Tuning the linear actuation of multiwall carbon nanotube fibers with carbide-derived carbon

Abstract

Fibers made from carbon nanotubes (CNT) have received a lot of attention, including for the intended applications in “artificial muscles”. Combination of CNT fibers with high capacitance particles such as carbide-derived carbon (CDC) is the focus of this research. A dielectrophoretic method was used to form novel CNT-CDC fibers with different wt% of CDC from 25% to 75%. The CNT-CDC fibers were compared to pristine CNT fibers in their electromechanical response to different electrochemical driving regimes (cyclic voltammetry, square wave potential steps) in an organic electrolyte. The best performance in strain and stress was achieved by CNT-CDC(50%) with nearly double charge density and 1.5 times higher electronic conductivity in comparison to pristine CNT fibers. The determination of the specific capacitance over chronopotentiometric measurements revealed 175 F g−1 (0.54 A g−1) for CNT-CDC(75%) fibers, while the best stability and charging durability was shown by CNT-CDC(50%). The CNT-CDC fibers demonstrated consistent dual functionality for potential applications in linear actuators, supercapacitors or in multifunctional designs.