Abstract There is an urgent need to develop flexible yarn-type supercapacitors with excellent electrochemical and mechanical properties for flexible energy storage devices in portable and wearable electronics. In this study, graphene oxide (GO) nanosheets and polyacrylonitrile (PAN)-GO nanofibres were coated on the surface of Ni-plated cotton yarn (NCY) via conjugate electrospinning technology, followed by chemical deposition of a polypyrrole (PPy) layer through in situ polymerisation of pyrrole, obtaining a flexible wearable PPy@GO/PAN-GO@Ni-coated cotton core-spun yarn (PGPG/NCY) electrode. The synergetic effect of NCY, GO/PAN-GO nanofibres, and PPy nanoparticles imparted a hierarchically porous structure, good conductivity, and high tensile strength (71.43 MPa) to this electrode. A flexible symmetric all-solid-state two-ply yarn supercapacitor based on PGPG/NCY electrodes was assembled. This yarn supercapacitor exhibited a high areal specific capacitance (28.34 mF cm −2 ) and high energy density (3.98 μWh cm −2 ), which are superior to those of other yarn supercapacitors. The capacitance retention of this yarn supercapacitor remained at 90.2% after 1000 cyclic voltammetry cycles and 100% at different bending angles; the yarn supercapacitor exhibited high electrochemical performance and cycling stability. Thus, the proposed high-performance yarn supercapacitor based on PGPG/NCY electrodes is promising and widely applicable in wearable devices. Graphical Abstract
Lin Li,Dou Du,Chengen He,Lianqing Yu,Wenyang Tang,Shuang Hu,Xinyu Wang,Zhuan Fu,Liangjun Xia,Weilin Xu,Lingxue Kong
Cotton fibers, a natural cellulose , have played a critical role in the development of wearable energy storage, owning to their wearability, integrability, eco-benignity, and cost effectiveness. Graphene, a two-dimensional carbon material, possesses excellent electrochemical properties that can be incorporated into cotton yarns to enhance their performance. However, the conventional chemical reduction processes use corrosive chemical reducing agents that limit their wide application. In the current study, a reduced graphene oxide (rGO)/cotton (RC) yarn supercapacitor was fabricated employing a facile and green hydrothermal approach without the use of any chemical reductants. The reduction efficiency of external GO nanoparticles and the morphology change of internal cotton fiber under different hydrothermal treatments are investigated to explore their effects on the energy storage performance of the resultant RC electrodes and supercapacitors. The RC yarn electrode can reach a capacitance of 13.31 mF cm −1 at of 0.1 mA cm −1 . The assembled asymmetric supercapacitor exhibited a high specific capacitance of 2.99 mF cm −1 (9.54 mF cm −2 , and 381.43 mF cm −3 ) at 0.02 mA cm −1 (0.06 mA cm −2 and 2.55 mA cm −3 ) with a high energy density of 0.42 μWh cm −1 (1.32 μWh cm −2 and 0.05 mWh cm −3 ) at a power density of 10 μW cm −1 (31.84 μW cm −2 and 1.27 mW cm −3 ). This work develops a green versatile strategy for fabricating RC supercapacitors, which may provide a new avenue for wearable energy storage devices.
Zhen Zeng,Baowei Hao,Daiqi Li,Deshan Cheng,Guangming Cai,Xin Wang
Yarn-based wearable sensors have attracted attention, but it is difficult to fabricate yarn strain sensors with large-scale production, weavability, dyeability and durability toward real applications as wearable electronics and smart textiles. Herein, we report a facile core spun strategy to fabricated spandex/CNT cotton yarns (SCCY) on an industrial spinning machine. For the first time, wearable sensor could be dyed through a simple dip dyeing process with different colors (red, yellow, blue and black). The unique core-sheath structure endowed the yarn with good sensitivity (gauge factor of 21.85 at 300% strain), broad sensing range (0%-300% strain), excellent durability (against dip dyeing, washing, acid and alkali) and abrasion resistance (resistance change 5% after rubber 100 cycles). The sensor yarn was also successfully woven/knitted into textiles and it could be sewn into a fabric. The weavable and dyeable core-spun yarn in the present work provide a feasible way for industrial-scale manufacture wearable sensors.
危险品化学品经营许可证（带存储）