Non-Thermal Pulsed Plasma Synthesis of Carbon Nanomaterials from Hydrocarbons: Morphology and Energy Storage

Carbon nanomaterials have garnered significant attention due to their exceptional electrical, thermal, optical, and mechanical properties, and are synthesized from hydrocarbon gases. This study explores the synthesis of carbon nanomaterials (CNMs) using a pulsed-plasma process with acetylene as the primary feedstock. By adjusting plasma parameters, such as energy input and feedstock composition, we successfully tuned the morphology, crystallinity, and electrochemical properties of the resulting CNMs. Supercapacitor testing demonstrated that our CNM outperformed commercial standards (such as Super P) as a conductive additive, achieving a higher specific capacitance of 72.6 F/g (vs 68.2 F/g) for activated carbon at 0.1 A/g while maintaining excellent stability (100% capacitance retention at 2A/g after 10,000 cycles). This enhancement is attributed to the combined effects of increased hydrophilicity from oxygen functional groups and the prenetworked structure of CNM that promotes efficient electron transport within the electrode. This work highlights the versatility of the pulsed-plasma process in producing high-quality carbon nanomaterials from low-value hydrocarbon feedstocks.