Investigating Correlations Between the Microstructures of Different Wood Species and their Performances as Supercapacitor Electrodes*

Supercapacitors typically rely on activated carbon derived from nonrenewable sources, but biochar derived activated carbon serves as a renewable alternative. Future research demands more information about the performance of different biomasses as activated carbon. This study explores the performance of biochars derived from Boxelder, Buckthorn, Bur Oak, and Green Ash. Wood samples were pyrolyzed with a Top-Lit Updraft Gasifier before undergoing KOH chemical activation in a tube furnace. Activated carbon was then used as supercapacitor electrodes. The supercapacitors were tested and analyzed for their specific capacitance, cycling stability, and internal resistance. Bur Oak supercapacitors have achieved excellent results reaching a specific capacitance of 105.6 F/g, and a cycling stability of 98.59% over 250 cycles all at 0.5mA. Compared to supercapacitors made from commercially available activated carbon reaching a specific capacitance of 102.0 F/g, cycling stability of 94.17%, as well as qualitatively determining that wood biochar supercapacitors achieved a lower internal resistance, it is apparent that wood biochars can outperform commercial activated carbon. This study will assess the performance of biochars derived from the four wood species and provide insight into correlations between wood microstructures and their applications for supercapacitor electrodes.