One-step preparation of gel-electrolyte-friendly fiber-shaped aerogel current collector for solid-state fiber-shaped supercapacitors with large capacity

Fiber-shaped aerogel conductive structures are a promising template for preparing fiber-shaped supercapacitors with high length-specific capacitance used in flexible and wearable electronics. The challenge lies in how to easily infiltrate enough active mass and gel electrolyte into micropores and achieve intimate contact so that the active mass can be fully utilized for large capacitance and small contact resistance to be obtained for fast rate response. Here, one-step preparation of gel electrolyte friendly, fiber-shaped conductive and hydrophilic aerogel is reported, which was produced from electrospinning poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PP) and poly(ethylene oxide) (PEO) on a centering Ti metal wire. Thanks to the high conductivity of PP, high hydrophilicity of PEO, high porosity of the aerogel structure and high mass loading of PP, the as-prepared PP-PEO/Ti showed a fiber-length-specific capacitance of 68.4 mF cm⁻¹ and excellent rate performance due to well infiltration of gel electrolytes. More interestingly, PP-PEO/Ti was used as a template to load polyaniline (PANI). The as-prepared PANI@PP-PEO/Ti fibers were studied as electrodes in solid-state supercapacitors. A fiber-length-specific capacitance is as large as 136.7 mF cm⁻¹ was measured. These results suggest our PP-PEO/Ti is a promising 3D fiber-shaped aerogel structure for high-performance fiber energy storage devices.