Development of Mesoporous Carbon Composites with Waste Plastics Derived Graphene and MnO₂ for Supercapacitor Applications

Abstract

This study demonstrates the influence of incorporating composites such as waste plastics derived graphene (WPDG) and manganese dioxide (MnO2) in the mesoporous carbon (CR) and their consequent characteristics. The CR having WPDG as composite is named as CRG and MnO2 containing CR composite is termed as CRM. CRG possess the surface area as high as 790 m²g-1 along with pore volume of 0.565 cc g-1 and radius of 3.82 nm. Cyclic voltammetry (CV) study suggested that CR and CRG showed non-Faradic capacitive behavior with almost rectangular shaped CV profiles at low scan rates and this shows the existence of electric double layer structure. On the other hand, pseudo-capacitance is observed for CRM. Galvanostatic charge/discharge investigation revealed that the specific capacitance can be enhanced by 6 times upon subsequent immobilization of WPDG in CR whereas 4-fold upgrading in the specific capacitance after treating CR with MnO2. Interestingly, CRM showed higher capacitance retention as compared to CRG and is attributed to its smaller value of equivalent series resistance as compared to CRG. Ragone plots shown that the higher energy and power densities are found for the case of CRG.

Binder-free all-carbon composite supercapacitors

“…A comparison between the specific capacitances of carboncarbon composite electrodes fabricated by different methods and tested in various electrolytes is presented in table 1. For instance, Murugan et al, fabricated the mesoporous carbon-based composite with waste plastic-derived graphene using PVDF as a binder [41]. The composite electrode delivers a capacitance of 18.6 F g −1 at a current density of 0.05 A g −1 in a 6 M KOH electrolyte solution.…”

Polyaniline modified waste‐derived graphene/sulfur nanocomposite cathode for lithium–sulfur batteries

“…However, these wastes are biodegradable, whereas the plastic wastes are nonbiodegradable and their accumulation is a serious concern worldwide. Recently, researchers have started working in the area of development of supercapacitors using WDG derived from the plastic wastes 19–21 …”

“…Recently, researchers have started working in the area of development of supercapacitors using WDG derived from the plastic wastes. [19][20][21] Sulfur being electrically insulating needs to be immobilized to conductive matrix in order to be electrochemically active in Li-S batteries. Carbon is considered to be one of the most suitable substrates for sulfur immobilization as both sulfur and carbon are mutually compatible and a wide variety of nanostructures of carbon are possible to obtain.…”