Sustainable supercapacitor electrode material contains green synthesized expired drug-functionalized graphene oxide, meat waste-derived carbon, and ionic liquid: Electrochemical performance and management strategies

Reusing waste and seemingly worthless resources has attracted increasing attention. This work used meat waste (MW) to prepare activated carbon (AC) through pyrolysis. AC derived from MW was composited with expired Ganciclovir-functionalized graphene oxide (GG) and 1-benzyl-3-methyl-1H-imidazol-3-ium bromide ionic liquid (IL) to introduce a sustainable composite (GG-MW-IL) for energy storage. Functionalized graphene oxide was prepared in a green solvent (IL) to minimize the environmental impact. A series of instrumental tests confirmed the successful synthesis. The most important data during the structural characterization was the specific surface area of 288.11 m² g⁻¹ for GG-MW-IL composite, which made it suitable for energy storage applications. In the three-electrode (3E) system, the composite electrode recorded a specific capacity of 459 F g⁻¹ @ 1 A g⁻¹. It showed retention of 97.2 % (10,000 charge/discharge loops), demonstrated low resistance, and facilitated effective charge transfer in the 3E system. When configured in a symmetric two-electrode (2E) system (GG-MW-IL//GG-MW-IL), it displayed a specific capacity of 228 F g⁻¹ @ 0.5 A g⁻¹. After 10,000 charge/discharge loops, it maintained a retention capacity of 94.2 % and achieved high energy and power density. Considering the excellent behavior of GG-MW-IL electrodes in a natural supercapacitor system, using low-risk, green, and recycled materials shows the potential to replace traditional materials. The assessment of designed supercapacitors within the circular economy framework highlights that GG-MW-IL exhibits favorable executive-economical attributes, making it particularly suitable for adoption within the energy industry compared to other options.