Development of a Novel Bio‐based Redox Electrolyte using Pivalic Acid and Ascorbic Acid for the Activated Carbon‐based Supercapacitor Fabrication

Abstract

Supercapacitor is considered a promising energy storage device due to its high‐power density and high specific capacitance. Electrode materials and electrolytes are major components of supercapacitors. The most used electrolytes are not biocompatible, which limits their practical applications. Bio‐electrolytes often cause low performances of supercapacitors. However, the inadequate performances of bio‐electrolytes for supercapacitor applications could be improved using redox molecules. Here, we are reporting the development of a novel redox bio‐electrolyte based on pivalic acid (PA) and ascorbic acid (AA). The salts of PA and AA served as the bio‐electrolyte and redox molecules, respectively. It is worth to note that PA which can be generated from bio‐sources and industrial wastes, is soluble in alkaline solutions. AA is found in most living organisms, including plants. The developed supercapacitor with the bio‐based redox electrolyte provides a specific capacitance of 308 Fg−1 at a current density of 1 Ag−1 and achieved an energy density of 15 Whkg−1 at a power density of 300 Wkg−1. The supercapacitor demonstrates a good coulombic efficiency of ∼97% with capacitance retention of ∼72% after 10000 charge‐discharge cycles. This study is expected to widen the applications of bio‐based redox electrolytes for practical electrochemical energy storage applications and enables access to greener and more sustainable energy storage technology.

A Review of Supercapacitors: Materials Design, Modification, and Applications

“…Maxwell, NEC, Tokin, Panasonic and the Russian Econd company contributed most to the world market. Helmholtz developed the concept of double-layer capacitance by identifying its properties in 1879, but it took decades for double-layer capacitance to be exploited for energy storage [31,34]. In 1957, Becker reported that smaller capacitors could be used as energy storage devices.…”

“…The second component is the electrolyte [34,55,58], a conduction source which can be found in every device [96][97][98]. In a typical capacitor, a dielectric is present.…”

Wrinkled Flower-Like rGO intercalated with Ni(OH)2 and MnO2 as High-Performing Supercapacitor Electrode

“…It is observed that the CV shapes deviate from the perfect rectangular shape beyond the potential of 1.0 V because of the dissociation of water and O 2 /H 2 gas evaluation, shown in Figure 5 a. 34 Furthermore, the ESPW was confirmed from the GCD results of a fixed current density of 1.0 A g –1 as the shape of the GCD curve appeared symmetrical triangle with extended discharge time within the potential of 1.0 V, shown in Figure 5 b. The electrochemical rate capability of as prepared ternary hybrid was done by conducting CVs with different scan rates from 10 to 100 mV s –1 , and GCD performance was conducted at 1.0, 2.0, and 4.0 A g –1 within potential range 0 to 1 V, shown respectively in Figure 5 c,d.…”

Recent Advances in Carbon and Metal Based Supramolecular Technology for Supercapacitor Applications

“…Another key element of an SC is the electrolyte comprising salt and solvent, which typically contributes to determining the operating potential window (OPW) of SCs. The capacitance value depends on the size difference, ionic conductivity, mobility of the system, and thermal and electrochemical stability based on its reactivity at different temperature conditions [110] . Depending on the types of electrolytes (aqueous, organic/inorganic, and ionic liquids) used in SCs, it can offer different OPWs to the SC, either a wide or narrow OPW, affecting the total energy density and power density of the system [115] .…”