Low Temperature Synthesis of Iron Oxide and Nickel Phosphide Based Flexible Redox Electrodes for Supercapattery Application

Abstract

Energy storage systems play a vital role in rationalizing the imminent energy crisis and ecological discomfort. The modern tactic of resolving the lack of energy density dispute with the flexible supercapattery systems that could provide both high power and energy density in any form such as bending, stretching, twisting, and folding modes are trending in the field of energy storage devices. Here, we interpret a facile and efficient low-temperature approach to prepare iron oxide (Fe3O4) and nickel phosphide (Ni2P) as anode and cathode, respectively. The formation of well-defined, highly crystalline and single-phase pure Fe3O4 and Ni2P was identified through XRD and XPS analysis. The morphological feature portrays the uniform distribution of both the Fe3O4 and Ni2P nanoparticles. The electrochemical activity of the prepared Fe3O4 and Ni2P electrodes revealed improved storage capacity of 106 and 354 C g-1 at a current density of 3 and 1 A g-1, respectively. Successively, a lab scale flexible supercapattery device (Fe3O4 || Ni2P) was fabricated with an improved energy density (31.5 W kg-1) and superior power density (6400 Wh kg-1). Moreover, the fabricated device showed resilient strength and high cyclic stability by retaining 80 % of its initial capacity for about 20000 cycles. Therefore, a facile low-cost route is proposed to fabricate an efficient, flexible supercapattery system with improved storage property expressive kinetics, resilient strength and enhanced flexibility established itself as a potential material for supercapacitor application.