Sheaf-Like Carbon Nanotube Composite Architectures for High-Performance Supercapacitor Electrodes in Concentrated Alkaline Media

For core materials with fast response times and adjustable power and energy output for energy storage, we herein report the electrochemical performance and latent hydrogen evolution reaction of sheaf-like carbon nanotube (s-CNT) based material electrodes, aiming for further low-cost synthesis and environmentally friendly supercapacitor applications. XPS scanning spectra show C, O, and a few Mo elements with estimated contents of 82.3, 17.2, and 0.5 at%, respectively. The maximum capacitance of 1287 F g ‒1 is achieved in the s-CNT-based electrochemical double-layer capacitor (EDLC) due to slow ion diffusion in the s-CNT-based electrode during charging and discharging. The Bode phase angle at 80.1° of the s-CNT electrode is close to 90°, and the prepared s-CNT electrode illustrates ideal EDLC capacitance behavior. In addition, the s-CNT electrode, after 2000 subsequent CV and GCD cycles at a current density of 0.95 A g ‒1 , retains specific capacitance of 96.8% and 80.55%, respectively. The s-CNT electrode exhibits reduced ionic resistance and facilitates ion transport through its conductive architecture, demonstrating its potential as a high-performance material for prospective EDLC supercapacitor applications.