Flexible and wearable wire-shaped microsupercapacitors based on highly aligned titania and carbon nanotubes

Wire-shaped devices, such as solar cells and supercapacitors, have attracted great attentions due to their unique structure and promise to be integrated into textiles as portable energy source. To date, most reported wire-shaped supercapacitors were developed based on carbon nanomaterial-derived fiber electrodes where as titania was much less used, though with excellent pseudocapacitvie properties. In this work, we used a titanium wire sheathed with radially aligned titania nanotubes as one of the electrodes to construct all-solid-state micro supercapacitors, in which the second electrode was carbon nanotube fiber or sheet. The capacitance of the resulting microsupercapacitor with a CNT sheet electrode (1.84 mF cm(-2)) is a bout three time of that for the corresponding device with the second electrode based on a single CNT yarn. The unique wire-shaped structure makes it possible for the wire-shaped micro-supercapacitors to be woven into various textiles and connected in series or parallel to meet a large variety of specific energy demands. (C) 2015 Elsevier B.V. All rights reserved.