Bio-waste wood-derived porous activated carbon with tuned microporosity for high performance supercapacitors

In this study, we have processed renewable waste sticks/woods into eco-friendly porous activated carbon (AC) for renewable energy storage systems. The electrochemical behaviors of porous AC synthesized by chemical activation methods are studied in 6.0 M KOH electrolyte for supercapacitor application. The activation and pyrolysis treatments play a vital role not only in controlling the microstructure of the AC but also in improving the degree of graphitization and porosity. The AC processed at a pyrolysis temperature of 800 degrees C (AC-800) shows hierarchical porous nature with the largest pore volume of 0.75 cm3 g-1 and the highest specific surface area of 973 m2 g-1. The AC-800 electrode has good capacitive performance of 408 F g-1 at a current density of 0.5 A g-1 and has a superior rate characteristic along with excellent electrochemical stability. The two-electrode symmetric device excelled with a specific capacitance of 133 F g-1 at a current density of 1 A g-1 in neutral aqueous electrolyte and a high energy density of 20.6 W h kg- 1 due to an extended potential window. The waste birchwood (popsicle sticks) can be used as a promising low-cost precursor for the fabrication of supercapacitors.

Automated summary

In this study, renewable waste sticks/woods were processed into eco-friendly porous activated carbon for renewable energy storage systems. The electrochemical behaviors of the synthesized porous activated carbon were investigated for supercapacitor application. The activation and pyrolysis treatments were found to be crucial in controlling the microstructure, graphitization, and porosity of the activated carbon. The hierarchical porous nature of the activated carbon synthesized at 800 degrees C exhibited excellent capacitive performance, rate characteristic, and electrochemical stability.