title: From industrially weavable and knittable highly conductive yarns to large wearable energy storage textiles.
abstract: Wearable electronic textiles that store capacitive energy are a next frontier in personalized electronics. However, the lack of industrially weavable and knittable conductive yarns in conjunction with high capacitance, limits the wide-scale application of such textiles. Here pristine soft conductive yarns are continuously produced by a scalable method with the use of twist-bundle-drawing technique, and are mechanically robust enough to be knitted to a cloth by a commercial cloth knitting machine. Subsequently, the reduced-graphene-oxide-modified conductive yarns covered with a hierarchical structure of MnO2 nanosheets and a polypyrrole thin film were used to fabricate weavable, knittable and wearable yarn supercapacitors. The resultant modified yarns exhibit specific capacitances as high as 36.6 mF cm(-1) and 486 mF cm(-2) in aqueous electrolyte (three-electrode cell) or 31 mF cm(-1) and 411 mF cm(-2) in all solid-state two-electrode cell. The symmetric solid-state supercapacitor has high energy densities of 0.0092 mWh cm(-2) and 1.1 mWh cm(-3) (both normalized to the whole device) with a long cycle life. Large energy storage textiles are fabricated by weaving our flexible all-solid-state supercapacitor yarns to a 15 cm × 10 cm cloth on a loom and knitting in a woollen wrist band to form a pattern, enabling dual functionalities of energy storage capability and wearability.
authors.affiliation: †Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
authors.affiliation: ‡Institute of Textiles and Clothing, The Hong Kong Polytechnic University, 11 Hong Chong Road, Hong Kong, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Hu
authors.affiliation: †Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Huang
authors.affiliation: †Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China.
authors.forename: Minshen
authors.initials: M
authors.lastname: Zhu
authors.affiliation: †Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China.
authors.forename: Wenjun
authors.initials: W
authors.lastname: Meng
authors.affiliation: ‡Institute of Textiles and Clothing, The Hong Kong Polytechnic University, 11 Hong Chong Road, Hong Kong, China.
authors.forename: Chang
authors.initials: C
authors.lastname: Liu
authors.affiliation: †Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China.
authors.forename: Zengxia
authors.initials: Z
authors.lastname: Pei
authors.affiliation: ∞Department of Mechanical and Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China.
authors.forename: Chonglei
authors.initials: C
authors.lastname: Hao
authors.affiliation: ∞Department of Mechanical and Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China.
authors.forename: Zuankai
authors.initials: Z
authors.lastname: Wang
authors.affiliation: †Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China.|§Shenzhen Research Institute, City University of Hong Kong, Shenzhen 518000, China.
authors.forename: Chunyi
authors.initials: C
authors.lastname: Zhi
mesh_terms: D025802:Electric Capacitance; D004553:Electric Conductivity; D004563:Electrochemistry; D004566:Electrodes; D006108:Graphite / Q000737:chemistry; D007221:Industry; D017895:Manganese Compounds / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D010087:Oxides / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D011758:Pyrroles / Q000737:chemistry; D013784:Textiles
chemical_list: D017895:Manganese Compounds; D010087:Oxides; D011108:Polymers; D011758:Pyrroles; C067635:polypyrrole; C027424:manganese oxide; D006108:Graphite
keywords: energy storage textiles; knittability; wearability; weavability; yarn supercapacitors