Polymerically-enhanced nonwoven recycled carbon fibres used as capacitor electrodes

Here we demonstrate the use of reclaimed non-woven carbon fibre fabrics as electrodes in capacitors. An established polymer surface grafting process (poly(ortho-phenylenediamine, PoPD) was adapted from virgin carbon fibre, giving a 157% improvement (vs. control) in specific capacitance of these fibres at 100 mA/g. Device fabrication using the modified materials gave excellent cycling stability of 96% (over 5000 cycles) was observed for the laminates incorporating PoPD modified fabrics. The flexural properties of the control specimens found a flexural strength and modulus of 8.28 ± 0.55 MPa and 1.02 ± 0.13 GPa, respectively. Improvements to 14.6 ± 1.06 MPa (+76.5%) and 1.60 ± 0.2 GPa (+56.2%) with the presence of PoPD on the reclaimed fibre surface were observed, highlighting the potential synergy of the surface modification for the improvement of physical and electrochemical properties.