Bioinspired moist-electric generator with self-protection and autonomous healing enabled by dynamic supramolecular polyurethane

Flexible moist-electric generators (MEGs) capable of harvesting energy from atmospheric moisture have emerged as promising sustainable power sources for wearable electronics. However, their softness characteristic renders them vulnerable to mechanical damage (e.g., accidental impacts and punctures), consequently resulting in device failure. Here, inspired by the dynamic characteristics of sea cucumber skin, a self-protective, self-healing, and high power-output MEG was developed by integrating a stimuli-responsive supramolecular polyurethane (USPU). The USPU network was well engineered via transient quadruple hydrogen bonds and highly dynamic disulfide bonds, thereby achieving exceptional flexibility, impact-hardening and self-healing properties. Upon integration of USPU as a moisture barrier, the resulting MEG exhibited high power outputs (i.e., 1.05 V in voltage and 23.3 μA cm −2 in current density), while the USPU could protect the inner functional components from damage under severe mechanical stimuli. Moreover, the MEG also had good self-healing property, exhibiting complete recovery in resistance and voltage output after healing. In light of these unique properties, the application of MEG has been demonstrated as wearable power source, which generates stable electric output even under extreme collision and puncture events. This work provides a versatile strategy for developing mechanical robust and high-performance energy supply systems for wearable electronics.