High-Output Moisture-Electric Generator Based on High-Conductive Anti-Freezing Poly(Acrylamide)/NaCl Ionic Hydrogel

Moisture-electric generators (MEGs) have emerged as a promising strategy for harvesting energy from omnipresent atmospheric moisture, which is still compromised by restricted electrical output and harsh working temperatures. Herein, a high-output MEG based on high-conductive anti-freezing poly(acrylamide)/NaCl ionic hydrogel (PNIH) is developed to convert ambient chemical potential energy into electricity. The PNIH-based MEG (PNIH-MEG) can achieve excellent electrical outputs with a continuous output voltage of 1.6 V for 16 days, a current density of 1.2 mA/cm 2 , and a power density of 129 µW/cm 2 , which is attributed to synergistic effects of moisture-induced ion migration, interfacial electrical double layer, interfacial reactions, and high conductivity of PNIH. Especially, the persistent voltage output (1.6 V) of the PNIH-MEG is still maintained even under harsh working conditions of low temperature (−20°C) and low relative humidity (20% RH), which indicates a fascinating all-weather operational capability. Furthermore, an integrated array composed of 72 MEGs in series or 6 MEGs in parallel generates a voltage of 120 V or a current of 5.0 mA, respectively, which can further charge commercial capacitors and directly power ten thermohydrometers. Consequently, this work demonstrates new insights for designing renewable, clean, and sustainable power generation with high-output performance and environmental adaptability.