitate mass transport even at the higher current density. The electrochemical results ensure that our flexible electrode, thanks to its integrated capacitive performance, has the potential for practical applications in flexible energy storage systems.