Rapid joule-heating activation boosted capacitive performance of carbon fibers

Abstract

The traditional activation methods for carbon fibers (CFs) such as strong acid etching are corrosive, time consuming and heavily polluting. In this paper, we report a fast and environment-friendly method to activate CF by a one-step joule-heating process. With only 10 min treatment, the oxygen content in the fiber surface reaches to 24.6%, and the activated CF with hierarchically porous structure and exfoliated surface layers is obtained. As a fiber electrode, it reveals a specific capacitance of 162 F g−1, which is 125 times of the non-activated CF. Furthermore, the joule-heating activation also facilitates the growth of foreign component on fiber surface and strengthens their interfacial interaction. This work provides a novel approach for the rapid fabrication and functionalization of CF-based devices and composites.