Boosting Solar-Driven Evaporation through an Energy Self-Reinforcing Loop: Harnessing In-Situ Thermoelectric Conversion for Active Airflow Regulation

Solar-driven interfacial evaporation is a promising route for sustainable desalination, yet residual heat dissipation remains a key bottleneck limiting overall energy efficiency. Here, we propose an energy self-reinforcing loop that goes beyond conventional water-electricity cogeneration by using in situ thermoelectric conversion for active airflow regulation. A carbon-based hydrogel-fabric photothermal material (CP@CF) achieves a high evaporation rate of 1.48 kg/m 2 /h under 1 sun, approaching the theoretical limit of planar evaporators. A coupled thermoelectric generator (TEG) harvests waste heat, delivering 76.9 mV and 14.8 mA from a single 2 cm × 2 cm module─ranking among the highest in related studies. In an integrated outdoor system, the generated electricity powers mini-fans to actively regulate airflow, creating a closed-loop enhancement. Outdoor experiments demonstrate that this strategy improves evaporation rates for real-world water sources by 19%, 8%, and 9% for pure water, seawater, and salt lake brine, respectively, compared to passive conditions. This study establishes a new paradigm for self-sustaining solar water treatment through synergistic optimization of photothermal materials and energy architectures.