Piezoelectric-Driven Self-Powered Patterned Electrochromic Supercapacitor for Human Motion Energy Harvesting

The rapid development of a self-powered system (SPS) has aroused an increasing interest in the field of wearable electronics. The current development trend in wearable electronics is toward integration, portability, miniaturization, and sustainability. Hence, a wearable piezoelectric-driven self-powered patterned electrochromic super-capacitor (ESC) is presented here, which is integrated with the energy harvesting, conversion, storage and indication technologies. The patterned polyaniline (PANT) electrodes electrodeposited by coupling cyclic voltammetric and galvanostatic (CV-GS) techniques were assembled as patterned ESC, which served to store the energy and indicate the charging/discharging status simultaneously. With the advantages of flexibility and biocompatibility, the polyvinylidene difluoride (PVDF) nanofibers were fabricated by electrospinning to establish the piezoelectric nanogenerators (PENGs) as the energy-harvesting device, which can be attached to human body to harvest mechanical kinetic energy. The integrated wearable self-powered system (SPS) can harvest human motion energy and other mechanical energy, then transfer the mechanical energy to electric energy by a rectifier for charging ESC, which provides a sustainable energy supply for wearable electronics. It is foreseen that the self-powered patterned ESC that we proposed will have a broad application in the fields of flexible artificial skin, smart robots, artificial intelligence, and implantable or portable medical devices.