Morphological optimization and nitrogen functionalization of vertically oriented CNW for high performance electrical double layer capacitor electrode

The objective of this study is to explore the influence of topographical surface structures and nitrogen doping effects on Carbon Nano Wall (CNW) characteristics in the context of Electrochemical Double-Layer Capacitor (EDLC) electrode applications. Carbon-based materials attract significant technological and industrial interest for EDLC electrode. Among available carbon-based materials, CNW are suitable candidates for EDLC electrodes based on their extremely high surface area and open top edges, which facilitate easy electrolyte circulation. In this study, CNW are synthesized using an electron cyclotron resonance plasma-system. To evaluate the electrochemical performance of synthesized CNW with various surface morphologies, cyclic voltammetry measurements are conducted in three-electrode systems. Elemental analysis is conducted to measure the weight percentages of the synthesized CNW with varying synthesis conditions. It is found that the amount of synthesized CNW and specific capacitance saturate after 15 min of growth, but considerable differences in specific capacitance based on CNW morphology are observed. Further improvements to the specific capacitance of CNW are achieved by introducing a nitrogen plasma post-treatment without any decline in electrochemical characteristics. These encouraging results may motivate additional research on constructing suitable pore distributions for targeting high-power EDLC applications.