Flexible solid-state self-charging supercapacitor based on symmetric electrodes and piezo-electrolyte

Abstract

Fabrication of flexible power source that can provide sustainable energy is regarded as one promising strategy to address the working issue of wearable electronics in the case of no electricity or charging base. Herein, a novel flexible solid-state self-charging supercapacitor (SCSC) was creatively proposed by employing Co-doped Fe2O3 grown on activated carbon cloth (Co-Fe2O3@ACC) as advanced symmetric electrodes and BaTiO3 piezoelectric particles mixed PVA-KCl gel film (PVA-KCl-BaTiO3) as piezo-electrolyte. The as-fabricated device possesses combined advantages including high flexibility, and considerable electrochemical and self-charging capability. Particularly, it can synchronously harvest and store energy via force-electric conversion with piezoelectric effect, and hence be easily self-charged to about 120 mV by simple impacting (repeated bending for 7 min at a frequency of 1.0 Hz). The acceptable self-charging capability coupled with the unique design enables the electrochemical device promising application potential for sustainable and portable wearable electronics.