title: High Performance Carbon Nanotube Yarn Supercapacitors with a Surface-Oxidized Copper Current Collector.
abstract: Threadlike linear supercapacitors have demonstrated high potential for constructing fabrics to power electronic textiles (eTextiles). To improve the cyclic electrochemical performance and to produce power fabrics large enough for practical applications, a current collector has been introduced into the linear supercapcitors to transport charges produced by active materials along the length of the supercapacitor with high efficiency. Here, we first screened six candidate metal filaments (Pt, Au, Ag, AuAg, PtCu, and Cu) as current collectors for carbon nanotube (CNT) yarn-based linear supercapacitors. Although all of the metal filaments significantly improved the electrochemical performance of the linear supercapacitor, two supercapacitors constructed from Cu and PtCu filaments, respectively, demonstrate far better electrochemical performance than the other four supercapacitors. Further investigation shows that the surfaces of the two Cu-containing filaments are oxidized by the surrounding polymer electrolyte in the electrode. While the unoxidized core of the Cu-containing filaments remains highly conductive and functions as a current collector, the resulting CuO on the surface is an electrochemically active material. The linear supercapacitor architecture incorporating dual active materials CNT + Cu extends the potential window from 1.0 to 1.4 V, leading to significant improvement to the energy density and power density.
authors.affiliation: Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission & Ministry of Education, South-Central University for Nationalities , Wuhan, Hubei Province 430074, China.
authors.forename: Daohong
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission & Ministry of Education, South-Central University for Nationalities , Wuhan, Hubei Province 430074, China.
authors.forename: Yunlong
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission & Ministry of Education, South-Central University for Nationalities , Wuhan, Hubei Province 430074, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Li
authors.affiliation: Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission & Ministry of Education, South-Central University for Nationalities , Wuhan, Hubei Province 430074, China.
authors.forename: Yin
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission & Ministry of Education, South-Central University for Nationalities , Wuhan, Hubei Province 430074, China.
authors.forename: Aiqing
authors.initials: A
authors.lastname: Zhang
authors.affiliation: CSIRO Manufacturing , P. O. Box 21, Belmont, Victoria 3216, Australia.
authors.forename: Menghe
authors.initials: M
authors.lastname: Miao
keywords: carbon nanotube yarn; current collector; linear supercapacitor; metal filament; potential window