High-efficiency moisture energy harvesting at −30 °C via hybrid solute engineering†

Moisture energy harvesting, which directly converts atmospheric moisture into electricity, has emerged as a transformative solution for sustainable power generation. However, freezing-induced ion migration blockage in moisture-electricity generators (MEGs) remains a significant barrier, limiting their viability in harsh climates. We introduce a molecularly engineered hybrid solute strategy that orchestrates hydrogen-bond network dynamics through synergistic interactions between anionic salts and organic solvents. This design restructures the hydrogen-bond network, suppressing ice nucleation while promoting ion dissociation, thereby enabling sustained ionic transport and superior electrical performance in subzero environments. The proposed MEG demonstrated exceptional antifreeze performance, maintaining stable output at −30 °C with 0.67 V and 86.2 μA cm⁻², achieving a tenfold improvement over conventional systems. Moreover, long-term tests confirmed continuous operation for over 10 days at −25 °C and 50% relative humidity, consistently generating 0.74 V, underscoring its reliability in extreme conditions. These results set a benchmark for MEG technology, enabling reliable energy harvesting for environmental monitoring, wearable health devices, and remote sensing in extreme conditions.