Enhanced Mechanical and Electrochemical Properties of Carbon Nanotube Fibers via Embedded Sucrose-Derived Porous Carbon for Mechanoelectrochemical Energy Harvesting

Abstract

Enhancing both mechanical and electrochemical properties of direct-spun carbon nanotube fiber (CNTF) is essential for energy harvesting applications, but conventional strategies often improve one at the expense of the other. Herein, a sucrose-derived porous carbon network is internally formed within the inter-bundle voids of direct-spun CNTFs, simultaneously enhancing their mechanical and electrochemical properties. This sucrose-derived porous internally embedded carbon (SPINE-C) reinforced inter-bundle connectivity while preserving the alignment of CNTs, thereby enhancing the tensile strength (235-350 MPa), torsional durability (177.5-294.4 mN<middle dot>m<middle dot>mm-3), and toughness (5-20 J g-1) of the CNTFs without compromising their flexibility. Additionally, the microporous structure of SPINE-C expanded the electrochemically accessible surface area, improving in charge storage capacity from 7.2 to 8.0 F g-1. These enhancements in mechanical and electrochemical properties translated into superior energy harvesting performance in SPINE-C-based mechano-electrochemical energy harvester (MEEH), with the power density increasing from 16.2 to 46.0 W kg-1 at 1 Hz-a 2.8-fold enhancement. These results highlight the potential of the SPINE-C strategy as a scalable and high-performance electrode platform for fiber-based energy harvesters, wearable electronics, and smart textiles.