Moisture-Electric Generators Working in Subzero Environments Based on Laser-Engraved Hygroscopic Hydrogel Arrays

作者：Fei Yu, Liying Wang, Xijia Yang, Yue Yang, Xuesong Li, Yang Gao, Yi Jiang, Ke Jiang, Wei Lü, Xiaojuan Sun, Dabing Li · 发表于：ACS Nano · 年份：2025 · 被引用次数：40 · 研究领域：Solar-Powered Water Purification Methods、Heat Transfer and Optimization、Advanced Sensor and Energy Harvesting Materials

Moisture-electric generators (MEGs) generate power by adsorbing water from the air. However, their performance at low temperatures is hindered due to icing. In the present work, MEG arrays are developed by laser engraving techniques and a modulated low-temperature hydrogel as the absorbent material. LTH effectively captures moisture and maintains ion dissociation and migration even at subzero temperatures. Based on the double electric layer pseudocapacitance model, the oscillating circuit theory is introduced to explain the effects of moisture absorption, evaporation, and ion migration on the output current of the MEG, and the circuit calculations are matched with the experimental results. Molecular dynamics simulations indicate that LTH’s low-temperature stability results from preferential hydrogen bonding between glycerol molecules and H 2 O, which disrupts H 2 O–H 2 O hydrogen bonds and slows water crystallization. A single MEG unit (0.25 cm 2 ) can produce up to ∼0.8 V and ∼21.2 μW/cm 2 at room temperature, and at −35 °C with 16% RH, it generates ∼0.58 V and ∼14.35 μA. MEG realizes the following applications: MEG successfully drives electronic devices in snow; arrays of 16 MEGs can power portable electronics, and 384 MEGs can achieve up to 210 V; MEG absorbs moisture in water and drives LEDs by blowing up; MEG has a flexible wearable nature; MEG is used for respiratory monitoring and photoelectric sensors.