Plasma surface functionalization induces nanostructuring and nitrogen-doping in carbon cloth with enhanced energy storage performance

Abstract

A facile, one-step and environmentally-friendly strategy for the preparation of hierarchical nitrogen-doped carbon cloth (hNCC) is presented via nitrogen plasma processing of commercial carbon cloth. In addition to N-doping, the RF plasma treatment induces nanostructuring, thus significantly increasing the surface area and liquid electrolyte wettability. The untreated carbon cloth (CC) has negligible Li-ion and supercapacitive storage capacities. However, after plasma treatment, the obtained hNCC delivers dramatically enlarged capacities. Specifically, the enhancement is by three times for Li-ion storage (150 mA h g⁻¹versus 50 mA h g⁻¹ at 100 mA g⁻¹), and by three orders of magnitude for pseudocapacitance (391 mF cm⁻²versus 0.12 mF cm⁻² at 4 mA cm⁻²). The effect of power-dependent plasma treatment for optimized performance is also investigated. We propose a plausible mechanism for achieving a hNCC architecture with highly enhanced ion/charge storage properties. Our research provides an approach to fabricate N-doped carbon materials with a controllable surface morphology and electrochemical properties. This deterministic and plasma-based method of preparing hNCC may offer new opportunities in the design and fabrication of high-performance carbon-based electrodes for energy storage devices.