ABSTRACT Thermal management of devices without compromising performance/efficiency remains a central challenge for compact electronics and energy‐intensive devices. Active cooling schemes work well but often consume as much energy as they save. Here, we propose a self‐hygroscopic novel polyacrylamide–LiCl hydrogel for efficient heat removal and energy harvesting. The design is coupled with wind‐driven convection to enhance device performance by removing heat and recovering some of the heat released. The hydrogel absorbs moisture from the surrounding air and gives it back as vapor, so the cooling process is self‐sustaining without the need for active feed water. Once placed on the thermoelectric modules and exposed to a steady stream of air, it drives a sharp 70°C drop in temperature while still generating a significant voltage with the thermoelectric generator. Beyond a certain point, the temperature drop levels off, marking the airflow at which evaporation and convection seem to balance. Finite‐element simulations reproduce this behavior and clarify the role of vapor transport within the porous network. This scalable, self‐sustaining system offers a highly efficient approach to sustainable thermal management, merging passive cooling with energy recovery in a robust platform suited for next‐generation technologies.
Arya et al. (2026) studied this question.