Robust Single-Walled Carbon Nanotube-Infiltrated Carbon Fiber Electrodes for Structural Supercapacitors: from Reductive Dissolution to High Performance Devices

Multifunctional electrodes for structural supercapacitors are prepared by vacuum infiltration of single-walled carbon nanotubes (SWCNTs) into woven carbon fibers (CFs); the use of reductive charging chemistry to form nanotubide solutions ensured a high degree of individualization. The route is highly versatile, as shown by comparing four different commercial nanotube feedstocks. In film form, the pure nanotubide networks (buckypapers) are highly conductive (up to 2000 S cm(-1)) with high surface area (>1000 m(2) g(-1)) and great electrochemical performance (capacitance of 101 F g(-1), energy density of 27.5 Wh kg(-1) and power density of 135 kW kg(-1)). Uniformly integrating these SWCNT networks throughout the CF fabrics significantly increased electrical conductivity (up to 318 S cm(-1)), surface area (up to 196 m(2) g(-1)), and in-plane shear properties, all simultaneously. The CNT-infiltrated CFs electrodes exhibited intrinsically high specific energy (2.6-4.2 Wh kg(-1)) and power (6.0-8.7 kW kg(-1)) densities in pure 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIM TFSI) electrolyte. Multifunctional structural supercapacitors based on CNT-coated CFs offer a substantial increase in capacitive performance while maintaining the tensile mechanical properties of the as-received CF-based composite. This non-damaging approach to modify CFs with highly graphitic, high surface area nanocarbons provides a new route to structural energy storage systems.

Automated summary

Multifunctional electrodes for structural supercapacitors were prepared by infiltrating single-walled carbon nanotubes (SWCNTs) into woven carbon fibers (CFs) using a vacuum method. The use of reductive charging chemistry ensured a high degree of individualization. The resulting electrodes showed high conductivity, surface area, and electrochemical performance, and significantly improved the electrical conductivity, surface area, and in-plane shear properties of the CF fabrics. Structural supercapacitors based on these electrodes exhibited high specific energy and power densities in the chosen electrolyte. This approach provides a new route to structural energy storage systems.