Department of Chemistry and the Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada.
ACS Nano. 2015 Jul 28;9(7):7248-55. doi: 10.1021/acsnano.5b02075. Epub 2015 Jun 16.
We report the fabrication of high-performance, self-standing composite sp(2)-carbon supercapacitor electrodes using single-walled carbon nanotubes (CNTs) as conductive binder. The 3-D mesoporous mesh architecture of CNT-based composite electrodes grants unimpaired ionic transport throughout relatively thick films and allows superior performance compared to graphene-based devices at an ac line frequency of 120 Hz. Metrics of 601 μF/cm(2) with a -81° phase angle and a rate capability (RC) time constant of 199 μs are obtained for thin carbon films. The free-standing carbon films were obtained from a chlorosulfonic acid dispersion and interfaced to stainless steel current collectors with various surface treatments. CNT electrodes were able to cycle at 200 V/s and beyond, still showing a characteristic parallelepipedic cyclic votammetry shape at 1 kV/s. Current densities are measured in excess of 6400 A/g, and the electrodes retain more than 98% capacity after 1 million cycles. These promising results are attributed to a reduction of series resistance in the film through the CNT conductive network and especially to the surface treatment of the stainless steel current collector.
我们报告了使用单壁碳纳米管 (CNT) 作为导电粘结剂来制造高性能、自支撑复合 sp(2)-碳超级电容器电极。基于 CNT 的复合电极的 3-D 中孔网状结构允许离子在相对较厚的薄膜中不受阻碍地传输，并允许与基于石墨烯的器件相比在 120 Hz 的交流线路频率下具有更好的性能。对于薄碳薄膜，获得了 601 μF/cm(2) 的 601 μF/cm(2) 的电容和-81°的相位角以及 199 μs 的倍率性能 (RC) 时间常数。这些自支撑碳膜是从氯磺酸分散体中获得的，并与具有各种表面处理的不锈钢集流器相连接。CNT 电极能够以 200 V/s 及更高的速度循环，在 1 kV/s 时仍显示出特征的平行六面体循环伏安形状。电流密度超过 6400 A/g，并且电极在 100 万次循环后保留超过 98%的容量。这些有希望的结果归因于通过 CNT 导电网络降低了薄膜中的串联电阻，特别是归因于不锈钢集流器的表面处理。
